technetium-tc-99m-tetrofosmin and Coronary-Artery-Disease

In myocardial SPECT imaging with the popularly used 99mTc-sestamibi and 99mTc-tetrofosmin, intense liver uptake leads to a paradoxical decrease of counts in the absence of perfusion abnormalities, making it difficult to assess myocardial perfusion, particularly in the inferior or inferoapical left ventricular wall. 99mTc-N-DBODC5, which is a new lipophilic, mono-cationic nitride myocardial perfusion imaging agent, exhibits high myocardial uptake and excellent bio-distribution kinetics with rapid liver clearance in rats and dogs. 99mTc-N-DBODC5 myocardial imaging during vasodilator stress can determine the severity of stenosis, though underestimates occur with mild coronary stenosis compared to 201Tl, in a similar way to what occurs with 99mTc-sestamibi and 99mTc-tetrofosmin. In particular, 99mTc-N-DBODC5's rapid liver clearance, which may significantly reduce the photon scatter from the liver, allows for the reduction of artifactual decreased myocardial perfusion and the improvement of the diagnostic accuracy of coronary artery disease.

Topics: Animals; Coronary Artery Disease; Coronary Circulation; Coronary Stenosis; Dogs; Heart; Humans; Liver; Organophosphorus Compounds; Organotechnetium Compounds; Technetium Tc 99m Sestamibi; Tissue Distribution; Tomography, Emission-Computed, Single-Photon

Cardiovascular disease is the most frequent cause of death and disability in diabetes, and the morbidity and mortality for coronary artery disease (CAD) in this population is two to four times higher than in nondiabetic subjects. Traditional risk factors do not fully explain the level of cardiovascular risk, and coronary disease events are often silent in diabetic patients. Thus, research has recently focused on improving the risk assessment of an individual patient with new tools in an effort to better identify subjects at highest risk and in need of aggressive management. Cardiovascular imaging has proven very helpful in this regard. Traditional methods to assess CAD are based on detection of obstructive luminal disease responsible for myocardial ischemia. However, acute coronary syndromes often occur in the absence of luminal stenoses. Hence, the utilization of imaging methodologies to visualize atherosclerosis in its presymptomatic stages has received mounting attention in recent years. In this article, we review the current literature on the utility of traditional imaging modalities for obstructive CAD (nuclear and echocardiographic stress testing) as well as atherosclerosis plaque imaging with carotid intima-media thickness and coronary artery calcium for risk stratification of diabetic patients.

Topics: Cardiovascular Diseases; Coronary Artery Disease; Diabetes Complications; Diabetes Mellitus; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Echocardiography, Stress; Humans; Magnetic Resonance Angiography; Myocardial Ischemia; Organophosphorus Compounds; Organotechnetium Compounds; Radiography; Risk Management; Technetium Tc 99m Sestamibi; Thallium Radioisotopes; Tomography, Emission-Computed, Single-Photon; Tunica Intima; Tunica Media

Since Tennant and Wiggers observed that coronary occlusion caused a reduction in cardiac contractile function, a lot has been written about the concept of hibernating myocardium. Known as the 'smart heart', hibernating myocardium is characterized by a persistent ventricular myocardial dysfunction with preserved viability, which improves with the relief of the ischaemia; this chronic downregulation in contractile function being a protective mechanism to reduce oxygen demand and thus ensure myocyte survival. This improvement usually results in an enrichment in the quality of life as well as enhanced ventricular function. In fact, it has been observed that the cardiac event rate in patients with viable dysfunctional left ventricular segments who are medically treated, is higher than the event rate in patients with comparable viability who are revascularized. Different degrees of histological alteration have been seen in hibernating myocardium, ranging from cellular de-differentiation (fetal phenotype) to cellular degeneration. Cellular de-differentiation has been associated with repetitive stunning. On the other hand, cellular degeneration (with more extensive fibrosis) has been associated with chronic low myocardial blood flow and a longer time to recovery after revascularization. These histological patterns may suggest an evolution from cellular de-differentiation to degeneration, which ends in scar formation if no revascularization is performed. In fact, several studies have described the clinical value of identifying and revascularizing hibernating segments as early as possible, to minimize fibrosis and morbidity from adverse events. Detection of hibernating myocardium still remains an important clinical problem. Imaging modalities to assess myocardial viability must differentiate potentially functional tissue from myocardium with no potential for functional recovery. These techniques fall into three broad categories: ventricular function assessment, myocardial perfusion imaging and myocardial metabolic imaging. PET imaging with fluorine-18 fluorodeoxyglucose (18F-FDG) and 11C-acetate, single photon emission computed tomography (SPECT) with thallium and 99mTc-sestamibi, dobutamine echocardiograpy, magnetic resonance imaging (MRI) and fast computed tomography (CT) have been used for this purpose. PET imaging, in both perfusion and glucose metabolic activity, has become a standard for myocardial viability assessment, however, similar information may be ava

Topics: Coronary Artery Disease; Fluorodeoxyglucose F18; Heart; Heart Function Tests; Humans; Myocardial Stunning; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Technetium Tc 99m Sestamibi; Thallium Radioisotopes; Tomography, Emission-Computed; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

Myocardial perfusion single-photon emission computed tomography (SPECT) imaging with stress is a useful examination for detecting coronary artery disease. Since the presence of artifacts is remaining challenges, we aimed to define the minimum intensity of low-grade exercise stress levels combined with drug stress to reduce undesired artifacts and their related factors.. We divided patients with suspicious coronary artery disease into 4 groups as follows: group A, adenosine triphosphate (ATP) for 6 min; group A + 25 W, ATP + 25 W exercise for 6 min; group A + 35 W, ATP + 35 W exercise for 6 min; group A + 45 W, ATP + 45 W exercise for 6 min) and enrolled only those whose summed stress scores were < 3. Undesired artifacts were evaluated on the basis of heart-to-liver activity (H/L) ratio and heart-to-10 pixels below the heart (H/below the H) ratio.. The logarithmic values of H/L and H/below the H ratios were significantly higher in groups A + 35 W and A + 45 W than in group A (p < 0.05, each). In all the patients, the logarithmic values of H/L and H/below the H ratios positively correlated with the increment of rate pressure product (RPP, p = 0.002 and p = 0.005, respectively) after stress in the univariate analysis. The left ventricular end-diastolic volume (LVEDV) after stress (p = 0.002) negatively correlated with the logarithmic value of H/below the H ratio, but not H/L ratio. Although the increment of RPP was independently associated with the logarithmic values of both H/L (p = 0.001) and H/below the H ratios (p = 0.005), LVEDV was also independently associated with the logarithmic value of H/below the H ratio (p < 0.001) in multivariate regression analysis under adjusting with age and sex.. ATP plus ≥35 W exercise stress for 6 min was useful for reducing undesired artifacts after stress in myocardial perfusion SPECT. LVEDV after stress in addition to the increment of RPP was independently associated with the H/below the H ratio, but not the H/L ratio.

Topics: Adenosine Triphosphate; Aged; Aged, 80 and over; Artifacts; Coronary Artery Disease; Exercise Test; Female; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Predictive Value of Tests; Radiopharmaceuticals; Reproducibility of Results; Single Photon Emission Computed Tomography Computed Tomography; Time Factors

The aim of the study was to assess the agreement between the left ventricular ejection fraction (LVEF) values obtained with IQ-SPECT and those obtained with a conventional gamma camera equipped with low-energy high-resolution (LEHR), considered as the method of reference.. Gated-stress MPI using 99mTc-tetrofosmin was performed in 55 consecutive patients. The patients underwent two sequential acquisitions (Method A and B) performed on Symbia-IQ SPECT with different acquisition times and one (Method C) on a Ecam SPECT equipped with LEHR collimators. The values of the different datasets were compared using the Bland-Altman analysis method: the bias and the limits of agreement (LA) were estimated in a head-to-head comparison of the three protocols.. In the (Method A-Method C) comparison for LVEF, the bias was 3.8% and the LAs ranged from - 9.3% to 16.8%. The agreement was still lower between Method B and C, whilst only slightly improved when Methods A and B were compared.. The wide amplitude in LA intervals of about 30% indicates that IQ and LEHR GSPECT are not interchangeable. The values obtained with IQ-SPECT should only be used with caution when evaluating the functional state of the heart.

Topics: Adult; Aged; Aged, 80 and over; Algorithms; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; Coronary Artery Disease; Female; Humans; Image Processing, Computer-Assisted; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Software; Stroke Volume

The introduction of a camera-based dose-reduction strategy in myocardial perfusion imaging (MPI) clinical setting entails the definition of objective and reproducible criteria for establishing the amount of activity to be injected.. The aim is to evaluate the impact of count statistics on the estimation of summed-scores (SS), end-diastolic volume (EDV), end-systolic volume (ESV), and ejection fraction (EF).. A significant difference between SS values of half-time and quarter-time stress scans was found for overweight group (P = .006). Post hoc test showed significant differences for ESV (P < .05), EDV (P < .01) and EF (P < .05) between half-time and quarter-time scans for both patient groups.. The reduction of the count-statistics to a quarter of the MPI reference influenced negatively the quantification in overweight patients. The decrease of radiopharmaceutical activity to 25% of the reference seems practicable for normal-weight patients, while it is more appropriate an activity reduction limited to 50% for overweight and obese patients.

Topics: Aged; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; Coronary Artery Disease; Female; Humans; Image Enhancement; Image Interpretation, Computer-Assisted; Male; Myocardial Perfusion Imaging; Obesity; Organophosphorus Compounds; Organotechnetium Compounds; Radiation Exposure; Radiation Protection; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Stroke Volume

The decreasing image quality in heavier patients can be compensated by administration of a patient-specific dose in myocardial perfusion imaging (MPI) using a cadmium zinc telluride-based SPECT camera. Our aim was to determine if the same can be achieved when using a conventional SPECT camera.. 148 patients underwent SPECT stress MPI using a fixed Tc-99m tetrofosmin tracer dose. Measured photon counts were normalized to administered tracer dose and scan time and were correlated with body weight, body mass index, and mass per length to find the best predicting parameter. From these data, a protocol to provide constant image quality was derived, and subsequently validated in 125 new patients.. Body weight was found to be the best predicting parameter for image quality and was used to derive a new dose formula; A admin (MBq) = 223·body weight (kg)(0.65)/T scan (min). The measured photon counts decreased in heavier patients when using a fixed dose (P < .01) but this was no longer observed after applying a body-weight-dependent protocol (P = .20).. Application of a patient-specific protocol resulted in an image quality less depending on patient's weight. The results are most likely independent of the type of SPECT camera used, and, hence, adoption of patient-specific dose and scan time protocols is recommended.

Topics: Aged; Body Weight; Contrast Media; Coronary Artery Disease; Drug Administration Schedule; Equipment Design; Equipment Failure Analysis; Female; Gamma Cameras; Humans; Image Enhancement; Image Interpretation, Computer-Assisted; Male; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Patient-Centered Care; Patient-Specific Modeling; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Tomography, Emission-Computed, Single-Photon

The aim of the study was to investigate whether myocardial perfusion imaging at 15 min after injection (T15) is more accurate in detecting coronary artery disease than that at 45 min (T45).. Two-day stress/rest 99mTc-tetrofosmin gated SPECT was performed at T15 and T45 in 50 patients. Coronary angiography was considered when poststress and resting images were discordant. Tracer washout rates were calculated for the myocardium, liver, and subdiaphragmatic region. Perfusion sum difference scores were derived using QPS software.. T15 and T45 were discordant in 18/50 (36%) patients. In 16/18 patients (89%) discordant deficits were more apparent at T15. A total of 13/16 patients underwent coronary angiography, of whom 12 had coronary artery disease. Poststress, but not resting, left ventricular ejection fraction was lower at T15 (P=0.02). Sum difference scores were higher at T15 [2.2 (1.9)] than at T45 [1.6 (1.7); P<0.05]. Tracer washout rates from the liver [46 (13.3)%] and subdiaphragmatic region [36 (21.3)%] were significant (P<0.0001), but there was no change in myocardial activity.. T15 detected more abnormalities than did T45. The reduction in left ventricular ejection fraction after stress may result from adenosine-induced poststunning at T15. Accordingly, the T15 protocol may be useful in the assessment of hibernating myocardium. Contrasting myocardial and hepatic washout rates may be attributable to differential ABC transporter expression.

Topics: Adenosine; Aged; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; Coronary Artery Disease; Female; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Stroke Volume; Technetium Tc 99m Sestamibi; Time Factors; Ventricular Dysfunction, Left

Estimation of myocardial blood flow (MBF) and coronary flow reserve (CFR) by SPECT myocardial perfusion imaging (MPI) remains challenging. Our aim was to approximate MBF and CFR by quantifying the absolute Tc-99m tetrofosmin retention in the myocardium via gated-SPECT/CT MPI.. Tracer retention was calculated on the basis of the microsphere kinetic model and served as an index of MBF at stress and rest (sMBFi, rMBFi). CFR was given by the sMBFi/rMBFi ratio. A planar first-pass acquisition during dipyridamole stress and at rest provided the data for tracer input determination. The input was represented by the integral of a gamma variate fitted on the time-activity curve of the left ventricle. Gated-SPECT/CT was performed 1 h post tracer injection and myocardial activity was measured in attenuation-corrected transaxial slices by a threshold VOI. The input was also compensated for tissue attenuation by measuring the distance from the centre of the left ventricle to the body surface on fused SPECT/CT slices. Input and uptake results were adjusted for planar-SPECT counting geometry differences by the aid of a phantom experiment. Thirty-nine subjects with low probability of coronary artery disease (CAD), age lower than 75 years and normal MPI (control group) were compared with 57 patients with documented CAD (CAD group).. CFR and sMBFi values of CAD patients (1.39 ± 0.37 and 1.42 ± 0.35 ml/min/g) were considerably lower (p < 0.0001) than controls (1.68 ± 0.25 and 1.72 ± 0.37 ml/min/g). Significant difference in CFR (p = 0.03) was also noted between CAD patients with normal MPI (1.48 ± 0.38) and controls. However, sMBFi managed to discriminate certain CAD subgroups (normal MPI/ischemia/scar/scar and ischemia) more efficiently than CFR. Maximum heart rate-blood pressure product (RPP) during stress was an independent predictor of sMBFi and CFR. The other independent CFR correlates were resting RPP and diabetes mellitus, while sMBFi was associated with age, sex, smoking, and stress perfusion defects.. Despite the low myocardial extraction fraction of Tc-99m tetrofosmin, an approximation of MBF and CFR is feasible with gated-SPECT/CT MPI. These flow indices together were able to discriminate CAD patients from controls and stratify different patient subgroups.

Topics: Adult; Aged; Aged, 80 and over; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; Case-Control Studies; Coronary Artery Disease; Feasibility Studies; Female; Fractional Flow Reserve, Myocardial; Heart; Humans; Male; Middle Aged; Multimodal Imaging; Myocardium; Organophosphorus Compounds; Organotechnetium Compounds; Phantoms, Imaging; Rest; Stress, Physiological; Time Factors; Tomography, X-Ray Computed

Myocardial perfusion SPECT (MPS) traditionally requires the patient to be in the supine position, but diaphragmatic attenuation of the inferior wall reduces test specificity. The aim of this study was to assess the feasibility of combined MPS in the supine and prone positions using a novel cadmium zinc telluride (CZT) camera.. A total of 276 consecutive patients with suspected/known coronary artery disease (CAD) who underwent single-day (99m)Tc-tetrofosmin or (99m)Tc-sestamibi stress/rest CZT SPECT, were enrolled in the study. Seventy-six underwent coronary angiography. Five-minute scan in the supine (S) position and thereafter in the prone (P) position produced images that were visually interpreted to obtain summed stress (SSS) and rest (SRS) scores. A combined stress score (C-SSS) was calculated by grouping anterior perfusion defects observed during supine imaging with inferior half segments observed during prone imaging. The SSS for the supine, prone, and combined protocols were 9±8, 7±8, and 7±8, respectively (P<0.0001). The SRS were 5±8, 4±7, and 6±7, respectively (P=0.005). The area under the ROC curve for the S-SSS, P-SSS, and C-SSS scores was 0.815 (95% CI: 0.713-0.917), 0.813 (0.711-0.914), and 0.872 (0.783-0.961), respectively. Corresponding sensitivities and specificities for detecting CAD were 87% and 50%, 80% and 77%, and 85% and 82%, respectively. C-SSS had significantly better specificity and accuracy than S-SSS (P<0.05).. Combined imaging with a CZT camera is suitable for routine clinical MPS and provides greater diagnostic accuracy than supine imaging alone.

Topics: Aged; Aged, 80 and over; Coronary Artery Disease; Humans; Middle Aged; Myocardial Perfusion Imaging; Myocardium; Organophosphorus Compounds; Organotechnetium Compounds; Radiography; Radiopharmaceuticals; Sensitivity and Specificity; Technetium Tc 99m Sestamibi; Tomography, Emission-Computed, Single-Photon

Left ventricular ejection fraction (LVEF) is the single most important predictor of prognosis in patients with coronary artery disease (CAD) and left ventricular (LV) dysfunction. Equilibrium radionuclide ventriculography (ERNV) is considered the most reliable technique for assessing LVEF. Most of these patients undergo two dimensional (2D) echocardiography and myocardial viability study using gated myocardial perfusion imaging (MPI) or gated F-fluorodeoxyglucose (F-FDG) PET. However, the accuracy of LVEF assessed by these methods is not clear. This study has been designed to assess the correlation and agreement between the LVEF measured by 2D echocardiography, gated blood pool single photon emission computed tomography (SPECT), Tc tetrofosmin gated SPECT, and F-FDG gated PET with ERNV in CAD patients with severe LV dysfunction.. Patients with CAD and severe LV dysfunction [ejection fraction (EF) <35 assessed by 2D echocardiography] were prospectively included in the study. These patients underwent ERNV along with gated blood pool SPECT, Tc tetrofosmin gated SPECT, and F-FDG gated PET as per the standard protocol for myocardial viability assessment and LVEF calculation. Spearman's coefficient of correlation (r) was calculated for the different sets of values with significance level kept at a P-value less than 0.05. Bland-Altman plots were inspected to visually assess the between-agreement measurements from different methods.. Forty-one patients were prospectively included. LVEF calculated by various radionuclide methods showed good correlation with ERNV as follows: gated blood pool SPECT, r=0.92; MPI gated SPECT, r=0.85; and F-FDG gated PET, r=0.76. However, the correlation between 2D echocardiography and ERNV was poor (r=0.520). The Bland-Altman plot for LVEF measured by all radionuclide methods showed good agreement with ERNV. However, agreement between 2D echocardiography and ERNV is poor, as most of the values in this plot gave a negative difference for low EF and a positive difference for high EF. The mean difference between various techniques [2D echocardiography (a), gated blood pool SPECT (b), MPI gated SPECT (c), F-FDG gated PET (d)] and ERNV (e) was as follows: (a)-(e), 3.3; (b)-(e), 5; (c)-(e), 1.1; and (d)-(e), 2.9. The best possible correlation and agreement was found between MPI gated SPECT and ERNV.. This study showed good correlation and agreement between MPI gated SPECT and F-FDG gated PET with ERNV for LVEF calculation in CAD patients with severe LV dysfunction. Thus, subjecting patients who undergo viability assessment by MPI gated SPECT or F-FDG gated PET to a separate procedure like ERNV for LVEF assessment may not be warranted. As the gated blood pool SPECT also showed good correlation and agreement with ERNV for LVEF assessment in CAD patients with severe LV dysfunction, with better characteristics than ERNV, it can be routinely used whenever accurate LVEF assessment is needed.

Topics: Adult; Aged; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; Coronary Artery Disease; Echocardiography; Female; Fluorodeoxyglucose F18; Gated Blood-Pool Imaging; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Positron-Emission Tomography; Stroke Volume; Ventricular Dysfunction, Left

The goal of this study was to compare Emory Cardiac Toolbox (ECTb), quantitative gated SPECT (QGS), four-dimensional single photon emission computed tomography (4D-MSPECT) and Myometrix cardiac software programs for the assessment of left ventricular ejection fraction (LVEF) using 99mTc-tetrofosmin-gated SPECT/CT [myocardial perfusion SPECT (MPS)] and correlate them with the LVEF values derived from equilibrium radionuclide ventriculography (ERNV) in patients with known/suspected coronary artery disease (CAD).. A total of 109 patients (80 men, 29 women) were recruited into the study. Fifty-five patients had known CAD and 54 were referred with suspicion of CAD. All the patients underwent ERNV and MPS as per the standard protocol. ERNV was processed using the vendor-provided 'EF analysis' and gated MPS was processed using individual software programs.. The mean LVEF on ERNV was 47.9 ± 15.5%. The mean LVEF values for ECTb, QGS, 4D-MSPECT and Myometrix were 51.5 ± 19.6, 51.0 ± 18.6, 57.1 ± 19.3 and 49.7 ± 19%, respectively. On correlation analysis, a very strong positive correlation was observed between LVEF values derived by ERNV and those derived by the MPS software programs: ECTb (r=0.842, P<0.0001), QGS (r=0.835, P<0.0001), 4D-MSPECT (r=0.830, P<0.0001) and Myometrix (r=0.875, P<0.0001). Significant correlation was also seen for LVEFs among the four software programs. Normal cutoff values for ejection fraction on ECTb, QGS, 4D-MSPECT and Myometrix were 56, 52, 54 and 51%, respectively, using a 50% or more cutoff value on ERNV.. A strong correlation was observed among ECTb, QGS, 4D-MSPECT and Myometrix software programs when compared with ERNV and also between them for assessment of LVEF. However, there are subtle differences in the objective values of ejection fraction generated by individual software, which must be taken into account for clinical studies.

Topics: Adult; Aged; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; Coronary Artery Disease; Female; Gated Blood-Pool Imaging; Heart Ventricles; Humans; India; Male; Middle Aged; Multimodal Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Positron-Emission Tomography; Reference Standards; ROC Curve; Software; Stroke Volume; Tomography, X-Ray Computed

Coronary artery disease is associated with multiple genetic and environmental risk factors. In this study, we evaluated the correlation of angiotensin l-converting enzyme (ACE) (I/D) and ApoE gene polymorphisms (E2, E3, E4 and g.-219G/T) with myocardial perfusion. We examined 410 patients using exercise-rest myocardial perfusion single photon emission computed tomography (SPECT), in which the summed stress score (SSS), summed rest score (SRS) and summed difference score (SDS) indexes were calculated. Homozygotes for the ACE D allele had greater mean values of SSS (P<0.001) and SDS (P<0.001). In addition, E3 homozygotes, E4 heterozygotes and E4 homozygotes had significantly higher values of SSS and SDS compared with E3 heterozygotes (P<0.001); E4 homozygotes had significantly higher values of SSS and SDS compared with E3 homozygotes. Furthermore, for the g.-219G>T polymorphic site at the promoter region of ApoE gene, the mean values of SSS and SDS were significantly higher for T heterozygotes/homozygotes than for GG homozygotes. Adjusting for all demographic and clinical data using multiple linear regression analysis it was found that ACE D and both ApoE genotypes were independent predictors with a cumulative contribution for the prediction of SSS and SDS. Furthermore, logistic regression analysis revealed that all three genotypes had an independent predictive ability for abnormal SSS (SSS>2). These data provide the first evidence of an association and significant cumulative contribution of the aforementioned genotypes in myocardial perfusion with E4 allele having the strongest association followed by ACE D and ApoE g.-219T alleles.

