technetium-tc-99m-tetrofosmin and Ventricular-Dysfunction--Left

The assessment of myocardial viability has become an important aspect of the diagnostic and prognostic work-up of patients with ischemic cardiomyopathy. Although revascularization may be considered in patients with sufficient viable myocardium, patients with predominantly scar tissue should be treated medically. Patients with left ventricular dysfunction who have viable myocardium are the patients at highest risk because of the potential for ischemia but at the same time benefit most from revascularization. It is important to identify viable myocardium in these patients, and radionuclide myocardial scintigraphy is an excellent tool for this. Single-photon emission computed tomography perfusion scintigraphy (SPECT), whether using (201)thallium, (99m)Tc-sestamibi, or (99m)Tc-tetrofosmin, in stress and/or rest protocols, has consistently been shown to be an effective modality for identifying myocardial viability and guiding appropriate management. Metabolic and perfusion imaging with positron emission tomography (PET) radiotracers frequently adds additional information and is a powerful tool for predicting which patients will have an improved outcome from revascularization. New techniques in the nuclear cardiology field, like attenuation corrected SPECT, dual isotope simultaneous acquisition (DISA) SPECT and gated FDG PET are promising and will further improve the detection of myocardial viability. Also the combination of multislice computed tomography scanners with PET opens possibilities of adding coronary calcium scoring and non-invasive coronary angiography to myocardial perfusion imaging and quantification. Evaluation of the clinical role of these creative new possibilities warrants investigation.

Topics: Coronary Disease; Fluorodeoxyglucose F18; Humans; Myocardium; Organophosphorus Compounds; Organotechnetium Compounds; Positron-Emission Tomography; Radiopharmaceuticals; Rubidium Radioisotopes; Technetium Tc 99m Sestamibi; Thallium Radioisotopes; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

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

The noninvasive assessment of myocardial viability in patients with coronary artery disease and depressed left ventricular function has proven clinically useful for identifying those patients with ischemic cardiomyopathy who benefit most from coronary revascularization. Thallium-201 (201Tl) imaging at rest has been the radionuclide imaging technique most often utilized for distinguishing viable myocardium from scar. However, new technetium-99m (99mTc) perfusion agents such as 99mTc-sestamibi and 99mTc-tetrofosmin have emerged as alternatives to 201Tl for imaging of regional myocardial perfusion. Whether these new agents, which have better physical properties for imaging with a gamma camera than 201Tl, are valid for use in assessing myocardial viability is still uncertain. Recent clinical studies have demonstrated that these agents, when imaged using quantitative SPECT, can identify patients with myocardial hibernation who exhibit improved regional systolic function following revascularization. Experimental laboratory studies have shown that the uptake of 99mTc-sestamibi and 99mTc-tetrofosmin in ischemic myocardium is only slightly lower than the uptake of 201Tl. These 99mTc-labeled agents remain bound intracellularly in mitochondria of viable myocytes under conditions of myocardial stunning and short-term hibernation, producing severe myocardial asynergy. With respect to determination of viability, the inferior wall region is at times problematic since attenuation of 99mTc-sestamibi and 99mTc-tetrofosmin is greatest in this area. Demonstration of preserved systolic thickening on ECG-gated SPECT images is indicative of viability in the instance of decreased regional 99mTc counts due to attenuation and not scar. Administration of nitrates prior to tracer injection improves the sensitivity for identifying viable myocardial segments using rest imaging with 99mTc-sestamibi or 99mTc-tetrofosmin. Thus, it appears that the new 99mTc perfusion imaging agents can be successfully employed for the determination of myocardial viability in the setting of severe regional dysfunction and chronic coronary artery disease. The greater the myocardial uptake of these agents in the resting state, the greater the probability of improved systolic function after coronary revascularization.

Topics: Animals; Coronary Disease; Electrocardiography; Humans; Myocardial Reperfusion; Myocardium; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Technetium Tc 99m Sestamibi; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

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

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

We hypothesized that the severity of resting perfusion abnormalities assessed by the summed rest score (SRS) would be associated with a higher rate of adverse outcomes in patients with heart failure (HF) and reduced left ventricular (LV) ejection fraction (EF).. A subset of 240 subjects from HF-ACTION underwent resting technetium-99m tetrofosmin-gated single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI). Images were evaluated using a 17-segment model to derive the SRS and additional nuclear variables.. After adjusting for prespecified covariates, SRS was significantly associated with the primary end point (hazard ratio 0.98, 95% confidence interval [CI] 0.97-1.00, P = .04), with a higher SRS corresponding to lower risk of an event. This association was not present in the unadjusted analysis. The relationship between SRS and the primary outcome was likely due to a higher event ratein patients with ischemic HF and a low SRS. The LV phase SD was not predictive of the primary outcome (hazard ratio 1.00, 95% confidence interval 0.99-1.01, P = .49). In a post hoc analysis, nuclear variables provided incremental prognostic information when added to clinical information (P = .006).. Gated SPECT MPI provides important information in patients with HF and reduced LVEF. In the adjusted analysis, SRS has an unexpected relationship with the primary end point. Phase SD was not associated with the primary end point. Rest-gated SPECT MPI provides incrementally greater prognostic information than clinical information alone.

Topics: Aged; Female; Heart Failure; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Radiopharmaceuticals; Stroke Volume; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

Early diagnosis and initiating treatment of cardiac sarcoidosis are essential because cardiac involvement is an important prognostic factor. Although there are many reports on the diagnosis of cardiac sarcoidosis, the literature on predicting the efficacy of steroid therapy is very limited. The purposes of this study were to investigate the myocardial washout of (99m)Tc-tetrofosmin (TF), and to evaluate the predictability of left ventricular (LV) functional recovery after steroid therapy in patients with cardiac sarcoidosis.. We performed TF-gated SPECT and echocardiography for ten patients with cardiac sarcoidosis before and after initiating steroid therapy. SPECT images were acquired at 30 min (early images) and 3 h (delayed images) after injection. We calculated the total defect score (TDS) and left ventricular ejection fraction (LVEF). The washout score (WOS) was considered as the difference between the early and delayed TDS. In addition, we defined DeltaLVEF as the change in LVEF after initiating steroid therapy. Furthermore, we analyzed the regional TF myocardial uptake (%uptake) and the regional LV function (wall thickness, WT) by the 20-segment model on polar maps as regional indices. The regional washout (RWO) was defined as the change in %uptake between the early and delayed images in TF SPECT before the therapy. We calculated the improvement factor of the regional LV function as DeltaWT (WT after initiating therapy - WT before the therapy) and investigated the relationships among the indices.. We observed WO in 6 of 10 patients (60%). Decreased WT on echocardiography was observed in only 2 of 6 patients (33.3%) in the WO(+) group and in all 4 patients (100%) in the WO(-) group (p < 0.05). WOS before initiating steroid therapy exhibited a good correlation with DeltaLVEF (r = 0.685, p < 0.05). In the regional analysis, %uptake in the early images and delayed images before therapy did not significantly correlate with DeltaWT. In contrast, RWO before therapy was well correlated with DeltaWT (r = 0.435, p < 0.05).. Our preliminary study shows that there is a relationship between washout of (99m)Tc-tetrofosmin and the LV functional recovery after steroid therapy in patients with cardiac sarcoidosis.

Topics: Cardiomyopathies; Echocardiography; Female; Heart; Humans; Male; Middle Aged; Myocardium; Organophosphorus Compounds; Organotechnetium Compounds; Recovery of Function; Sarcoidosis; Steroids; Tomography, Emission-Computed, Single-Photon; Treatment Outcome; Ventricular Dysfunction, Left

Magnetic resonance imaging (MRI) is often considered to be the gold standard in measuring left ventricular function and volumes. The aim of this study was to assess the agreements between standard echocardiography (standard echo), contrast echocardiography (contrast echo), single-photon emission computed tomography (SPECT), and MRI in the determination of left ventricular ejection fraction (EF) and end-diastolic volumes (EDV) in patients treated for acute ST-elevation myocardial infarction (STEMI).. Standard echo, contrast echo, SPECT and MRI were performed on the same day, 3 months after STEMI in 150 patients participating in the NORwegian Study on District Treatment of ST-Elevation Myocardial Infarction (NORDISTEMI). Bland-Altman analysis of EF measured by all four imaging modalities showed generally low mean differences but wide limits of agreement. The mean EDV difference, however, was consistently higher when MRI was compared with standard echo (54.9 mL), contrast echo (41.7 mL) and SPECT (54.6 mL), and the limits of agreement were wider. The mean EDV differences between contrast echo vs. standard echo, SPECT vs. standard echo and contrast echo vs. SPECT were small.. Our data suggest that all four imaging modalities measured EF closely similar after STEMI as demonstrated by a very small bias. The limits of agreement were however wide. EDV measured by MRI was consistently higher when compared with the other methods which may be caused by different tracing-methods and imaging principles. As echocardiography is preferable from a cost-benefit point of view, further analysis would be needed to clarify the nature of such differences.

Topics: Contrast Media; Echocardiography; Female; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Myocardial Infarction; Organophosphorus Compounds; Organotechnetium Compounds; Prospective Studies; Radiopharmaceuticals; Statistics, Nonparametric; Thrombolytic Therapy; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

Usefulness of diastolic dysfunction after adenosine stress for detecting coronary stenosis has not been defined. The diagnostic accuracy of a combination of myocardial perfusion and diastolic function, as defined by prolongation of time to peak-filling rate (TTPF)/R-R and myocardial perfusion alone for the detection of coronary restenosis, was evaluated..  We used rest (201)Tl/ adenosine stress (99m)Tc-tetrofosmin myocardial perfusion singlephoton emission computed tomography (SPECT) in 70 patients. Patients were divided into the following 4 groups: 20 patients with normal SPECT without stent (Control group), 20 patients showing normal SPECT without coronary restenosis (Group 1), 16 patients showing significant coronary restenosis and myocardial ischemia (Group 2a) and 14 patients showing significant coronary restenosis without myocardial ischemia (Group 2b). The TTPF, which was calculated by quantitative gated SPECT (QGS)/R-R, was not different between after stress and at rest in Control group (0.18±0.02 vs 0.19±0.04, P=NS). The TTPF/R-R after stress was significantly lower than that at rest in Group 1 (0.17±0.02 vs 0.18±0.03, P<0.05), but TTPF/R-R after stress was significantly higher than that at rest in Groups 2a and 2b (0.22±0.03 vs 0.16±0.03, P<0.001 in Group 2a and 0.19±0.02 vs 0.16±0.02, P<0.001 in Group 2b, respectively). Diagnostic accuracy improved from 72% to 92% when prolongation of TTPF/R-R was taken into account (P<0.001).. Diastolic dysfunction after stress was an accurate marker for detecting significant restenosis following stent implantation.

Topics: Adenosine; Aged; Anti-Arrhythmia Agents; Coronary Restenosis; Electrocardiography; Exercise Test; Female; Humans; Male; Myocardial Reperfusion; Organophosphorus Compounds; Organotechnetium Compounds; Radiography; Radiopharmaceuticals; Stents; Thallium Radioisotopes; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

There are currently limited data on the relationships between resting perfusion abnormalities, left ventricular ejection fraction (LVEF), New York Heart Association (NYHA) functional class, and exercise capacity as defined by peak VO(2) and 6-minute walk test in patients with heart failure (HF) and reduced LVEF. Furthermore, the association between resting perfusion abnormalities and left ventricular dyssynchrony is currently unknown. This article addresses the Heart Failure and A Controlled Trial Investigating Outcomes of Exercise TraiNing (HF-ACTION) gated SPECT imaging (gSPECT) substudy baseline results.. HF-ACTION was a multicenter, randomized controlled trial of aerobic exercise training versus usual care in 2,331 stable patients with LVEF of < or = 35% and NYHA class II to IV HF symptoms treated with optimal medical therapy. Subjects enrolled in the HF-ACTION substudy underwent resting Tc-99m tetrofosmin gSPECT at baseline (n = 240). Images were evaluated for extent and severity of perfusion abnormalities using a 17-segment and a 5-degree gradation severity score (summed rest score [SRS]). Left ventricular function and dyssynchrony were assessed using validated available commercial software.. The average age of patients enrolled was 59, 69% were male, 63% were white, and 33% were African American. Of the 240 participants, 129 (54%) were ischemic and 111 (46%) were nonischemic in etiology. The median LVEF by gSPECT for the entire cohort was 26%. Among the nuclear variables, there was a modest correlation between LVEF and SRS (r = -0.31, P < .0001) and there were stronger correlations between phase SD and SRS (r = 0.66, P < .0001) as well as phase SD and LVEF (r = -0.50, P < .0001). Patients with NYHA class III symptoms had more severe and significant degrees of dyssynchrony (median phase SD 54 degrees ) than those with NYHA class II symptoms (median phase SD 39 degrees, P = .001). Patients with an ischemic etiology had a higher SRS (P < .0001) and significantly more dyssynchrony (P < .0001) than those who were nonischemic. However, there was no difference in LVEF or objective measures of exercise capacity between these groups. With respect to peak VO(2), there was a weak correlation with LVEF (r = 0.18, P = .006) and no correlation with SRS (r = -0.04, P = 0.59) or with dyssynchrony (r = -0.13, P = .09). A weak but statistically significant correlation between SRS and 6-minute walk was observed (r = -0.15, P = .047).. Gated SPECT imaging can provide important information in patients with HF due to severe LV dysfunction including quantitative measures of global systolic function, perfusion, and dyssynchrony. These measurements are modestly but significantly related to symptom severity and objective measures of exercise capacity.

Topics: Aged; Arrhythmias, Cardiac; Data Collection; Exercise Test; Exercise Therapy; Exercise Tolerance; Heart; Heart Failure; Heart Ventricles; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Stroke Volume; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left; Ventricular Function, Left

Although the accurate detection of ischemic etiology is important in the management of patients with severe left ventricular (LV) dysfunction, it is difficult to determine using a non-invasive strategy. The present study investigates whether perfusion and regional functional abnormalities identified by quantitative electrocardiographic gated single-photon emission computed tomography (QGS) at rest can detect ischemic LV dysfunction in patients with severe LV dysfunction.. Rest QGS with (99m)Tc-tetrofosmin was performed on 54 consecutive patients with LV ejection fraction of

Topics: Adult; Aged; Aged, 80 and over; Clinical Protocols; Coronary Circulation; Electrocardiography; Female; Gated Blood-Pool Imaging; Humans; Male; Middle Aged; Movement; Myocardial Contraction; Myocardial Ischemia; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; ROC Curve; Stroke Volume; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

Although preserved glucose metabolism is considered to be a marker of myocardial viability in the chronic stage, it has not been fully elucidated whether this is also true with regard to reperfused acute myocardial infarction (AMI). The aim of this study was to compare the diagnostic performance of(99m)Tc-tetrofosmin SPECT and(18)F-fluorodeoxyglucose (FDG) PET for the prediction of functional recovery in reperfused AMI.. The study population comprised 28 patients. Both tetrofosmin SPECT and FDG PET were performed in all 28 patients at ca. 2 weeks and in 23 at 6 months. The tetrofosmin and FDG findings in infarct-related segments were compared with the regional wall motion score assessed by left ventriculography over 6 months to determine the predictive value for functional recovery.. Of 120 infarct-related segments, 83 had preserved flow (tetrofosmin uptake >/=50%) and 81 had preserved glucose metabolism (FDG uptake >/=40%). The sensitivity and specificity of tetrofosmin SPECT for the prediction of functional recovery tended to be superior to those of FDG PET (90.0% and 72.5% vs 85.0% and 67.5%, respectively). Thirteen segments with preserved flow and decreased glucose metabolism demonstrated marked recovery of contractile function from 2.5+/-1.0 to 1.4+/-1.4 (p<0.01), with restoration of glucose metabolism at 6 months. In contrast, 11 segments with decreased flow and preserved glucose metabolism demonstrated incomplete functional improvement from 3.0+/-0.8 to 2.2+/-1.2.. In the subacute phase, preserved myocardial blood flow is more reliable than glucose metabolism in predicting functional recovery in reperfused myocardium.

Topics: Aged; Aged, 80 and over; Female; Fluorodeoxyglucose F18; Humans; Male; Middle Aged; Myocardial Infarction; Myocardial Reperfusion; Organophosphorus Compounds; Organotechnetium Compounds; Positron-Emission Tomography; Prognosis; Radiopharmaceuticals; Recovery of Function; Reproducibility of Results; Sensitivity and Specificity; Tomography, Emission-Computed, Single-Photon; Treatment Outcome; Ventricular Dysfunction, Left

Precise and reliable assessment of left ventricular (LV) function and dimensions is prognostically important in cardiac patients. As the integration of SPECT and multislice CT into hybrid scanners will promote the combined use of both techniques in the same patient, a comparison of the 2 methods is pertinent. We aimed at comparing LV dimensions, muscle mass, and function obtained by electrocardiographically gated 64-slice CT versus gated-SPECT.. Sixty patients (mean age, 64 +/- 8 y) referred for evaluation of coronary artery disease underwent 99mTc-tetrofosmin gated SPECT and 64-slice CT within 4 +/- 2 d. LV ejection fraction (LVEF), end-systolic volume (ESV), and end-diastolic volume (EDV) from CT were compared with SPECT. Additionally, LV muscle mass and quantitative regional wall motion were assessed in 20 patients with both methods.. CT was in good agreement with SPECT for quantification of LVEF (r = 0.825), EDV (r = 0.898), and ESV (r = 0.956; all P < 0.0001). LVEF was 59% +/- 13% measured by SPECT and slightly higher but not significantly different by CT (60% +/- 12%; mean difference compared with SPECT, 1.1% +/- 1.7%; P = not significant). A systematic overestimation using CT for EDV (147 +/- 60 mL vs. 113 +/- 52 mL; mean difference, 33.5 +/- 23.1 mL) and ESV (63 +/- 55 mL vs. 53 +/- 49 mL; mean difference, 9.3 +/- 15.9 mL; P < 0.0001) was found compared with SPECT. A good correlation for muscle mass was found between the 2 methods (r = 0.868; P < 0.005). However, muscle mass calculated by SPECT was significantly lower compared with CT (127 +/- 24 g vs. 148 +/- 37 g; mean difference, 23.0 +/- 12.2 g; P < 0.001). The correlation for regional wall motion between the 2 methods was moderate (r = 0.648; P < 0.0001).. LVEF and LV functional parameters as determined by 64-slice CT agree over a wide range of clinically relevant values with gated SPECT. However, interchangeable use of the 2 techniques should be avoided for LV volumes, muscle mass, and regional wall motion because of variances inherent to the different techniques.

Topics: Adult; Aged; Aged, 80 and over; Electrocardiography; Female; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed; Ventricular Dysfunction, Left; Ventricular Function, Left

Myocardial perfusion SPECT is frequently affected by artefacts related to abdominal activity. Metoclopramide has been suggested to relieve this, but two previous studies have shown conflicting results.. Ninety-five patients received 10 mg metoclopramide orally after injection of 99mTc-tetrofosmin for the stress scan and 86 patients had metoclopramide after their rest injection. A control group of 82 patients did not receive metoclopramide. Scans were evaluated visually by three readers.. Metoclopramide given before the stress scan led to abdominal activity being visually better in 16 scans, worse in 10, and unchanged in 67 scans, compared to the same patient's rest scan without metoclopramide administration. Metoclopramide administered before the rest scan resulted in abdominal activity in 11 scans being visually better, in 19 worse, and 53 scans were deemed unchanged. These differences were not significant. The number of repeat stress or rest scans was not significantly different between patients who had received metoclopramide and those who had not. The administration of metoclopramide, irrespective of whether it was given before the stress or rest scan, made no significant difference to inferior wall-to-abdomen count ratio.. Neither qualitative nor quantitative analysis showed an effect of metoclopramide on abdominal activity in myocardial perfusion SPECT.

Topics: Abdomen; Adenosine; Administration, Oral; Aged; Antiemetics; Artifacts; Exercise Test; Female; Humans; Image Enhancement; Male; Metoclopramide; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Rest; Sensitivity and Specificity; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

This study was carried out to assess the repeatability of left ventricular ejection fraction (EF) and volume values obtained using Cedars-Sinai quantitative gated single photon emission computed tomography (SPECT) (QGS) software and relatively low doses of 400-600 MBq of 99mTc-tetrofosmin.. Repeatability was assessed in a group of 75 patients, with both normal and reduced EF, who underwent repeat 99mTc-tetrofosmin gated SPECT studies and showed no clinical change in cardiac status. Gated SPECT data were acquired 1 h after injection at rest of 400-600 MBq of 99mTc-tetrofosmin. The standard patient dose was 400 MBq; however, some patients with a weight of >90 kg were given increased doses up to a maximum of 600 MBq.. There was good correlation of EF and volumes between the first and repeat measurements, and no significant difference between the mean EF and volumes for both the initial and repeat measurements. Background-corrected counts in the left ventricle were calculated and patients were divided into two groups: one with low counts and one with high counts. The mean difference in EF between the first and repeat measurements was significantly higher for patients in the low count group compared with those in the high count group, but there was no significant change in volume. Similarly, the mean sequential difference in EF was significantly higher for patients with normal EF, but there was no significant difference in volume.. We have demonstrated that EF measured using 99mTc-tetrofosmin gated SPECT is repeatable, particularly for patients with low EF, provided that adequate left ventricular counts are obtained. This will require doses greater than 400 MBq in larger patients. Ventricular volumes calculated using QGS may not be sufficiently repeatable for clinical use.

Topics: Algorithms; Female; Humans; Image Interpretation, Computer-Assisted; Male; Middle Aged; Myocardial Infarction; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Software Validation; Stroke Volume; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

The clinical usefulness of characterizing reperfused myocardium by perfusion/thickening assessment using electrocardiographic gated single photon emission computed tomography (SPECT) has not been investigated. We evaluated whether single-injection gated SPECT with 99mTc tetrofosmin early after primary percutaneous coronary intervention (PCI) can predict left ventricular (LV) functional recovery.. Gated SPECT was performed 3 days after primary PCI in 45 patients with acute myocardial infarction and revascularized segments were classified into perfusion/thickening mismatched segments, matched normal and matched abnormal segments. Gated SPECT was repeated 3 months later to evaluate the changes in LV ejection fraction (deltaLVEF).. Among 332 revascularized segments, there were 83 mismatched segments, 163 matched abnormal segments and 86 matched normal segments. In all the patients, LVEF increased significantly from 3 days to 3 months after primary PCI (52+/-13 to 57+/-14%, P<0.0001). Patients were divided into two groups according to deltaLVEF: 24 patients with LV functional recovery (deltaLVEF > or = 5%) and 21 patients without LV functional recovery. The number of mismatched segments in patients with LV functional recovery was significantly greater than that in patients without (2.7+/-1.7 vs. 0.8+/-1.4, P<0.0003) despite no differences in the number of matched abnormal and matched normal segments. There was a significant correlation between deltaLVEF and the number of mismatched segments (r=0.56, P<0.0001) and LVEF at 3 months after primary PCI was related to the number of matched abnormal segments (r=-0.78, P<0.0001).. Single-injection gated SPECT early after primary PCI can predict LV functional recovery.

Topics: Angioplasty, Balloon, Coronary; Female; Gated Blood-Pool Imaging; Humans; Male; Middle Aged; Myocardial Infarction; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Radiopharmaceuticals; Recovery of Function; Reproducibility of Results; Sensitivity and Specificity; Severity of Illness Index; Stroke Volume; Treatment Outcome; Ventricular Dysfunction, Left

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

The aim of this study was to compare (99m)Tc-tetrofosmin SPECT with contrast-enhanced MRI (ceMRI), a new direct sign of myocardial fibrosis.. We studied 21 patients (age, 60 +/- 11 y; 19 male) with previous myocardial infarction and severe left ventricular dysfunction (ceMRI EF, 29% +/- 6%). All patients underwent resting and postnitrate (intravenous isosorbide dinitrate) (99m)Tc-tetrofosmin gated SPECT as well as ceMRI. Scintigraphic analysis was performed using quantitative perfusion SPECT (QPS), providing the percentage radiotracer uptake and defect severity in a 20-segment model. Hyperenhancement was defined by the increase of ceMRI signal intensity 20 min after intravenous injection of gadolinium-diethylenetriaminepentaacetic acid and its regional extension as the percentage of the total segment area.. In ceMRI dysfunctional segments, the correlation between the extent of hyperenhancement and both (99m)Tc-tetrofosmin uptake and defect severity was significantly better after nitrate administration rather than at rest (P < 0.0001). Using a ceMRI cutoff below 40%, 102 of 196 (52%) segments were viable, whereas 94 (48%) segments were not viable. According to receiver-operating characteristic curve analysis, diagnostic accuracies were higher for postnitrate (99m)Tc-tetrofosmin uptake as well as perfusion defect severity than using resting data (0.84 vs. 0.71, P < 0.001; 0.89 vs. 0.76, P < 0.001, respectively).. After nitrate administration, (99m)Tc-tetrofosmin uptake and perfusion defect severity were closely related to ceMRI, demonstrating, in vivo, the existence of an inverse correlation between the transmural distribution of fibrosis and tracer delivery to the myocardium.

Topics: Adult; Aged; Aged, 80 and over; Contrast Media; Exercise Test; Female; Gadolinium DTPA; Heart; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Myocardial Infarction; Myocardium; Nitrates; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Severity of Illness Index; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

To compare the currently available gated SPECT software programs, quantitative gated SPECT (QGS), Emory Cardiac Toolbox (ECTb), Left Ventricular Global Thickening Fraction (LVGTF), and the recently developed Layer of Maximum Count (LMC) method with equilibrium Gated Blood Pool (GBP) scintigraphy in calculating the ejection fraction in patients with small hearts.. Twenty patients with small hearts (end diastolic volume <85 ml) were collected for the study. Gated myocardial perfusion SPECT and planar GBP were performed for all patients. The four methods QGS, ECTb, and LVGTF and LMC were used for volumes estimation and ejection fraction calculation.. ANOVA analysis revealed significant differences among the methods in ejection fraction estimation (P<0.0001). The mean ejection fraction by GBP was significantly overestimated by QGS and ECTb and LVGTF (P<0.0001, P<0.0001 and P=0.006, respectively). The mean ejection fraction by GBP was not significantly different from that by the LMC method (P=0.213). Ejection fraction measurements by QGS and ECTb yielded moderate correlation with GBP values (r=0.588, P=0.006; and r=0.564, P=0.010, respectively). The ejection fraction by the LMC method was marginally correlated but LVGTF showed a non-significant correlation with GBP (r=0.438, P=0.053; and r=0.155, P=0.515, respectively). Agreement analysis for ejection fraction estimation by QGS and ECTb demonstrated a non-significant correlation between the difference and the mean. The LMC method showed a non-significant trend to decrease the difference with GBP as the mean increased. However, the LVGTF method significantly increased the difference as the mean increased.. The currently available gated SPECT methods have moderate to poor correlations in addition to wide agreement limits with gated blood pool studies in patients with small hearts. Improvement of these methods to achieve better results in such patients is recommended. The newly developed LMC method yielded better results in the group with small hearts but with low interchangeability with GBP studies.

Topics: Female; Gated Blood-Pool Imaging; Heart Defects, Congenital; Humans; Image Interpretation, Computer-Assisted; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Stroke Volume; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

We compared Takotsubo cardiomyopathy (transient left ventricular apical ballooning) with acute myocardial infarction (AMI) using two-dimensional echocardiography, 99mTc-tetrofosmin, 99mTc-PYP, 123I-BMIPP and 123I-MIBG myocardial SPECT.. We examined 7 patients with Takotsubo cardiomyopathy and 7 with AMI at the time of emergency admission (acute phase), and 2-14 days (subacute phase), one month (chronic phase), and 3 months (chronic II phase) after the attack. The left ventricle was divided into nine regions on echocardiograms and SPECT images, and the degree of abnormalities in each region was scored according to five grades from normal (0) to severely abnormal (4).. Coronary angiography showed the absence of stenotic regions in patients with Takotsubo cardiomyopathy, and severely stenotic and/or occlusive lesions in patients with AMI. The total ST segment elevation on electrocardiograms (mm) was 7.8 +/- 3.7 in those with Takotsubo cardiomyopathy, and 7.3 +/- 3.9 in patients with AMI. Abnormal wall motion scores on echocardiograms were 14.2 +/- 4.6, 4.7 +/- 4.0, 1.7 +/- 2.0 and 0.5 +/- 0.4 during the acute, subacute, chronic and chronic II phases, respectively, in patients with Takotsubo cardiomyopathy, and 14.0 +/- 4.3, 11.4 +/- 3.9, 8.8 +/- 3.6 and 5.2 +/- 4.8 in those with AMI. Abnormal myocardial perfusion scores on 99mTc-tetrofosmin images were 11.8 +/- 3.5, 3.2 +/- 3.0, 0.5 +/- 1.2 and 0.2 +/- 0.4 during the acute, subacute, chronic and chronic II phases, in patients with Takotsubo cardiomyopathy, and 16.2 +/- 4.3, 13.9 +/- 4.6, 7.9 +/- 4.6 and 5.0 +/- 4.5, respectively, in those with AMI. Abnormal myocardial fatty acid scores on 123I-BMIPP images were 12.6 +/- 3.7, 6.8 +/- 3.2 and 0.4 +/- 0.6 during the subacute, chronic and chronic II phases, respectively, in patients with Takotsubo cardiomyopathy, and 16.5 +/- 5.1, 14.7 +/- 4.8 and 7.5 +/- 4.5 in those with AMI. Abnormal myocardial sympathetic nerve function scores on 123I-MIBG images were 14.8 +/- 4.0, 8.8 +/- 4.0 and 0.4 +/- 0.6 during the subacute, chronic, chronic II phases, respectively, in patients with Takotsubo cardiomyopathy, and 18.6 +/- 6.5, 16.8 +/- 6.8 and 12.9 +/- 5.2 in those with AMI. Myocardial 99mTc-PYP uptake was abnormal not only in patients with AMI but also in those with Takotsubo cardiomyopathy during the acute phase.. Takotsubo cardiomyopathy might represent a stunned myocardium caused by a disturbance of the coronary microcirculation.