Topics: Adult; Aged; Aged, 80 and over; Apolipoproteins E; Coronary Artery Disease; Coronary Circulation; Exercise Test; Female; Gene Frequency; Genotype; Heart; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Peptidyl-Dipeptidase A; Thallium Radioisotopes; Tomography, Emission-Computed, Single-Photon

Percutaneous transluminal coronary angioplasty is a well-established therapeutic method in selected patients with coronary artery disease. The aim of this study was to assess the incremental prognostic value of technetium-99m ((99m)Tc)-tetrofosmin myocardial gated-single- photon emission computed tomography (SPECT) in asymptomatic patients after coronary artery stenting.. A total of 246 consecutive patients (aged 55.5 +/- 8.2 years, 182 men) participated in the study with a median follow-up of 9.5 years (interquartile ra 5.8-10.5 years). All patients underwent exercise gated-SPECT myocardial imaging within 5-7 months. Myocardial scintigrams were performed using 99mTc-tetrofosmin, and were evaluated calculating the summed stress score (SSS), summed rest score (SRS), and summed difference score (SDS) indexes. Cardiovascular death and non-fatal myocardial infarction were considered as hard cardiac events, and late revascularization (>3 months after myocardial SPECT) procedures as soft events. Receiver-operating characteristic (ROC) analysis was used to test the prognostic ability of SSS and SDS for cardiac events. Cox proportional hazards models were used to evaluate the incremental value of SPECT variables.. Cardiac death occurred in 12 (4.9%) patients and non-fatal myocardial infarction in 20 (8.1%) patients. In addition, 60 (24.4%) patients underwent a late revascularization procedure. Using ROC analysis the optimal cut-offs of SSS (AUC = 0.94; 95% CI 0.92-0.97) and SDS (AUC = 0. 76; 95% CI 0.70-0.82) for the prediction of cardiac events were 10 and 1.7, respectively. Multiple Cox regression analyses revealed that SSS > 10 (HR = 24.2; 95% CI 7.44-78.79) and SDS > 1.7 (HR = 2.72; 95% CI 1.23-6.00) provided incremental prognostic value over clinical and exercise test data for the composite end points of any cardiac event.. (99m)Tc-tetrofosmin myocardial gated- SPECT, performed 6 months post-percutaneous coronary intervention (PCI), provides incremental prognostic information for the prediction of cardiac events in asymptomatic patients after PCI.

Topics: Angioplasty, Balloon, Coronary; Coronary Artery Disease; Greece; Humans; Incidence; Organophosphorus Compounds; Organotechnetium Compounds; Outcome Assessment, Health Care; Prognosis; Radiopharmaceuticals; Reproducibility of Results; Risk Assessment; Risk Factors; Sensitivity and Specificity; Survival Analysis; Survival Rate; Tomography, Emission-Computed, Single-Photon; Treatment Outcome

Even after recanalization of a chronic total coronary occlusion, functional recovery is incomplete and parts of the myocardium remain hypoperfused. In this randomized, placebo-controlled, and double-blinded study, we investigated relative changes in myocardial perfusion and glucose metabolism induced by intracoronary administration of blood-derived circulating progenitor cells (CPCs), compared with the natural course in a control group after recanalization of total coronary occlusion.. After recanalization of total coronary occlusion, 26 patients were randomly assigned to the CPC treatment or placebo group. Regional myocardial perfusion and glucose metabolism were assessed by 99mTc-tetrofosmin SPECT and 18F-FDG PET at baseline (after recanalization of total coronary occlusion) and 3 mo after the administration of 69 +/- 14 x 10(6) CPCs or cell-free serum, respectively. Segments were classified as "normal," "perfusion-metabolism mismatch" (dysfunctional segments with a 99mTc-tetrofosmin-18F-FDG mismatch), or "scar.". In contrast to the placebo group, CPC administration resulted in a significant decrease in the number of segments with a perfusion-metabolism mismatch, from 3.0 +/- 0.5 to 1.7 +/- 0.6 segments (P < 0.05 vs. baseline). Of the normal segments at baseline, 2.7% in the CPC group and 30% in the placebo group revealed a perfusion-metabolism mismatch at follow-up after 3 mo (P < 0.05 vs. placebo).. Intracoronary administration of CPCs significantly reduces the amount of myocardium with a perfusion-metabolism mismatch and prevents areas with normal perfusion and metabolism after recanalization of total coronary occlusion from becoming dysfunctional during the next 3 mo. These results show that PET and SPECT can be used to monitor the effect of progenitor cells on myocardial integrity. More important, they provide evidence supporting expansion of the use of progenitor cell treatment to chronic coronary artery disease.

Topics: Coronary Artery Disease; Coronary Circulation; Glucose; Humans; Myocardial Revascularization; Myocardium; Organophosphorus Compounds; Organotechnetium Compounds; Stem Cell Transplantation; Time Factors

To compare the prognostic ability of the imaging agents 99mTc-sestamibi versus 99mTc-tetrofosmin to predict mortality outcomes in patients with documented coronary artery disease and undergoing vasodilator stress testing.. The study included 2147 consecutive patients who underwent rest and stress single photon emission computed tomographic (SPECT) examination with either 99mTc-sestamibi (n=1128) or 99mTc-tetrofosmin (n=1019). Information relating to all-cause death and cardiovascular death was collected over a 4-year study period. Unadjusted Kaplan-Meier estimates were compared for the two imaging agents. Cox proportional hazard models were examined to determine the incremental contribution of SPECT sum stress score (SSS) and the imaging agent after adjusting for clinical and demographic characteristics. Additionally, the interaction between SSS and agent was examined to determine if the effect of SSS on prognosis was different for the two agents.. Vasodilator agents were used for stress testing in all patients who received 99mTc-tetrofosmin and 99mTc-sestamibi. Despite differences in patient risk factors Kaplan-Meier estimates were similar for the two groups of patients. Resulting P-values for differences between models for the end points of (1) death from any cause and (2) cardiovascular death showed that SSS combined with clinical index was significantly better than a model that adjusted for only baseline characteristics (P<0.0001 for both endpoints). The addition of imaging agent (99mTc-tetrofosmin or 99mTc-sestamibi) to the model containing both SSS and the clinical characteristics did not show further significant improvement (P=0.62, P=0.96 for death from any cause and cardiovascular death, respectively).. The type of clinically available 99mTc-labelled myocardial perfusion agents did not affect interpretation of results for prognostic assessment.

Topics: Aged; Coronary Artery Disease; Female; Humans; Male; Organophosphorus Compounds; Organotechnetium Compounds; Predictive Value of Tests; Radiopharmaceuticals; Technetium Tc 99m Sestamibi; Tomography, Emission-Computed, Single-Photon; Vasodilator Agents

To test the association of early post-stress lung/heart ratio (LHR) of 99mTc tetrofosmin radioactivity with gated-SPECT findings and angiographic results.. We studied 158 consecutive patients, with stress/rest 99mTc tetrofosmin myocardial SPECT and coronary angiography. Rest scans were obtained as gated SPECT and the left ventricular ejection fraction and end diastolic volume were calculated. To evaluate myocardial ischaemia, we calculated the summed stress score, summed rest score and summed difference score indices. For the LHR calculation, we acquired an anterior image, 4-6 min after radiotracer injection at stress; LHR was defined as mean counts/pixel in the lung region of interest divided by the mean counts/pixel in the myocardial region of interest.. An early post-stress LHR value of 0.500 was defined as the upper normal limit. The most significant correlation (P<0.001) was observed among early post-stress LHR, summed stress score and the number of stenosed vessels. The incidence of multi-vessel coronary artery disease in the subgroup of patients with increased values of early post-stress LHR, was significantly higher than in the normal group (81% vs. 42%, P<0.001). There was a significant difference (P<0.001) of the early post-stress LHR value between patients with normal coronary arteries or one-vessel disease and patients with multi-vessel disease. Early post-stress LHR was an independent predictor of multi-vessel coronary artery disease (coefficient 1.85, SD 0.16, P<0.001), with an incremental value for its identification.. Our results suggest that early post-stress 99mTc tetrofosmin LHR appears to be a useful index of extensive myocardial ischaemia dysfunction and multi-vessel coronary artery disease.

Topics: Aged; Aged, 80 and over; Coronary Artery Disease; Coronary Vessels; Exercise Test; Female; Heart; Humans; Image Interpretation, Computer-Assisted; Lung; Male; Middle Aged; Myocardial Ischemia; Myocardium; Organophosphorus Compounds; Organotechnetium Compounds; Radionuclide Imaging; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Statistics as Topic

We sought to determine whether drinking lemon juice reduces extra-cardiac activity and improves image quality on (99m)Tc-tetrafosmin myocardial single photon emission computed tomography (SPECT).. Eighty male patients were enrolled in this study and divided into four groups with 20 patients in each group. Each patient received 259-333 MBq tetrofosmin. Ten minutes after injection no action was taken for group 1 (G1), patients in group 2 (G2) each drank 250 ml of water, patients in group 3 (G3) each drank 250 ml of whole milk, and patients in group 4 (G4) each drank 250 ml diluted lemon juice. Myocardial perfusion imaging without attenuation correction was performed after a 1 day rest-stress protocol. Both rest and stress images were aligned at corresponding slices for comparison. Interfering activity was determined visually on reconstructed images, and the heart-to-liver (H/L) ratios were calculated with planar images at 25-30 min and at 45-50 min.. Interfering activity was seen in 80% of G1, 70% of G2, 60% of G3, and 35% of G4 (G4 vs. G1, P=0.006) on rest images, and in 70% of G1, 60% of G2, 55% of G3, and 30% of G4 (G4 vs. G1, P=0.014) on stress images at 25-30 min. It was also observed in 60% of G1, 50% of G2, 45% of G3, and 15% of G4 (G4 vs. G1, P=0.006) on rest images, and in 50% of G1, 45% of G2, 40% of G3, and 10% of G4 (G4 vs. G1, P=0.011) on stress images at 45-50 min. The mean H/L ratios of rest images were 0.47+/-0.13 for G1, 0.71+/-0.17 for G2, 0.65+/-0.12 for G3, and 0.93+/-0.23 for G4 at 25-30 min, and 0.63+/-0.14 for G1, 0.73+/-0.14 for G2, 0.85+/-0.25 for G3, and 1.15+/-0.25 for G4 at 45-50 min. On stress images, they were 0.49+/-0.11 for G1, 0.74+/-0.16 for G2, 0.69+/-0.11 for G3, and 0.98+/-0.22 for G4 at 25-30 min, and 0.66+/-0.15 for G1, 0.77+/-0.11 for G2, 0.89+/-0.26 for G3, and 1.21+/-0.19 for G4 at 45-50 min.. Drinking 250 ml of diluted lemon juice accelerates the transit of tetrofosmin through the liver parenchyma and improves image quality on (99m)Tc-tetrafosmin myocardial SPECT.

Topics: Administration, Oral; Adult; Aged; Artifacts; Beverages; Biliary Tract; Citrus; Coronary Artery Disease; Female; Humans; Image Enhancement; Liver; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Plant Extracts; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Tomography, Emission-Computed, Single-Photon

Extra-cardiac activity can interfere with observer interpretation of myocardial perfusion single photon emission computed tomography (SPECT) images. Fatty meals and drinks to reduce interference have been tested; however, a simple study of delayed imaging with (99m)Tc-tetrofosmin and (99m)Tc-sestamibi has not been specifically addressed. The aim was to quantify the effects of imaging time, radiopharmaceutical and oral administration of full fat milk and water on interfering activity.. Myocardial perfusion SPECT images were acquired using either tetrofosmin or sestamibi. Patients were imaged at 0.5, 1 or 2 h post-injection (tetrofosmin, 59; sestamibi, 72). Additional groups of patients were imaged either with or without milk (tetrofosmin, 54; sestamibi, 45) and with milk and water (sestamibi, 30). A myocardial region was drawn on the anterior projection and a thin adjacent extra-cardiac region was generated automatically. The count density ratio was calculated and validated with a trial of five observers. A decreasing ratio correlated significantly with observer rank of increasing interference with SPECT image interpretation (r=0.95, P=0.001).. The ratio improved significantly as the imaging time increased for both tetrofosmin and sestamibi groups (P<0.05). The groups given milk or milk plus water showed no significant improvement against control groups (P > or = 0.2). There was no significant difference between tetrofosmin and sestamibi at any time point (P > or = 0.4).. Image interpretation may be improved by delayed imaging for tetrofosmin and sestamibi. However, in contrast with common practice, the administration of milk or water appears to be of no clinical value compared with delayed imaging, and there is no significant difference between interfering activity from tetrofosmin and sestamibi.

Topics: Administration, Oral; Animals; Coronary Artery Disease; Female; Humans; Male; Middle Aged; Milk; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Technetium Tc 99m Sestamibi; Time Factors; Tomography, Emission-Computed, Single-Photon; Water

Information on the prognostic value of noninvasive stress imaging techniques in the elderly is relatively scarce. This study assessed the prognostic value of dobutamine stress (99m)Tc-tetrofosmin SPECT for the prediction of mortality and cardiac events in elderly patients.. Clinical information and SPECT results were analyzed for 272 consecutive patients > or = 65 y old (mean age, 71 +/- 5 y; range, 65-87 y) with limited exercise capacity. Follow-up was complete in 270 patients (99.3%); 23 underwent revascularization within 60 d of the scintigraphy and were excluded. Abnormal findings were defined as the presence of a fixed or reversible perfusion defect. A summed stress score was obtained to estimate the extent and severity of perfusion defects. The incremental prognostic value of SPECT over clinical data was evaluated according to 3 multivariate models, which included any SPECT abnormality, the presence of a fixed or reversible defect, and the summed stress score.. During the follow-up (3.3 +/- 1.4 y), 59 patients died (29 cardiac deaths), 16 had a nonfatal infarction, and 49 underwent late revascularization. Abnormal scan findings were present for 140 patients (57%). The annual event rates for total mortality, cardiac death, and cardiac death or nonfatal infarction were, respectively, 3.2%, 0.2%, and 0.7% when scan findings were normal and, respectively, 9.5%, 4.3%, and 8% when scan findings were abnormal (all P < 0.0001). Multivariate analysis showed that abnormal scan findings, the presence of a fixed or reversible defect, and the summed stress score provided incremental prognostic information over clinical data. The presence of abnormal scan findings was independently associated with an increased risk for total mortality, cardiac death, and cardiac death or nonfatal infarction (respectively, hazard ratio 3.4 [95% CI, 1.8-6.5], 12.1 [95% CI, 2.9-51.5], and 9.0 [95% CI, 2.8-29.6]).. Dobutamine stress (99m)Tc-tetrofosmin SPECT provides incremental prognostic information for the prediction of total mortality and cardiac events in elderly patients.

Topics: Aged; Aged, 80 and over; Causality; Comorbidity; Coronary Artery Disease; Dobutamine; Exercise Test; Female; Geriatric Assessment; Humans; Male; Myocardial Infarction; Netherlands; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Radiopharmaceuticals; Reproducibility of Results; Risk Assessment; Risk Factors; Sensitivity and Specificity; Survival Analysis; Tomography, Emission-Computed, Single-Photon

Coronary artery disease impairs cardiac vasodilatory reserve. A low ratio of cardiac to hepatic vasodilatory reserve may be diagnostic for coronary artery disease.. To compare the ratio of cardiac to hepatic uptake of 99mTc-tetrofosmin during adenosine infusion and at rest in patients with and without coronary artery disease in order to determine whether the ratio was significantly different between the two groups.. Fifty-one patients who underwent coronary angiography and adenosine stress myocardial perfusion imaging using 99mTc-tetrofosmin were studied retrospectively. Anterior planar images from the single photon emission computed tomography (SPECT) raw data were used to draw regions of interest around the heart and liver. The counts per pixel in each region were used to calculate the stress ratio (SR) and the rest ratio (RR) as follows: SR = (cardiac counts per pixel)at stress/(hepatic counts per pixel)at stress; RR = (cardiac counts per pixel)at rest/(hepatic counts per pixel)at rest. The SR and SR/RR ratios were compared in patients with and without significant coronary artery disease. Receiver operating characteristic curves were drawn for SR and SR/RR.. The SR and SR/RR ratios were significantly lower in patients with significant coronary artery disease than in patients without (P<0.001). A cut-off ratio of SR/RR = 1.00 yielded 87% sensitivity and 74% specificity for the detection of significant coronary artery disease. Combining SR/RR with standard SPECT image interpretation increased the sensitivity without substantially changing the specificity in comparison with standard SPECT image interpretation only.. Comparison of cardiac to hepatic 99mTc-tetrofosmin concentration at rest and under adenosine stress provides useful diagnostic information for the assessment of the presence of significant coronary artery disease.

Topics: Adenosine; Coronary Artery Disease; Female; Heart; Humans; Image Interpretation, Computer-Assisted; Infusions, Intravenous; Liver; Male; Middle Aged; Myocardium; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Radionuclide Imaging; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity

The purpose of the present study was to evaluate the feasibility and diagnostic accuracy of same day short rest-dobutamine stress Tetrofosmin (TF) SPECT imaging protocol and to compare TF SPECT results with MIBI SPECT in the same subjects who were unable to perform treadmill exercise or were unsuitable for pharmacological vasodilator stress.. The study group consisted of 19 patients (2 female and 17 male, with a mean age of 53.8 +/- 7.9 yrs) in whom coronary artery disease (CAD) had been proven or excluded at coronary angiography (CA). MIBI SPECT imaging was performed first. TF SPECT images were obtained one week after MIBI imaging. Immediately after the rest SPECT imaging in both of the MIBI and TF studies, patients underwent dobutamine stress tests. Rest-stress radiotracer doses and dobutamine doses were the same for both TF and MIBI studies. While 60 min waiting periods were applied for MIBI study, only 30 min waiting periods were applied for TF study after the rest and stress injections. Images were evaluated by visual and quantitative analysis.. Dobutamine stress parameters were similar for both studies. Although in TF study, the time between radiopharmaceutical injection and imaging was shorter than in MIBI study, there was no significant difference between heart-to-liver (H/Li) and heart-to-lung (H/Lu) ratios. According to CA results, diagnostic accuracy was similar for TF and MIBI. While sensitivity, specificity and accuracy for TF study were calculated as 82%, 84% and 82%, respectively, the corresponding values for MIBI were 82%, 88% and 84%, respectively. This clinical study has shown comparable diagnostic performance for the detection of CAD between MIBI and TF. Good correlation was found between segmental analysis for both studies.. MIBI and TF showed similar perfusion defects and good segmental correlation during dobutamine stress with the same quality images. Both radiopharmaceuticals may be acceptable with this imaging protocol. Besides this, TF study showed better reversibility degree (55%) in a shorter time when compared to MIBI study (25%) in perfusion defects (especially in segments with severely decreased perfusion or no uptake).

Topics: Adult; Aged; Cardiotonic Agents; Coronary Artery Disease; Dobutamine; Exercise Test; Female; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Rest; Sensitivity and Specificity; Technetium Tc 99m Sestamibi; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

This study was performed to assess whether post-stress and rest functional parameters, as measured by gated-SPECT, provide additional predictive value for long-term prognosis, over clinical and perfusion data in patients (pts.) with low left ventricular ejection fraction (LVEF).. 647 consecutive pts. underwent stress/rest gated-SPECT, and 497 were followed for a mean period of 516 +/- 264 days. Segmental perfusion and motion/thickening (post-stress and rest) were analysed visually, while EF and LV volumes were calculated using an automatic algorithm (QGS). The post-stress and rest ratio were determined for both end-diastolic (EDV) and end-systolic volume (ESV), while the post-stress LVEF change was calculated subtracting rest-EF from stress-EF.. 84/497 pts. showed rest EF < 40%, and 15/84 (18%) experienced a cardiac event (3 cardiac deaths, 1 infarction, 3 hospitalized angina and 9 late revascularizations). The perfusion and functional parameters were not significantly more compromised in pts. with cardiac events compared with pts. without events. Post-stress ESV was the only index significantly higher in pts. with low EF and events compared with pts. with low EF without events (150 +/- 72 ml vs. 123 +/- 53 ml, P = 0.02). Univariate Cox analysis of clinical, perfusion and functional data showed that the best predictor of cardiac events was stress-ESV (score 6.5, P = 0.01), followed by rest-ESV, rest-EDV, stress-EDV and stress-LVEF. Multivariate analysis demonstrated that the addition of stress-ESV to stress-EF, yielded a significant increase in the global chi2 in the prediction of hard events (cardiac death/infarction) (score 4.634, P = 0.03).. In patients with depressed LVEF, stress-ESV was the only independent predictor of long-term outcome.

Topics: Adult; Aged; Aged, 80 and over; Cardiac Output; Coronary Angiography; Coronary Artery Disease; Exercise Test; Follow-Up Studies; Gated Blood-Pool Imaging; Heart Ventricles; Humans; Magnetic Resonance Angiography; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Stroke Volume; Survival Analysis

Software packages are widely used for quantification of myocardial perfusion defects. The quantification is used to assist the physician in his/her interpretation of the study. The purpose of this study was to compare the quantification of reversible perfusion defects by three different commercially available software packages. We included 50 consecutive patients who underwent myocardial perfusion single-photon emission tomography (SPET) with a 2-day technetium-99m tetrofosmin protocol. Two experienced technologists processed the studies using the following three software packages: Cedars Quantitative Perfusion SPECT, Emory Cardiac Toolbox and 4D-MSPECT. The same sets of short axis slices were used as input to all three software packages. Myocardial uptake was scored in 20 segments for both the rest and the stress studies. The summed difference score (SDS) was calculated for each patient and the SDS values were classified into: normal (< 4), mildly abnormal (4-8), moderately abnormal (9-13), and severely abnormal (> 13). All three software packages were in agreement that 21 patients had a normal SDS, four patients had a mildly abnormal SDS and one patient had a severely abnormal SDS. In the remaining 24 patients (48%) there was disagreement between the software packages regarding SDS classification. A difference in classification of more than one step between the highest and lowest scores, for example from normal to moderately abnormal or from mildly to severely abnormal, was found in six of these 24 patients. Widely used software packages commonly differ in their quantification of myocardial perfusion defects. The interpreting physician should be aware of these differences when using scoring systems.

Topics: Adult; Aged; Aged, 80 and over; Algorithms; Coronary Artery Disease; Female; Humans; Image Interpretation, Computer-Assisted; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Software; Software Validation; Tomography, Emission-Computed, Single-Photon

Basic and clinical studies have indicated that 15-(p-[(123)I] iodophenyl)-3-(R, S) methylpentadecanoic acid (BMIPP) single photon emission computed tomography (SPECT) can identify ischemic myocardium without evidence of myocardial infarction by the regional decline of tracer uptake. The present study compared BMIPP SPECT with rest-stress myocardial perfusion imaging (MPI) findings and coronary angiography (CAG) in 150 patients with acute chest pain.. Patients with acute chest pain who underwent all of the following tests were selected: MPI at rest-stress, BMIPP SPECT at rest and CAG. Organic coronary artery stenosis (>or=75%) was observed in 46 patients, 27 patients had total or subtotal coronary occlusion by spasm in the spasm provocation test on CAG and the remaining 77 patients had no significant coronary artery stenosis or spasm. The sensitivity of BMIPP at rest to detect organic stenosis was significantly higher (54%) than that of rest-MPI (33%, p<0.005), but lower than that of stress-MPI (76%, p=0.05). The sensitivity of BMIPP at rest to detect spasm was significantly higher (63%) than that of both rest-MPI (15%; p<0.001) and stress-MPI (19%; p<0.001). Overall, the sensitivity of BMIPP at rest to detect both organic stenosis and spasm was significantly higher (58%) than that of rest-MPI (26%; p<0.001), despite having no significance with that of stress-MPI (55%). The specificity was not significantly different among the three imaging techniques.. Resting BMIPP SPECT is an alternative method to stress MPI for identifying patients with not only organic stenosis but also spasm without the need for a stress examination.