Topics: 3-Iodobenzylguanidine; Aged; Aged, 80 and over; Cardiomyopathies; Diagnosis, Differential; Fatty Acids; Female; Humans; Iodobenzenes; Male; Middle Aged; Myocardial Infarction; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Syndrome; Technetium Tc 99m Pyrophosphate; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

The accuracy of viability and defect size detection by Tc-tetrofosmin has been discussed by several authors. The lower myocardial extraction fraction of the latter compared with Tc-sestamibi or Tl has often been emphasized. We hypothesized that the intracoronary (i.c.) injection of tracer activity, i.e. higher than that theoretically achievable in the case of intravenous (i.v.) administration, could demonstrate the clinical relevance of this finding intra-individually. In this study, myocardial perfusion images obtained after tracer injection down the infarct-related artery were compared with i.v. injection images in the same patients. The trial also provided us with the opportunity to compare the wall motion values calculated using conventional Tc-tetrofosmin gated single-photon emission computed tomography (SPECT) studies with those obtained using optimal target/background ratios after i.c. injection.. Fourteen patients with acute myocardial infarction, no history of previous cardiac events, single vessel disease and no visible collaterals in the coronary arteriogram were included in the study. Electrocardiogram gated SPECT was carried out separately after i.c. and i.v. injections of the tracer within 5-7 days following thrombolytic therapy. Myocardial perfusion patterns were compared by contingency table analysis after semi-quantitative visual scoring. Segmental wall motion was compared using quantified polar map data in a subset of patients (eight of 14) with normal to moderately hypoperfused myocardium supplied by the left coronary artery.. Visual perfusion scores of both studies showed good concordance (kappa, 0.70), with complete agreement in 94 of 119 segments. Nearly all of the discordant segments (24 of 25) were mildly better scored in i.c. studies than in i.v. studies. The mean wall motion values calculated on polar maps of 78 segments for i.c. and i.v. studies were 8.4 +/- 1.2 mm and 8.2 +/- 1.3 mm (mean Delta wall motion=0.23 mm), respectively. High segmental wall motion correlation was observed (R=0.90; P<0.0001).. It can be concluded that infarct-related myocardial perfusion scores obtained after i.c. and i.v. injections of Tc-tetrofosmin compare favourably, with a total agreement rate of 79%. However, the additional information obtained in 21% of the total number of myocardial segments by i.c. injection may indicate a mild underestimation of myocardial viability by i.v. injection. Conventional gated SPECT using i.v. Tc-tetrofosmin was demonstrated to be a reliable technique in the detection of true wall motion.

Topics: Arteries; Coronary Vessels; Female; Humans; Injections, Intra-Arterial; Injections, Intravenous; Male; Middle Aged; Movement; Myocardial Infarction; Organophosphorus Compounds; Organotechnetium Compounds; Radionuclide Imaging; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Ventricular Dysfunction, Left

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

This study evaluated the ability of low-dose dobutamine stress 99mTc tetrofosmin (DSTF) quantitative gated single photon emission computed tomography (QGS) performed during the acute phase of myocardial infarction to predict subsequent myocardial viability and detect stunned myocardium. Twenty-four patients suffering their first acute myocardial infarction (AMI) underwent coronary angioplasty after coronary angiography (CAG) immediately following admission. Follow-up CAG and left ventriculography (LVG) were performed 10 days and 6 months later. All patients underwent DSTF QGS to measure left ventricular ejection fraction (LVEF) at rest and during dobutamine infusion (10 microg.kg(-1).min(-1)) 14 days after angioplasty. No patient suffered coronary restenosis. After 6 months, the LVEF measured by LVG improved >5% in 12 patients (group A), and did not improve in the remaining 12 patients (group B). The culprit coronary artery, the peak serum creatine phosphokinase concentration, the recanalization time, and the LVEF during the acute phase were similar in the two groups. However, the increase in the LVEF was greater in group A than in group B during dobutamine infusion (deltaLVEF) as measured by DSTF QGS (11.2+/-3.8% vs 2.9+/-4.7%, P <0.001). If a cut-off value of 6.5% for the deltaLVEF was used to predict the improvement in LVEF during the chronic phase, then the sensitivity of this test was 83.3% and its specificity was 83.3%. It is concluded that DSTF QGS during AMI can be used to predict myocardial viability and detect stunned myocardium.

Topics: Acute Disease; Aged; Aged, 80 and over; Dobutamine; Female; Follow-Up Studies; Gated Blood-Pool Imaging; Heart Ventricles; Humans; Male; Middle Aged; Myocardial Infarction; Myocardial Stunning; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Stress, Physiological; Stroke Volume; Tissue Survival; Ventricular Dysfunction, Left

Because of damage to cardiomyocytes and the contractile apparatus, contractile reserve may be observed less frequently in hibernating than in stunned myocardium. The aim of this study was to assess the presence of contractile reserve in response to dobutamine infusion in a large group of patients with stunned and hibernating myocardium.. A total of 198 consecutive patients with ischemic cardiomyopathy (left ventricular ejection fraction < or = 40%) underwent resting 2-dimensional echocardiography to assess regional contractile dysfunction. On the basis of assessment of perfusion (with (99m)Tc-tetrofosmin SPECT) and glucose use (with (18)F-FDG SPECT), dysfunctional segments were grouped. Dysfunctional segments with normal perfusion were classified as stunned. Dysfunctional segments with a perfusion defect were classified as hibernating when a perfusion-(18)F-FDG mismatch was present. Dysfunctional segments with a perfusion defect were classified as scar tissue when a perfusion-(18)F-FDG match was present; these segments were subdivided into nontransmural and transmural scars. Contractile reserve was evaluated by dobutamine stress echocardiography.. Dobutamine-induced contractile reserve was more frequently found in stunned than in hibernating myocardium (61% vs. 51%, respectively; P < 0.01). Only 14% of the scarred segments improved in wall motion during dobutamine infusion, significantly less than stunned or hibernating myocardium (P < 0.001). Nontransmural scars exhibited contractile reserve more frequently than did transmural scars.. The progressive reduction of contractile reserve in stunned, hibernating, and scarred myocardium supports the hypothesis that stunning, hibernation, and scarring are not circumscript pathophysiologic entities but represent gradual ultrastructural damage on the myocyte level.

Topics: Dobutamine; Echocardiography; Female; Fluorodeoxyglucose F18; Heart; Humans; Male; Middle Aged; Myocardial Contraction; Myocardial Infarction; Myocardial Ischemia; Myocardial Stunning; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Single-Blind Method; Stress, Physiological; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

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

Angiographic Thrombolysis in Myocardial Infarction (TIMI) flow grade

Topics: Angioplasty, Balloon, Coronary; Coronary Angiography; Female; Humans; Male; Middle Aged; Myocardial Infarction; Myocardial Reperfusion Injury; Organophosphorus Compounds; Organotechnetium Compounds; Radionuclide Imaging; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Ventricular Dysfunction, Left

Factors affecting the accuracy of left ventricular ejection fraction (LVEF) quantification using automated quantitative gated SPECT have not been adequately investigated in patients in the clinical setting. Therefore, the authors studied the effect of defect size and Tc-99m tetrofosmin dose on the accuracy of LVEF calculation using the automated QGS program.. Thirty-two consecutive patients underwent gated rest and stress myocardial perfusion SPECT after administration of 8 and 27 mCi Tc-99m tetrofosmin, respectively. The LVEF was obtained for both the rest and stress studies using the QGS program and compared with the LVEF obtained using quantitative echocardiography performed within 2 weeks. Myocardial perfusion defects were recorded as scarring, ischemia, or mixed scarring and ischemia in 12 left ventricular segments. The defect size was evaluated by adding the number of affected segments.. The mean LVEF calculated using high-dose stress QGS, low-dose rest QGS, and echocardiography was 49.2% +/- 15%, 46.2% +/- 17% and 48.7% +/- 16.9% respectively, with no statistically significant differences. The LVEF obtained using high-dose stress QGS correlated better with echocardiography than did that obtained using low-dose rest QGS (r = 0.86 versus 0.76). In addition, when the high-dose stress LVEF in the 14 patients with normal myocardial perfusion was compared with that in 11 patients who had one- or two-segment perfusion defects, and 7 patients who had perfusion defects in > or = three segments, there was good correlation with echocardiography in the three patient groups (r = 0.85, 0.88, and 0.91, respectively).. Myocardial perfusion defects do not affect the accuracy of LVEF calculation using automated QGS. High-dose gated myocardial SPECT demonstrated better correlation with quantitative echocardiography LVEF results.

Topics: Adult; Aged; Dipyridamole; Dose-Response Relationship, Drug; Female; Gated Blood-Pool Imaging; Heart Diseases; Humans; Image Interpretation, Computer-Assisted; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Reproducibility of Results; Sensitivity and Specificity; Statistics as Topic; Stress, Physiological; Stroke Volume; Ultrasonography; Ventricular Dysfunction, Left

Assessment of ventricular function is an important diagnostic and prognostic tool in coronary heart disease (CHD). The objective of this study was to compare radionuclide ventriculography (RVG), echocardiography (ECHO) and gated planar tetrofosmin myocardial scintigraphy (GPTF) in patients with CHD. Radionuclide ventriculography in left anterior oblique (LAO) and left lateral (LLT) projections was performed in 44 patients. Two days later, rest tetrofosmin perfusion tomoscintigraphy (SPECT) and rest GPTF in RVG identical parameters and projections were acquired. Within the two following days, the patients underwent two-dimensional ECHO. GPTF studies were processed and interpreted in original (NI-GPTF) and image inverted, RVG like form (I-GPTF). All visual interpretations were evaluated with a semi-quantitative scoring system. Quantitative analysis was performed on parametric images by means of segmental regions of interest. Linear regression and contingency analysis were carried out in overall analysis and on a segmental basis separately by accepting the RVG as the standard for the whole investigation. In overall cine-mode evaluation, NI-GPTF (r = 0.77, p < 0.001, complete agreement (CA) = 84%) was superior to I-GPTF (r = 0.73, p < 0.001, CA = 82%) and ECHO (r = 0.39, p < 0.001, CA = 78%), compared to RVG. On a segmental basis, NI-GPTF showed the best RVG-correlations except for inferoapical, mid-inferior, mid-anterior and anterobasal segments. In visual analysis of functional images, the best RVG-agreement was observed in I-GPTF (r = 0.72, p < 0.001, CA = 77%). On a segmental basis, I-GPTF showed the best RVG-correlations except for posterolateral, mid-inferior, mid-anterior and anterobasal segments. In overall quantitative evaluation, amplitude values in both I-GPTF (r = 0.76, p < 0.001) and NI-GPTF (r = 0.75, p < 0.001) studies were well correlated with RVG amplitude. I-GPTF gave the best RVG-correlation of phase (r = 0.59, p < 0.001). The mean phase and standard deviation RVG-correlations of I-GPTF were r = 0.92, p < 0.001 and r = 0.53, p < 0.001 respectively. In segmental quantification, amplitude values of all segments in I-GPTF were better RVG-correlated than in NI-GPTF. In conclusion, GPTF could be a time saving alternative to ECHO in the evaluation of wall motion by the nuclear medicine physician. Because of differing segmental RVG correlations, NI-GPTF and I-GPTF should be both interpreted to improve the diagnostic value of the method. Cine-mode

Topics: Female; Gated Blood-Pool Imaging; Humans; Male; Middle Aged; Myocardial Contraction; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Statistics as Topic; Ultrasonography; Ventricular Dysfunction, Left

Left ventricular mass is an important determinant of diagnosis and prognosis in patients with heart disease. The aim of the present study was to validate measurement of the left ventricular mass index (LVMI) by quantitative gated myocardial SPECT (QGS) with 99mTc-tetrofosmin by comparing it with echocardiography.. QGS and M-mode echocardiography (Echo) were performed within one month of each other in 179 patients. M-mode echocardiography was carried out according to Devereux's method. QGS images were acquired one hour after injection of 99Tc-tetrofosmin at rest. Myocardial volume was defined as the volume between the endocardial and epicardial surface in the end-diastolic phase. LVMI (g/m2) was defined as myocardial volume divided by myocardial specific density and corrected for body surface area. QGS LVMI measurements were performed twice by the same observer and independently by two different observers. Regional hypoperfusion in the group of patients with old myocardial infarction (n = 26) was evaluated semiquantitatively on the basis of the total defect score on the resting 99mTc-tetrofosmin SPECT images.. Among the patients as a whole QGS LVMI was significantly correlated with Echo LVMI (r = 0.96, p < 0.001). Intra-observer and inter-observer analyses showed significant reproducibility (r = 0.99 and r = 0.98, respectively, p < 0.001). In the patients with old myocardial infarction, but QGS LVMI was significantly lower than Echo LVMI (p < 0.001), and the magnitude of the underestimation was closely related to the severity of the perfusion defect on the resting SPECT images.. Measurements of LVMI by 99mTc-tetrofosmin QGS are reproducible and consistent with echocardiograpic estimates. Underestimation in patients with severe perfusion defects must be taken into consideration.

Topics: Echocardiography; Feasibility Studies; Female; Gated Blood-Pool Imaging; Heart Diseases; Heart Ventricles; Humans; Male; Middle Aged; Observer Variation; Organ Size; Organophosphorus Compounds; Organotechnetium Compounds; Radiography; Radiopharmaceuticals; Sensitivity and Specificity; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

The diagnostic value of technetium-99m tetrofosmin (TF) washout in hypertrophic cardiomyopathy (HCM) was examined by investigating its relation to the metabolic abnormality depicted by iodine-123 beta-methyl- p-iodophenylpentadecanoic acid (BMIPP) uptake and the left ventricular (LV) myocardial wall thickness as measured by magnetic resonance imaging (MRI). TF washout was evaluated in 31 patients with HCM and 23 normal control subjects using 30-min (early) and 3-h (delayed) TF single-photon emission tomography images. The LV myocardial wall was divided into 19 segments and the percentage TF washout, regional BMIPP uptake and LV wall thickness were measured in each segment. Mean TF washout in the patients with HCM was significantly faster than that in normal control subjects (23.7+/-5.7 vs 13.4+/-4.1, P<0.0001). In the patients with HCM, TF washout showed an excellent correlation with MRI wall thickness ( r=0.82, P<0.0001) and a good inverse correlation with regional BMIPP uptake ( r=-0.72, P<0.0001). In addition, a good linear correlation was observed between TF uptake and MRI wall thickness in the 19 regional segments. In conclusion, the degree of TF washout corresponds well with the severity of myocardial wall thickness and the degree of metabolic abnormality in patients with HCM. These results suggest that enhanced TF washout might provide additional clinical information regarding metabolic alterations in HCM.

Topics: Adult; Cardiomyopathy, Hypertrophic; Fatty Acids; Heart Ventricles; Humans; Iodobenzenes; Magnetic Resonance Imaging; Male; Metabolic Clearance Rate; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radionuclide Imaging; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Statistics as Topic; 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

We assessed Takotsubo (ampulla) cardiomyopathy compared with acute coronary syndrome (ACS) using two-dimensional echocardiography and 99mTc-tetrofosmin myocardial SPECT.. We examined 10 patients with Takotsubo cardiomyopathy and 16 with ACS at the time of emergency admission (acute phase), at three to nine days after the attack (subacute phase) and at one month after the attack (chronic phase). The left ventricle was divided into nine regions on echocardiograms and SPECT images, and the degree of abnormalities in each region was scored in five grades from normal (0) to severely abnormal (4).. Coronary angiography revealed total or subtotal occlusion in patients with ACS but no stenotic legions in those with Takotsubo cardiomyopathy. The amount of ST segment elevation (mm) was 7.9 +/- 3.4 in patients with Takotsubo cardiomyopathy and 7.3 +/- 3.7 in those with ACS (N.S.). Abnormal wall motion scores on echocardiograms were 13.8 +/- 4.4, 4.4 +/- 3.8 and 1.8 +/- 2.3 during the acute, subacute and chronic phases in patients with Takotsubo cardiomyopathy, and 13.9 +/- 4.0, 11.7 +/- 3.7, 7.6 +/- 4.2, respectively in patients with ACS. The value of MB fraction of creatine phosphokinase (IU/l) was 34 +/- 23 in patients with Takotsubo cardiomyopathy and 326 +/- 98 in those with ACS (p < 0.001). Abnormal myocardial perfusion scores on 99mTc-tetrofosmin myocardial SPECT were 11.4 +/- 3.2, 3.2 +/- 3.3 and 0.7 +/- 1.1 during the acute, subacute and chronic phases respectively, in patients with Takotsubo cardiomyopathy, and 15.8 +/- 4.1, 13.5 +/- 4.4, 8.2 +/- 4.4, respectively, in those with ACS. The numbers of myocardial segments that did not uptake 99mTc-tetrofosmin during the acute phase were 0.5 +/- 0.8 and 3.6 +/- 2.8 in patients with Takotsubo cardiomyopathy and ACS, respectively.. Impaired coronary microcirculation might be a causative mechanism of Takotsubo cardiomyopathy.

Topics: Acute Disease; Aged; Aged, 80 and over; Cardiomyopathies; Coronary Disease; Diagnosis, Differential; Female; Heart Ventricles; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Syndrome; Tomography, Emission-Computed, Single-Photon; 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

The purpose of this study was to address the issue of 180 degrees versus 360 degrees data collection for left ventricular ejection fraction (LVEF) and left ventricular volume measurements using gated myocardial perfusion tomography (gMPT) and gated blood pool tomography (gBPT). Thirty patients with known coronary artery disease were injected in a random sequence with 925 MBq of technetium-99m tetrofosmin and, within 2 days, with 740 MBq of (99m)Tc-labelled human serum albumin. gMPT and gBPT were acquired using 360 degrees data collection and reconstructed by filtered backprojection using all the acquired projection images and separately using only projection images acquired from 45 degrees LPO to 45 degrees RAO. In order to have the same global count densities, the counts in the 360 degrees data set were redistributed using binomial deviates just before reconstruction. After reorientation along the left ventricular long axis, LVEF and left ventricular volumes were calculated using fully automatic algorithms. Twenty-eight patients also underwent planar radionuclide angiocardiography (PRNA) on the same day as the gBPT. For the gMPT studies, the correlation between 180 degrees data collection and 360 degrees data collection was excellent ( r>0.98). Bland-Altman analysis revealed small systematic and random differences (<6%) between 180 degrees and 360 degrees. For the gBPT studies, the correlation between 180 degrees data collection and 360 degrees data collection was very good ( r>0.93). However, Bland-Altman analysis revealed systematic differences of 26% and random differences of 17%. When PRNA was used as a reference, the best results were obtained with gMPT acquired using 180 degrees data, while the worst results were obtained with gBPT acquired using 180 degrees data. In conclusion, when evaluating LVEF and left ventricular volumes from gMPT, either 180 degrees or 360 degrees orbits can be used. However, 360 degrees data acquisition is recommended when evaluating LVEF and left ventricular volumes from gBPT.

Topics: Aged; Aged, 80 and over; Female; Gated Blood-Pool Imaging; Humans; Image Interpretation, Computer-Assisted; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Statistics as Topic; Stroke Volume; Technetium Tc 99m Aggregated Albumin; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

The effect of adenosine and exercise on gated SPET left ventricular ejection fraction (LVEF), end diastolic volume (EDV) and end systolic volume (ESV) has not been fully investigated. The aim of the study was to compare functional measurements obtained in one-day adenosine rest and two-day stress-rest protocols in relation to ischaemia.. Out of 226 consecutive patients examined with submaximal treadmill stress-rest 700 MBq Tc-99m MIBI, 26 were chosen to match those subjected to adenosine (140 micro g/kg/min) enhanced by a low level exercise protocol (300 MBq and 700 MBq Tc-99m tetrofosmin for stress and rest respectively). All images were acquired on a double head system and were gated using 8 frames, 25 s per frame.. ED and ES volumes increased after adenosine but decreased after treadmill resulting in the post-stress LVEF being significantly greater than after adenosine, 60 +/- 11 v. 51 +/- 13% (p < 0.01). This was caused by the smaller post-stress ESV in the treadmill group 40 +/- 20 v. 51 +/- 34, p < 0.05. In non-ischaemic scans the LVEF was greater (61 +/- 8 v. 51 +/- 14, p < 0.01) and EDV and ESV smaller after both stress and rest.. The adenosine test may have an opposite influence on the EDV and ESV in comparison to the submaximal treadmill test and therefore the left ventricular function measurements after adenosine infusion should be interpreted carefully and may not represent those acquired after physical exercise. In the gated SPET scans showing ischaemia the post-stress EDV and ESV may be greater and the LVEF lower than at rest.

Topics: Adenosine; Aged; Exercise Test; Female; Gated Blood-Pool Imaging; Humans; Male; Middle Aged; Myocardial Ischemia; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Technetium Tc 99m Sestamibi; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

To investigate myocardial fatty acid metabolism and its relationship with left ventricular (LV) function and perfusion in hypertrophic cardiomyopathy (HCM) and dilated cardiomyopathy (DCM).. Thirty-nine patients with cardiomyopathies (58 +/- 14 y), comprising 15 DCM and 24 HCM, and 9 age-matched healthy controls were studied with 123I-15-(p-iodophenyl)-3-(R,S)-methylpentadecanoic acid (BMIPP) and 99mTc-tetrofosmin (TF) electrocardiographically gated SPECT. As parameters of myocardial fatty acid metabolism, the heart-to-mediastinum ratio (H/M) and global washout of BMIPP were calculated from early and delayed planar images, while regional BMIPP uptake and washout were calculated from SPECT. In TF study, the H/M (H/M-TF) and LV ejection fraction (LVEF) were calculated as global parameters of perfusion and function, while regional TF uptake and wall thickening index were calculated as regional parameters of perfusion and function using the Quantitative Gated SPECT software. The differences in the parameters and the correlations between the parameters from the 2 studies were investigated by one-way ANOVA and multiple linear regression analysis.. BMIPP uptake was decreased (p < 0.05), and its washout was increased (p < 0.05) in DCM and HCM. In multiple linear regression analysis, global BMIPP parameters showed no significant correlation with LVEF (p > 0.05), but showed a significant correlation with H/M-TF (p < 0.05) in DCM and HCM. According to the partial correlation coefficient, early H/M was the only significant factor (p < 0.05) for predicting H/M-TF in DCM and HCM. Multiple linear regression analysis on regional parameters showed regional BMIPP parameters had no correlation with regional function (p > 0.05) but had a significant correlation with regional perfusion (p < 0.0001) in DCM. In HCM, regional BMIPP parameters showed significant multiple linear correlations with both regional function (p < 0.005) and perfusion (p < 0.0001). According to the partial correlation coefficients, delayed regional BMIPP uptake was the most significant factor for predicting regional function in HCM, while early regional BMIPP uptake was the only or the most significant factor for predicting regional perfusion in DCM and HCM, respectively.. In DCM, BMIPP uptake and washout could not reflect LV function. In HCM, regional delayed BMIPP uptake might be useful for evaluating regional function. In DCM and HCM, early BMIPP uptake might be largely determined by myocardial perfusion.

Topics: Adolescent; Adult; Aged; Cardiomyopathy, Dilated; Cardiomyopathy, Hypertrophic; Electrocardiography; Fatty Acids; Female; Gated Blood-Pool Imaging; Heart Ventricles; Humans; Iodobenzenes; Male; Middle Aged; Myocardium; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Statistics as Topic; Ventricular Dysfunction, Left

The purpose of this study was to verify whether the accuracy of left ventricular parameters related to left ventricular function from gated-SPECT improved or not, using multivariate analysis.. Ninety-six patients with cardiovascular diseases were studied. Gated-SPECT with the QGS software and left ventriculography (LVG) were performed to obtain left ventricular ejection fraction (LVEF), end-diastolic volume (EDV) and end-systolic volume (ESV). Then, multivariate analyses were performed to determine empirical formulas for predicting these parameters. The calculated values of left ventricular parameters were compared with those obtained directly from the QGS software and LVG.. Multivariate analyses were able to improve accuracy in estimation of LVEF, EDV and ESV. Statistically significant improvement was seen in LVEF (from r = 0.6965 to r = 0.8093, p < 0.05). Although not statistically significant, improvements in correlation coefficients were seen in EDV (from r = 0.7199 to r = 0.7595, p = 0.2750) and ESV (from r = 0.5694 to r = 0.5871, p = 0.4281).. The empirical equations with multivariate analysis improved the accuracy in estimating LVEF from gated-SPECT with the QGS software.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Algorithms; Female; Gated Blood-Pool Imaging; Humans; Image Enhancement; Image Interpretation, Computer-Assisted; Male; Middle Aged; Multivariate Analysis; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Software; Stroke Volume; Ventricular Dysfunction, Left

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

The present study evaluates left ventricular performance during exercise by ECG-gated myocardial perfusion SPECT with short-time data collection.. The study population consisted of 10 healthy volunteers (Group N) and 9 patients with ischemic heart disease (Group I). Seven patients in Group I had a history of prior myocardial infarction. Rest ECG-gated SPECT was performed 40 min after an injection of Tc-99m-tetrofosmin (555-740 MBq). After resting data acquisition, Group N underwent up to two 5-min stages of exercise (75 and 125 watts) on a detachable bicycle ergometer. The Group I patients all underwent symptom-limited, maximal testing on the ergometer. ECG-gated SPECT data were acquired from both groups for 3 min at rest and during the last 3 min of each exercise stage.. Significant increases occurred in LVEF from rest to peak stress in both groups (from 55.4 +/- 5.8 to 66.6 +/- 4.1% in group N, p < 0.0001; from 49.0 +/- 12.8 to 56.7 +/- 13.8% in Group I, p < 0.001). The LVESV values significantly decreased to peak stress in Group N (from 49.9 +/- 13.1 to 37.8 +/- 10.0 ml, p < 0.0001), whereas LVEDV did not change (from 110.6 +/- 18.9 to 112.0 +/- 19.0 ml). In contrast, the LVESV values at rest and under peak stress were similar in Group I (from 52.6 +/- 23.9 to 51.7 +/- 31.4 ml) and LVEDV in Group I at peak exercise tended to increase (from 102.8 +/- 36.7 to 111.3 +/- 39.0 ml). The changes in LVESV from rest to peak stress were significantly different between Groups N and I (-12.1 +/- 6.3 vs. -0.9 +/- 11.6 ml, p < 0.02).. ECG-gated SPECT with short-time data collection can assess left ventricular function during exercise and may offer useful information for evaluating patients with ischemic heart disease.

Topics: Adult; Aged; Exercise Test; Female; Gated Blood-Pool Imaging; Humans; Male; Middle Aged; Myocardial Infarction; Myocardial Ischemia; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Rest; Sensitivity and Specificity; 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

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

There is no obvious explanation, except placebo, to the symptomatic effect of transmyocardial laser revascularization (TMR) in patients with refractory angina. Whether TMR improves myocardial perfusion or relieves symptoms without altering cardiac function is not clarified.. One hundred patients with refractory angina were randomized 1:1 to TMR (CO2 laser) and medical treatment, or medical treatment alone. Technetium 99m (99mTc)-tetrofosmin myocardial perfusion tomography (SPECT), quantitative myocardial perfusion gated SPECT (QGSPECT), technetium 99m (99mTc) multiple gated acquisition radionuclide ventriculografi (MUGA) and cine-magnetic resonance imaging (cine-MRI) were performed at baseline and after 3 and 12 months.. Following TMR, a slight reduction in left ventricular ejection fraction (LVEF) (p < 0.05) was observed (MUGA and QGSPECT) compared to baseline. Inclusion of incomplete studies (QGSPECT) revealed a significant reduction in LVEF and increase in left ventricular end-diastolic volume (LVEDV) (p < 0.05) compared to a control group. Otherwise, no between-group comparisons showed statistically significant differences.. TMR did not improve myocardial perfusion, but led to a reduction in LVEF and increase in LVEDV, however not significantly different from the control group.

Topics: Aged; Angina Pectoris; Cardiac Volume; Coronary Circulation; Female; Gated Blood-Pool Imaging; Humans; Magnetic Resonance Imaging, Cine; Male; Middle Aged; Myocardial Revascularization; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Systole; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

New forms of ventricular pacing are increasingly studied as an option in the management of patients with heart failure. Coronary artery disease (CAD) is the most frequent cause of heart failure, and patients with complete left or right bundle branch block (LBBB and RBBB) and a reduced left ventricular ejection fraction (LVEF) are the best candidates for this new therapy. However, the prevalence of this clinical presentation is uncertain. During a 1-year period, 433 patients with documented CAD (mean age 64 +/- 10 years, 79% men) who were referred for myocardial perfusion imaging were prospectively studied. All patients underwent a 2-day stress-rest gated 99mTc-Tetrofosmin SPECT study with evaluation of resting LV enddiastolic (LVEDV) and endsystolic (LVESV) volumes and LVEF. The resting ECG was examined in all patients for the presence of complete LBBB or RBBB. Of the 433 patients with CAD 36 patients (8.3%) had LBBB (n = 14) or RBBB (n = 22) and a QRS width > 120 ms. These 36 patients were in general older and more frequently had diabetes and atrial fibrillation. Patients with LBBB or RBBB had a significantly lower LVEF (41 +/- 16% vs 48 +/- 14%, P < 0.01) and significantly higher LV volumes compared to patients without LBBB or RBBB (177 +/- 79 mL vs 131 +/- 53 mL, P < 0.001 for LVEDV and 116 +/- 76 mL vs 73 +/- 49 mL, P < 0.001 for LVESV). In total, 112/433 (26%) had an LVEF < or = 40%; 16 had also a LBBB or RBBB (3.7% of the whole population, 14% of the patients with a LVEF < or = 40%). Within the group of patients with a LVEF > or = 40%, patients with BBB had comparable LVEF (26 +/- 9% vs 30 +/- 8%, P = NS) but significantly higher LVEDV and LVESV (230 +/- 70 mL vs 190 +/- 64 mL, P < 0.05 for LVEDV and 170 +/- 65 mL vs 135 +/- 56 mL, P < 0.05 for LVESV). In this prospective registry 3.7% of all patients with known CAD had LBBB or RBBB in combination with a LVEF < or = 40%. This represented 14% of all patients with a LVEF > or = 40%. These limited numbers should be kept in mind when considering biventricular pacing as a new therapeutic options in patients with heart failure.