Topics: Aged; Chest Pain; Coronary Angiography; Coronary Artery Disease; Fatty Acids; Female; Humans; Iodine Radioisotopes; Iodobenzenes; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon

In order to compare the diagnostic ability of pulsed tissue Doppler and myocardial perfusion Single Photon Emission Computed Tomography (SPECT) in patients with a history of unstable coronary artery disease, CAD, 26 patients, 22 men and four women, age 47-76 years, were investigated in a prospective study, 5-10 day after an episode of unstable angina. Tissue Doppler and two-dimensional echocardiography were performed during dobutamine stress testing and myocardial scintigraphy after bicycle exercise and at rest. Patients with a normal SPECT had higher peak systolic velocity during dobutamine infusion, 18.9 +/- 4.1 cm s(-1), than patients with ischaemia, 12.2 +/- 3.8 cm s(-1) (P<0.001) or scar, 8.8 +/- 3.0 cm s(-1) (P<0.01). In a territorial analysis the difference in peak systolic velocity between areas with a normal and abnormal SPECT was less apparent. Failure to achieve >/=13 cm s(-1) in mean-peak systolic velocity was the most accurate criterion for detection of significant CAD on SPECT. We conclude that pulsed tissue Doppler can be used for objective quantification of left ventricular wall motion during dobutamine stress testing and for identification of patients with CAD on SPECT but not for identification of regional ischaemia.

Topics: Aged; Coronary Artery Disease; Dobutamine; Echocardiography, Doppler, Pulsed; Echocardiography, Stress; Exercise Test; Feasibility Studies; Female; Humans; Image Interpretation, Computer-Assisted; Male; Middle Aged; Myocardial Ischemia; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

Myocardial perfusion imaging with (99m)Tc-tetrofosmin is based on the assumption of a linear correlation between myocardial blood flow (MBF) and tracer uptake. However, it is known that (99m)Tc-tetrofosmin uptake is directly related to energy-dependent transport processes, such as Na(+)/H(+) ion channel activity, as well as cellular and mitochondrial membrane potentials. Therefore, cellular alterations that affect these energy-dependent transport processes ought to influence (99m)Tc-tetrofosmin uptake independently of blood flow. Because metabolism ((18)F-FDG)-perfusion ((99m)Tc-tetrofosmin) mismatch myocardium (MPMM) reflects impaired but viable myocardium showing cellular alterations, MPMM was chosen to quantify the blood flow-independent effect of cellular alterations on (99m)Tc-tetrofosmin uptake. Therefore, we compared microsphere-equivalent MBF (MBF_micr; (15)O-water PET) and (99m)Tc-tetrofosmin uptake in MPMM and in "normal" myocardium.. Forty-two patients with severe coronary artery disease, referred for myocardial viability diagnostics, were examined using (18)F-FDG PET and (99m)Tc-tetrofosmin perfusion SPECT. Relative (18)F-FDG and (99m)Tc-tetrofosmin uptake values were calculated using 18 segments per patient. Normal myocardium and MPMM myocardium were classified using a previously validated (99m)Tc-tetrofosmin SPECT/(18)F-FDG PET score. In addition, (15)O-water PET was performed to assess kinetic-modeled MBF (MBF_kin), the water-perfusable tissue fraction (PTF), and the resulting MBF_micr (MBF_kin x PTF), which is comparable to tracer uptake values. (99m)Tc-tetrofosmin uptake and MBF_micr values were calculated for all normal and MPMM segments and averaged within their respective classifications.. Mean relative (99m)Tc-tetrofosmin uptake was 86% +/- 1% in normal myocardium and 56% +/- 1% in MPMM, showing a significant difference (P < 0.001), as was expected from the classification. Contrary to these findings, mean MBF_micr in MPMM myocardium was 0.60 +/- 0.03 mL x min(-1) x mL(-1), which did not significantly differ from normal myocardium (0.64 +/- 0.01 mL x min(-1) x mL(-1)). All values are given as mean +/- SEM.. Differences between reduced (99m)Tc-tetrofosmin uptake and the unchanged MBF_micr in MPMM myocardium suggest that the pathophysiologic basis of MPMM is not a blood flow reduction but cellular alterations that affect uptake and retention of (99m)Tc-tetrofosmin independently of blood flow. Therefore, it seems that perfusion deficits in MPMM myocardium are greatly overestimated by (99m)Tc-tetrofosmin and that it tends to give false-positive findings.

Topics: Adult; Aged; Coronary Artery Disease; Coronary Circulation; Female; Fluorodeoxyglucose F18; Heart; Humans; Male; Microspheres; Middle Aged; Myocardium; Organophosphorus Compounds; Organotechnetium Compounds; Oxygen Isotopes; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Tissue Distribution; Tomography, Emission-Computed; Tomography, Emission-Computed, Single-Photon; Water

Currently, with the rapidly increasing number of patients with heart failure due to chronic coronary artery disease, the need for viability studies to guide treatment in these patients is increasing. The most accurate method for viability assessment is metabolic imaging with (18)F-FDG with PET or SPECT. To obtain excellent image quality in all patients, the (18)F-FDG studies should be performed during hyperinsulinemic euglycemic clamping. However, this approach is time-consuming and is not feasible in busy nuclear medicine laboratories. Recently, the use of a nicotinic acid derivative, acipimox, has been suggested, but limited data are available on the image quality of the (18)F-FDG studies using this approach.. We evaluated the feasibility and image quality of (18)F-FDG SPECT (with dual-isotope simultaneous acquisition (DISA) using (99m)Tc-tetrofosmin to assess perfusion) after acipimox administration in 50 nondiabetic patients. The image quality of both (18)F-FDG and (99m)Tc-tetrofosmin was assessed visually and quantitatively using myocardium-to-blood-pool (M/B) ratios as a measure of target-to-background ratio. The image quality and diagnostic value of DISA (99m)Tc-tetrofosmin SPECT was compared with standard (99m)Tc-tetrofosmin SPECT at baseline.. After acipimox administration, the plasma levels of free fatty acids were extremely low (68 +/- 89 nmol/L). No severe side effects were observed, only paroxysmal flushing. The (18)F-FDG image quality was good in 46 patients (92%) and moderate but still interpretable in the other 4 patients (8%). The clinical information of the baseline (99m)Tc-tetrofosmin SPECT was retained in the DISA (99m)Tc-tetrofosmin SPECT images because we did observe no substantial fill-in of perfusion defects by high (18)F-FDG uptake in the same segment.. Cardiac (18)F-FDG SPECT after acipimox is safe and resulted consistently in good image quality; this simple approach may be the method of choice for routine cardiac metabolic imaging.

Topics: Administration, Oral; Chronic Disease; Coronary Artery Disease; Echocardiography; Feasibility Studies; Female; Fluorodeoxyglucose F18; Heart; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Pyrazines; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

Previous studies have demonstrated that myocardial perfusion imaging using 99mTc-tetrofosmin at rest allows viability assessment similar to that obtained with 201Tl imaging and 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET). The simultaneous assessment of perfusion and regional function is now available by quantitative gated myocardial perfusion single-photon emission computed tomography (SPECT). This study was designed to evaluate the utility of quantitative values of wall motion and wall thickening, calculated by quantitative gated myocardial perfusion SPECT, for the prediction of functional recovery after coronary bypass grafting (CABG). Fifty-six patients with coronary artery disease scheduled for CABG were included prospectively. All patients underwent 99mTc-tetrofosmin gated SPECT imaging at rest preoperatively and 3 months after CABG. The myocardium was divided into nine segments and the average quantitative values of regional perfusion (percentage uptake) (%), wall motion (mm) and wall thickening (%) were determined automatically using quantitative gated SPECT (QGS) software. The wall motion score was defined visually using a four-point scale (0, normal; 3, akinesis), and segments with severe asynergy (score of 2 or 3) with patent grafts were assessed. Of 77 segments with severe asynergy, 56 segments showed improved wall motion and 21 segments did not improve after CABG. The area under the receiver operating characteristic curve of wall thickening for the prediction of functional recovery was significantly higher (0.92) than that of the percentage uptake (0.77, P<0.017) or wall motion (0.60, P<0.0001). When each analysis used the optimal threshold, the wall thickening analysis (>or=10%) had a sensitivity of 95% and a specificity of 81%. These values tended to be higher than those of the percentage uptake (sensitivity, 86%; specificity, 67%). The wall motion analysis (>or=1.5 mm) had a significantly lower sensitivity of 75% and specificity of 43% than the wall thickening analysis (P=0.0038 and P=0.011, respectively). The results indicate that wall thickening, calculated by QGS software, may be more useful than regional perfusion or wall motion analysis for the prediction of functional recovery after CABG. The areas of asynergy with relatively preserved wall thickening may have the potential for improved function despite severely decreased perfusion.

Topics: Aged; Coronary Artery Bypass; Coronary Artery Disease; Female; Gated Blood-Pool Imaging; Humans; Image Interpretation, Computer-Assisted; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Radiopharmaceuticals; Reproducibility of Results; Risk Assessment; Sensitivity and Specificity; Tomography, Emission-Computed, Single-Photon; Treatment Outcome; Ventricular Dysfunction, Left

The aim of this study was to assess the influence of incremental nitroglycerin infusion (NTG+Inf) on the myocardial uptake of 99mTc-tetrofosmin (TF) in order to determine whether nitrates enhance the detection of viable myocardium with TF in patients with coronary artery disease (CAD) and left ventricular dysfunction. Fifty patients (39 males, 11 females; 54 +/- 11 years) with previous myocardial infarction and left ventricular dysfunction, who had been referred for coronary revascularization procedures, were studied. Myocardial single-photon emission tomography (SPET) images were obtained 1 h after injection of 750 MBq TF at baseline and after NTG+Inf, using a 2 day protocol. NTG+Inf was performed starting at 0.4 microg x kg(-1) x min(-1), with equal increments every 5 min up to 2 microg x kg(-1) x min(-1). Within 1 week of the TF study, rest-redistribution (R-RD) 201Tl SPET was performed after the injection of 111 MBq 201Tl. For each study, quantitative analysis was performed in 17 segments. Viability was defined as the presence of tracer uptake of > 50% of the peak activity on baseline studies or reversibility. There was significant correlation between quantitative regional RD 201Tl activity and TF activity after NTG+Inf (r = 0.90, P < 0.001). Of the 131 segments with severely reduced tracer uptake on resting TF images, 34 (26%) were reversible, showing increased tracer uptake after NTG+Inf (from 41%+/-7% to 57%+/-12% of peak activity; P < 0.001). All reversible segments after NTG+Inf had viability criteria on 201Tl studies. There was 95% concordance between TF with NTG+Inf and RD 201Tl imaging with regard to the presence of myocardial viability. We conclude that TF imaging with incremental NTG+Inf improves the detection of ischaemic but viable myocardium, correlating with the viability criteria observed on 201Tl studies. When the advantages of TF imaging are considered, rest TF imaging with NTG+Inf may be a practical diagnostic protocol in patients with CAD and left ventricular dysfunction who are being considered for revascularization.

Topics: Adult; Aged; Coronary Artery Disease; Female; Humans; Infusions, Intravenous; Male; Middle Aged; Myocardial Infarction; Myocardial Ischemia; Nitroglycerin; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Severity of Illness Index; Statistics as Topic; Thallium; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

Attenuation artefacts decrease the specificity of myocardial perfusion single-photon emission computed tomography (SPECT). In this paper, the results of a prospective study evaluating the clinical applicability of attenuation and scatter correction in myocardial perfusion SPECT are presented. Of 607 patients in whom post-stress 99mTc-tetrofosmin myocardial perfusion SPECT was performed due to suspicion of coronary artery disease, 99 also underwent coronary angiography (CAG). A simultaneous emission/transmission acquisition was performed. A multiple linear array of 153Gd sources and four independent energy windows were used for attenuation and scatter correction. A blind separate analysis of non-corrected (NC) and attenuation- and scatter-corrected (AC-SC) images was performed with scores of zero (no uptake) to three (normal uptake). The final diagnosis was based on CAG findings, and stenoses of > or =70% were considered to be significant. NC images had a sensitivity of 92% and a specificity of 46%. In AC-SC images, the sensitivity decreased to 76%, but the specificity increased to 71%. The decrease in the sensitivity of AC-SC images was observed in all three coronary regions. Attenuation and scatter correction increased the specificity in the right coronary region, but decreased the specificity in the left anterior descending coronary region. In 13 of the 99 patients, AC-SC images showed false positive findings due to count deficiency in the anterior wall with normal CAG. The size of perfusion defects was decreased in AC-SC images (from 5.01 +/- 2.74 to 3.15 +/- 2.50 segments). The severity of perfusion defects was higher in NC (1.10 +/- 0.60) than in AC-SC (1.28 +/- 0.56) images. The combined evaluation of NC and AC-SC images was in agreement with the CAG findings in 79% of patients. It can be concluded that, when compared with NC images, AC-SC images improved the specificity in the right coronary region and decreased the sensitivity in all three coronary regions. Attenuation and scatter correction may generate anterior wall defects with normal CAG. The analysis of AC-SC images cannot be used alone for the diagnosis of coronary artery disease. In the clinical setting, combined NC and AC-SC images are recommended for the evaluation of post-stress myocardial perfusion SPECT.

Topics: Adult; Aged; Aged, 80 and over; Algorithms; Artifacts; Coronary Artery Disease; Coronary Vessels; Female; Heart; Humans; Image Enhancement; Image Interpretation, Computer-Assisted; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Prospective Studies; Radiopharmaceuticals; Reproducibility of Results; Scattering, Radiation; Sensitivity and Specificity; Tomography, Emission-Computed, Single-Photon

There are currently insufficient data to indicate a role for stress myocardial perfusion imaging as a prognostic tool in hypertensive patients.. To assess the incremental value of stress myocardial perfusion imaging for the prediction of cardiac death in hypertensive patients relative to clinical data.. We studied 601 hypertensive patients (aged 59 +/- 10 years, 387 men) who underwent exercise bicycle or dobutamine (up to 40 microg/kg per min) stress technetium-99m tetrofosmin single photon emission computed tomography (SPECT) for evaluation of coronary artery disease.. Cardiac death during follow-up. RESULTS; An abnormal scan (reversible or fixed perfusion abnormalities) was detected in 293 (49%) patients (134 had reversible abnormalities). During a mean follow-up period of 3.1 +/- 1.3 years, 109 (18%) patients died; of whom, 42 patients (39%) died due to cardiac causes. Independent predictors of cardiac death were age [hazard ratio = 1.04, 95% confidence interval (CI) 1.01-1.08], history of previous myocardial infarction (hazard ratio = 2, CI 1.1-3.7), stress rate-pressure product (hazard ratio = 0.94, CI 0.87-0.98) and abnormal scan (hazard ratio = 4.7 CI 1.9-11.4). Both reversible and fixed abnormalities were predictive of death. The annual cardiac death rate was 5.3% in patients with an abnormal and 0.5% in patients with a normal perfusion scan.. Stress technetium-99m tetrofosmin myocardial perfusion imaging provides prognostic information incremental to clinical data for the prediction of cardiac death in hypertensive patients with known or suspected coronary artery disease.

Topics: Adrenergic beta-Agonists; Aged; Coronary Artery Disease; Death; Dobutamine; Exercise Test; Female; Follow-Up Studies; Humans; Hypertension; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Predictive Value of Tests; Prognosis; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon

We studied 24 patients with severe coronary artery lesions to assess myocardial perfusion and left ventricular contractile reserve simultaneously using low-dose dobutamine quantitative electrocardiographically gated single-photon emission computed tomography in patients with Kawasaki disease. Low-dose dobutamine infusion was started after an injection of technetium-99m tetrofosmin at rest. Myocardial contractile reserve was evaluated using the post-stress and low-dose dobutamine images, and myocardial perfusion was evaluated using the stress and rest images. Quantitative electrocardiographically gated single-photon emission computed tomography during low-dose dobutamine infusion is a useful and safe method for the combined evaluation of myocardial contractile reserve and myocardial perfusion.

Topics: Adolescent; Adult; Cardiotonic Agents; Child; Child, Preschool; Coronary Artery Disease; Dobutamine; Female; Humans; Infusions, Intravenous; Injections, Intravenous; Male; Mucocutaneous Lymph Node Syndrome; Myocardial Contraction; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon; Ventricular Function, Left

The purpose of this study was to compare the performance of automatic detection of coronary artery disease (CAD) with that of expert observers. A male and female normal image template was constructed from normal stress technetium-99m single photon emission computed tomography (SPECT) studies. Mean and standard deviation images for each sex were created by registering normal studies to a standard shape and position. The test group consisted of 104 patients who had been routinely referred for SPECT and angiography. The gold standard for CAD was defined by angiography. The test group studies were registered to the respective templates and the Z-score was calculated for each voxel. Voxels with a Z-score greater than 5 indicated the presence of CAD. The performance of this method and that of three observers were compared by continuous receiver operating characteristic (CROC) analysis. The overall sensitivity and specificity for automatic detection were 73% and 92%, respectively. The area (Az) under the CROC curve (+/-1 SE) for automatic detection of CAD was 0.88+/-0.06. There was no statistically significant difference between the performances of the three observers in terms of Az and that of automatic detection (P> or =0.25, univariate Z-score test). The use of this automated statistical mapping approach shows a performance comparable with experienced observers, but avoids inter-observer and intra-observer variability.

Topics: Algorithms; Coronary Artery Disease; Female; Heart; Humans; Image Enhancement; Image Interpretation, Computer-Assisted; Male; Middle Aged; Observer Variation; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; ROC Curve; Sensitivity and Specificity; Single-Blind Method; Subtraction Technique; Tomography, Emission-Computed, Single-Photon

Left ventricular function is an important prognostic indicator in patients with coronary artery disease. The electrocardiogram gated, myocardial, single photon emission tomography (SPECT) program is coming into wide use. This program permits measurement of end diastolic volume, end systolic volume, and ejection fraction. This study was designed to show whether the measurement of ejection fraction by using (99c)Tc tetrofosmin gated SPECT at rest could give additional information to the interpretation of perfusion. Exercise 99mTc tetrofosmin SPECT and gated (99c)Tc tetrofosmin SPECT at rest were performed in 33 patients with or suspected of having coronary artery disease. Left ventricular ejection fraction was calculated from reconstructed gated SPECT at rest with a software quantitative gated SPECT. The results showed a poor correlation between segmental ejection fraction and segmental perfusion in stress and rest. There was an increasing probability of reversibility as the ejection fraction increased, while there was a greater chance of a fixed defect as the ejection fraction decreased. It is concluded that gated SPECT using (99c)Tc tetrofosmin provides clinically satisfactory functional data that, in combination with the perfusion information, will improve diagnostic and prognostic accuracy without an increase in cost or radiation dose to patients.

Topics: Adult; Aged; Coronary Artery Disease; Coronary Circulation; Exercise Test; Female; Gated Blood-Pool Imaging; Heart Ventricles; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Statistics as Topic; Stroke Volume; Tissue Distribution; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

Nitroglycerin (Ntg) is known to increase blood flow to the hypoperfused myocardial area and thus to reduce regional ischaemia of the heart muscle in coronary artery disease (CAD). The aim of this study was to assess the effect of a therapeutic dose of Ntg on 99mTc-Tetrofosmin uptake defects occurring in patients (pts) with CAD in myocardial SPECT at rest. The study population comprised 34 pts with CAD. All subjects underwent myocardial perfusion SPECT at rest, using 2-day, protocol. On the first day 99mTc-Tetrofosmin was injected in baseline conditions and on the second day, after sublingual administration of 0.5 mg Ntg. The baseline examination revealed altogether 78 Tetrofosmin uptake defects in all 34 pts. The SPECT after Ntg showed improved tracer uptake in 33/78 perfusion defects in 18/34 pts, no change in 29/78 defects in 7/34 cases and more reduced tracer uptake in 16/78 defects in 9/34 pts. No explicit, significant relationship was found between 99mTc-Tetrofosmin uptake changes after Ntg on the one hand and the number of involved vessels, degree of coronary artery stenosis, history of myocardial infarction and LV global and regional function on the other. It is concluded that sublinqual administration of Ntg may result in improvement as well as in deterioration of regional perfusion defects, assessed with 99mTc-Tetrofosmin in CAD. The relationships between Ntg-augmented changes in uptake defects of this tracer on the one hand and conditions of the LV function and severity of heart muscle perfusion abnormalities on the other are unclear and should be verified on a larger study population.

Topics: Adult; Aged; Coronary Angiography; Coronary Artery Disease; Female; Heart Ventricles; Humans; Image Enhancement; Male; Middle Aged; Myocardium; Nitroglycerin; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon; Vasodilator Agents; Ventricular Dysfunction, Left

The clinical feasibility of both dual-isotope single photon emission tomography (SPET) and gated SPET have been described. The present study evaluates the feasibility of combining gated SPET with exercise 201Tl/rest 99mTc-tetrofosmin dual-isotope SPET corrected for scatter. Ninety-one patients with known or suspected coronary artery disease underwent cardiac catheterization and coronary angiography. Twenty-nine of them underwent exercise 201Tl/rest 99mTc-tetrofosmin dual-isotope SPET with a second 201Tl injection 3 h after the initial 201Tl injection (protocol 1). We then segregated a Bull's eye polar map into three coronary artery territories and quantified the relative regional uptake. The remaining 62 patients underwent exercise 201Tl/rest 99mTc-tetrofosmin dual-isotope SPET combined with gated SPET. We visually evaluated exercise and rest images from the three coronary artery territories. Left ventricular (LV) function was assessed globally by means of the LV ejection fraction and regionally by means of visual scoring analysis, compared with left ventriculography (LVG). The correlation between rest 99mTc-tetrofosmin and 201Tl reinjection images in 87 areas of coronary artery territory (r=0.89, P<0.01) and in 13 infarcted areas (r =0.94, P<0.01) was very close in protocol 1. The overall values for vessel-related sensitivity, specificity and accuracy were 88%, 79% and 82%, respectively, in protocol 2. The correlation between gated SPET and LVG was significant and linear with respect to the LV ejection fraction (r=0.77, P<0.01). The wall motion score from visual evaluation in gated SPET revealed a close overall agreement with LVG (concordance rate, 88%; kappa, 0.670). Exercise 201Tl/rest 99mTc-tetrofosmin dual-isotope SPET with scatter correction for assessing the coronary artery disease offers excellent diagnostic accuracy and the additional gated SPET provides useful information about LV function similar to that for LVG. This sequential protocol requires only 2 h to generate much useful clinical information.

Topics: Aged; Cardiac Catheterization; Coronary Artery Disease; Coronary Circulation; Feasibility Studies; Female; Gated Blood-Pool Imaging; Heart; Humans; Male; Middle Aged; Myocardial Ischemia; Organophosphorus Compounds; Organotechnetium Compounds; Perfusion; Radiopharmaceuticals; Stroke Volume; Thallium Radioisotopes; Ventricular Function, Left

In myocardial perfusion imaging, multiple-vessel involvement of coronary artery disease (CAD) sometimes makes diagnosis difficult. Transient left ventricular (LV) dilatation on Tl-201 myocardial SPECT is a useful finding that enables the clinician to identify patients with multiple-vessel disease. The aim of this study was to confirm the utility of measuring transient LV dilatation for the detection of multiple-vessel CAD in exercise Tc-99m tetrofosmin myocardial SPECT. The participants were 55 CAD patients and 20 controls who underwent Tc-99m tetrofosmin myocardial SPECT exercise and resting imaging. During exercise, 370 MBq (10 mCi) Tc-99m tetrofosmin was injected. Exercise images were obtained 30 minutes after injection. At 210 minutes after injection, 740 MBq (20 mCi) Tc-99m tetrofosmin was administered intravenously. The rest SPECT images were acquired 30 minutes later. Thirty-six radii at every 10 degrees were generated from the center of short-axis images. An area surrounded by 36 maximal points of the myocardial Tc-99m tetrofosmin counts on each radius was calculated for exercise and rest images. The area surrounded by the 36 maximal points in the same slice of the exercise and rest images was assigned the variables A (Ex) and A(R), respectively. The transient dilatation index (TDI) of the left ventricle was calculated using the formula mean A (Ex)/A(R) in the apical, middle, and basal myocardial short-axis images. In the controls, the TDI was 0.970 +/- 0.021. In patients with CAD, the TDIs of one-vessel disease, two-vessel disease, and three-vessel disease were 1.034 +/- 0.032, 1.093 +/- 0.046, and 1.131 +/- 0.076, respectively. The TDIs were significantly greater in patients who had more occluded coronary arteries (P < 0.01). If the mean + 2SD of the TDI (1.012) in controls were assumed to be the normal upper limit, the sensitivity, specificity, and accuracy of this method in detecting two-vessel or three-vessel disease would be 91.4%, 76.9%, and 84%, respectively. The TDI is a useful index for evaluating subendocardial ischemia non-invasively and detecting multiple-vessel disease clinically.