Topics: Aged; Bundle-Branch Block; Cardiac Pacing, Artificial; Cardiac Volume; Coronary Disease; Diabetes Complications; Diabetes Mellitus; Female; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Patient Selection; Prevalence; Prospective Studies; Registries; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left; Ventricular Dysfunction, Right

The purpose of this study was to compare 2 different techniques--dobutamine-atropine stress echocardiography (DSE) and dual-isotope simultaneous acquisition (technetium-99-m-tetrofosmin/fluorine 18-fluorodeoxyglucose) single-photon emission computed tomography (DISA-SPECT)--for assessment of viable myocardium. One hundred ten patients (mean age 55 +/- 9 years) with left ventricular (LV) dysfunction (mean LV ejection fraction 27 +/- 13%) underwent both DISA-SPECT and DSE. A 16-segment scoring model was adopted for both techniques. Four types of wall motion during DSE were assessed: (1) biphasic, improvement at low dose (10 microg/kg/min) with worsening at high dose; (2) worsening, deterioration without initial improvement; (3) sustained, persistent or late improvement; and (4) no change. Viability criteria were biphasic, worsening, and sustained improvement with DSE. Viability criteria with DISA-SPECT were normal perfusion and metabolism (normal), concordantly mildly reduced perfusion and metabolism (subendocardial scar), or severely reduced perfusion and increased metabolism (mismatch). Myocardium was considered nonviable with DSE in case of unchanged wall motion, or moderate reduction or absence in both technetium-99m-tetrofosmin perfusion and fluorodeoxyglucose uptake with DISA-SPECT. Of 1,756 of 1,760 analyzable LV segments, 1,373 (78%) had severe wall motion abnormalities at baseline (severe hypokinesia, akinesia, or dyskinesia). Of these abnormal segments, 282 (21%) were considered viable during DSE (63 [5%] with biphasic response, 47 [3%] with ischemia, and 172 [13%]) with sustained improvement, whereas 1,091 (79%) were considered nonviable. With DISA-SPECT, 396 (29%) segments were considered viable (312 [23%] with matched perfusion/metabolism and 84 [6%] with mismatch), whereas 977 segments (71%) were considered nonviable. Both techniques showed agreement for viability in 201 segments and 896 were concordantly classified as nonviable. Disagreement was present in 276 segments of which 195 (71%) were nonviable with DSE and viable with DISA-SPECT. Overall agreement between the 2 techniques was 81% (kappa 0.46) in a subgroup of patients with an ejection fraction <25% 78% (kappa 0.39). Thus, DSE and DISA-SPECT show good agreement for assessing viable myocardium not influenced by resting ejection fraction. DSE underestimated the amount of viable tissue compared with DISA-SPECT.

Topics: Blood Pressure; Cardiotonic Agents; Dobutamine; Echocardiography; Exercise Test; Fluorodeoxyglucose F18; Heart; Heart Rate; Humans; Male; Middle Aged; Myocardial Infarction; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Stroke Volume; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

Due to partly conflicting studies, further research is warranted with the QGS software package, with regard to the performance of gated FDG PET phase analysis as compared to gated MPS as well as the establishment of possible cut-off values for FDG PET to define dyssynchrony.. Gated MPS and gated FDG PET datasets of 93 patients were analyzed with the QGS software. BW, Phase SD, and Entropy were calculated and compared between the methods. The performance of gated PET to identify dyssynchrony was measured against SPECT as reference standard. ROC analysis was performed to identify the best discriminator of dyssynchrony and to define cut-off values.. BW and Phase SD differed significantly between the SPECT and PET. There was no significant difference in Entropy with a high linear correlation between methods. There was only moderate agreement between SPECT and PET to identify dyssynchrony. Entropy was the best single PET parameter to predict dyssynchrony with a cut-off point at 62%.. Gated MPS and gated FDG PET can assess LVMD. The methods cannot be used interchangeably. Establishing reference ranges and cut-off values is difficult due to the lack of an external gold standard. Further prospective research is necessary.

Topics: Fluorodeoxyglucose F18; Humans; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

Topics: Aged, 80 and over; Bile Ducts; Dilatation; Disease Progression; Echocardiography; Humans; Incidental Findings; Liver; Male; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Pancreatic Neoplasms; Perfusion; Purines; Pyrazoles; Syncope; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

Phase analysis of gated single photon emission computed tomography (SPECT) myocardial perfusion scintigraphy provides a measure of left ventricular dyssynchrony and may have applications for identifying patients suitable for cardiac resynchronisation therapy. Phase analysis is typically described in degrees of cardiac cycle, less intuitive to cardiologists familiar with ECGs. We assessed the relationship between time and degrees, to determine whether they are interchangeable.. 399 patients underwent normal stress-only SPECT myocardial perfusion imaging using Technetium-99m-tetrofosmin. Data analysis used QGS software (Cedars Sinai) calculating bandwidth and standard deviation. Heart rate, age, gender, stress modality, and ejection fraction were analyzed for their relation to phase variables. 13 patients were excluded for conduction abnormalities including right and left bundle branch block and ventricular pacing. Heart rate was strongly correlated to bandwidth and standard deviation measured in time, but unrelated when measured in degrees. Although bandwidth measured by time and degrees were strongly correlated with each other this relationship was not perfect (correlation coefficient 0.87, P < .001). The addition of heart rate to the model explained most of the residual variation between the two. The results for standard deviation were similar.. In patients with normal myocardial perfusion and QRS duration bandwidth measured by degrees is not directly interchangeable with time in milliseconds. However most of the variation is explainable by heart rate, which predominantly affects measures of time rather than degrees. We would propose that although the values are less intuitive to cardiologists, normal ranges for phase measured in degrees are potentially more robust.

Topics: Aged; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; Decision Making; Electrocardiography; Female; Heart Rate; Heart Ventricles; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Reproducibility of Results; Retrospective Studies; Software; Stress, Physiological; Tomography, Emission-Computed, Single-Photon; User-Computer Interface; Ventricular Dysfunction, Left

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

The aim of this study was to define reference values for left ventricular systolic synchrony and for the volume parameters of the left ventricle using myocardial perfusion SPECT-derived phase analysis method.. We evaluated data of 433 patients who underwent myocardial perfusion SPECT/CT during January 2012-February 2013 in Kuopio University Hospital. The final study population consisted of 52 patients (aged 42-84 years) who met the criteria: (1) no previously diagnosed cardiac disease, (2) normal ECG at rest, (3) no advanced coronary artery disease in CT and 4) normal myocardial perfusion in stress/rest myocardial perfusion SPECT/CT. The severity of mechanical dyssynchrony was assessed by phase analysis of gated myocardial SPECT at stress stage after pharmacological exercise and at rest using Quantitative Gated SPECT (QGS) software. Volume parameters of the left ventricle were also assessed.. The phase histogram bandwidth at rest was 28.0 [63.7] degrees (median [95th percentile]). The standard deviation of phase histogram at rest was 7.8 [26.5] degrees. Entropy at the rest study was 54.0 [63.7] %. All left ventricular dyssynchrony parameters were statistically significantly higher at stress compared to rest. There were no statistically significant differences in dyssynchrony values between men and women. In volume parameters, reference values in male were expectedly higher than in female. Cardiac output did not differ significantly between genders.. In subjects without signs of cardiac diseases, the left ventricular systolic function is well synchronized. Phase analysis measurement does not depend on gender, age, BMI or blood pressure, but the values of dyssynchrony parameters increase during pharmacological stress.

Topics: Adenosine; Adult; Aged; Aged, 80 and over; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; Electrocardiography; Female; Humans; Image Interpretation, Computer-Assisted; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Predictive Value of Tests; Radiopharmaceuticals; Reference Values; Reproducibility of Results; Retrospective Studies; Severity of Illness Index; Single Photon Emission Computed Tomography Computed Tomography; Software; Systole; Vasodilator Agents; Ventricular Dysfunction, Left; Ventricular Function, Left

Two-dimensional echocardiographic left ventricular (LV) global longitudinal strain (GLS) after ST-segment elevation myocardial infarction (STEMI) is moderately correlated with infarct size and reflects the residual LV systolic function. This correlation may be influenced by the presence of myocardial ischemia. The present study investigated how myocardial ischemia modulates the correlation between LV GLS and infarct size determined with single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) in patients with first STEMI treated with primary coronary intervention. A total of 1,128 patients (age 60 ± 11 years) who underwent SPECT MPI for the evaluation of infarct size and residual ischemia were evaluated. LV GLS was measured on transthoracic echocardiography. The time interval between echocardiography and SPECT MPI was 1 ± 1 month. A moderate correlation between echocardiographic LV GLS and infarct size on SPECT MPI was observed (r = 0.58, p <0.001). This correlation was weakened by the presence or extent of ischemia; in the group of patients without ischemia, the correlation between LV GLS and infarct size on SPECT MPI was r = 0.66 (p <0.001), whereas in patients with mild or moderate-to-severe ischemia, the correlations were r = 0.56 and 0.38, respectively (both p <0.001). Moderate-to-severe myocardial ischemia was independently associated with more impaired LV GLS after adjusting for infarct size, age, diabetes mellitus, and hypertension (β 0.60, 95% confidence interval 013 to 1.06). In conclusion, the presence of myocardial ischemia after STEMI impacts on the correlation between echocardiographic LV GLS and infarct size measured on SPECT MPI. Residual ischemia is independently associated with more impaired LV GLS.

Topics: Echocardiography; Female; Humans; Image Interpretation, Computer-Assisted; Male; Middle Aged; Myocardial Infarction; Myocardial Ischemia; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Retrospective Studies; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

The association between left ventricular (LV) dyssynchrony parameters, given by phase analysis of gated single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI), and acquisition orbits is unclear. The aim of this study was to assess the dependence of LV dyssynchrony parameters on acquisition orbits.. Ninety-nine patients who underwent. Between 360° and 180° images with. Differences in acquisition orbit had a significant influence on HBW and PSD with

Topics: Aged; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; Female; Heart Ventricles; Humans; Image Processing, Computer-Assisted; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Perfusion; Radiopharmaceuticals; Technetium; Thallium Radioisotopes; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

The purpose of this study was to develop and validate new approaches to quantitative MIBG myocardial SPECT imaging in heart failure (HF) subjects.. Quantitative MIBG myocardial SPECT analysis methods, alone and in conjunction with 99mTc-tetrofosmin perfusion SPECT, were adapted from previously validated techniques for the analysis of SPECT and PET perfusion imaging. To account for underestimation of MIBG defect severity in subjects with global reduction in uptake, a mixed reference database based on planar heart/mediastinum (H/M) ratio categories was used. Extent and severity of voxel-based defects and number of myocardial segments with significant dysinnervation (derived score ≥2) were determined. MIBG/99mTc-tetrofosmin mismatch was quantified using regions with preserved innervation as the reference for scaling 99mTc-tetrofosmin voxel maps. Quantification techniques were tested on studies of 619 ischemic (I) and 319 non-ischemic (NI) HF subjects. Using all analytical techniques, IHF subjects had significantly greater and more severe MIBG SPECT abnormalities compared with NIHF subjects. Innervation/perfusion mismatches were also larger in IHF subjects. Findings were consistent between voxel- and myocardial-segment-based quantitation methods.. Multiple objective methods for quantitation of MIBG SPECT imaging studies provided internally consistent results for distinguishing the different patterns of uptake between IHF and NIHF subjects.

Topics: 3-Iodobenzylguanidine; Adult; Aged; Aged, 80 and over; Female; Heart Failure; Humans; Image Enhancement; Image Interpretation, Computer-Assisted; Machine Learning; Male; Middle Aged; Multimodal Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Pattern Recognition, Automated; Reproducibility of Results; Sensitivity and Specificity; Stroke Volume; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

The aim of the study was to compare the myocardial perfusion defects in patients with right ventricular outflow tract (RVOT) and right ventricular apex (RVA) pacing on stress-rest Tc-tetrofosmin myocardial perfusion single-photon emission computed tomography.. A total of 31 patients with permanent pacemakers (RVOT: 16 and RVA: 15) underwent stress-rest Tc-tetrofosmin involving a 1-day protocol. All patients underwent 1-day low-dose stress-gated and high-dose rest-gated Tc-tetrofosmin myocardial perfusion single-photon emission computed tomography imaging.. Fixed perfusion defects were noted in 13 (42%) of 31 patients. Two (13%) patients of the RVOT group and 11 (69%) patients of the RVA group showed fixed perfusion defects (P=0.003). The fixed perfusion defects were located in the anteroapical, anteroseptal, and apical in the RVOT pacing group and in the apical, distal anteroseptal, inferoapical, distal anterior, and distal inferoseptal in the RVA pacing group. On univariate analysis, the incidence of perfusion defects was significantly associated with apical pacing, longer pQRS duration, and higher percentage of ventricular pacing. On multivariate analysis, the site of pacemaker insertion was found to be the most important pacemaker parameter determining the incidence of perfusion defects. Importantly, the duration of postpacemaker implantation did not show any significant relation to the incidence of perfusion defects.. Fixed perfusion abnormalities are observed in patients with pacemakers and are independent of duration of time since implantation. RVOT pacing is associated with fewer incidences of myocardial perfusion abnormalities compared with RVA pacing.

Topics: Adult; Coronary Circulation; Female; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Pacemaker, Artificial; Rest; Stress, Physiological; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left; Young Adult

Prone positioning is required in certain operations such as spinal surgery. Changes in cardiac function in the prone position have been studied with various methodologies. Few studies have investigated changes in left ventricular diastolic function and rhythm in subjects turned prone.. Cardiac function was evaluated in the supine and prone positions in 90 patients without atrial fibrillation who underwent (99m)Tc-tetrofosmin quantitative gated single-photon emission computed tomography. Three groups of 30 patients each were classified as "no history of myocardial ischemia or cardiomyopathy" (Group A), "history of myocardial infarction" (Group B), and "ischemic heart disease without myocardial infarction history" (Group C). Upon assuming the prone position, the cardiac index and any dyssynchrony worsened in all groups. Ejection fraction changes occurred only in Group B, and diastolic function changes occurred in Groups B and C, but not in Group A. The changes caused by prone positioning were more severe in the patients with poor cardiac function.. Prone positioning induces significant changes in systolic and diastolic function, as well as dyssynchrony. The negative effects of prone positioning are more severe in patients with poor baseline cardiac function.