Topics: Coronary Angiography; Coronary Artery Disease; Dilatation, Pathologic; Exercise; Female; Hemodynamics; Humans; Hypertrophy, Left Ventricular; Image Interpretation, Computer-Assisted; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Rest; Sensitivity and Specificity; Signal Processing, Computer-Assisted; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left; Ventricular Remodeling

By evaluating concordant or discordant perfusion and systolic wall thickening patterns, resting quantitative electrocardiographic (ECG) gated single-photon emission tomography (SPET) can identify various myocardial pathological conditions with different functional recovery after revascularisation therapy. However, no data are available on the ability of this methodology to predict regional functional recovery after primary percutaneous transluminal coronary angioplasty (PTCA). This study evaluated whether single-injection ECG gated SPET imaging performed at rest with 99mTc-tetrofosmin early after successful PTCA can predict recovery of regional wall motion. ECG gated SPET was performed 3 days and 3 weeks after successful PTCA in 26 patients. Regional functional parameters were automatically calculated with a 20-segment model on the day 3 image, and segments with perfusion/thickening mismatch were defined as showing preserved perfusion (>55% uptake on the end-diastolic image: mean-standard deviation of the normal value) without systolic wall thickening (mean-standard deviation of the normal value). On the third day, the regional wall motion score of 37 mismatched segments (3.8+/-2.1) was significantly lower than that of 41 matched normal segments (6.0+/-2.9), but was significantly higher than that of 108 matched abnormal segments (1.4+/-1.9, both P<0.01). At 3 weeks after acute MI, the regional wall motion score of mismatched segments (6.4+/-3.9) improved to the level of matched normal segments (7.1+/-3.0) and was significantly higher than that of matched abnormal segments (2.5+/-3.0, P<0.01). Absolute change in the regional wall motion score (3 days to 3 weeks) of mismatched segments (2.6+/-3.5) was significantly greater than that in the regional wall motion score of matched normal segments and matched abnormal segments (1.1+/-1.3 and 1.2+/-2.6, respectively, both P<0.05). Twenty-seven of 37 segments (73%) with perfusion/thickening mismatch showed significant improvement in regional wall motion, whereas improvement in regional wall motion was observed in 22 of 108 segments (20%) with matched abnormal segments and 6 of 41 segments (15%) with matched normal segments. Segments with perfusion/thickening mismatch had a significantly higher incidence of regional functional improvement than did matched abnormal or matched normal segments (chi2=42.3, P<0.01). Thus, by estimating both perfusion and wall thickening, single-injection resting ECG gated SPET imaging w

Topics: Analysis of Variance; Angioplasty, Balloon, Coronary; Coronary Artery Disease; Coronary Circulation; Female; Gated Blood-Pool Imaging; Heart; Humans; Male; Middle Aged; Myocardial Infarction; Myocardial Reperfusion; Organophosphorus Compounds; Organotechnetium Compounds; Predictive Value of Tests; Reproducibility of Results; Sensitivity and Specificity; Systole

This study was designed to assess the value of gated SPECT Tc-99m-tetrofosmin (TF) wall thickening (WT) in addition to TF exercise (Ex)/rest myocardial SPECT, in comparison with F-18 fluorodeoxyglucose (FDG)-PET.. The study population consisted of 33 patients with old myocardial infarction (27 men and 6 women; mean age, 62 +/- 8 years old). All patients underwent Ex/rest TF SPECT and glucose loading FDG-PET. Polar map images of Ex/rest TF were generated and divided into 24 segments for further analysis. We classified LV segments according to the exercise-rest perfusion scintigraphy. LV segments with less than 70% of the maximum TF activity on the exercise image were defined as stress-induced defects. Among these, the segments whose TF activity increased by 10% from exercise to rest images or exceeded 70% of the maximum uptake were defined as reversible (viable) defects. The remaining defects on the rest image were irreversible (non-viable) defect segments, and were considered for viability study on the basis of %WT. %WT was calculated according to the standard method: [(counts ES - counts ED)/counts ED] x 100. A viable segment on gated SPECT was defined as a segment whose %WT exceeded the lower limit of the normal value (mean - SD). PET viability was defined as FDG uptake exceeding 50% of the maximum count.. Among the 792 segments evaluated in the 33 patients studied, there were 689 PET viable segments. Of the 689 segments analyzed, 198 (29%) were identified as having defects on Ex images. Among these defects, 55 (8%) were reversible or partially reversible, as evidenced by rest images, and 143 (21%) were irreversible. Of the irreversible segments on Ex/rest images, 106 (15%) demonstrated no apparent WT by gated TF SPECT, whereas 37 (6%) segments with irreversible defects did have apparent WT. Overall, the sensitivity of Ex/rest TF perfusion imaging was 79%. Sensitivity was improved from 79% to 85% by combining %WT and perfusion data, but specificity was reduced from 70% to 56%.. %WT evaluated from gated TF imaging enhanced myocardial viability assessment in comparison with FDG-PET.

Topics: Aged; Cell Survival; Coronary Artery Disease; Exercise Test; Female; Fluorodeoxyglucose F18; Gated Blood-Pool Imaging; Heart; Humans; Hypertrophy, Left Ventricular; Male; Middle Aged; Myocardial Infarction; Myocardium; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity

Topics: Artifacts; Breast; Breast Neoplasms; Coronary Artery Disease; False Positive Reactions; Female; Humans; Image Processing, Computer-Assisted; Male; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Phantoms, Imaging; Prognosis; Reproducibility of Results; Technetium Tc 99m Sestamibi; Tomography, Emission-Computed, Single-Photon

The global rest MBF was 0.76 ± 0.19 mL/min/gr by PET and 0.76 ± 0.24 by AC-CZT (P = NS) and 1.14 ± 0.4 by NAC-CZT (P < 0.001 vs PET and AC-CZT). Stress MBF was higher when measured by PET than AC-CZT (1.87 ± 0.45 vs 1.62 ± 0.68 mL/min/gr, P < 0.0008), but lower than NAC-CZT (2.36 ± 1.1, P < 0.0003). The MBF reserve ratio (MFR) was higher by PET than AC-CZT (2.52 ± 0.56 vs 2.22 ± 1 (P < 0.009) and NAC-CZT (2.18 ± 1.0, P < 0.004). Linear regression was better between PET (MFR and stress MBF) and AC-CZT than between PET and NAC-CZT. ROC curve analysis showed the significant ability of AC-CZT to predict MFR < 2 and stress MBF < 1.7 (AUC = 0.75 and 0.82 respectively) and to differentiate between normal and CAD patients (AUC = 0.747 and 0.892 for MFR and stress MBF, respectively).. Our data show a reasonable correlation between MBF and MFR measured by N

Topics: Adult; Aged; Aged, 80 and over; Ammonia; Cadmium; Coronary Artery Disease; Coronary Circulation; Female; Fractional Flow Reserve, Myocardial; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Nitrogen Radioisotopes; Organophosphorus Compounds; Organotechnetium Compounds; Positron Emission Tomography Computed Tomography; Predictive Value of Tests; Radiopharmaceuticals; ROC Curve; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

Measurement of myocardial blood flow (MBF) with single photon emission computed tomography (SPECT) is feasible using cardiac cameras with solid-state detectors. SPECT MBF has been shown to be accurate when compared with positron emission tomography MBF measured in the same patients. However, the value of a test result applied to an individual patient depends strongly on the precision or repeatability of the test. The purpose of our study is to measure the precision of SPECT MBF measurements using. SPECT MBF was measured in 30 patients and repeated at a mean interval of 18 days. MBF was evaluated from images with and without attenuation correction based on a separately acquired CT scan. The dynamic images were processed independently by 2 operators using in-house kinetic analysis software that applied a 1-tissue-compartment model. The K1 rate constant was converted to MBF using previously determined extraction fraction corrections. Correction for patient body motion was applied manually.. The average coefficient of variation (COV) in the differences between the 2 MBF measurements was between 28% and 31%. The interobserver COV was between 11% and 15%. Myocardial flow reserve is the ratio of MBF measured at stress and rest, and the COV is correspondingly higher. The COV for the difference in repeated myocardial flow reserve was 33% to 38%, whereas the interobserver COV was 13% to 22%.. The COV for the difference in SPECT MBF measurements obtained on separate days is 28% to 31%. The corresponding COV for myocardial flow reserve is 33% to 38%.

Topics: Aged; Coronary Artery Disease; Coronary Circulation; Coronary Vessels; Female; Humans; Male; Organophosphorus Compounds; Organotechnetium Compounds; Predictive Value of Tests; Radiopharmaceuticals; Regional Blood Flow; ROC Curve; Tomography, Emission-Computed, Single-Photon

Attenuation correction using segmentation of scatter and photo-peak window data (SSPAC) enables an evaluation of the attenuation map in a patient-specific manner without additional radiation exposure. We compared the accuracy of SSPAC and non-corrected myocardial perfusion scintigraphy methods for diagnosing the number of stenosed coronary artery vessels.. SSPAC-corrected SPECT myocardial perfusion images exhibit improved accuracy in the detection of the number of stenosed coronary artery vessels, even in patients with multi-vessel CAD.

Topics: Adenosine; Aged; Constriction, Pathologic; Coronary Angiography; Coronary Artery Disease; Coronary Vessels; Electrocardiography; Female; Humans; Image Processing, Computer-Assisted; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Perfusion; Predictive Value of Tests; Reproducibility of Results; Retrospective Studies; Scattering, Radiation; Tomography, Emission-Computed, Single-Photon

Using myocardial perfusion scintigraphy (MPS), an increase in left ventricular (LV) volumes or a decrease in ejection fraction (EF) from rest to stress may be clinically important. The variation in these measures between the low-dose stress acquisition and high-dose rest acquisition in a one-day stress-rest protocol has not been established. We assessed the reproducibility of gated volumetric indices between stress and rest and the normal variation in ungated TID ratio for a one-day stress-rest. Two thousand and one hundred and fifty eight (2158). Gated data were analyzed for 621 patients without inducible hypoperfusion. Mean EF at rest was slightly higher than after stress (62.4% ± 10.3% vs 61.2% ± 10.4%, P < 0.001), and the standard deviation of the difference was 5.2% (95% CI 4.9% to 5.5%). Ungated volumes were available for 992 non-ischaemic patients. The upper 95% CI for TID ratio was 1.23. This increased from 1.20 to 1.37 between the highest and lowest deciles of rest ungated volume.. Using a one-day stress-rest

Topics: Aged; Confidence Intervals; Coronary Artery Disease; Exercise Test; Female; Humans; Male; Middle Aged; Myocardial Ischemia; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Reproducibility of Results; Retrospective Studies; Stroke Volume; Technetium Tc 99m Sestamibi; Tomography, Emission-Computed, Single-Photon; Ventricular Function, Left

We validated a 1-day myocardial perfusion imaging (MPI) protocol using an ultra low-dose(ULD) equal for stress and rest on a cadmium zinc telluride (CZT).. Fifty-six patients underwent a 1-day MPI protocol using a standard (SD) 99mTc-tetrofosmin dose at stress (320 MBq) and rest (960 MBq) with 5 min acquisition time each (SD). Within 2 weeks MPI was repeated using ULD 99mTc-tetrofosmin equal for stress and rest (160 MBq) with 15 min acquisition time each (ULD). All scans were performed on a CZT camera (DNM 570c, GE Healthcare). Background subtraction was applied on the rest MPI of the ULD using P-mod software. Presence and extent of perfusion defect were analysed. Pearson's correlation was used to compare ejection fraction (EF), end diastolic volume (EDV), and end systolic volume (ESV) between both protocols. SD revealed ischaemia in 23, scar in 3, and an equivocal finding in 1 patient, while normal findings were documented in 29 patients. ULD resulted in the following findings: ischaemia 23, scar 3, and 30 normal scans. Congruence of SD and ULD was 22/23 for ischaemia, 3/3 for scar, and 29/29 in normal patients; one patient with ischaemia in SD was classified as scar in ULD. Overall agreement of ULD with SD was 98%. The mean extent of defect was comparable between SD and ULD for the stress (10% vs. 11%, respectively, P = NS) and rest studies (5% vs. 7%, respectively, P = NS). An excellent correlation between SD and ULD was found for EF (r = 0.93), EDV (r = 0.95), and ESV (r = 0.97).. CZT cameras may enable reliable MPI scanning in patients with known or suspected coronary artery disease using protocols with about a factor 4-decrease in radiation dose exposure compared with traditional protocols.

Topics: Aged; Aged, 80 and over; Cadmium; Cardiac-Gated Imaging Techniques; Coronary Artery Disease; Exercise Test; Female; Gamma Cameras; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Prospective Studies; Radiographic Image Interpretation, Computer-Assisted; Radiopharmaceuticals; Rest; Tellurium; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed; Zinc

Topics: Calibration; Coronary Artery Disease; Heart; Humans; Molecular Imaging; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Reproducibility of Results; Technetium Tc 99m Sestamibi; Tomography, Emission-Computed, Single-Photon

We previously validated the use of a data-driven cardiac respiratory-motion (RM) correction method (REGAT) applicable to CZT SPECT myocardial perfusion imaging (MPI). In this study, we adapted the same process used with REGAT for RM to generate data-driven cardiac contraction triggers and corresponding cardiac contraction-gated SPECT studies (GSPECT-DD). We aimed to study its feasibility and compare its performances to GSPECT studies generated with ECG monitor-based triggers (GSPECT-ECG).. We found almost perfect agreement between cardiac contraction triggers generated with data-driven and ECG monitor-based methods. As compared to GSPECT-ECG, GSPECT-DD provided comparable and well-correlated LV global systolic function parameters and similar cine image quality at both stress and rest.. Data-driven cardiac contraction gating using REGAT is feasible with low-dose and high-dose MPI CZT SPECT. It provides GSPECT-DD studies comparable to GSPECT-ECG.

Topics: Aged; Cadmium; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; Coronary Artery Disease; Electrocardiography; Exercise Test; Feasibility Studies; Female; Heart; Heart Ventricles; Humans; Image Processing, Computer-Assisted; Male; Middle Aged; Motion; Myocardial Perfusion Imaging; Nuclear Medicine; Organophosphorus Compounds; Organotechnetium Compounds; Prospective Studies; Radiopharmaceuticals; Respiration; Tellurium; Ventricular Dysfunction, Left; Zinc

Dobutamine stress myocardial perfusion imaging (MPI) is a useful alternative for the evaluation of coronary artery disease (CAD) in elderly patients who are unable to perform an exercise stress test. However, data on the long-term prognostic value of stress MPI in elderly patients are lacking. Therefore, this study evaluated the long-term prognostic value of dobutamine stress MPI in elderly patients unable to perform an exercise test.. The study population consisted of 247 elderly patients (mean age 71 ± 5 years) who underwent dobutamine stress single-photon emission computed tomography (SPECT) MPI. An abnormal SPECT study was defined as the presence of fixed and/or reversible perfusion defects. A summed stress score (SSS) was obtained to estimate the extent and severity of perfusion defects. End points during follow-up were all-cause mortality, cardiac mortality, and nonfatal myocardial infarction (MI).. During a median follow-up of 14 years (range 12-16), 168 (68%) patients died (all-cause mortality), of which 56 (23%) were due to cardiac causes. Nonfatal MI occurred in 19 (8%) patients. Kaplan-Meier survival curves showed that MPI provided optimal risk stratification in patients with normal and abnormal MPI. Multivariable analysis identified an abnormal MPI as a strong significant predictor of all-cause mortality and cardiac events. A multivariable analysis also revealed that a reversible defect and SSS were strong long-term predictors of cardiac mortality and hard cardiac events.. Dobutamine stress

Topics: Aged; Aged, 80 and over; Coronary Artery Disease; Disease Progression; Dobutamine; Exercise Test; Female; Follow-Up Studies; Humans; Kaplan-Meier Estimate; Male; Myocardial Infarction; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Radiopharmaceuticals; Retrospective Studies; Risk Assessment; Risk Factors; Tomography, Emission-Computed, Single-Photon; Treatment Outcome

Background Previous studies revealed a relatively high prevalence of electrocardiographic findings indicative for myocardial ischemia in asymptomatic athletes undergoing pre-participation screening. Myocardial perfusion scintigraphy is generally considered a valuable diagnostic and prognostic modality and often used for further diagnostic evaluation in these subjects. However, data on the diagnostic accuracy of myocardial perfusion scintigraphy in athletes are scarce. Objectives The main purpose of this study was to investigate the positive predictive value of myocardial perfusion scintigraphy for detection of coronary artery disease in asymptomatic athletes with abnormal exercise testing results during pre-participation screening. The secondary aim was to evaluate the prognostic value of myocardial perfusion scintigraphy. Methods Electronic charts of asymptomatic athletes who underwent myocardial perfusion scintigraphy following an abnormal exercise testing were retrospectively reviewed. Myocardial perfusion scintigraphy and exercise testing studies were revised. Athlete characteristics and cardiovascular risk factors were evaluated. Results One hundred and forty-three athletes were included. 29 athletes (20%) showed concordant abnormal exercise testing and myocardial perfusion scintigraphy results. Coronary imaging was performed in 20 of these 29 athletes. Four athletes showed significant coronary artery disease (positive predictive value = 20%). The positive predictive value increased to 33% when athletes were selected who should have undergone exercise testing according to the guideline recommendations. During a mean follow-up interval of 4.7 ± 2.2 years, eight cardiac events occurred. Athletes with an abnormal myocardial perfusion scintigraphy result had a fourfold increased risk at a future cardiac event (2.9%/year versus 0.75%/year, p = 0.031). Conclusions The positive predictive value of myocardial perfusion scintigraphy for the detection of significant coronary artery disease in asymptomatic athletes with a positive exercise testing result is low, even in a selection of athletes with a relatively high cardiovascular risk. Although an abnormal myocardial perfusion scintigraphy result was associated with a fourfold higher annual event rate, the absolute annual event rate in this group was still low. Efforts should be made to develop better diagnostic strategies to evaluate asymptomatic athletes with abnormal exercise testing results during pre-part

Topics: Adult; Athletes; Computed Tomography Angiography; Coronary Angiography; Coronary Artery Disease; Coronary Circulation; Exercise Test; Female; Humans; Male; Middle Aged; Myocardial Ischemia; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Predictive Value of Tests; Prognosis; Radiopharmaceuticals; Reproducibility of Results; Retrospective Studies; Risk Assessment; Risk Factors; Time Factors

The aim of this study was to evaluate the clinical feasibility of simultaneous acquisition of rest (99m)Tc-tetrofosmin/stress (201)Tl dual-isotope single-photon emission computed tomography with a semiconductor gamma camera.. Ninety-four patients with known or suspected coronary artery disease (CAD) were enrolled in the study. First, patients were injected with (99m)Tc-tetrofosmin (296 MBq) for rest imaging, followed by (201)Tl (74 MBq) injection during 6 min of vasodilator stress test. Immediately after the stress test, the patients underwent the first electrocardiogram (ECG)-gated simultaneous acquisition including rest and stress perfusion scans. Patients were brought back for the second simultaneous acquisition for the comparison of ECG-gated wall motion between stress and rest scan 30 min later. Coronary angiography was performed in all the patients within 3 months of this protocol. Sensitivity, specificity and accuracy on a per patient basis to detect significant coronary artery stenosis (≥75%) were 88.6%, 79.2% and 86.2%, respectively. Per coronary vessel, sensitivity, specificity and accuracy were as follows: 84.9%, 80.5% and 83% in the left anterior descending coronary artery; 75%, 93.1% and 86.2% in the left circumflex coronary artery; and 74.2%, 85.7% and 81.9% in the right coronary artery.. Simultaneous acquisition of rest (99m)Tc-tetrofosmin/stress (201)Tl dual-isotope protocol had high diagnostic accuracy for significant CAD. (Circ J 2016; 80: 689-695).

Topics: Aged; Coronary Artery Disease; Coronary Stenosis; Female; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Tomography, Emission-Computed, Single-Photon

A young man underwent Tc-tetrofosmin cardiac SPECT/CT for the evaluation of the 8-month history of exertional dyspnea without chest pain. Tc-tetrofosmin SPECT demonstrated absence of perfusion defects and a mildly decreased uptake in post-stress images, consistent with artifact, in the inferior myocardium. Cardiac catheterization showed a large right and a small left coronary artery opacified retrogradely by right collateral vessels without connections between the left main and the left coronary artery. In patients with anomalous coronary arteries, Tc SPECT can shows absence of perfusion defects, in the presence of a collateral circulation.

Topics: Adult; Coronary Artery Disease; Humans; Male; Organophosphorus Compounds; Organotechnetium Compounds; Tomography, Emission-Computed, Single-Photon

We published a cardiac event risk score (CERS) predicting the risk of major cardiac events (MCEs) within 3 years. The purpose of this study was to verify the prognostic value of the CERS before and after treatment in Japanese patients with coronary artery disease.We retrospectively investigated 612 patients who underwent rest (201)Tl and stress (99m)Tc-tetrofosmin myocardial perfusion single photon emission computed tomography (SPECT) between October 2004 and March 2013 and who had a significant stenosis with ≥ 75% narrowing of the arterial diameter detected by coronary angiography performed after confirmation of ≥ 5% ischemia with the SPECT. The patients underwent treatment including revascularization and medication, and thereafter, were re-evaluated with SPECT during a chronic phase and followed-up to confirm prognosis for ≥ 1 year. The endpoint was the onset of MCEs during the follow-up.During the follow-up (36.7 ± 14.5 months), 50 patients (8.7%) experienced MCEs comprising cardiac death (n = 16), non-fatal myocardial infarction (n = 4), and unstable angina pectoris (n = 30). The multivariate Cox proportional hazards regression model analysis for the actual occurrence of MCEs showed the summed difference score % and MCE risks estimated with the CERS after treatment to be significant independent variables. Ischemic reduction after treatment contributed significantly to a decrease in the MCE risks. The MCE risks estimated with the CERS after treatment were generally consistent with the incidence of the MCEs actually observed.The CERS after treatment is a valuable formula for predicting prognosis in Japanese patients with coronary artery disease.

Topics: Contrast Media; Coronary Angiography; Coronary Artery Disease; Follow-Up Studies; Humans; Japan; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Predictive Value of Tests; Prognosis; Retrospective Studies; Risk Assessment; Sensitivity and Specificity; Tomography, Emission-Computed, Single-Photon

Direct ischemia imaging with F18-FDG can potentially overcome many limitations of SPECT-MPS inherent to "cold imaging". We compared SPECT-MPS with exercise F18-FDG PET in detection of ischemia in patients with suspected CAD.. 45 patients with clinical suspicion of CAD without the history of myocardial infarction were prospectively included. All patients underwent Tc-99m tetrofosmin SPECT-MPS and exercise F18-FDG PET imaging within 7 days of SPECT-MPS, and both modalities were compared with coronary angiography for detecting ischemia.. 27 patients had an abnormal coronary angiography (at least one coronary artery with stenosis >50%). Exercise F18-FDG performed better than SPECT-MPS in LAD and LCX territory with comparably good performance in RCA territory. Exercise F18-FDG performed better in single-vessel disease and equally good in multi-vessel disease compared to SPECT-MPS. Performance of exercise 18F-FDG study was significantly better than SPECT-MPS (P = .0014) in the analysis of the 81 vascular territories in the 27 patients with abnormal coronary angiography. Performance of exercise F18-FDG was significantly better than SPECT-MPS in detecting ischemia in suspected CAD patients.. Exercise F18-FDG imaging is a potentially useful ischemia imaging modality which offers the advantages of direct ischemia imaging in CAD patients.

Topics: Adult; Aged; Constriction, Pathologic; Coronary Angiography; Coronary Artery Disease; Female; Fluorodeoxyglucose F18; Humans; Image Processing, Computer-Assisted; Male; Middle Aged; Myocardial Infarction; Myocardial Ischemia; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Prospective Studies; Radionuclide Imaging; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon; Young Adult

Quantification of myocardial perfusion reserve (MPR) is an emerging topic in nuclear cardiology with an expected diagnostic and prognostic incremental value, especially for patients with severe coronary artery disease. The advent of new dedicated solid-state cameras has opened new perspectives for perfusion quantitation in SPECT. We appraised the feasibility of perfusion reserve estimation using a cadmium zinc telluride camera in a cohort of multivessel patients and its pertinence with respect to angiographic data.. Twenty-three patients with known multivessel coronary artery disease were prospectively enrolled. Dynamic SPECT acquisitions using (99m)Tc-tetrofosmin at rest and after vasodilator stress were performed using a dedicated cadmium zinc telluride camera. Reconstructed frames were automatically segmented to extract the vascular input function and the myocardial uptake curve. One-compartment kinetic modeling was used to estimate global and regional uptake values, and then myocardial blood flow was derived using the Renkin-Crone equation. Global and regional MPR was assessed using flow difference (stress - rest) and flow ratio (stress/rest). All patients underwent control coronary angiography within 4 wk, which served as the reference for MPR index assessment. Relevant angiographic findings included maximal stenosis and (for a subgroup of 26 vessels) invasive measurement of fractional flow reserve (FFR). A stenosis was considered obstructive if greater than 50% and an FFR abnormal if lower than 0.8.. Global MPR correlated well with number of obstructed vessels (P < 0.001). After multivariate analysis, both regional flow ratio and flow difference were significantly associated with maximal stenosis (P < 0.001) and FFR (P < 0.001). Regional MPR indices were significantly different in obstructed and nonobstructed vessels (P < 0.001) and in vessels with normal and abnormal FFR (P < 0.001). With a cutoff of 2, the sensitivity, specificity, and accuracy of regional flow ratio were, respectively, 80%, 85%, and 81% for the detection of obstructed vessels and 89%, 82%, and 85% for the detection of abnormal FFR.. Scintigraphic estimations of global and regional MPR in multivessel patients using a cadmium zinc telluride camera appear to correlate well with invasive angiographic findings, including maximal stenosis and FFR measurements.

Topics: Aged; Cohort Studies; Coronary Angiography; Coronary Artery Disease; Coronary Stenosis; Exercise Test; Feasibility Studies; Female; Fractional Flow Reserve, Myocardial; Heart; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Perfusion; Prospective Studies; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon

Prone imaging has been demonstrated to minimize diaphragmatic and breast tissue attenuation.. To determine the role of prone imaging on the reduction of unnecessary rest perfusion studies and coronary angiographies performed, thus decreasing investigation time and radiation exposure.. We examined 139 patients, 120 with an inferior wall and 19 with an anterior wall perfusion defect that might represented attenuation artifact. Post-stress images were acquired in both the supine and prone position. Coronary angiography was used as the "gold standard" for evaluating coronary artery patency. The study was terminated and rest imaging was obviated in the presence of complete improvement of the defect in the prone position. Quantitative interpretation was performed. Results were compared with clinical data and coronary angiographic findings.. Prone acquisition correctly revealed defect improvement in 89 patients (89/120) with inferior wall and 12 patients (12/19) with anterior wall attenuation artifact. Quantitative analysis demonstrated statistically significant difference in the mean summed stress scores (SSS) of supine and mean SSS of prone studies in patients with disappearing inferior wall defect in the prone position and patent right coronary artery (true negative results). The mean difference between SSS in supine and in prone position was higher with disappearing than with remaining defects.. Technetium-99m (Tc-99m) tetrofosmin myocardial perfusion imaging with the patient in the prone position overcomes soft tissue attenuation; moreover it provides an inexpensive, accurate approach to limit the number of unnecessary rest perfusion studies and coronary angiographies performed.

Topics: Aged; Artifacts; Coronary Angiography; Coronary Artery Disease; Exercise Test; Female; Humans; Male; Middle Aged; Myocardial Infarction; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Patient Positioning; Prone Position; Radiation Exposure; Radiopharmaceuticals; Risk Assessment; Sensitivity and Specificity; Statistics, Nonparametric; Time Factors; Tomography, Emission-Computed, Single-Photon

Attenuation correction using segmentation with scatter and photopeak window data (SSPAC) may enable evaluation of the attenuation map in a patient-specific manner without the need for additional radiation exposure and more acquisition time. We examined the feasibility of SSPAC and compared the sensitivity, specificity, and accuracy of this new correction method with that of conventional non-corrected myocardial perfusion single-photon emission computed tomography (SPECT) among patients with suspected or diagnosed coronary artery disease.. One hundred sixty-one patients who underwent both (99m)Tc-tetrofosmin stress/rest SPECT examination and invasive coronary angiography were enrolled in the study. Data from the SSPAC-corrected and non-corrected methods were analyzed quantitatively using summed stress scores. Attenuation maps were obtained successfully for 150 (93%) of the patients. The SSPAC-corrected and non-corrected methods accurately predicted coronary artery disease defined as >50% luminal stenosis verified by coronary artery angiography and/or prior myocardial infarction, for 91% and 77% patients, respectively (P < .05). For diagnosis of coronary artery disease, SSPAC improved sensitivity in the left anterior descending artery territory and specificity in the right coronary artery territory.. Attenuation correction with SSPAC may be a feasible method of correction for myocardial perfusion SPECT and in some cases may provide better accuracy for diagnosing coronary artery disease.

Topics: Aged; Body Mass Index; Coronary Angiography; Coronary Artery Disease; Coronary Vessels; Exercise Test; Female; Humans; Image Processing, Computer-Assisted; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Perfusion; Reproducibility of Results; Scattering, Radiation; Sensitivity and Specificity; Tomography, Emission-Computed, Single-Photon

We set out to develop normal databases and prospectively validate abnormality criteria for a low-dose Tc-99m tetrofosmin myocardial perfusion SPECT protocol using the 530c CZT camera.. All patients received 6 mCi rest/20 mCi stress doses of Tc-99m tetrofosmin. Rest and stress images were obtained over 7-9 and 5-7 minutes according to the chest size. Low-dose CT of the chest was obtained on a standalone CT scanner. Forty patients with very low likelihood (LLK) of coronary artery disease (CAD) were used to define the normal count distributions. The abnormality criteria were prospectively validated in 55 patients who had coronary angiography and in 40 patients with LLK of CAD.. The results for quantitative non-attenuation-corrected (AC) and AC analysis and visual analysis were as follows: sensitivity of 79%, 85%, and 92% (P = NS) and specificity of 44%, 75%, and 56% (P = NS), respectively. The normalcy rates for quantitative non-AC and AC analyses and visual analysis were 95%, 98%, and 98% (P = NS).. We have developed non-AC and AC normal databases for low-dose rest/stress Tc-99m tetrofosmin myocardial perfusion SPECT protocol using the 530c CZT camera. The per-patient diagnostic performance of quantitative analyses is not significantly different from visual analysis by an experienced reader.

Topics: Aged; Coronary Angiography; Coronary Artery Disease; Exercise Test; Female; Humans; Male; Middle Aged; Myocardial Ischemia; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Prospective Studies; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

Recently introduced ultrafast cardiac SPECT cameras with cadmium zinc telluride-based (CZT) detectors may provide superior image quality allowing faster acquisition with reduced radiation doses. Although the level of concordance between conventional SPECT and invasive fractional flow reserve (FFR) measurement has been studied, that between FFR and CZT-based SPECT is not yet known. Therefore, we aimed to assess the level of concordance between CZT SPECT and FFR in a large patient group with stable coronary artery disease.. Both invasive FFR and myocardial perfusion imaging with a CZT-based SPECT camera, using Tc-tetrofosmin as tracer, were performed in 100 patients with stable angina and intermediate grade stenosis on invasive coronary angiography. A cut-off value of <0.75 was used to define abnormal FFR.. The mean age of the patients was 64 ± 11 years, and 64 % were men. SPECT demonstrated ischaemia in 31 % of the patients, and 20 % had FFR <0.75. The concordance between CZT SPECT and FFR was 73 % on a per-patient basis and 79 % on a per-vessel basis. Discordant findings were more often seen in older patients and were mainly (19 %) the result of ischaemic SPECT findings in patients with FFR ≥ 0.75, whereas only 8 % had an abnormal FFR without ischaemia as demonstrated by CZT SPECT.. Only 20 - 30 % of patients with intermediate coronary stenoses had significant ischaemia as assessed by CZT SPECT or invasive FFR. CZT SPECT showed a modest degree of concordance with FFR, which is comparable with previous results with conventional SPECT. Further investigations are particularly necessary in patients with normal SPECT and abnormal FFR, especially to determine whether these patients should undergo revascularization.

Topics: Aged; Cadmium; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; Coronary Artery Disease; Female; Fractional Flow Reserve, Myocardial; Gamma Cameras; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Tellurium; Zinc

We have previously reported that 35% CO2 challenge induced myocardial ischemia in 81% of coronary artery disease (CAD) patients with comorbid panic disorder (PD) and previous positive nuclear exercise stress tests. However, it is yet unclear whether this is the case among CAD patients with PD and normal nuclear exercise stress test results. We hypothesized that a potent mental stressor such as a panic challenge among CAD patients with PD would also induce ischemia in patients with normal exercise stress tests.. Forty-one coronary artery disease patients with normal nuclear exercise stress tests (21 patients with PD and 20 without PD) were submitted to a well-established panic challenge test (with 1 vital capacity inhalation of a gas mixture containing 35% CO2 and 65% O2) and injected with Tc-99m-tetrofosmin (Myoview), upon inhalation. Single photon emission computed tomography imaging was used to assess per-panic challenge reversible myocardial ischemia and HR, BP, and a 12 lead ECG was continuously measured during the procedure.. Fifty-eight percent of panic disorder patients (12/21) had a panic attack during the panic challenge vs 15% (3/20) of controls (p=0.005). Only 10% of patients in each group displayed myocardial ischemia per panic challenge.. These findings suggest that panic attacks among panic disorder patients with lower-risk coronary artery disease may not confer a risk for myocardial ischemia.

Topics: Administration, Inhalation; Adult; Aged; Carbon Dioxide; Coronary Artery Disease; Exercise Test; Female; Humans; Male; Middle Aged; Myocardial Ischemia; Organophosphorus Compounds; Organotechnetium Compounds; Panic; Panic Disorder; Radiopharmaceuticals; Risk; Tomography, Emission-Computed, Single-Photon

Topics: Coronary Artery Disease; Female; Humans; Male; Organophosphorus Compounds; Organotechnetium Compounds; Tomography, Emission-Computed, Single-Photon

False-negative myocardial perfusion imaging (MPI) can by due to left main (LM) or three-vessel disease causing "balanced ischemia". However, so far prevalence of LM or three-vessel-disease in patients with normal MPI is unclear. We assessed prevalence, location, and extent of significant coronary artery disease (CAD) in patients with normal MPI.. Between 2006 and 2010, 256 patients with normal MPI who had invasive angiography because of persisting or worsening of the same initial symptoms were studied. Significant CAD was defined as stenosis > 70% or LM > 50%.. A total of 93 patients (36%) had significant CAD. Significant CAD was observed more frequently in males, higher age and those with typical angina complaints. Significant LM disease was present in 7%, three-vessel disease in 10%, two-vessel disease in 22%, and single vessel disease (not left main) in 61%. In those with single vessel disease, the location was the LAD in 40%, the RCA in 30%, and the LCX in 30%.. In selected patients with normal MPI, one-third had significant CAD. The majority of these patients had single vessel disease (not left main). LM or three vessel disease, causing "balanced ischemia", is a less common cause of false-negative MPI.

Topics: Age Distribution; Aged; Coronary Artery Disease; False Negative Reactions; Female; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Netherlands; Organophosphorus Compounds; Organotechnetium Compounds; Prevalence; Radiopharmaceuticals; Reproducibility of Results; Risk Assessment; Sensitivity and Specificity; Severity of Illness Index; Sex Distribution; Tomography, Emission-Computed, Single-Photon

Cardiogoniometry (CGM) is a novel resting electrocardiac method based on computer-generated three-dimensional data derived from cardiac potentials. The purpose of this study was to determine CGM's and electrocardiography's (ECG) accuracy for detecting myocardial ischemia and/or lesions in comparison with stress/rest myocardial perfusion scintigraphy (single photon emission computer tomography [SPECT]).. A cohort of consecutively enrolled patients (n = 100) with suspected or known coronary artery disease (mean age 67.8 years, 52% female) were examined by CGM and resting ECG before stress/rest myocardial scintigraphy.. Pathological scintigraphy findings at adenosine stress perfusion (ASP) and/or rest were conclusively identified in 21 patients. Diagnostic sensitivity was 71% for CGM and 24% for ECG, specificity was 70% for CGM and 95% for ECG. Reversible ischemia was diagnosed in 16 of 21 patients with pathological scintigraphy results. In this subgroup, sensitivity was 67% for CGM and 25% for ECG.. At rest, the sensitivity of a CGM significantly surmounts that of a standard 12-lead ECG for detection of isolated myocardial ischemia or myocardial lesions revealed by scintigraphy/SPECT; specificity is in a reasonable range. CGM's ease of use and its considerable agreement with the results of myocardial scintigraphy, suggests a possible role for patient screening in the primary care setting.

Topics: Aged; Coronary Artery Disease; Electrocardiography; Female; Humans; Male; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Rest; Sensitivity and Specificity; Tomography, Emission-Computed, Single-Photon; Vectorcardiography

To evaluate the relationships between measures of left ventricular (LV) filling dynamics at cadmium-zinc-telluride (CZT) imaging and indexes of LV diastolic function at transthoracic echocardiography.. Two hundred and forty-seven patients underwent myocardial perfusion imaging at rest and after stress with a low-dose CZT protocol and a baseline transthoracic echocardiography study. All patients were submitted to invasive or computed coronary angiography. The peak filling rate (PFR) and the time to PFR (TPFR) were derived from gated CZT images as measures of LV filling dynamics. LV diastolic function was also evaluated at echocardiography and the presence of significantly increased LV filling pressures determined. Increased LV filling pressures at transthoracic echocardiography were evident in 103 (42%) patients. Interestingly, independently from the presence of coronary artery disease, there was a strict correlation between the presence and severity of LV diastolic dysfunction at echocardiography and CZT-derived measures of filling dynamics, i.e., PFR (P = 0.001) and TPFR (P = 0.001). At receiving operating characteristic analysis, a composite index of reduced PFR (≤2.11 end-diastolic volume s(-1)) and increased TPFR (>234 ms) showed a sensitivity of 84% and a specificity of 67% in unmasking the presence of elevated LV filling pressures at echocardiography.. CZT-derived measures of LV filling dynamics correlate with echocardiographic parameters of diastolic function and may identify the presence of increased LV filling pressures.

Topics: Aged; Cadmium; Coronary Angiography; Coronary Artery Disease; Echocardiography, Doppler; Exercise Test; Female; Humans; Image Interpretation, Computer-Assisted; Male; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Tellurium; Ventricular Dysfunction, Left; Zinc

Early stress imaging (15 min after injection of the radiopharmaceutical) in 99mTc tetrofosmin myocardial perfusion scintigraphy (MPS) has been shown feasible in comparison to standard imaging after 45 minutes, but the effects on image quality and diagnostic accuracy ask for further evaluation.. 97 patients (61 men, 36 women, age 69 ± 11 years) underwent both early (EA) and standard (SA) acquisition (after 14 ± 4 min and 43 ± 6 min, respectively) using 99mTc tetrofosmin gated SPECT with iterative reconstruction. Sub-diaphragmatic tracer activity and image quality was scored in a 4-point scale by blinded observers. Semiquantitative myocardial perfusion analysis was performed on a 17-segment model using standard cardiac quantification SPECT software (4 DM-SPECT). Stenoses of indeterminate haemodynamic significance were validated by measurement of fractional flow reserve (FFR).. Extra-cardiac tracer activity was more commonly found in EA (43%) than in SA (38%), but without any diagnostic impact in > 95% of the patients. The mean summed stress score was significantly higher for early than standard imaging (6.4 ± 6.3 vs. 5.6 ± 6.1, p = 0.009). The amount of ischaemic area was not significantly different (EA: 9.1 ± 6.7 % vs. SA: 7.8 ± 6.9 %). The mean stress ejection fraction was 52 ± 11% (EA) compared to 55 ± 11 % (SA) (p = ns). FFR was inversely related to SDS at early (r = -0.704, p < 0.05) and standard (r = -0.678, p < 0.05) acquisition. All patients with a FFR < 0.8 (considered as hemodynamically significant stenoses) revealed a positive scan.. Stress 99mTc tetrofosmin MPS with early acquisition is feasible and at least equally accurate when iterative reconstruction is applied.

Topics: Aged; Cardiac-Gated Imaging Techniques; Coronary Artery Disease; Female; Fractional Flow Reserve, Myocardial; Germany; Humans; Image Enhancement; Image Interpretation, Computer-Assisted; Male; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Tomography, Emission-Computed, Single-Photon

Quantification of myocardial perfusion scintigraphy is often performed to assist physicians in detecting coronary artery disease (CAD). Modern software and hardware packages provide improvements able to shorten scan time and/or reduce administered activity, without compromising image quality in radionuclide myocardial perfusion imaging (MPI). Recently, multifocal collimators were introduced with dedicated reconstruction software, named IQ-SPECT, able to shorten considerably scan time. The aim of our study was to compare this new protocol to the already validated standard ones.. We enrolled 43 patients with suspected or diagnosed CAD. All patients underwent a two-days protocol radionuclide myocardial perfusion scan at rest and after a standard stress test (exercise or dipyridamole) after administering 99mTc-tetrofosmin. Images were acquired on a 2-head gamma camera and reconstructed with attenuation correction. All the images were scored using a 17-segments model by three experienced physicians, blind to clinical data and to acquisition and processing modality.. No significant differences were recorded in perfusion scores on paired t-test and Wilcoxon among the full-time images reconstructed with standard protocol or IQ-SPECT, both overall on a 17-segments evaluation and when considering different territories of distribution. MPI with IQ-SPECT protocol can be acquired at about a quarter scan time without disagreement compared to full time scan acquisition performed with standard protocols.

Topics: Adult; Aged; Algorithms; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; Coronary Artery Disease; Female; Humans; Image Interpretation, Computer-Assisted; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Pilot Projects; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity

For a 1-day myocardial perfusion SPECT (MPS) the recommendations for administered activity stated in the EANM guidelines results in an effective dose of up to 16 mSv per patient. Recently, a gamma camera system, based on cadmium zinc telluride (CZT) technology, was introduced. This technique has the potential to reduce the effective dose and scan time compared to the conventional NaI gamma camera. The aim of this study was to investigate if the effective dose can be reduced with a preserved image quality using CZT technology in MPS.. In total, 150 patients were included in the study. All underwent a 1-day (99m)Tc-tetrofosmin stress-rest protocol and were divided into three subgroups (n = 50 in each group) with 4, 3, and 2.5 MBq/kg body weight of administered activity in the stress examination, respectively. The acquisition time was increased in proportion to the decrease in administered activity. All examinations were analyzed for image quality by visual grading on a 4-point scale (1 = poor, 2 = adequate, 3 = good, 4 = excellent), by two expert readers.. The total effective dose (stress + rest) decreased from 9.3 to 5.8 mSv comparing 4 to 2.5 MBq/kg body weight. For the patients undergoing stress examination only (35%) the effective dose, administrating 2.5 MBq/kg, was 1.4 mSv. The image acquisition times for 2.5 MBq/kg body weight were 475 and 300 seconds (stress and rest) compared to 900 seconds for each when using conventional MPS. The average image quality was 3.7 ± 0.5, 3.8 ± 0.5, and 3.8 ± 0.4 for the stress images and 3.5 ± 0.6, 3.6 ± 0.6, and 3.5 ± 0.6 for the rest images and showed no statistically significant difference (P = .62) among the 4, 3, and 2.5 MBq/kg groups.. The new CZT technology can be used to considerably decrease the effective dose and acquisition time for MPS with preserved high image quality.

Topics: Aged; Body Weight; Cadmium; Coronary Artery Disease; Female; Gamma Cameras; Humans; Image Processing, Computer-Assisted; Likelihood Functions; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Perfusion; Radiation Dosage; Radiometry; Radiopharmaceuticals; Tellurium; Time Factors; Tomography, Emission-Computed, Single-Photon; Treatment Outcome; Zinc

There are no data regarding the long-term prognostic value of single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) in obese patients. The aim of this study was to examine the value of stress (99m)Tc-tetrofosmin MPI findings for the prediction of very long-term outcome in obese patients.. The study population consisted of 261 patients with a body mass index ≥30 kg/m(2) who underwent exercise or pharmacological stress (99m)Tc-tetrofosmin MPI for the assessment of known or suspected coronary artery disease. Endpoints during follow-up were all-cause mortality, cardiac death, nonfatal infarction, and coronary revascularization. Kaplan-Meier survival cures were constructed and univariate and multivariate analyses were performed to identify predictors of very long-term outcome.. The mean age was 59 ± 10 years, 42% of the patients was male, and the body mass index was on average 37 ± 7 kg/m(2). MPI findings were normal in 109 patients (42%). Myocardial perfusion abnormalities were fixed in 62 patients (24%) and reversible in 90 patients (34%). During a median 12-year follow-up, 91 (35%) patients died, and 27 (10%) had a nonfatal myocardial infarction. Survival curves were compared using the log-rank test at subsequent follow-up durations. Obese patients with a normal stress (99m)Tc-tetrofosmin study had a significantly better prognosis as compared with those with an abnormal study, up to 6 years after the test was performed.. Stress (99m)Tc-tetrofosmin MPI provides valuable prognostic information for the prediction of outcome in obese patients. Obese patients with a normal stress (99m)Tc-tetrofosmin study have a significantly better prognosis as compared with those with an abnormal study, up to 6 years after the test is performed.

Topics: Comorbidity; Coronary Artery Disease; Female; Humans; Incidence; Longitudinal Studies; Male; Middle Aged; Myocardial Perfusion Imaging; Netherlands; Obesity; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Radiopharmaceuticals; Reproducibility of Results; Risk Assessment; Sensitivity and Specificity; Survival Analysis; Survival Rate; Tomography, Emission-Computed, Single-Photon

Of various nuclear medicine techniques, F-18/flourodeoxyglucose (FDG) positron emission tomography (PET) is considered as the best modality for the assessment of viable myocardium (VM). In this study, we compared the diagnostic accuracy of nitrate augmented Tc-99m tetrofosmin gated G-single-photon emission computed tomography (SPECT) with FDG PET.. 54 consecutive cases of angiographically proven CAD with severe LV dysfunction were enrolled in the study. The patients underwent Tc-99m tetrofosmin G-SPECT and FDG PET as per the standard protocols and were compared.. SPECT data analysis indicated functional abnormalities in 661/918 myocardial segments. F-18 FDG PET revealed VM in 496/661 segments. The diagnostic accuracy of baseline NAC, postnitrate NAC, baseline AC, and postnitrate AC Tc-99m tetrofosmin SPECT was 84%, 87%, 90%, and 94%, respectively. κ values for NAC baseline, NAC postnitrate, AC baseline, and AC postnitrate Tc-99m tetrofosmin G-SPECT were 0.65, 0.70, 0.77, and 0.85, respectively. Attenuation correction revealed viability additionally in 46 segments which were non-viable on NAC postnitrate study (P < .001). Nitrate augmentation showed viability additionally in 25 segments which were non-viable on AC baseline scan (P = .004). On patient-based analysis FDG PET changes the management only in 13% (7/54) of patients.. Nitrate augmented AC Tc-99m tetrofosmin G-SPECT shows excellent (κ = .85) agreement with FDG PET. FDG PET changes management only in 13% of the patients. Tc-99m tetrofosmin G-SPECT being more widely available and cheaper imaging modality can be reliably used to detect VM where FDG PET is not available.