Topics: Aged; Artifacts; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; Female; Humans; Image Interpretation, Computer-Assisted; Male; Organophosphorus Compounds; Organotechnetium Compounds; Patient Positioning; Prone Position; Radiopharmaceuticals; Reproducibility of Results; Semiconductors; Sensitivity and Specificity; Stroke Volume; Supine Position; Ventricular Dysfunction, Left

To evaluate the relationships among myocardial sympathetic innervation, perfusion and mechanical synchronicity assessed with cardiac cadmium-zinc-telluride (CZT) scintigraphy.. A group of 29 patients underwent an evaluation of myocardial perfusion with (99m)Tc-tetrofosmin CZT scintigraphy and adrenergic innervation with (123)I-metaiodobenzylguanidine (MIBG) CZT scintigraphy. The summed rest score (SRS), motion score (SMS) and thickening score (STS), as well as the summed (123)I-MIBG defect score (SS-MIBG), were determined. Regional tracer uptake for both (99m)Tc-tetrofosmin and (123)I-MIBG was also calculated. Finally, the presence of significant myocardial mechanical dyssynchrony was evaluated in phase analysis on gated CZT images and the region of latest mechanical activation identified.. Significant mechanical dyssynchrony was present in 17 patients (59 %) and associated with higher SRS (P = 0.030), SMS (P < 0.001), STS (P = 0.003) and early SS-MIBG (P = 0.037) as well as greater impairments in left ventricular ejection fraction (P < 0.001) and end-diastolic volume (P < 0.001). In multivariate analysis a higher end-diastolic volume remained the only predictor of mechanical dyssynchrony (P = 0.047). Interestingly, while in the whole population regional myocardial perfusion and adrenergic activity were strongly correlated (R = 0.68), in patients with mechanical dyssynchrony the region of latest mechanical activation was predicted only by greater impairment in regional (123)I-MIBG uptake (P = 0.012) that overwhelmed the effect of depressed regional perfusion.. Left ventricular mechanical dyssynchrony is associated with greater depression in contractile function and greater impairments in regional myocardial perfusion and sympathetic activity. In patients with dyssynchrony, the region of latest mechanical activation is characterized by a significantly altered adrenergic tone.

Topics: 3-Iodobenzylguanidine; Aged; Cadmium; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; Female; Gamma Cameras; Heart Ventricles; Humans; Male; Middle Aged; Myocardial Contraction; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Stroke Volume; Sympathetic Fibers, Postganglionic; Tellurium; Ventricular Dysfunction, Left; Zinc

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

Because left ventricular (LV) diastolic dysfunction is frequently the earliest indicator of LV dysfunction in patients with heart failure, the estimation of LV diastolic function is very important. On the other hand, electrocardiography (ECG)-gated technetium (Tc) -99m tetrofosmin single-photon emission computed tomography (SPECT) has been reported to be a useful method for evaluation of LV function. The objective of this study was to examine the usefulness of ECG-gated Tc-99m tetrofosmin SPECT in terms of estimation of cardiac diastolic function. Consecutive 145 patients underwent an ECG-gated Tc-99m tetrofosmin SPECT to estimate systolic and diastolic LV function, and were compared with those evaluated by ultrasound echocardiography (UCG). LV end-diastolic volume, LV end-systolic volume, and LV ejection fraction values obtained by quantitative gated SPECT (QGS) showed significant positive linear correlations with those obtained by UCG. All 145 patients were classified into 3 groups according to diastolic function estimated by UCG. The first-third mean filling rate (1/3 MFR) and peak filling rate (PFR) that revealed the LV diastolic function of the group B (normal systolic function and mild diastolic dysfunction) patients (1.01 ± 0.35, 1.85 ± 0.57) were both significantly lower than those of the group A (normal systolic and diastolic function) patients (1.43 ± 0.37, 2.43 ± 0.56). The 1/3 MFR and PFR of the group C (moderate ~ severe systolic and diastolic dysfunction) patients (0.47 ± 0.34, 0.92 ± 0.62) were also significantly lower than those of the group A and B patients. QGS may be a useful method for the evaluation of cardiac systolic and diastolic function, especially in patients with normal systolic function and diastolic dysfunction.

Topics: Adult; Aged; Aged, 80 and over; Diastole; Electrocardiography; Female; Follow-Up Studies; Gated Blood-Pool Imaging; Heart Ventricles; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Retrospective Studies; Systole; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left; Ventricular Function, Left

There are limited data on the effect of tracer dose on the reproducibility and accuracy of left ventricular (LV) mechanical dyssynchrony indices by phase analysis of gated single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI).. We measured LV dyssynchrony in 54 patients with normal LV ejection and perfusion (group 1) and 54 age and gender matched patients with LV ejection <35% (group 2) using phase analysis of gated SPECT MPI from stress (high dose) and rest (low dose) studies with 2 software programs: Corridor4DM (4DM) and Emory Cardiac Toolbox (ECTb). Although the correlation between rest- and stress-derived standard deviation was good (R = 0.76, P < .0001, with both software programs), there was considerable variability between the measurements (P < .0001 by paired t test). In addition, the rest standard deviation was significantly higher than stress in group 1 (10.2° ± 4.6° vs 6.1° ± 2.5°, and 12.2° ± 6.4° vs 7.9° ± 4.6°, with 4DM and ECTb, respectively, P < .0001 for both) and group 2 patients (44.0° ± 18.0° vs 35.9° ± 21.0° and 47.3° ± 19.2° vs 38.8° ± 19.8°, with 4DM and ECTb, P = .03 and .02, respectively). Similarly, the rest standard deviations were higher than the stress values irrespective of the type of stress test (i.e., exercise vs pharmacological), and the body mass index. Finally, using rest-derived dyssynchrony indices was associated with 9%-13% and 22%-26% false positive rate of significant mechanical dyssynchrony using different cut-off values for groups 1 and 2, respectively.. LV mechanical dyssynchrony indices by phase analysis have more variation and are significantly higher if derived from rest gated SPECT images obtained with low-dose tracer.

Topics: Aged; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; Dose-Response Relationship, Drug; Female; Humans; Image Enhancement; Image Interpretation, Computer-Assisted; Male; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Ventricular Dysfunction, Left

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

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

The purpose of this study was to compare contrast-enhanced MRI and nuclear imaging with (99m)Tc-tetrofosmin and (18)F-fluorodeoxyglucose ((18)F-FDG) single photon emission computed tomography (SPECT) for assessment of myocardial viability.. Included in the study were 60 patients with severe ischaemic left ventricular (LV) dysfunction who underwent contrast-enhanced MRI, (99m)Tc-tetrofosmin and (18)F-FDG SPECT. Myocardial segments were assigned a wall motion score from 0 (normokinesia) to 4 (dyskinesia) and a scar score from 0 (no scar) to 4 (76-100% transmural extent). Furthermore, (99m)Tc-tetrofosmin and (18)F-FDG segmental tracer uptake was categorized from 0 (tracer activity >75%) to 3 (tracer activity <25%). Dysfunctional segments were classified into viability patterns on SPECT: normal perfusion/(18)F-FDG uptake, perfusion/(18)F-FDG mismatch, and mild or severe perfusion/(18)F-FDG match.. Minimal scar tissue was observed on contrast-enhanced MRI (scar score 0.4+/-0.8) in segments with normal perfusion/(18)F-FDG uptake, whereas extensive scar tissue (scar score 3.1+/-1.0) was noted in segments with severe perfusion/(18)F-FDG match (p < 0.001). High agreement (91%) for viability assessment between contrast-enhanced MRI and nuclear imaging was observed in segments without scar tissue on contrast-enhanced MRI as well as in segments with transmural scar tissue (83%). Of interest, disagreement was observed in segments with subendocardial scar tissue on contrast-enhanced MRI.. Agreement between contrast-enhanced MRI and nuclear imaging for assessment of viability was high in segments without scar tissue and in segments with transmural scar tissue on contrast-enhanced MRI. However, evident disagreement was observed in segments with subendocardial scar tissue on contrast-enhanced MRI, illustrating that the nonenhanced epicardial rim can contain either normal or ischaemically jeopardized myocardium.

Topics: Aged; Cardiology; Contrast Media; Female; Fluorodeoxyglucose F18; Heart; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Myocardium; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

This study sought to find among clinical, hemodynamic and left ventricular perfusion and function data obtained from myocardial perfusion scintigraphy (MPS), those associated with a reduced heart rate (HR) response to dipyridamole in diabetic patients. This phenomenon, although previously described as a marker of autonomic dysfunction in patients with diabetes, has not been fully elucidated.. One hundred two consecutive diabetic patients undergoing dual-isotope (rest Tl-201/dipyridamole stress Tc-99m tetrofosmin) MPS were prospectively enrolled. A reduced HR response to dipyridamole was considered present if the ratio between maximal HR after dipyridamole infusion and rest HR was

Topics: Aged; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Dipyridamole; Female; Heart Rate; Humans; Male; Middle Aged; Myocardial Perfusion Imaging; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Ventricular Dysfunction, Left

(123)I-beta-methyl-iodophenyl pentadecanoic acid (BMIPP) and (99m)Tc-Tetrofosmin (TF) mismatch designated as stunned myocardium having both systolic and diastolic components. The degree of mismatch might reflect subsequent functional improvement, and this study was designed to unravel the impact of mismatched defect score (MMDS) on recovery of both systolic and diastolic function following acute myocardial infarction (AMI). Forty patients with recent AMI were recruited, and all of them underwent emergency percutaneous coronary intervention. Echocardiography and BMIPP and TF cardiac scintigraphy were performed on 7 +/- 3 days of admission. Follow up echocardiography was performed after 3 months. MMDS were compared with the systolic [ejection fraction (EF) and wall motion score index (WMSI)] and diastolic [peak velocity of early diastolic filling of mitral inflow/peak early diastolic velocity of the mitral annulus(E/E') and left atrial volume index(LAVI)] parameters. BMIPP defect score was significantly higher than the TF defect score and there was a strong positive correlation between them (r = 0.90, P < 0.00001). Thirty-two (80%) patients showed mismatched defect and rest 8(20%) showed matched defect. Of 32 patients 24(75%), 22(69%), 19(59%), and 20(62.5%) showed improved EF, WMSI, E/E' and LAVI respectively. Conversely out of 8 only 2(25%), 1(12.5%), and 2(25%) patients showed improvement of EF, WMSI and LAVI, respectively. E/E' was not improved in patients with matched defect. MMDS were significantly correlated with the improvement of EF (r = -0.46, P = 0.002), WMSI (r = 0.41, P = 0.007), E/E' (r = 0.56, P < 0.0002), and LAVI (r = 0.44, P = 0.004). Mismatched defect score could predict the approximate amount of viable dysfunctional myocardium, and the degree of mismatch showed a significant correlation with the improvement of both systolic and diastolic function.

Topics: Aged; Angioplasty, Balloon, Coronary; Cross-Sectional Studies; Echocardiography, Doppler; Fatty Acids; Female; Humans; Iodine Radioisotopes; Iodobenzenes; Male; Middle Aged; Myocardial Infarction; Myocardial Perfusion Imaging; Myocardial Stunning; Organophosphorus Compounds; Organotechnetium Compounds; Predictive Value of Tests; Prospective Studies; Radiopharmaceuticals; Recovery of Function; Stroke Volume; Time Factors; Tomography, Emission-Computed, Single-Photon; Treatment Outcome; Ventricular Dysfunction, Left; Ventricular Function, Left

The purpose of this study was to clarify the relationship between reverse redistribution (RRD) of (99m)Tc-tetrofosmin ((99m)Tc-TF) and left ventricular functional recovery in patients with acute myocardial infarction (AMI).. We studied 21 patients with AMI who underwent direct percutaneous coronary intervention (PCI). (99m)Tc-TF-gated single-photon emission computed tomography (SPECT) was performed at rest in the sub-acute and chronic phases. Imaging data were acquired at 30 min (early images) and 3 h (delayed images) after injection. Defect score, regional relative uptakes of (99m)Tc-TF (%uptake), and regional wall thickening (WT) were calculated using the 20-segment model. We measured left ventricular ejection fraction (LVEF) and defined DeltaLVEF as change in LVEF. Summed defect score was calculated by adding the scores of 20 segments on early and delayed images. Summed washout score (SWS) was derived as the difference between early and delayed scores. We defined that SWS was more than 1 point as individual RRD (I-RRD). In each segment, regional RRD (R-RRD) in the sub-acute phase was calculated as %uptake on early images minus %uptake on delayed images in the sub-acute phase. DeltaWT was defined as change in WT from the sub-acute phase to chronic phase. We defined that R-RRD and DeltaWT were higher than 1SD on the control map as R-RRD (+) and change of WT (+).. All patients were divided into two groups according to the presence of I-RRD. DeltaLVEF was significantly higher in I-RRD (+) than in I-RRD (-) (14.5 +/- 12.1 vs. 0.0 +/- 3.9%, p < 0.01). We analyzed 162 segments as at-risk areas among a total of 420 segments. In total of R-RRD (+), 75 of 96 segments (78%) had change of WT (+), while this was observed in only 13 of 66 segments (20%) in total of R-RRD (-) (p < 0.0001). In addition, there was a significant correlation between R-RRD in the sub-acute phase and change in %uptake on delayed images from the sub-acute phase to chronic phase in at-risk areas (r = 0.584, p < 0.001).. These findings suggested that quantitative evaluation of RRD by gated (99m)Tc-tetrofosmin SPECT in the sub-acute phase can predict recovery of left ventricular function in the chronic phase with higher accuracy in patients with AMI who underwent direct PCI.

Topics: Female; Humans; Male; Middle Aged; Myocardial Infarction; Organophosphorus Compounds; Organotechnetium Compounds; Recovery of Function; Time Factors; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

The noninvasive differentiation of ischemic from nonischemic cardiomyopathy is clinically important. However, whether adenosine Tc-99m tetrofosmin SPECT can offer clear and accurate information was not known. The aim of this study is to investigate the usefulness of adenosine Tc-99m tetrofosmin SPECT in differentiation of ischemic from nonischemic etiology in patients with mild to severe LV systolic dysfunction and to compare the relationship between patients with mild LV systolic dysfunction and those with severe LV systolic dysfunction.. Seventy-five patients with chronic heart failure (LV ejection fraction 35%, group II (31 patients) had severe LV dysfunction, LVEF or=20%. Myocardial ischemia was defined by >or=70% stenosis in at least one vessel by coronary angiography.. : In group I, 4 (30.8%) of 13 patients with small defects, 1 (25.0%) of 5 patients with a medium defect, and 22 (84.6%) of 26 patients with large defects demonstrated myocardial ischemia documented by coronary angiography. The relationship between the extent of the SPECT defect and myocardial ischemia was statistically significant in the group I population (P < 0.001). However, in group II, 1 (33.3%) of 3 patients with small defect, 3 (33.3%) of 9 patients with medium defects, and 7 (36.8%) of 19 patients with large defects demonstrated myocardial ischemia confirmed by coronary angiography. There was no statistical relationship between the extent of the SPECT defect and myocardial ischemia in group II.. Adenosine Tc-99m tetrofosmin SPECT is a useful modality to differentiate ischemic from nonischemic etiology in patients with mild LV systolic dysfunction. However, other noninvasive approaches other this SPECT may be considered for confirming the etiology in patients with severe LV systolic dysfunction.