Topics: Adult; Aged; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; Coronary Artery Disease; Female; Fluorodeoxyglucose F18; Heart; Humans; Male; Middle Aged; Myocardial Infarction; Nitrates; Organophosphorus Compounds; Organotechnetium Compounds; Positron-Emission Tomography; Predictive Value of Tests; Prospective Studies; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Ventricular Dysfunction, Left

Exercise (99m)Tc-tetrofosmin single-photon emission computed tomography (SPECT) is a useful tool for short- and medium-term risk stratifications. Currently, the long-term prognostic application of this technique has not been evaluated.. Exercise (99m)Tc-tetrofosmin was performed in 655 consecutive patients. Ten patients who underwent revascularization <60 days after nuclear testing were excluded from the analysis. The present data are based on 638 patients with complete follow-up. An abnormal SPECT study was defined as the presence of fixed and/or reversible perfusion defects. End points were cardiac death, nonfatal infarction, and late coronary revascularization. A total of 344 (54%) patients had an abnormal SPECT study. Perfusion defects included fixed defects alone in 186 patients (29%) and reversible defects in 158 (25%) patients. During a mean follow-up of 11.0 ± 3.3 years, 174 (27%) patients died (all-cause mortality). Nonfatal myocardial infarction occurred in 76 (12%) patients, and late coronary revascularization was performed in 194 (30%) patients. Univariable and multivariable Cox proportional hazard regression analyses showed that exercise (99m)Tc-tetrofosmin SPECT provided prognostic information incremental to clinical data and exercise test data. Patients with a normal SPECT had a relatively favorable long-term prognosis, in contrast to patients with an abnormal study who had a significantly increased risk of cardiac events. The SPECT parameters abnormal scan, reversible defect, and summed rest score were strong predictors of long-term outcome.. Exercise (99m)Tc-tetrofosmin myocardial perfusion SPECT has an incremental long-term prognostic value over clinical and stress test parameters for the prediction of major adverse cardiac events.

Topics: Adult; Aged; Coronary Artery Disease; Exercise Test; Female; Humans; Kaplan-Meier Estimate; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon

Topics: Coronary Artery Disease; Exercise Test; Female; Humans; Male; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon

Commercial normal stress databases in myocardial perfusion scintigraphy (MPS) commonly consist of 30-40 individuals. The aim of the study was to determine how many subjects are needed.. Four normal stress databases were developed using patients who underwent 99mTc MPS: non-corrected images (NC) for male, NC for female, attenuation-corrected images (AC) for male and AC for female subjects. 126 male and 205 female subjects were included. The normal database was created by alternatingly computing the mean of all normal subjects and normalizing the subjects with respect to this mean, until convergence. Coefficients of variation (CV) were created for increasing number of included patients in the four different normal stress databases.. Normal stress databases with < 35 subjects had a high CV. Mean CV -2 standard deviations (SD) decreased with 28% between two and five included subjects, 71% between two and 35 subjects and 83% between two and 100 included subjects for NC man.. We conclude that the commonly used 30-40 individuals for making a normal stress database might not be enough due to the high CV. We propose that normal stress databases should consist of more than 30-40 individuals, preferably more than 50 individuals, both for NC and AC studies.

Topics: Adenosine; Adult; Aged; Aged, 80 and over; Coronary Artery Disease; Coronary Circulation; Databases, Factual; Exercise Test; Female; Heart Ventricles; Humans; Image Processing, Computer-Assisted; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Predictive Value of Tests; Radiopharmaceuticals; Reference Values; Sample Size; Tomography, Emission-Computed, Single-Photon; Vasodilator Agents

The purpose of this study is to evaluate the feasibility, the image quality, and the clinical relevance of an early gated post-stress (GPS) single-photon emission computed tomography (SPECT) tetrofosmin (Myoview™-GE Healthcare) acquisition protocol. Time delay between myocardial technetium-labeled tracer administration and SPECT acquisition is usually about 30 minutes after stress, and 45 to 60 minutes at rest: because of the absence of significant redistribution, perfusion images are related to stress even 30 minutes after stress injection, while function and thickening data obtained with gated acquisition 30 minutes after stress are mainly related to rest conditions.. 194 patients were prospectively included and analyzed, in a multicenter registry. Three gated-SPECT 99(m)Tc-Tetrofosmin studies were performed per patient: GPS-SPECT, 30 minutes post-stress (GS30), and at rest (GR30).. GPS image quality was excellent/good (93.9%), and similar to GS30 images (96.6%). The presence of adjacent myocardial sub-diaphragmatic activity on GPS images was similar to GS30 images (24% vs 22%), and less frequent than on GR30 images (31%). For perfusion, thickening, and motion scores, there was no significant difference between early and 30 minute post-stress in the global patient population, but significant differences were observed between GPS and GS30 for LVEF (65% ± 15% vs 63% ± 14%). In the ischemic patients, with the stress-rest protocol, the perfusion score was 14.2 on GPS images and 12.4 on GS30 images (P = .002).. Tetrofosmin early GPS-SPECT is feasible without impairment of image quality (better count rate). Ischemic defect size on early post-stress images is slightly more pronounced than at 30 minutes: this could modify therapeutic decision. This technique produces reliable function information during early post-stress period, and might be useful for disclosing transient motion abnormalities.

Topics: Cardiac-Gated Imaging Techniques; Coronary Artery Disease; Exercise Test; Feasibility Studies; Female; France; Humans; Image Enhancement; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Ventricular Dysfunction, Left

Aims Although cardiac hybrid imaging, fusing single-photon emission computed tomography (SPECT) myocardial perfusion imaging with coronary computed tomography angiography (CCTA), provides important complementary diagnostic information for coronary artery disease (CAD) assessment, no prognostic data exist on the predictive value of cardiac hybrid imaging. Hence, the aim of this study was to assess the prognostic value of hybrid SPECT/CCTA images. Methods and results Of 335 consecutive patients undergoing a 1-day stress/rest (99m)Tc-tetrofosmin SPECT and a CCTA, acquired on stand-alone scanners and fused to obtain cardiac hybrid images, follow-up was obtained in 324 patients (97%). Survival free of all-cause death or non-fatal myocardial infarction (MI) and free of major adverse cardiac events (MACE: death, MI, unstable angina requiring hospitalization, coronary revascularizations) was determined using the Kaplan-Meier method for the following groups: (i) stenosis by CCTA and matching reversible SPECT defect; (ii) unmatched CCTA and SPECT finding; and (iii) normal finding by CCTA and SPECT. Cox's proportional hazard regression was used to identify independent predictors for cardiac events. At a median follow-up of 2.8 years (25th-75th percentile: 1.9-3.6), 69 MACE occurred in 47 patients, including 20 death/MI. A corresponding matched hybrid image finding was associated with a significantly higher death/MI incidence (P < 0.005) and proved to be an independent predictor for MACE. The annual death/MI rate was 6.0, 2.8, and 1.3% for patients with matched, unmatched, and normal findings. Conclusion Cardiac hybrid imaging allows risk stratification in patients with known or suspected CAD. A matched defect on hybrid image is a strong predictor of MACE.

Topics: Aged; Angina, Unstable; Cause of Death; Coronary Angiography; Coronary Artery Disease; Death, Sudden, Cardiac; Female; Hospitalization; Humans; Kaplan-Meier Estimate; Male; Middle Aged; Myocardial Infarction; Myocardial Revascularization; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Radiation Dosage; Radiopharmaceuticals; Risk Factors; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

Cardiac hybrid imaging by fusing single-photon emission computed tomography (SPECT) myocardial perfusion imaging with coronary computed tomography angiography (CCTA) provides important complementary diagnostic information for coronary artery disease (CAD) assessment. We aimed at assessing the impact of cardiac hybrid imaging on the choice of treatment strategy selection for CAD.. Three hundred and eighteen consecutive patients underwent a 1 day stress/rest (99m)Tc-tetrofosmin SPECT and a CCTA on a separate scanner for evaluation of CAD. Patients were divided into one of the following three groups according to findings in the hybrid images obtained by fusing SPECT and CCTA: (i) matched finding of stenosis by CCTA and corresponding reversible SPECT defect; (ii) unmatched CCTA and SPECT finding; (iii) normal finding by both CCTA and SPECT. Follow-up was confined to the first 60 days after hybrid imaging as this allows best to assess treatment strategy decisions including the revascularization procedure triggered by its findings. Hybrid images revealed matched, unmatched, and normal findings in 51, 74, and 193 patients. The revascularization rate within 60 days was 41, 11, and 0% for matched, unmatched, and normal findings, respectively (P< 0.001 for all inter-group comparisons).. Cardiac hybrid imaging with SPECT and CCTA provides an added clinical value for decision making with regard to treatment strategy for CAD.

Topics: Aged; Coronary Artery Disease; Coronary Stenosis; Feasibility Studies; Female; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Myocardial Revascularization; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

The American Society of Nuclear Cardiology and the Society of Nuclear Medicine state that incorporation of attenuation-corrected (AC) images in myocardial perfusion scintigraphy (MPS) will improve image quality, interpretive certainty, and diagnostic accuracy. However, commonly used software packages for MPS usually include normal stress databases for non-attenuation corrected (NC) images but not for attenuation-corrected (AC) images. The aim of the study was to develop and compare different normal stress databases for MPS in relation to NC vs. AC images, male vs. female gender, and presence vs. absence of obesity. The principal hypothesis was that differences in mean count values between men and women would be smaller with AC than NC images, thereby allowing for construction and use of gender-independent AC stress database.. Normal stress perfusion databases were developed with data from 126 male and 205 female patients with normal MPS. The following comparisons were performed for all patients and separately for normal weight vs. obese patients: men vs. women for AC; men vs. women for NC; AC vs. NC for men; and AC vs. NC for women.. When comparing AC for men vs. women, only minor differences in mean count values were observed, and there were no differences for normal weight vs. obese patients. For all other analyses major differences were found, particularly for the inferior wall.. The results support the hypothesis that it is possible to use not only gender independent but also weight independent AC stress databases.

Topics: Adult; Aged; Aged, 80 and over; Body Weight; Coronary Artery Disease; Databases, Factual; Exercise Test; Female; Humans; Image Interpretation, Computer-Assisted; Male; Middle Aged; Obesity; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reference Values; Reproducibility of Results; Sex Factors; Software; Tomography, Emission-Computed, Single-Photon

The location of a myocardial lesion on a wall thickening polar map often does not coincide with the location of the lesion on a perfusion polar map, especially when the myocardial lesion is located at the mid cardiac region. The purpose of this study was to determine the frequency and extent of discrepancy in the location of the lesion between perfusion and wall thickening polar maps on gated single photon emission computed tomography (SPECT) using lesion axis angle (LAA).. One hundred and forty-seven consecutive patients (male : female = 80 : 67, age range: 41-96 years) who underwent myocardial gated (99m)Tc-tetrofosmin SPECT on the suspicion of myocardial ischemia or infarct between September 2003 and September 2008 and showed both reduced myocardial perfusion and wall thickening on gated SPECT at mid cardiac region were reviewed. LAA, which is the angle between the lesion axis on perfusion and wall thickening polar maps, was measured for the patients who showed a discrepancy in lesion axis between the two polar maps. LAA was said to have a positive value when the lesion axis of the wall thickening polar map showed a counterclockwise angular rotation as compared with that of a perfusion polar map. The patients with LAA of less than 10 degrees were considered as having no lesion axis discrepancy between perfusion and wall thickening polar maps. LAA was correlated with left ventricular ejection fraction (LVEF) on gated SPECT using Pearson's correlation. Furthermore, two groups, one with LAA of >or=10 degrees and the other with LAA less than 10 degrees were correlated with dichotomous groups with >or=50% and less than 50% LVEF, using the chi(2) test. Then, 35 patients with acute coronary syndrome (ACS group) were analyzed separately for correlation between LAA and LVEF.. The mean +/- SD of LAA was 44.31+/-30.77 degrees (range: 0-145 degrees ). LAA was 0-10 degrees in 25 patients, 11-30 degrees in 24 patients, 31-60 degrees in 58 patients, 61-90 degrees in 30 patients, and >90 degrees in 10 patients. In addition, the lesion axis of the wall thickening polar map as compared with that of the perfusion polar map was rotated in the counterclockwise direction in 122 patients and not rotated in 25 patients. LVEF on gated SPECT showed positive correlation with LAA (P = 0.000147). In addition, there was statistically significant correlation (P = 0.001) when the two groups with LAA of >or=10 degrees and less than 10 degrees , respectively, were correlated with the groups of >or=50% and less than 50% LVEF. For the ACS group, the mean +/- SD of LAA was 45.88+/-30.30 degrees (range: 0-135 degrees ) and LVEF showed positive correlation with LAA (P = 0.0001). There was no significant statistical difference concerning LAA and LVEF between ACS group and non-ACS group (P = 0.725 and P = 0.473, respectively).. In most of our patients with coronary artery disease, the lesion axis of reduced wall thickening was rotated in the counterclockwise direction as compared with that of reduced perfusion on SPECT polar maps, especially when the myocardial lesion was at mid cardiac region. The LAA decreased as the LVEF decreased. This might be related to spatiotemporal distortion of myocardial contraction mentioned in the helical heart concept.

Topics: Adult; Aged; Aged, 80 and over; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; Coronary Artery Disease; Coronary Circulation; Electrocardiography; Female; Heart; Humans; Male; Middle Aged; Movement; Myocardium; Organophosphorus Compounds; Organotechnetium Compounds; Rotation

We aimed at establishing the optimal scan time for nuclear myocardial perfusion imaging (MPI) on an ultrafast cardiac gamma-camera using a novel cadmium-zinc-telluride (CZT) solid-state detector technology.. Twenty patients (17 male; BMI range, 21.7-35.5 kg/m(2)) underwent 1-d (99m)Tc-tetrofosmin adenosine stress and rest MPI protocols, each with a 15-min acquisition on a standard dual-detector SPECT camera. All scans were immediately repeated on an ultrafast CZT camera over a 6-min acquisition time and reconstructed from list-mode raw data to obtain scan durations of 1 min, 2 min, etc., up to a maximum of 6 min. For each of the scan durations, the segmental tracer uptake value (percentage of maximum myocardial uptake) from the CZT camera was compared by intraclass correlation with standard SPECT camera data using a 20-segment model, and clinical agreement was assessed per coronary territory. Scan durations above which no further relevant improvement in uptake correlation was found were defined as minimal required scan times, for which Bland-Altman limits of agreement were calculated.. Minimal required scan times were 3 min for low dose (r = 0.81; P < 0.001; Bland-Altman, -11.4% to 12.2%) and 2 min for high dose (r = 0.80; P < 0.001; Bland-Altman, -7.6% to 12.9%), yielding a clinical agreement of 95% and 97%, respectively.. We have established the minimal scan time for a CZT solid-state detector system, which allows 1-d stress/rest MPI with a substantially reduced acquisition time resulting in excellent agreement with regard to uptake and clinical findings, compared with MPI from a standard dual-head SPECT gamma-camera.

Topics: Adult; Aged; Aged, 80 and over; Cadmium; Coronary Artery Disease; Coronary Circulation; Dose-Response Relationship, Drug; Female; Gamma Cameras; Heart; Humans; Image Processing, Computer-Assisted; Linear Models; Male; Microcomputers; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Perfusion; Phantoms, Imaging; Radiopharmaceuticals; Tellurium; Tomography, Emission-Computed, Single-Photon; Zinc

We previously demonstrated that early (15', T1) post-stress myocardial imaging with Tetrofosmin could be more accurate than standard acquisitions (45', T2) in identifying coronary artery disease.. To clarify this phenomenon, 120 subjects (age 61 +/- 10 years) with both T1 and T2 scans were divided into Group 1 (53/120 pts) with more ischemia at T1 vs T2 imaging (T1-T2SDS > or = 3); Group 2 (67/120 pts) with similar results (T1-T2SDS < or = 2). Myocardial areas were categorized as control nonischemic, ischemic, and scarred on the basis of perfusion/contraction properties and coronary anatomy. In each area, regional myocardial count statistic and semiquantitative wall motion/thickening values were obtained. Analysis of T1 and T2 post-stress myocardial counts demonstrated a significant Tetrofosmin wash-out rate that was higher in Group 1 control nonischemic regions (15 +/- 8% vs 13.6 +/- 9.6%, P < .02), significantly lower in Group 1 ischemic regions (7 +/- 10% vs 12.2 +/- 9.5%, P < .0001), and comparable between scarred areas of the two groups (P = NS). Delta post-stress wall thickening (T1-T2) was lower in Group 1 ischemic regions (-4.5 +/- 9.15% vs -1.90 +/- 7.0%, P < .001) and comparable in both control nonischemic and scarred areas of the two groups (P = NS).. The clinical result of Tetrofosmin gated-SPECT can be influenced by the post-stress acquisition time because of ischemic-induced regional wall thickening abnormalities and the existence of a differential radiotracer myocardial wash-out.

Topics: Adult; Aged; Aged, 80 and over; Coronary Angiography; Coronary Artery Disease; Female; Heart; Humans; Male; Middle Aged; Motion; Myocardium; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon

Elevated transient ischemic dilatation (TID) ratio during myocardial perfusion imaging (MPI) is described as a marker of severe CAD, even in acquisitions with normal perfusion. This was initiated to explore the effects of stressor type on the TID. Additionally the relation between the TID and other functional parameters, such as end diastolic volume (EDV), end systolic volume (ESV), and left ventricle ejection fraction (LVEF), heart rate (HR), and severity of ischemia, was evaluated.. A total of 299 consecutive patients referred for a 2-day stress/rest MPI protocol were included. Patients were stressed with either adenosine (n = 164) or exercise (n = 135). MPI data were analyzed with an automated software tool to determine TID, EDV, ESV, LVEF, SSS, and SDS. The SDS was used to quantify the degree of ischemia, with a SDS > or = 3 considered ischemic.. Comparison of the adenosine and exercise stressed population revealed significant differences, especially in parameters derived from the poststress acquisition. Within the exercise stressed population, TID was proportional with the SDS (R(2) = .12); whereas the adenosine population did not show such a relation (R(2) = .001). Difference in HR between rest and poststress acquisitions showed high levels of linear regression with TID values of both the adenosine (R(2) = .41) and exercise (R(2) = .29) stressed population.. In an exercise stressed population, TID is determined by both the degree of ischemia and the heart-rate difference between the two acquisition moments. TID within the adenosine population was found to be highly proportional with the HR, rather than with the degree of ischemia.

Topics: Adenosine; Aged; Automation; Coronary Artery Disease; Exercise; Female; Heart; Heart Rate; Humans; Male; Middle Aged; Myocardial Ischemia; Organophosphorus Compounds; Organotechnetium Compounds; Perfusion; Radionuclide Imaging; Retrospective Studies; Ventricular Function, Left

We investigated whether myocardial perfusion imaging (MPI) can demonstrate the effect of classical preconditioning.. 21 patients with documented coronary artery disease (stenosis>or=70%) underwent two exercise stress tests (EST) with concomitant MPI, using TL-201 for the first and tetrofosmin-Tc-99m for the second. A third MPI was performed at rest, using Tc-99m. Total defect score was derived by summing tracer uptake in a 17 segments left ventricle model, graded on a 5-point scale. Tomographic images were also analyzed quantitatively, to derive the total defect size.. Maximum ST depression did not differ significantly between the two EST (2.2+/-1 vs 2.2+/-1 mm, p=NS), however in the second EST longer times for onset of ischemic changes (228+/-94 vs 265+/-103 s, p=0.01) and appearance of angina (282+/-153 vs 328+/-177 s, p=0.04) were observed. Exercise perfusion abnormalities were significantly lower in the second MPI, in terms of both total defect score (19.2+/-11.5 vs 10+/-10.4, p<0.0001) and total defect size (28.3+/-16.9 vs 13.8+/-15.8, p<0.0001).. Significant improvement in perfusion pattern was demonstrated in the second MPI, accompanied by delayed appearance of ischemic manifestations. The improvement in myocardial perfusion extends far beyond the changes that can be attributed to differences in myocardial uptake between tracers, reflecting the effect of classical preconditioning.

Topics: Aged; Coronary Artery Disease; Exercise Test; Female; Heart Ventricles; Humans; Ischemia; Ischemic Preconditioning; Male; Middle Aged; Myocardial Ischemia; Organophosphorus Compounds; Organotechnetium Compounds; Perfusion; Time Factors

Topics: Aged, 80 and over; Coronary Artery Disease; Coronary Vessels; Heart; Humans; Male; Organophosphorus Compounds; Organotechnetium Compounds; Tomography, Emission-Computed, Single-Photon

To determine diagnostic accuracy, effective radiation dose, and potential value of computed tomography coronary angiography (CTCA) for hybrid imaging with single-photon emission computed tomography (SPECT) comparing prospective electrocardiogram (ECG)-triggering vs. retrospective ECG-gating.. Two hundred patients underwent standard myocardial stress/rest- SPECT perfusion imaging, which served as standard of reference. One hundred consecutive patients underwent 64-slice CTCA using prospective ECG-gating, and were compared with 100 patients who had previously undergone CTCA using retrospective ECG-gating. For predicting ischaemia, CTCA with prospective ECG-triggering and a stenosis cut-off >50% had a per-vessel sensitivity, specificity, negative, and positive predictive value of 100, 84, 100, and 30%; respective values for CTCA with retrospective ECG-gating were similar (P = n.s.): 86, 83, 98, and 33%. Combining CTCA with stress-only SPECT revealed 100% clinical agreement with regard to perfusion defects, and provided additional information in half the patients on preclinical coronary findings. Effective radiation dose was 2.2 +/- 0.7 mSv for CTCA with prospective ECG-triggering, and 19.7 +/- 4.2 mSv with retrospective ECG-gating (P < 0.001) (5.4 +/- 0.8 vs. 24.1 +/- 4.3 mSv for hybrid imaging).. Prospective ECG-triggering for CTCA reduces radiation dose by almost 90% without affecting diagnostic performance. Combined imaging with stress-only SPECT is an attractive alternative to standard stress/rest-SPECT for evaluation of coronary artery disease, offering additional information on preclinical atherosclerosis.

Topics: Adult; Aged; Aged, 80 and over; Coronary Angiography; Coronary Artery Disease; Electrocardiography; Female; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Prospective Studies; Radiation Dosage; Radiopharmaceuticals; Retrospective Studies; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

Estimation of the left ventricular ejection fraction (LVEF) using myocardial perfusion imaging is increasingly used in the evaluation of coronary artery disease. This study aims to compare the effect of (i) two commercially available software packages: quantitative gated single-photon emission computed tomography (SPECT) (QGS) and 4DM-SPECT, and (ii) prereconstruction filtering, on LVEF quantification.. Images from 101 patients were reconstructed using AutoCardiac and processed using QGS and 4DM-SPECT. Filtering was performed before reconstruction using Hermes FBP SPET on a group of 32 consecutive patients using Butterworth filters (orders 5 and 10; cut-off frequency 0.5-1.2 cycles/cm).. Good correlation was observed between QGS and 4DM-SPECT (r=0.88), with an average difference of 2.1%. The difference in LVEF between the two packages ranged from 21 to -28%. The LVEF was overestimated at cut-off frequencies < or = 0.8 cycles/cm compared with higher cut-off frequencies in 26 of 30 (87%) patients.. There was a clinically significant difference between the LVEF calculated by QGS and 4DM-SPECT and consequently the two packages should not be used interchangeably. The effect of cut-off frequency on LVEF estimation was found to be very patient specific. Changing the cut-off frequency by as little as 0.1 cycles/cm can cause clinically significant differences in LVEF estimation.

Topics: Adult; Aged; Aged, 80 and over; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; Coronary Artery Disease; Female; Humans; Image Processing, Computer-Assisted; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Software; Stroke Volume

We evaluated the determinants of vessel contrast in prospectively ECG-triggered CT coronary angiography (CTCA). Seventy patients underwent low-dose CTCA using body mass index (BMI)-adapted tube parameters and a fixed contrast material bolus. Contrast to noise ratio (CNR) was calculated from contrast (between coronaries and perivascular tissue) and image noise (standard deviation of aortic attenuation). Cardiac output (CO) was calculated from gated (99m)Tc-tetrofosmin-SPECT. Mean radiation dose was 2.13 +/- 0.69 mSv. Image noise was not affected by BMI (r = 0.1, P = 0.36), while CNR was inversely related to body surface area (BSA) (r = -0.5, P < 0.001) and CO (r = -0.45, P < 0.001). After successfully overcoming the impact of BMI on image noise by adapting tube parameters, CNR mainly depends on coronary vessel contrast. The latter reflects the dilution of the contrast material by blood volume and CO, which are both correlated to BSA. Therefore, BSA adapted contrast administration may help to compensate for this effect.

Topics: Artifacts; Blood Volume; Body Mass Index; Body Surface Area; Cardiac Output; Contrast Media; Coronary Angiography; Coronary Artery Disease; Electrocardiography; Humans; Organophosphorus Compounds; Organotechnetium Compounds; Predictive Value of Tests; Prospective Studies; Radiation Dosage; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed; Triiodobenzoic Acids

Topics: Coronary Artery Disease; Coronary Occlusion; Diabetes Complications; Fistula; Heart Diseases; Heart Ventricles; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon

Renal function is known to be a strong predictor of cardiovascular prognosis, and cardiorenal disease is increasingly investigated in medical research. In this study, we tested the hypothesis that a single combined cardiorenal scintigraphy examination with the perfusion tracer (99m)Tc-tetrofosmin is feasible and may allow the simultaneous investigation of cardiac and renal pathology in cardiovascular patients.. Thirty patients scheduled for dual-day gated SPECT also gave their informed consent for a renal acquisition after a single injection of 370 MBq of (99m)Tc-tetrofosmin, at rest (30 patients) or with adenosine (21 patients), and to undergo an additional standard renal study with the glomerular tracer (99m)Tc-diethylenetriaminepentaacetic acid (DTPA) (74 MBq) after 1 wk (24 patients). Kidney images and renograms were obtained. Renal uptake index, expressed as the percentage ratio of kidney counts cumulated over the second minute after injection to the administered dose, was calculated as a functional renal parameter. Time to peak activity and separate kidney percentage uptake (as the percentage contribution of each kidney to total renal uptake) were also calculated.. Compared with (99m)Tc-DTPA, (99m)Tc-tetrofosmin provided better-quality kidney images, with a higher uptake index (13.17% +/- 4.76% vs. 8.33% +/- 2.45%, P < 0.001) and with comparable separate kidney percentage uptake and times to peak activity. (99m)Tc-tetrofosmin uptake index was significantly lower in the patients who were more compromised according to renal and cardiovascular functional parameters, and correlated with (99m)Tc-DTPA uptake index (r = 0.77, P < 0.001), serum creatinine (r = 0.59, P < 0.005), log brain natriuretic peptide N-terminal levels (r = -0.65, P < 0.005), myocardial and carotid intima-media wall thickness (for both, r = -0.61, P < 0.005), and the Doppler index of renal vascular resistance (r = -0.60, P < 0.005). In the 21 patients who underwent the provocative test, adenosine induced a significant decrease in renal (99m)Tc-tetrofosmin uptake index (from 14.12% +/- 4.50% to 11.81% +/- 3.33%, P < 0.005) suggesting a decrement in renal perfusion or function.. (99m)Tc-tetrofosmin cardiorenal scintigraphy is feasible at low cost as a single-shot study and may allow both the evaluation of renal morphology and renograms during a cardiac study and the calculation of renal functional parameters.

Topics: Adenosine; Adult; Aged; Aged, 80 and over; Algorithms; Coronary Artery Disease; Female; Humans; Image Enhancement; Image Interpretation, Computer-Assisted; Infusions, Intravenous; Kidney Diseases; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radioisotope Renography; Radiopharmaceuticals; Reproducibility of Results; Rest; Sensitivity and Specificity; Vasodilator Agents

99mTc-tetrofosmin single photon emission computed tomography (SPECT) is routinely used in the evaluation of coronary artery disease. A variety of different tumors, however, also demonstrate 99mTc-tetrofosmin uptake. We report six patients found with unexpected mediastinal and thoracic tumor uptake during Tc-tetrofosmin myocardial perfusion scintigraphy (MPS).. We investigated 2,155 patients with Tc-tetrofosmin MPS during 2006-2007. One thousand four hundred and eighty-six of these patients had no coronary history and were sent to our department due to newly developed thoracic complaint such as chest pain, dyspnea and others. Six hundred and sixty-nine patients had coronary history. All patients underwent 99mTc-tetrofosmin exercise study. Patients with unexpected extracardiac Tc-tetrofosmin findings during MPS were referred to PET/CT for further diagnostic investigation. Region of interest (ROI; 99mTc-tetrofosmin) and SUVmax (2-[F]fluoro-2-deoxy-D-glucose, F-FDG) were estimated and the results were compared with histological findings.. Abnormal mediastinal and/or thoracic activities were visualized in six of the 2,155 patients with 99mTc-tetrofosmin images. Subsequently, the patients underwent resection of a thymoma (n=2), nonsmall cell lung cancer (n=1) and breast cancer (n=3). In the patients with breast cancer one was a male patient with ductal, invasive breast cancer. Benign thymomas showed high 99mTc-tetrofosmin ROI >4.0 and low F-FDG SUVmax <2.0, whereas low 99mTc-tetrofosmin ROI <2.0 were found in nonsmall cell lung cancer and breast cancer and high F-FDG SUVmax >2.5 in these malignant tumors.. During Tc-tetrofosmin SPECT exercise stress tests performed in patients with suspected coronary artery disease, much more attention must be given to unexpected extracardiac uptakes. With 99mTc-tetrofosmin a large variety of different unknown tumors can be detected during MPS.

Topics: Aged; Breast Neoplasms, Male; Carcinoma, Non-Small-Cell Lung; Coronary Artery Disease; Female; Fluorodeoxyglucose F18; Heart; Humans; Lung Neoplasms; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Positron-Emission Tomography; Radiography; Radiopharmaceuticals; Thymoma; Thymus Neoplasms; Tomography, Emission-Computed; Tomography, Emission-Computed, Single-Photon

To evaluate the long-term prognostic value of Tc-99m tetrofosmin myocardial gated-SPECT in asymptomatic patients after coronary artery stenting.. We included 246 consecutive patients in the study. All patients underwent exercise gated-single photon emission computed tomography (SPECT) myocardial imaging 5 to 7 months after percutaneous coronary intervention (PCI) and were followed for a mean period of 8.3 years (SD = 2.9). Myocardial scintigrams were evaluated calculating the summed stress score (SSS), summed rest score, and summed difference score (SDS) indexes. Cardiovascular death and nonfatal myocardial infarction were considered hard cardiac events, whereas late revascularization (>3 months after myocardial SPECT) procedures were considered to be soft events. Cox proportional hazard models were applied to evaluate the association between several variables and the investigated outcome.. During the follow-up period, hard cardiac events occurred in 32 (13%) patients (cardiac death occurred in 12 patients and nonfatal myocardial infarction in 20 patients). In addition, 60 (24.4%) patients underwent a late revascularization procedure. When multiple Cox regression analysis was implied, the factors that remained significant in the final model for soft events were SSS, SDS, and angina during exercise testing. In addition, SSS, SDS, and left ventricular dilatation were independently associated with hard cardiac events as defined from the results of multiple analysis. However, SSS and SDS were the only independent predictors for both hard and soft events.. Tc-99m tetrofosmin myocardial perfusion imaging (MPI), performed 6 months post-percutaneous coronary intervention, has an independent and powerful clinical value to predict hard and soft cardiac events in asymptomatic patients after PCI.

Topics: Angioplasty, Balloon, Coronary; Coronary Artery Disease; Coronary Circulation; Coronary Restenosis; Coronary Vessels; Exercise Test; Female; Gated Blood-Pool Imaging; Heart; Humans; Male; Middle Aged; Myocardial Infarction; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon

The prognostic value of ECG-gated rest 201Tl/stress 99mTc-tetrofosmin myocardial perfusion single-photon emission computed tomography for the prediction of acute coronary syndrome (ACS: myocardial infarction (MI) and unstable angina (UA)) and the implications of ejection fraction (EF) has not yet been defined in Japanese.. The 1,895 patients were followed up for the occurrence ACS. The mean follow-up interval was 26.9+/-15.5 months. The 142 patients with revascularization within 60 days were censored. Summed stress score (SSS) and summed difference score (SDS) were calculated. The 19 MI and 29 UA occurred (1.1% and 1.6%, respectively). Univariate Cox analysis showed that hypertension (Wald 5.09, p<0.05), poststress EF (Wald 10.9, p<0.01), SSS (Wald 12.4, p<0.001) and SDS (Wald 18.7, p<0.001) were significant predictors of ACS. Multivariate Cox analysis showed that hypertension (Wald 4.27, p<0.05) and SDS (Wald 8.59, p<0.01) were independent predictors. When multiple clinical risk factors (number of coronary risk factors > or =2), significant ischemia (SDS > or =4) and low EF (EF <45%) were applied to multivariate Cox analysis, the combination of significant ischemia and low EF showed the highest predictive value (Wald 11.9; p<0.001) for future ACS.. Poststress EF added incremental prognostic value for the prediction of ACS.

Topics: Acute Coronary Syndrome; Adenosine Triphosphate; Aged; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; Coronary Artery Disease; Coronary Circulation; Exercise Test; Female; Humans; Hypertension; Japan; Kaplan-Meier Estimate; Male; Middle Aged; Multivariate Analysis; Myocardial Ischemia; Myocardial Perfusion Imaging; Myocardial Revascularization; Organophosphorus Compounds; Organotechnetium Compounds; Predictive Value of Tests; Proportional Hazards Models; Prospective Studies; Radiopharmaceuticals; Risk Assessment; Risk Factors; Stroke Volume; Thallium Radioisotopes; Time Factors; Treatment Outcome

Lower radiopharmaceutical activities are used for myocardial perfusion scintigraphy (MPS) in the UK than in other countries. There is no evidence to suggest that higher activities improve imaging or clinical outcome.. We undertook a multicentre study of the relationship between radiopharmaceutical activity and imaging outcome. Fifty-one patients with clinical referrals for MPS followed a 2-day protocol with an injection of 1,000 MBq (99m)Tc-tetrofosmin for each of the stress and rest images. ECG-gated acquisition was performed in three rotations occupying 25, 35 and 40% of a standard acquisition, and rotations were summed to simulate administered activities of 250, 400, 750 and 1,000 MBq. Each set of images was reported by an experienced physician who was blinded to all clinical information and to the simulated activity. Scores were assigned for image quality, low count, attenuation and reconstruction artefact, segmental tracer uptake, segmental and global defect classification, and confidence in the global classification. The images were reported twice to assess intra-observer variability.. Positive relationships were found between administered activity and overall image quality, observer confidence and intra-observer agreement of uptake score, and a negative relationship was found with low-count artefact. For the majority of comparisons, there was no additional improvement with increasing activity from 750 to 1,000 MBq. Intra-observer agreement was found to be better in female patients and in those below average body mass index.. We conclude that higher administered radiopharmaceutical activities lead to better quality images and improved surrogate parameters for clinical outcome, but that activities above 750 MBq may be unnecessary in average patients.

Topics: Aged; Coronary Artery Disease; Dose-Response Relationship, Drug; Female; Humans; Male; Organophosphorus Compounds; Organotechnetium Compounds; Radionuclide Imaging; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Statistics as Topic

Erectile dysfunction (ED) has been associated with a future risk of myocardial infarction, yet the findings on stress testing in men with ED and without previous coronary artery disease are unknown. Stress myocardial perfusion single-photon emission computed tomographic imaging (MPI) allows detection of coronary artery disease and predicts cardiovascular prognosis. Our goal was to determine the association between ED and findings at stress MPI testing in men without previous coronary artery disease. Five hundred seventy-five men without previous coronary artery disease referred for stress MPI were prospectively screened for ED with the validated International Index of Erectile Function. ED was present in 46% of subjects, and ED was associated with more mild (summed stress score >or=4) and severe (summed stress score >8) coronary artery disease and with more composite high-risk stress MPI findings (summed stress score >8, left ventricular ejection fraction <40%, transient ischemic dilation). In patients referred for exercise, ED was associated with a lower Duke treadmill score. On multivariate analysis, ED was found to be an independent predictor of a summed stress score >or=4, a summed stress score >8, and composite high-risk MPI findings. In conclusion, in men without known coronary artery disease referred for stress MPI testing, ED is associated with adverse prognostic indicators at MPI testing including coronary artery disease and high-risk MPI findings.

Topics: Adrenergic beta-Antagonists; Coronary Artery Disease; Coronary Circulation; Diabetes Mellitus; Erectile Dysfunction; Exercise Test; Heart; Humans; Male; Middle Aged; Multivariate Analysis; Organophosphorus Compounds; Organotechnetium Compounds; Prospective Studies; Radiopharmaceuticals; Severity of Illness Index; Smoking; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

CT angiography (CTA) offers a valuable alternative for the diagnosis of CAD but its value in the detection of functionally relevant coronary stenoses remains uncertain. We prospectively compared the accuracy of 64-slice CTA with that of myocardial perfusion imaging (MPI) using (99m)Tc-tetrofosmin-SPECT as the gold standard for the detection of functionally relevant coronary artery disease (CAD).. MPI and 64-slice CT were performed in 100 consecutive patients. CTA lesions were analysed quantitatively and area stenoses > or =50% and > or =75% were compared with the MPI findings.. In 23 patients, MPI perfusion defects were found (12 reversible, 13 fixed). A total of 399 coronary arteries and 1,386 segments was analysed. Eighty-four segments (6.1%) in 23 coronary arteries (5.8%) of nine patients (9.0%) were excluded owing to insufficient image quality. In the remaining 1,302 segments, quantitative CTA revealed stenoses > or =50% in 57 of 376 coronary arteries (15.2%) and stenoses > or =75% in 32 (8.5%) coronary arteries. Using a cut-off at > or =75% area stenosis, CTA yielded the following sensitivity, specificity, negative (NPV) and positive predictive value (PPV), and accuracy for the detection of any (fixed and reversible) MPI defect: by patient, 75%, 90%, 93%, 68% and 87%, respectively; by artery, 76%, 95%, 99%, 50% and 94%, respectively.. Sixty-four-slice CTA is a reliable tool to rule out functionally relevant CAD in a non-selected population with an intermediate pretest likelihood of disease. However, an abnormal CTA is a poor predictor of ischaemia.

Topics: Adult; Aged; Aged, 80 and over; Coronary Angiography; Coronary Artery Disease; Coronary Stenosis; Coronary Vessels; Female; Humans; Male; Middle Aged; Myocardium; Organophosphorus Compounds; Organotechnetium Compounds; Perfusion; Prospective Studies; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

The aim of this study was to investigate whether early (time 1, or T1) myocardial tetrofosmin imaging is feasible and as accurate in detecting coronary artery disease as is standard delayed (time 2, or T2) imaging.. One hundred twenty patients (100 men and 20 women; mean age +/- SD, 61 +/- 10 y) with anginal symptoms underwent tetrofosmin gated SPECT. Stress/rest T1 imaging was performed at 15 min and T2 at 45 min after injection. Image quality was visually evaluated using a 4-point scale (from 0 = poor to 3 = optimal). Myocardial perfusion analysis was performed on a 20-segment model using quantitative perfusion SPECT software, and reversible ischemia was scored as a summed difference score (SDS). Coronary angiography was performed within 1 mo on all patients, and stenosis of more than 50% of the diameter was considered significant.. Overall, quality was scored as optimal or good for 94% of T1 images and 95% of T2 images (P = not statistically significant). Heart, lung, liver, and subdiaphragmatic counts did not differ for stress and rest T1 and T2 imaging. A good linear relationship was seen between T1 and T2 SDS (r = 0.69; P < 0.0001), and Bland-Altman analysis showed good agreement between the 2 conditions. In terms of global diagnostic accuracy, areas under the receiver-operating-characteristic curve were comparable between T1 and T2 (0.80 vs. 0.81, P = not statistically significant). Discrepancies between T1 and T2 SDS were observed in 44% of patients (T1 - T2 SDS > 2). Linear regression analysis showed a good correlation between T1 and T2 SDS (r = 0.67; P < 0.0001), whereas the Bland-Altman method showed a shift in the mean value of the difference of +2.67 +/- 2.73. In patients with a T1 - T2 SDS of more than 2, areas under the receiver-operating-characteristic curves were significantly higher for T1 than for T2 images (0.79 vs. 0.70, P < 0.001).. T1 imaging is feasible and as accurate as T2 imaging in identifying coronary artery disease. However, in a discrete subset of patients, early acquisition strengthens the clinical message of defect reversibility by permitting earlier, more accurate identification of more severe myocardial ischemia.

Topics: Adult; Aged; Aged, 80 and over; Coronary Artery Disease; Feasibility Studies; Female; Gated Blood-Pool Imaging; Humans; Italy; Male; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Radiopharmaceuticals; Reproducibility of Results; Risk Assessment; Risk Factors; Sensitivity and Specificity; Tomography, Emission-Computed, Single-Photon

Topics: Clinical Trials as Topic; Coronary Artery Disease; Dobutamine; Exercise Test; Humans; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Radionuclide Imaging; Radiopharmaceuticals; Risk Assessment; Risk Factors; Vasodilator Agents; Ventricular Dysfunction, Left

Previous studies have shown a good outcome for patients who present with normal findings on stress myocardial perfusion imaging. Currently, the prognostic implications of a normal study in patients who have a history of coronary artery disease (CAD) are not clear. This study investigated the long-term prognosis after a normal finding on stress technetium-99m (Tc-99m)-tetrofosmin single-photon emission computed tomography in patients with a history of CAD. The study included 147 consecutive patients with a history of CAD (previous myocardial infarction and/or myocardial revascularization), who underwent exercise bicycle or high-dose dobutamine-atropine stress Tc-99m-tetrofosmin single-photon emission computed tomography, and had normal perfusion results during stress and at rest. Follow-up was completed in all patients. During a follow-up of 6.5 +/- 1.9 years, 20 patients (14%) died, 10 (7%) of whom died due to cardiac causes, and 12 (8%) had a nonfatal myocardial infarction. Annual cardiac death rates were 0.5% during the first 3 years of follow-up and 1.3% in the subsequent 3 years. Independent predictors of cardiac death were male gender, rate-pressure product at rest, and rate-pressure product at peak stress. In conclusion, patients who have a history of CAD have a very low cardiac death rate during the 3 years after a normal finding on stress Tc-99m-tetrofosmin single-photon emission computed tomography. Repeated testing should be reconsidered 3 years after the initial evaluation and when a change in symptoms or clinical condition occurs.

Topics: Aged; Blood Pressure; Coronary Artery Disease; Coronary Circulation; Echocardiography, Stress; Exercise Test; Female; Follow-Up Studies; Heart Rate; Humans; Male; Middle Aged; Multivariate Analysis; Myocardial Infarction; Myocardial Revascularization; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Radiopharmaceuticals; Sex Factors; Tomography, Emission-Computed, Single-Photon

Topics: Anticholesteremic Agents; Atorvastatin; Coronary Artery Disease; Coronary Circulation; Heptanoic Acids; Humans; Hypercholesterolemia; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Pyrroles; Radionuclide Imaging; Radiopharmaceuticals; Treatment Outcome

The aim of this study was to assess the accuracy of stress 99m technetium tetrofosmin myocardial perfusion imaging for the diagnosis of in stent stenosis (ISS).. We studied 72 patients who underwent exercise or dobutamine stress 99m technetium tetrofosmin imaging, 0.9+/-0.5 years after percutaneous coronary interventions in which stents were deployed. Coronary angiography was performed within 3 months of the stress test. ISS was defined as > or =50% stenosis in a coronary segment with previous stenting. Significant coronary artery disease (CAD) was defined as > or =50% stenosis within or outside the stented coronary segment.. The stent was deployed in 1 coronary artery in 52 patients, and in 2 coronary arteries in 20 patients (a total of 92 detected in 42 (58%) patients (51 stents). Reversible perfusion abnormalities were present in 34 of patients with ISS (sensitivity=81%, CI 70-94). Regional sensitivity for diagnosis of stenosis per stent was 76% (CI 65-88), specificity was 83% (CI 71-94) and accuracy was 79% (CI 69-85). Reversible perfusion abnormalities were detected in > or =2 vascular distributions in 15 of 22 patients with multi-vessel CAD and in 5 of 50 patients without (sensitivity for identifying multivessel CAD=68%, CI 50-89; specificity=90%, CI 82-98; and accuracy=83%, CI 75-90).. Stress 99m technetium tetrofosmin myocardial perfusion imaging is a useful non-invasive technique for the diagnosis of in stent stenosis and extent of CAD in patients with previous percutaneous coronary artery interventions.

Topics: Adrenergic beta-Agonists; Angioplasty, Balloon, Coronary; Coronary Angiography; Coronary Artery Disease; Coronary Circulation; Coronary Restenosis; Dobutamine; Exercise Test; Female; Follow-Up Studies; Humans; Male; Middle Aged; Myocardial Ischemia; Organophosphorus Compounds; Organotechnetium Compounds; Predictive Value of Tests; Radiopharmaceuticals; Research Design; Sensitivity and Specificity; Stents; Time Factors; Tomography, Emission-Computed, Single-Photon

When adenosine stress testing is performed, a vein is generally accessed in each arm. To determine whether the one-route infusion protocol, that is, infusion via one upper arm vein, is safe, myocardial perfusion imaging was performed during adenosine stress testing in patients with angina pectoris. Sixty-six consecutive patients (43 men, 68 +/- 11 years of age) with suspected coronary artery disease were enrolled in this study. For the stress test, adenosine was injected at 120 microg/kg/min for 6 minutes. Systolic blood pressure, diastolic blood pressure, and heart rate did not show any significant changes after injection of the adenosine and radioisotope (RI) tracer. Adverse events during infusion of the adenosine were seen in 42 (64%) patients and included chest discomfort/oppression in 17 (26%) and dyspnea/throat discomfort in 15 (23%). On the other hand, adverse events just after infusion of the RI tracer occurred in 5 (8%) patients and included chest oppression in 2 (3%) and dyspnea in 1 (2%). Almost all adverse events disappeared quickly without treatment. Therefore, we concluded that adenosine stress myocardial perfusion imaging using a one-route infusion protocol is safe and useful to do for patients unable to secure veins in both arms.

Topics: Adenosine; Adult; Aged; Aged, 80 and over; Angina Pectoris; Blood Pressure; Coronary Artery Disease; Heart; Heart Rate; Humans; Infusions, Intravenous; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radionuclide Imaging; Technetium Tc 99m Sestamibi

The aim of this study was to ascertain whether stress myocardial perfusion imaging can independently predict long-term mortality.. We studied 1,386 patients with known or suspected coronary artery disease by means of stress 99mTc-tetrofosmin myocardial perfusion tomography. The end point during follow-up was death from any cause. Mortality rates were compared with that in a reference population using calculated age- and gender-specific data in the general population.. Mean age was 60+/-11 years. There were 608 (44%) women. Perfusion abnormalities were fixed in 416 (30%) patients and reversible in 445 (32%) patients. During a mean follow-up of 6+/-1.9 years, 290 (21%) patients died. The annual mortality was 1.7% in patients with normal perfusion and 5.2% in patients with abnormal perfusion. Patients with multivessel distribution of perfusion abnormalities had the highest annual mortality (6.2%). The annual mortality in the reference population was 3.2%. In a multivariate analysis model, predictors of death were age [risk ratio (RR)=1.06, 95% CI 1.04-1.07], male gender (RR=2, CI 1.6-2.6), history of heart failure (RR=2.3, CI 1.8-3.1), diabetes mellitus (RR=2.1, CI 1.6-2.7), smoking (RR=1.8, CI 1.4-2.3), reversible perfusion defects (RR=1.8, CI 1.4-2.5) and fixed perfusion defects (RR=1.7, CI 1.3-2.1).. Myocardial perfusion abnormalities on stress 99mTc-tetrofosmin tomography are independently associated with long-term risk of death. The extent of perfusion abnormalities is a major determinant of mortality. The presence of normal perfusion is associated with a lower mortality compared with the general population.