Topics: Aged; Cardiomyopathies; Coronary Angiography; Echocardiography; Female; Heart Failure; Humans; Male; Middle Aged; Myocardial Ischemia; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Systole; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

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

The aim of this study was to evaluate the value of attenuation correction (AC) of Tc-99m tetrofosmin single-photon emission tomography (SPECT) imaging for the assessment of left ventricular ejection fraction (LVEF).. Attenuation corrected and non-attenuation corrected (NC) resting Tc-99m tetrofosmin SPECT were compared for the assessment of LVEF. Planar multigated radionuclide angiography (MUGA) served as the reference for LVEF assessment. Patients (n = 56) with left ventricular dysfunction who underwent MUGA and rest gated Tc-99m tetrofosmin SPECT within 1 month were included.. The average LVEF on NC gated SPECT was 37.4 +/- 11.8% and on AC SPECT 38.5 +/- 13.4% (P = NS). The absolute mean difference of the LVEF between the MUGA and NC gated SPECT and AC gated SPECT was -0.2% (95% CI -1.7 to 1.3) and -1.3% (95% CI -2.7 to 0.03), respectively (P = NS both vs. MUGA). The correlation between NC gated SPECT and AC gated SPECT versus MUGA measurement was high with a correlation coefficient of 0.89 (P < 0.01) and 0.92 (P < 0.01), respectively. End-diastolic volumes (EDVs) and end-systolic volumes (ESVs) were significantly higher with AC gated SPECT when compared with NC gated SPECT (both P < 0.001).. Profile AC gated Tc-99m tetrofosmin SPECT agrees well with MUGA and NC gated Tc-99m tetrofosmin SPECT for the assessment of LVEF. EDVs and ESVs are significantly higher with AC gated SPECT when compared with NC gated SPECT.

Topics: Aged; Aged, 80 and over; Energy Transfer; Evaluation Studies as Topic; Female; Gated Blood-Pool Imaging; Heart; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Photons; Radiopharmaceuticals; Research Design; Stroke Volume; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

At present, 20-30% of patients do not respond to cardiac resynchronization therapy (CRT). In this study, the relation between the extent of viable myocardium and scar tissue vs. response to CRT was evaluated. In addition, the presence of scar tissue in the left ventricular (LV) lead position was specifically related to response to CRT.. A total of 51 consecutive patients with ischaemic heart failure and substantial LV dyssynchrony undergoing CRT were included. All patients underwent gated SPECT before CRT implantation to determine the extent of scar tissue and viable myocardium. Clinical and echocardiographic parameters were assessed at baseline and after 6 months of CRT. The results demonstrated direct relations between the response to CRT and the extent of viable myocardium and scar tissue. In addition, the 15 patients (29%) with transmural scar tissue (< 50% tracer activity) in the region of the LV pacing lead showed no improvement after 6 months of CRT.. The extent of scar tissue and viable myocardium were directly related to the response to CRT. Furthermore, scar tissue in the LV pacing lead region may prohibit response to CRT. Evaluation for viability and scar tissue may be considered in the selection process for CRT.

Topics: Aged; Cardiac Pacing, Artificial; Cicatrix; Electrocardiography; Female; Heart Failure; Humans; Male; Myocardial Ischemia; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon; Treatment Outcome; Ventricular Dysfunction, Left

Digestive activity can interfere with the interpretation of myocardial perfusion single photon emission computed tomography using sestamibi or tetrofosmin. Compared with sestamibi, the liver clearance of tetrofosmin is more rapid, but its absolute cardiac uptake is lower. In this study, the activity of sestamibi and tetrofosmin was quantified after exercise or pharmacological stress and at rest to objectify the biokinetic differences and to evaluate whether there is a correlation between quantitative measurements and the visual assessment of image quality.. Left ventricular activity and five ratios (R1-R5) of cardiac to adjacent extra-cardiac activity were quantified in 204 sestamibi (68 exercise stress/56 pharmacological stress/80 rest) and 221 tetrofosmin (67 exercise stress/59 pharmacological stress/95 rest) studies. Image quality was assessed by a three-point score (1, good; 2, moderate; 3, poor) and correlated with the heart to left supra-diaphragmatic region (R1) and heart to right supra-diaphragmatic region (R2) ratios.. The mean left ventricular activity was higher for sestamibi, especially at rest (sestamibi, 0.21+/-0.05 counts/pixel/injected MBq; tetrofosmin, 0.16+/-0.042 counts/pixel/injected MBq; P<0.001). By contrast, most ratios were higher with tetrofosmin, particularly for the exercise stress and rest studies. Using the three-point quality scoring, more sestamibi than tetrofosmin studies were scored as 3 (12.2% versus 6.3%), also particularly for the exercise stress and rest studies. A highly significant relationship was found between decreasing R1 and R2 and an increasing quality score, regardless of the radiopharmaceutical used (P values between 0.02 and <0.001).. Despite a lower cardiac uptake, the more rapid liver clearance of tetrofosmin than sestamibi significantly improves the ratios of cardiac to digestive activity, especially after exercise or at rest. These quantitative differences in biokinetics result in less poor scans with tetrofosmin in daily practice.

Topics: Artifacts; Digestion; Exercise Test; Female; Humans; Kinetics; Liver; Male; Metabolic Clearance Rate; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Perfusion; Radionuclide Imaging; Radiopharmaceuticals; Reproducibility of Results; Rest; Sensitivity and Specificity; Technetium Tc 99m Sestamibi; Ventricular Dysfunction, Left

Inter-institution reproducibility of gated SPECT quantification based on institutional preferences was evaluated. This sort of variability is crucial for a multicentre study when many hospitals are involved.. A total of 106 institutes participated in this study and were grouped according to their use of five workstation types. Fifteen sets of 99mTc-tetrofosmin gated projection images with normal ejection fraction (EF) (approximately 70%, group A, n = 5), borderline low EF (approximately 50%, group B, n = 5) and low EF with large perfusion defects (approximately 30%, group C, n = 5) were prepared. The projection images were processed by QGS software in each institute based on its own routine settings. Based on 318 QGS results, the reproducibility of EF and volumes was analysed for each group and workstation.. The reproducibility of EF was good in 14 of 15 cases, showing a standard deviation (SD) of <3.6%, and the coefficient of variance of the end-diastolic volume (EDV) was <9.3% in all cases. When the deviation from the average value was analysed, the difference between EF at each institute and the average EF of the workstation (dEF) showed an SD of 2.2-3.7% for each group. The ratio of the EDV divided by the average EDV (rEDV) showed an SD of 0.061-0.069 for each group. One case in group C that had a large anterior defect with low EF showed bimodal EF distribution in one of the five workstations. The SD of EF was workstation dependent, owing to the SPECT reconstruction conditions.. The reproducibility in EF and volumes within a workstation was good, even though the gated SPECT preferences varied. This reproducibility study supports the use of gated SPECT as a standard of ventricular function in multicentre studies.

Topics: Data Interpretation, Statistical; Hospitals; Humans; Image Interpretation, Computer-Assisted; Organophosphorus Compounds; Organotechnetium Compounds; Perfusion; Radiopharmaceuticals; Reproducibility of Results; Research Design; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

The purpose of this study was to evaluate the reliability of left ventricular ejection fraction (LVEF) measured by quantitative gated SPECT (QGS). We compared the efficacy of LVEF assessment among Tc-99m tetrofosmin gated SPECT imaging, contrast left ventriculography (LVG), and first-pass radionuclide angiography (FP).. One-hundred and seven patients with ischemic heart disease underwent QGS and LVG simultaneously within 3 months, and 92 of the 107 patients also underwent FP at the same time.. QGS progressively overestimated LVEF at the lower range of end-systolic volume (ESV), especially in patients with small hearts. Moreover, the QGS technique systemically tended to underestimate LVEF in comparison with LVG. However, linear regression analysis demonstrated a good correlation between the LVEF values measured by QGS and those measured by both LVG (p<0.0001) and FP (p<0.0001).. Although QGS has a tendency to overestimate LVEF in patients with small hearts, and to systemically underestimate LVEF compared with LVG, this technique is still a reliable clinical tool for measurement of LVEF.

Topics: Aged; Female; Humans; Linear Models; Male; Middle Aged; Myocardial Ischemia; Organophosphorus Compounds; Organotechnetium Compounds; Radionuclide Angiography; Radionuclide Ventriculography; Radiopharmaceuticals; Reproducibility of Results; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

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

A 70-year-old woman was admitted to our hospital because of left ventricular dysfunction, which was observed after permanent pacemaker implantation in another hospital. The left ventricular dysfunction was apical ballooning. Left ventriculography demonstrated takotsubo-like shape. However, the dysfunction did not improve immediately with medical treatment. In this case, 75% stenosis was observed in the left anterior descending artery. We suppose that this lesion corresponded to the delayed recovery of the dysfunction and performed coronary intervention. The takotsubo-like shape improved gradually for about 1 year. Whether the coronary intervention was effective for the recovery of the dysfunction is unclear, this clinical course was interesting in evaluating the delayed recovery of takotsubo-like left ventricular dysfunction.

Topics: Aged; Cardiomyopathies; Coronary Circulation; Electrocardiography; Female; Heart; Heart Block; Heart Ventricles; Humans; Myocardial Contraction; Organophosphorus Compounds; Organotechnetium Compounds; Pacemaker, Artificial; Radionuclide Imaging; Radiopharmaceuticals; Recovery of Function; Ultrasonography; Ventricular Dysfunction, Left

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

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

Electrocardiogram-gated myocardial single-photon emission computed tomography (SPECT) with (99m)Tc-tetrofosmin allows simultaneous evaluation of myocardial perfusion and function. In this study, left ventricular volumes, ejection fraction (LVEF), and left ventricular wall volume (LVWV) derived from gated SPECT were compared with measurements from cardiovascular magnetic resonance (CMR), performed within a few hours.. The study population included 55 patients with known or suspected coronary artery disease, including 13 patients with recent acute myocardial infarction. End-diastolic (EDV) and end-systolic (ESV) volumes, LVEF and LVWV were derived automatically from gated SPECT using commercially available software (QGS). In the CMR studies, manually delineated endocardial and epicardial borders on short-axis slices were used to calculate the volumes.. Gated SPECT underestimated EDV by 35 +/- 14 ml (mean +/- SD) (P < 0.001), ESV by 10 +/- 13 ml (P < 0.001), and LVEF by 4 +/- 7 percentage points (P < 0.001). There were no systematic difference in EDV, ESV or LVEF between the methods. SPECT underestimated LVWV by 49 +/- 30 ml (P < 0.001), with a trend towards increasing underestimation by SPECT for larger wall volumes.. These findings show that gated SPECT slightly underestimates EDV, ESV and LVEF compared with CMR. This underestimation is systematic, however, indicating that ventricular volumes derived from gated SPECT are robust enough to guide clinical management. Estimates of LVWV in patients with large wall volumes are less accurate.

Topics: Adult; Aged; Aged, 80 and over; Electrocardiography; Female; Gated Blood-Pool Imaging; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Stroke Volume; 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

Ventricular arrhythmias have been shown to originate in the myocardial peri-infarct region due to irregular heterotopic conduction. Hypoperfused but viable myocardium is often localised in those areas and may be involved in the pathogenesis of arrhythmias. We tested the hypothesis that these myocardial perfusion/metabolism mismatches (MM) are significantly associated with ventricular arrhythmias in the chronic post infarction state.. 47 post infarction patients were included in the study. 33 suffered from ventricular arrhythmia whereas 14 did not. All patients underwent (99m)Tc tetrofosmin SPECT and (18)F-FDG PET. A region-of-interest(ROI)-analysis was used to assess viable myocardium based on predefined MM-criteria. Univariate analyses as well as a logistic regression model for the multivariate analysis were carried out.. 94% of the arrhythmic patients displayed at least one MM-segment as compared to 64% of the non-arrhythmic patients. MM-segments and arrhythmia showed a statistically significant relation (p = 0.018). The logistic regression model predicted the occurrence or absence of arrhythmia in 85% of all cases. Multivariate analysis gave consistent results, after adjusting for symptomatic chronic heart failure (CHF), aneurysms and age.. Our results support the hypothesis that hypoperfused but viable myocardium represents an arrhythmogenic substrate and is a relevant risk factor for developing ventricular arrhythmias following myocardial infarction. Therefore, the detection of MM-segments allows the identification of patients with a higher risk for future cardiac events.

Topics: Coronary Disease; Female; Fluorodeoxyglucose F18; Humans; Male; Middle Aged; Myocardial Infarction; Myocardial Reperfusion; Myocardium; Organophosphorus Compounds; Organotechnetium Compounds; Positron-Emission Tomography; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left; Ventricular Fibrillation

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

To assess whether quantification of myocardial systolic velocities by pulsed wave tissue Doppler imaging can differentiate between stunned, hibernating, and scarred myocardium.. Observational study.. Tertiary referral centre.. 70 patients with reduced left ventricular function caused by chronic coronary artery disease.. Pulsed wave tissue Doppler imaging was done close to the mitral annulus at rest and during low dose dobutamine; systolic ejection velocity (Vs) and the difference in Vs between low dose dobutamine and the resting value (DeltaVs) were assessed using a six segment model. Assessment of perfusion (with Tc-99m-tetrofosmin SPECT) and glucose utilisation (by 18F-fluorodeoxyglucose SPECT) was used to classify dysfunctional regions (by resting cross sectional echocardiography) as stunned, hibernating, or scarred.. 253 of 420 regions (60%) were dysfunctional. Of these, 132 (52%) were classified as stunned, 25 (10%) as hibernating, and 96 (38%) as scarred. At rest, Vs in stunned, hibernating, and scar tissue was, respectively, 6.3 (1.8), 6.6 (2.2), and 5.5 (1.5) cm/s (p = 0.001 by ANOVA). There was a gradual decline in Vs during low dose dobutamine infusion between stunned, hibernating, and scar tissue (8.3 (2.6) v 7.8 (1.5) v 6.8 (1.9) cm/s, p < 0.001 by ANOVA). DeltaVs was higher in stunned (2.1 (1.9) cm/s) than in hibernating (1.2 (1.4) cm/s, p < 0.05) or scarred regions (1.3 (1.2) cm/s, p = 0.001).. Quantitative tissue Doppler imaging showed a gradual reduction in regional velocities between stunned, hibernating, and scarred myocardium. Dobutamine induced contractile reserve was higher in stunned regions than in hibernating and scarred myocardium, reflecting different severities of myocardial damage.