Topics: Coronary Artery Disease; Exercise Test; Female; Humans; Male; Middle Aged; Netherlands; Organophosphorus Compounds; Organotechnetium Compounds; Perfusion; Prevalence; Prognosis; Proportional Hazards Models; Radionuclide Imaging; Radiopharmaceuticals; Reproducibility of Results; Risk Assessment; Risk Factors; Sensitivity and Specificity; Survival Analysis; Survival Rate; Vasodilator Agents

Transient ischemic dilatation (TID) of the left ventricle observed during single photon myocardial perfusion emission computed tomography (SPECT) is an important non-perfusion finding that may not only suggest underlying significant (usually multi-vessel) coronary artery disease (CAD) but also an independent prognostic factor of adverse outcomes regardless of abnormal or normal perfusion finding. We present a patient with no significant epicardial coronary disease who had significant TID and considerable decrease in the left ventricular ejection fraction with left ventricular dilatation after a rest-stress Tc-99 tetrofosmin SPECT study in the setting of severe aortic stenosis. With the advent of gated SPECT imaging the additive value of determining rest and post stress EF, as demonstrated in this case, aided in the recognition of TID and transient decrease in the left ventricular ejection fraction. These are not necessarily related to obstructive epicardial coronary disease, but are a result of severe aortic valve disease causing subendocardial ischemia in the setting of multilple other non-ischemic etiologies of TID such as left ventricular hypertrophy and diabetes mellitus.

Topics: Adenosine; Aortic Valve; Aortic Valve Stenosis; Coronary Artery Disease; Coronary Vessels; Exercise Test; Female; Humans; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Stroke Volume; Tomography, Emission-Computed, Single-Photon; Vasodilator Agents; Ventricular Dysfunction, Left

Earlier studies have suggested a modest accuracy of stress thallium 201 myocardial perfusion imaging (MPI) for the diagnosis of coronary artery disease (CAD) in women. The accuracy of stress MPI with technetium 99m tetrofosmin has not been studied in women. The aim of this study was to assess the accuracy of stress Tc-99m tetrofosmin MPI for the diagnosis and localization of CAD in women.. We studied 88 women who underwent exercise or dobutamine stress Tc-99m tetrofosmin tomography and coronary angiography within 3 months. Significant CAD was defined as a stenosis 50% or greater in diameter in at least 1 major epicardial coronary artery. Myocardial perfusion abnormalities were detected in 44 of 53 patients with significant CAD and in 7 of 35 patients without significant CAD (overall sensitivity, 83% [95% confidence interval (CI), 73%-93%]; specificity, 80% [95% CI, 67%-93%]; and accuracy, 82% [95% CI, 74%-90%]). The sensitivity was 72% (18/25) in patients with single-vessel CAD and 93% (26/28) in patients with multivessel CAD. Perfusion abnormalities were detected in 2 or more vascular distributions in 20 of 28 patients with multivessel CAD and in 4 of 60 patients without multivessel CAD (sensitivity for the identification of multivessel CAD, 71% [95% CI, 55%-88%]; specificity, 93% [95% CI, 86%-98%]; and accuracy, 86% [95% CI, 79%-93%]). The sensitivity, specificity, and accuracy were 82%, 84%, and 83%, respectively, for the diagnosis of CAD in the left anterior descending artery; 77%, 84%, and 81%, respectively, for CAD in the right coronary artery; and 74%, 80%, and 78%, respectively, for CAD in the left circumflex artery.. Stress Tc-99m tetrofosmin MPI is an accurate noninvasive technique for the diagnosis and localization of CAD in women.

Topics: Aged; Coronary Angiography; Coronary Artery Disease; Coronary Stenosis; Female; Humans; Middle Aged; Myocardial Ischemia; Organophosphorus Compounds; Organotechnetium Compounds; Radionuclide Imaging; Radiopharmaceuticals; Reproducibility of Results; Tomography, X-Ray Computed

Topics: Aged; Coronary Angiography; Coronary Artery Disease; Heart Ventricles; Humans; Male; Myocardium; Organophosphorus Compounds; Organotechnetium Compounds; Perfusion; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon; Ventricular Function, Right

99mTc-tetrofosmin and 99mTc-sestamibi are approved tracers for myocardial perfusion studies. Recently, a 99mTc-MIBI preparation from a different manufacturer (99mTc-cardiospect-MIBI) has been introduced to the market. Therefore, the aim of this study was the evaluation of 99mTc-tetrofosmin as well as of two different 99mTc-labeled MIBI tracers with regard to differences in imaging quality under resting conditions.. Sixty patients (mean age 63.8 years +/- 1.25) with known or suspected coronary artery disease but without evidence of rest-ischemia were included. Twenty patients in each group were examined by a two-day-rest-stress protocol using the three 99mTc-labeled tracers. Visual analysis of all images was performed by two experienced physicians blinded with regard to the applied tracer. Regions of interest (ROI) were defined over the heart, lung and whole body only in the rest imaging in order to calculate heart-to-lung, lung-to-whole body-, and heart-to-whole body-ratios.. The heart-to-lung ratio was statistically significant higher for 99mTc-cardiospect-MIBI as compared to 99mTc-sestamibi as well as to 99mTc-tetrofosmin. Furthermore, a significantly higher heart-to-lung ratio was found for 99mTc-sestamibi as compared to 99mTc-tetrofosmin. The heart-to-whole body-ratio and the lung-to-whole body-ratio were equivalent between all tracers. Visual analysis revealed only slight differences regarding image quality between all tracers.. ROI analysis surprisingly revealed a significant higher myocardial uptake and consequently a higher heart-to-lung ratio for 99mTc-cardiospect-MIBI. Whether this leads to a better visual image quality has to be evaluated in future studies with larger study populations as well as semiquantitative segmental analysis of the myocardial perfusion images.

Topics: Coronary Artery Disease; Female; Heart; Humans; Injections, Intra-Arterial; Lung; Male; Metabolic Clearance Rate; Middle Aged; Myocardium; Organophosphorus Compounds; Organotechnetium Compounds; Perfusion; Positron-Emission Tomography; Radiopharmaceuticals; Rest; Technetium Tc 99m Sestamibi; Tissue Distribution; Ventricular Dysfunction, Left; Whole Body Imaging

Technetium-99m-tetrofosmin single-photon emission computed tomography at rest is practical for routine assessment of viability in patients with ischemic cardiomyopathy. However, underestimation of viability may occur compared with 18F-fluorodeoxyglucose single-photon emission computed tomography, especially in the inferoposterior and septal regions.

Topics: Coronary Artery Disease; Female; Fluorodeoxyglucose F18; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Predictive Value of Tests; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

Topics: Aged; Coronary Artery Disease; Diagnosis, Differential; Exercise Test; Female; Heart Aneurysm; Humans; Organophosphorus Compounds; Organotechnetium Compounds; Radionuclide Imaging; Radiopharmaceuticals; Ventricular Dysfunction, Left; Wounds, Gunshot

To evaluate the reproducibility and operator dependence for the quantitative regional left ventricular functional parameters (LVFP) assessed by Cedars-Sinai's Quantitative automated gated SPECT (QGS) software.. The QGS algorithm was reviewed in detail and potential operator dependencies were defined. Series of prototypes were selected, consisting of (a) normal perfusion, (b) perfusion defects in all perfusion regions, (c) perfusion studies of patients with angiographic confirmed normal coronary arteries, proximal (>or=70% stenoses) single and multiple vessel disease, and (d) spurious activity in close proximity. While defining and re-orienting the volume containing the left ventricle, the operator adjusted 8 variables/degrees of freedom (DF). The software was used without further operator interventions. Results were expressed as a coefficient of variation (COV). Separate COV were calculated per distinct DF. A segment was considered not robust when the COV did exceed 20% in a single DF, 15% in at least 2 DF, or 10% in at least 3 DF.. Regional left ventricular EF and volumes showed excellent reproducibility. Normal perfusion and the vessel disease prototypes showed an excellent COV (for all re-orientation steps [33/prototype]) mostly below 5% for LVFP. However, regional wall motion and thickening became less reliable in the presence of large perfusion defects or artifacts.. Quantitative estimates for regional left ventricular functional data show excellent reproducibility using automated gated SPECT. However, there may be substantial operator dependency in the presence of large defects or spurious activity in close proximity.

Topics: Algorithms; Coronary Artery Disease; Coronary Stenosis; Echocardiography, Stress; Exercise Test; Gated Blood-Pool Imaging; Humans; Image Processing, Computer-Assisted; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Software; Stroke Volume; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

Angina pectoris is a major symptom associated with myocardial ischemia. The aim of this study was to find whether stress myocardial perfusion imaging can independently predict mortality in patients with angina.. We studied 455 patients with stable angina pectoris by exercise or dobutamine stress (99m)Tc-tetrofosmin myocardial perfusion tomographic imaging. An abnormal finding was defined as a reversible or fixed perfusion abnormality. The endpoint during follow-up was death from any cause.. Mean age was 60+/-10 y. There were 266 men (58% of the patients). Myocardial perfusion was normal in 137 patients (30%). Perfusion abnormalities were reversible in 167 patients and fixed in 151 patients. During a mean follow-up of 6+/-1.7 y, 93 patients (20%) died. The annual mortality rate was 1.5% in patients with normal perfusion and 4.5% in patients with abnormal perfusion. Patients with a multivessel distribution of perfusion abnormalities had a higher annual death rate than patients with abnormalities in a single-vessel distribution (5.1% vs. 3.7%). In a multivariate analysis model, independent predictors of death were age (risk ratio, 1.05; 95% confidence interval [CI], 1.03-1.08), the male sex (risk ratio, 2.1; CI, 1.3-3.4), diabetes (risk ratio, 2.2; CI, 1.4-3.5), heart failure (risk ratio, 2.7; CI, 1.6-4.5), smoking (risk ratio, 1.7; CI, 1.1-2.6), reversible perfusion abnormalities (risk ratio, 1.9; CI, 1.1-2.8), and fixed perfusion abnormalities (risk ratio, 2; CI, 1.2-3.1).. Stress 99mTc-tetrofosmin myocardial perfusion imaging provides independent information for predicting mortality in patients with stable angina pectoris. Both reversible and fixed defects are associated with an increased risk of death. The extent of stress perfusion abnormalities is a major determinant of mortality. Patients with normal perfusion have a low mortality rate during long-term follow-up.

Topics: Adult; Aged; Angina Pectoris; Coronary Artery Disease; Disease-Free Survival; Female; Humans; Male; Middle Aged; Multivariate Analysis; Organophosphorus Compounds; Organotechnetium Compounds; Perfusion; Prognosis; Proportional Hazards Models; Radiopharmaceuticals; Risk; Risk Factors; Time Factors; Tomography, Emission-Computed, Single-Photon

This study reports an evaluation of coronary arterial blood flow patterns in patients with diabetes mellitus and healthy subjects using magnetic resonance coronary angiography (MRCA). Twenty patients with diabetes mellitus (DM group) and 20 healthy subjects (N group) were studied using MRCA and myocardial SPECT images using (99m)Tc-tetrofosmin (TF). The rate of change in myocardial TF uptake was measured during a 1-day protocol of exercise and rest. Initial and delayed exercise single photon emission computed tomography (SPECT) images were acquired 30 min and 3 h after injection (370 MBq of TF) (TF1 and TF2, respectively). Thereafter, 740 MBq of TF was administered intravenously, again, and resting SPECT images (TF3) were acquired 30 min later. The myocardial counts of these three points of acquisition were defined, and the rate of change of myocardial TF uptake between exercise and rest was determined. The % increase in uptake was significantly lower in the DM group than in the N group in all myocardial segments. The average coronary arterial diastolic velocity determined using MRCA was slightly lower in the DM group than in the N group, and the average systolic peak velocity (ASPV) was slightly greater in the DM group than in the N group, although these values were not statistically significant. The diastolic/systolic velocity ratio (DSVR) in the DM group was significantly lower than that in the N group ( P < 0.05). There was a significant correlation between DSVR and % uptake increase ( r = 0.605, P < 0.05). These results indicate that the measurements made using MRCA and the % uptake increase measured using TF myocardial scintigraphy represent a potentially useful noninvasive method for diagnosing microvascular dysfunction in diabetic patients.

Topics: Blood Flow Velocity; Case-Control Studies; Coronary Artery Disease; Coronary Circulation; Diabetes Mellitus; Exercise Test; Female; Heart; Humans; Magnetic Resonance Angiography; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon

Topics: Aged; Breast Neoplasms; Coronary Artery Disease; Female; Heart; Humans; Incidental Findings; Mastectomy, Modified Radical; Neoplasm Recurrence, Local; Organophosphorus Compounds; Organotechnetium Compounds; Radionuclide Imaging; Radiopharmaceuticals

Cardiovascular magnetic resonance (CMR) perfusion can accurately detect coronary artery disease (CAD). However, the absence of efficient, easy-to-use and reliable image analysis software is an obstacle to its introduction into clinical practice. The aim of this study was to evaluate new color-encoded semiautomatic software for analysis of first-pass CMR perfusion in comparison to tetrofosmin myocardial single photon emission computed tomography (SPECT), using X-ray angiography as the standard of truth for the detection of CAD.. Thirty-two patients underwent both SPECT and CMR perfusion at rest and adenosine stress. Twenty of these patients also underwent X-ray angiography. Off-line CMR image analysis consisted of six steps to generate a color display of the myocardial perfusion reserve index (MPRI). The MPRI color-maps were analyzed visually and compared to SPECT.. In comparison to X-ray angiography overall accuracy was 87% for CMR and 77% for SPECT perfusion to detect significant CAD (stenosis > or =70%). In comparison with SPECT sensitivity was 80%, specificity 91%, and the overall agreement 89% for CMR.. Post-processing of CMR perfusion data using new semiautomatic software to generate and display the MPRI visually as color-encoded images is feasible and fast. In this study it yielded higher accuracy than SPECT to detect significant CAD on X-ray angiography. Correlation between SPECT and CMR accuracy for detection of perfusion defects was high. This method may accelerate the time-consuming analysis of CMR perfusion data, thus enabling a more widespread clinical utility.

Topics: Adenosine; Aged; Aged, 80 and over; Coronary Angiography; Coronary Artery Disease; Female; Humans; Image Processing, Computer-Assisted; Magnetic Resonance Angiography; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Sensitivity and Specificity; Software; Tomography, Emission-Computed, Single-Photon; Vasodilator Agents; X-Rays

In order to evaluate the diagnostic efficacy of the 1-day separate acquisition dual-isotope single-photon emission computed tomography (SPECT) protocol, using 201Tl for the rest and 99mTc-tetrofosmin for the stress images, a consecutive series of patients with suspected or known coronary artery disease (CAD) was studied that also underwent coronary angiography.. The results of myocardial SPECT, using a semi-quantitative visual analysis, were acquired in 123 patients and compared with the results of coronary angiography. Sensitivity and specificity were calculated, using thresholds of > or = 50 and > or = 70% stenosis. As an alternative for specificity, the normalcy rate was determined in a separate group of 87 patients with a < 5% pre-test likelihood of CAD.. The prevalence of CAD using > or =50 and > or = 70% stenosis was 88 and 78%, respectively. The sensitivity for detection of patients with > or = 50 and > or = 70% stenosis was 94 and 97%, respectively while specificity was 62 and 59%, respectively. The high rate of false positive perfusion defects resulting in a low specificity could be explained by specific clinical issues. However, the routine assessment with additional clinical and electrocardiographic data resulted in a correct interpretation of most of the false positive perfusion defects. The positive predictive value was 92 and 85% and the negative predictive value 46 and 77%, using thresholds of > or = 50 and > or = 70% stenosis, respectively. The normalcy rate was 91%.. The one-day separate acquisition rest 201Tl/stress 99mTc-tetrofosmin SPECT protocol is an efficient procedure for myocardial perfusion scintigraphy with high sensitivity for detection of CAD. Specific clinical issues caused a low value for specificity. Therefore, clinical information and knowledge of the electrocardiogram is essential for a correct interpretation of SPECT images.

Topics: Adenosine; Adult; Aged; Aged, 80 and over; Cardiomyopathies; Coronary Angiography; Coronary Artery Disease; Echocardiography; Exercise Test; False Positive Reactions; Female; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Predictive Value of Tests; Prevalence; Radiopharmaceuticals; Risk Factors; Sensitivity and Specificity; Statistics as Topic; Stroke Volume; Tomography, Emission-Computed, Single-Photon; Vasodilator Agents

Detection of myocardial perfusion abnormalities using Tc-99m tetrofosmin was evaluated for sensitivity and specificity compared to coronary angiography. Between January 1996 and January 1998, exercise stress tests and myocardial scintigraphy were performed in 58 patients, followed by coronary angiography within 2 months. There were 48 males and 10 females, aged 33 to 72 years (mean, 57 years). The sensitivity and specificity of exercise stress tests were 64% and 68%, respectively, while the sensitivity and specificity of Tc-99m tetrofosmin scans were 88% and 75%, respectively, compared to angiography. For Tc-99m tetrofosmin scans, the sensitivity was 78% for the left anterior descending artery, 66% for the left circumflex artery, and 76% for the right coronary artery; specificity was 74% for the left anterior descending artery, 90% for the left circumflex artery, and 75% for the right coronary artery. It was concluded that Tc-99m tetrofosmin allowed high-quality myocardial perfusion imaging with results comparable to those obtained using thallium-201 chloride.

Topics: Adult; Aged; Coronary Angiography; Coronary Artery Disease; Evaluation Studies as Topic; Exercise Test; Female; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Prospective Studies; Radionuclide Imaging; Radiopharmaceuticals; Sensitivity and Specificity; Thallium Radioisotopes

Stress nuclear imaging is the noninvasive technique currently used to detect coronary artery disease (CAD) in dialysis patients. Stress echocardiography is recognized as an alternative to stress nuclear imaging for the general population. The aim of this study is to assess the diagnostic accuracy of stress echocardiography for detecting myocardial ischemia in hemodialysis patients.. Stress echocardiography and stress technetium-99m-tetrofosmin (Myoview; Amersham International Plc) imaging were performed simultaneously for 66 asymptomatic hemodialysis patients in a single session, using a combination of high-dose dipyridamole and symptom-limited exercise. Coronary angiography was performed in 44 patients with at least one abnormal noninvasive test result or who were considered high-risk despite normal noninvasive test results.. Results for stress echocardiography were abnormal in 15 patients (22%); stress Myoview, in 14 patients (21%); and coronary angiography, in 12 patients (18%). The sensitivity of stress echocardiography for detecting myocardial ischemia (defined as stress Myoview defect) was 86%; specificity, 94%; positive predictive value, 80%; negative predictive value, 96%; and overall accuracy, 92%. The sensitivity of stress echocardiography for detecting CAD (defined as abnormal coronary angiography result) was 83%; specificity, 84%; positive predictive value, 67%; negative predictive value, 93%; and overall accuracy, 84%. Stress echocardiography and stress Myoview did not differ significantly in overall accuracy for detecting CAD (84% versus 91%; P = not significant).. In hemodialysis patients, combined dipyridamole-exercise echocardiography is an accurate method to detect both myocardial ischemia and CAD and represents an alternative to stress nuclear imaging.

Topics: Adult; Aged; Coronary Angiography; Coronary Artery Disease; Dipyridamole; Echocardiography, Stress; Exercise Test; Female; Humans; Male; Middle Aged; Myocardial Ischemia; Organophosphorus Compounds; Organotechnetium Compounds; Radionuclide Ventriculography; Radiopharmaceuticals; Renal Dialysis; Risk Assessment; Sensitivity and Specificity; Vasodilator Agents

99mTc-Tetrofosmin is a recently introduced radioactive isotope for the assessment of myocardial perfusion. Data regarding the prognostic value of stress imaging using this isotope are scarce. The aim of this study was to assess the prognostic value of dobutamine-atropine (99m)Tc-tetrofosmin SPECT for the prediction of late cardiac events in patients with known or suspected coronary artery disease.. A total of 721 consecutive patients with limited exercise capacity underwent dobutamine-atropine stress (99m)Tc-tetrofosmin SPECT. Follow-up was successful in 719 of 721 patients (99.7%). Twenty-eight patients who underwent early revascularization were excluded.. Myocardial perfusion abnormalities were detected in 381 patients (55%) and included fixed defects in 190 patients (27%) and reversible defects 191 patients (28%). During a mean follow-up period of 37 +/- 17 mo, there were 150 deaths (22%), of which 62 (41%) were attributed to cardiac causes. Nonfatal myocardial infarction occurred in 23 patients (3%), and late (>3 mo) coronary revascularization was performed on 21 patients (3%). The cardiac death rate was 1%/y in patients with a normal scan and 5.1%/y in patients with an abnormal scan (P < 0.0001). In a multivariable Cox proportional-hazards model, the presence of abnormal perfusion was independently associated with an increased risk of cardiac death, after adjusting for clinical and stress test data (hazard ratio, 8.2; 95% confidence interval, 3.2-21).. Dobutamine-atropine stress (99m)Tc-tetrofosmin SPECT is a useful imaging method for distinguishing patients at high and low risk of future cardiac events. The presence of perfusion abnormalities provides incremental prognostic information to clinical, stress electrocardiographic, and hemodynamic data.

Topics: Atropine; Coronary Artery Disease; Dobutamine; Female; Humans; Logistic Models; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Predictive Value of Tests; Prognosis; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon

Hypertensive patients with complete left bundle branch block who experience chest pain present special problems in the radionuclide diagnosis of coronary artery disease (CAD). The aim of this study was to assess the utility of Tc-99m tetrofosmin SPECT for the diagnosis of CAD in 35 hypertensive patients with left bundle branch block hospitalized for chest pain.. Images were analyzed semiquantitatively for the presence of both fixed or reversible perfusion defects (method A) or only reversible defects (method B) in the distribution of the left anterior descending artery (LAD) territory. Perfusion defects observed in the territory of any other coronary artery were always considered. Thirty-five patients without infarction underwent adenosine Tc-99m tetrofosmin SPECT, transthoracic echocardiography, and coronary angiography.. The mean left ventricular ejection fraction was calculated as 39.9% +/- 11.6%, and the prevalence of CAD was 29%. The sensitivity of SPECT was identical for the two methods at 89%. The specificity increased 19% with method A and 54% with method B. The positive predictive value remained unsatisfactorily low with both methods (27% for method A and 40% for method B), and the negative predictive value improved from 83% with method A to 93% with method B.. Only reversible perfusion defects in the LAD territory should be considered significant for CAD, and these patients should undergo coronary angiography. Reversible or fixed perfusion defects in the left circumflex and right coronary artery territories should be evaluated according to other clinical parameters (global left ventricular ejection fraction, extension of perfusion defects). The highly negative predictive value of adenosine SPECT could help in the exclusion of CAD.

Topics: Adenosine; Bundle-Branch Block; Chest Pain; Coronary Angiography; Coronary Artery Disease; Echocardiography; Female; Heart Septal Defects; Humans; Hypertension; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Predictive Value of Tests; Radiopharmaceuticals; Sensitivity and Specificity; Stress, Physiological; Tomography, Emission-Computed, Single-Photon