Topics: Cicatrix; Coronary Disease; Diagnosis, Differential; Echocardiography; Female; Fluorodeoxyglucose F18; Humans; Male; Middle Aged; Myocardial Contraction; Myocardial Infarction; Myocardial Stunning; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Stroke Volume; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

It has been shown that exercise may lead to the myocardial stunning with reduction of LVEF, persisting for some time despite recovery of perfusion. The aim of this study was to check whether the post-stress decrease of LVEF lasts as long as 3 h after exercise.. The study was performed in 46 patients with CAD and in 10 normals (NMS). All patients underwent myocardial gSPECT after (99m)Tc-tetrofosmin injection at rest and during stress with 2-day protocol. SPECT was started 1h after tracer injection at rest (R) and twice: 1h (S1) and 3hs (S3) after injection at stress. LVEF was calculated by the method of Germano et al.. All LVEF values were significantly lower in CAD patients than in the control group. In NMS mean LVEF was at rest similar to those obtained 1 h and 3 h after stress injection (59.0 +/- 4.1, 60.0 +/- 5.9, 58.0 +/- 4.6, respectively; p >0.05). A post-exercise decrease of LVEF was observed in 2 normal patients both at S1 and at S3. In CAD group LVEF values were lower at S1 than at R (50.8 +/- 13.6 versus 49.3 +/- 12.8; p <0.05) and at S3 were lower than at S1 (49.3 +/- 12.8 versus 46.0 +/- 12.2;p <0.001). A significant decrease of LVEF was found in 18/46 patients 1 h post stress and in 36/46 3 h post stress. In patients with reversible perfusion decrease, a significant correlation was found between post-exercise deterioration of perfusion and post-exercise LVEF reduction both at S1 (r = 0.744; p <0.02) and at S3 (r = 0.734; p <0.02). Stress induced decrease in LVEF correlated also with severity of perfusion abnormalities.. In the majority of patients with CAD physical stress applied for diagnostic purposes results in an impairment of the LV function. A decrease of the LVEF is observed 1 h after exercise, but it increases in frequency and grows stronger during the next 2 h. The post-stress LVEF reduction is related to the severity of perfusion abnormalities. Patients with CAD who underwent diagnostic stress test should remain under observation during several hours after termination of exercise.

Topics: Adult; Aged; Coronary Disease; Exercise Test; Female; Heart; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radioisotopes; Time Factors; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left; Ventricular Function, Left

Topics: Aged; Aged, 80 and over; Female; Follow-Up Studies; Heart Ventricles; Humans; Male; Metabolic Clearance Rate; Middle Aged; Myocardial Infarction; Organophosphorus Compounds; Organotechnetium Compounds; Radionuclide Imaging; Radiopharmaceuticals; Tissue Distribution; Ventricular Dysfunction, Left

An 82-year-old woman was referred to the authors' institution because of an electrocardiographic abnormality mimicking acute myocardial infarction. Left ventriculography showed apical wall hypokinesis and basal wall hyperkinesis. Coronary angiography revealed no organic stenosis. Three days earlier, she was told she had renal cancer. She was diagnosed as having "takotsubo" cardiomyopathy. She underwent early and delayed Tc-99m tetrofosmin single photon emission computed tomography (SPECT). The early SPECT images revealed homogeneous tracer uptake in the left ventricle, but the delayed images revealed decreased uptake in the apical wall. Reverse redistribution of Tc-99m tetrofosmin was observed in this patient with "takotsubo" cardiomyopathy.

Topics: Aged; Aged, 80 and over; Cardiomyopathies; Diagnosis, Differential; Female; Heart; Humans; Organophosphorus Compounds; Organotechnetium Compounds; Radionuclide Imaging; Radiopharmaceuticals; Ventricular Dysfunction, Left

The purpose of this study was to investigate the clinical significance of the reverse redistribution (RR) phenomenon on technetium-99m ((99m)Tc)-tetrofosmin myocardial single photon emission computed tomography (SPECT) performed at rest. Twenty-five patients underwent myocardial SPECT 3 weeks after the onset of acute myocardial infarction. Myocardial images were acquired at 40 min (early) and 4 h (delayed) after the injection of 740 MBq of (99m)Tc-tetrofosmin. The regional myocardial uptake of the tracer in 26 segments of the left ventricular (LV) wall was visually scored from 0 (no activity) to 3 (normal activity), and then the RR was defined as a decrease of more than 1 point in the activity score on the delayed image compared with that on the early image. Regions with an activity score of 3 on both the early and delayed images were defined as normal, and those with a score of 0 or 1 on the early image were considered to have a fixed defect. The regional myocardial (99m)Tc-tetrofosmin uptake and washout rate were also quantitatively assessed in each region. In addition, exercise stress electrocardiograph-gated SPECT with (99m)Tc-tetrofosmin was performed within 1 week of the rest study, and the percent count increase (%CI) during myocardial contraction in each corresponding region was studied. RR was observed in 18 of the 25 patients. The regional washout rate of (99m)Tc-tetrofosmin was significantly higher in the RR regions (45.0+/-3.8%) than in either the normal regions (36.4+/-4.1%, p<0.001) or in those with a fixed defect (39.7+/-3.9%, p<0.001). The %CI in the RR regions (10.4+/-10.4%) was significantly less than that in the normal regions (23.5+/-10.1%, p<0.001); however, no significant difference was found between the RR regions and those with a fixed defect (8.0+/-7.2%). In patients with acute myocardial infarction, the regions showing the RR phenomenon on (99m)Tc-tetrofosmin SPECT have severely impaired LV wall contraction after exercise.

Topics: Aged; Aged, 80 and over; Electrocardiography; Exercise; Female; Humans; Hypertrophy, Left Ventricular; Male; Middle Aged; Myocardial Infarction; Organophosphorus Compounds; Organotechnetium Compounds; Radionuclide Angiography; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

To evaluate whether the post-stress and rest functional parameters, measured by Gated-SPECT, have incremental prognostic value compared with perfusion parameters in predicting cardiac events (CE), in a population of CAD patients with dilated LV.. A total of 670 consecutive patients (mean age: 62; range 29-86 yrs.) underwent conventional diagnostic 2-day gated-SPECT with 99mTc-tetrofosmin (55% exercise stress test, 45% dip stress): 605 patients (mean age: 62 yrs., range: 34-86 yrs.) had known or suspected CAD, whereas 65 (mean age: 60 yrs, range: 29-80 yrs) had low pre-test likelihood of CAD (<10%), a normal post-stress perfusion scan and no hypertension. Fifty-three percent of CAD patients had a history of MI. Perfusion was analyzed on ungated images using 20 segments scored on a 5-point scale (0=normal, 4=no uptake), while wall thickening was assessed visually on stress/rest end-systolic images using a 4-point score (0=normal, 3=absence of WT). LVEF and volumes were calculated using an automatic algorithm. Post-stress and rest ratio were determined for both end-diastolic and end-systolic volume, while the post-stress LVEF change (d-LVEF) was calculated according to the following formula: (Stress LVEF-rest LVEF)/rest LVEF*100.. By using a cutoff value of 126 ml for rest-EDV, and of 68 ml for rest-ESV we found a LV dilation in 129/605 patients (21%). These thresholds were the mean values plus two standard deviations obtained in the control group. 111/129 (86%) were followed up for a mean period of 147.0 months. 83 of 111 (75%) patients had a history of MI and forty three (39%) had undergone surgical revascularizations. During the follow-up, 21 events (5 cardiac deaths, 3 nonfatal MI, 13 late revascularizations) occurred. All post-stress perfusion and functional parameters were more compromised in patients with CE compared with patients without events, but only rest EDV, rest ESV, post-stress ESV and WT-SSS reached statistical significance (201 ml vs 176 ml; p=0.035; 137 ml vs 113 ml; p=0.047; 143 ml vs 117 ml; p=0.034, 19 vs 15; p=0.048, respectively). Multivariate Cox proportional analysis demonstrated that stress ESV added significantly prognostic information over WT-SSS in predicting CE (p=0.046).. Stress ESV has incremental prognostic value compared with wall thickening in predicting CE, in CAD patients with dilated cardiomyopathy. Perfusion parameters failed to show prognostic information in these patients.

Topics: Adult; Aged; Aged, 80 and over; Analysis of Variance; Coronary Angiography; Coronary Disease; Exercise Test; Female; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Proportional Hazards Models; Radiopharmaceuticals; Rest; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

To assess the prevalence of myocardial viability by technetium-99m (Tc-99m)-tetrofosmin/fluorine-18-fluorodeoxyglucose (FDG) single photon emission computed tomography (SPECT) in patients with ischaemic cardiomyopathy.. A retrospective observational study.. Thoraxcenter Rotterdam (a tertiary referral centre).. 104 patients with chronic coronary artery disease and severely depressed left ventricular function presenting with heart failure symptoms.. Prevalence of myocardial viability as evaluated by Tc-99m-tetrofosmin/FDG SPECT imaging. Two strategies for assessing viability in dysfunctional myocardium were used: perfusion imaging alone, and the combination of perfusion and metabolic imaging.. On perfusion imaging alone, 56 patients (54%) had a significant amount of viable myocardium, whereas 48 patients (46%) did not. Among the 48 patients with no significant viability by perfusion imaging alone, seven additional patients (15%) had significantly viable myocardium on combined perfusion and metabolic imaging. Thus with a combination of perfusion and metabolic imaging, 63 patients (61%) had viable myocardium and 41 (39%) did not.. On the basis of the presence of viable dysfunctional myocardium, 61% of patients with chronic coronary artery disease and depressed left ventricular ejection fraction presenting with heart failure symptoms may be considered for coronary revascularisation. The combination of perfusion and metabolic imaging identified more patients with significant viability than myocardial perfusion imaging alone.

Topics: Coronary Circulation; Coronary Vessels; Female; Fluorodeoxyglucose F18; Humans; Male; Middle Aged; Myocardial Contraction; Myocardial Ischemia; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Retrospective Studies; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

18F-FDG is a well-established tracer for evaluating myocardial viability, as is (99m)Tc-tetrofosmin (TET) for evaluating myocardial perfusion. Dual-isotope single-acquisition (DISA) studies using a (99m)Tc perfusion agent and (18)F-FDG have been performed to evaluate myocardial viability. The purpose of this investigation was to determine whether there is a difference in the results of gated SPECT DISA, compared with gated SPECT DIDA (dual-isotope dual-acquisition) studies using (99m)Tc-TET/(18)F-FDG and a high-energy collimated dual-head SPECT system.. We prospectively studied 13 patients with depressed left ventricular function using both acquisition protocols. Summed rest scores were calculated for both (99m)Tc and (18)F-FDG studies using a 12-segment model and a 5-grade severity score. Images were evaluated by a single reader who did not know whether the images were acquired separately or simultaneously.. The concordance of DISA and DIDA protocols for (99m)Tc-TET when allowing no difference in the SRS was 57%, or 89 of 156 segments. The concordance of DISA and DIDA protocols for (18)F-FDG was 86%, or 134 of 156 segments. The concordance of segments determined to be viable versus nonviable was 92%, or 143 of 156 segments. Ejection fraction measurements obtained by gated (99m)Tc-TET studies correlated strongly with those obtained by gated (18)F-FDG studies.. A high concordance for (18)F-FDG studies was shown between gated DISA and gated DIDA. A lower concordance was shown between gated DISA and gated DIDA studies using (99m)Tc-TET, most likely because of downscatter from (18)F into the (99m)Tc window. An excellent concordance was demonstrated between the 2 techniques for viability assessment. The gated (99m)Tc-TET/(18)F-FDG DISA protocol can be both a reliable and an efficient way to evaluate myocardial function, perfusion, and viability.

Topics: Fluorodeoxyglucose F18; Gated Blood-Pool Imaging; Humans; Organophosphorus Compounds; Organotechnetium Compounds; Prospective Studies; Radiopharmaceuticals; Single-Blind Method; Statistics as Topic; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

Increased lung uptake of thallium-201 (Tl-201) and technetium-99m (Tc-99m) MIBI in myocardial perfusion imaging is a reliable marker of left ventricular dysfunction. The goal of our study was to establish whether the lung-to-heart (L/H) uptake ratio with a newer cardiac imaging agent, Tc-99m tetrofosmin, can also provide valuable information about left ventricular function. We studied 60 patients with recent coronary artery diseases (CAD) undergoing first-pass radionuclide ventriculography to calculate left ventricular ejection fraction (LVEF) and myocardial perfusion imaging to calculate the L/H ratio. Group A consisting of 30 CAD patients with higher LVEF (> or =40%) had a significantly lower L/H ratio than group B consisting of 30 CAD patients with abnormal LVEF (<40%) during exercise and rest. In groups A and B, the exercise and rest L/H ratios did not differ significantly. However, a statistically significant inverse correlation was found between the L/H ratio and LVEF during exercise and rest among the 60 patients. L/H ratios, measured by 99mTc-tetrofosmin imaging, provide clinically useful information with which to predict left ventricular dysfunction in CAD patients.

Topics: Adult; Aged; Coronary Disease; Exercise; Exercise Test; Female; Humans; Lung; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Rest; Stroke Volume; Technetium Tc 99m Sestamibi; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left; Ventricular Function, Left; Ventriculography, First-Pass

A 57-year-old woman was emergently admitted to our hospital because of chest oppression. On examination, blood pressure was 174/96 mmHg, pulse rate was 90/min and coarse crackle and third heart sound were audible. On laboratory data, the levels of LDH and CPK-MB were mildly elevated. Electrocardiogram (ECG) demonstrated elevation of the ST segment in leads I, aVL and V2-V5. 99mTc-tetrofosmin myocardial SPECT (TF) showed severely reduced uptake in the apex and anterior wall. Emergent coronary angiography (CAG) did not show any stenotic lesion. Left ventriculography (LVG), however, demonstrated akinesis of the apex, anterior, and inferior walls, and basal hyperkinesis. On the second hospital day, ECG demonstrated inverted T wave in leads I, aVL and V2-V5. 123I-BMIPP myocardial SPECT (BMIPP) and 123I-MIBG myocardial SPECT (MIBG) were performed on the second and fourth hospital days, respectively. These cardiac images showed severely reduced uptake equally. TF, BMIPP, and MIBG were re-examined on the eighth, tenth, and twelfth hospital days, respectively. MIBG, BMIPP, and TF showed reduced uptake in order of severity. On the fourteenth hospital day, CAG and LVG were re-examined. Coronary vasospasm provocation test was negative using ergonovine and acetylcholine, and LVG did not demonstrated any sign of asynergy. We considered that this case was "Takotsubo" cardiomyopathy and might be caused by microvascular spasm.

Topics: 3-Iodobenzylguanidine; Acute-Phase Reaction; Cardiomyopathies; Coronary Vasospasm; Fatty Acids; Female; Gated Blood-Pool Imaging; Heart; Humans; Iodine Radioisotopes; Iodobenzenes; Microcirculation; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

Topics: Aged; Dipyridamole; Exercise Test; Gastrectomy; Gastroesophageal Reflux; Humans; Male; Organophosphorus Compounds; Organotechnetium Compounds; Peptic Ulcer; Radiopharmaceuticals; Sensitivity and Specificity; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

We investigated the prognostic value of 99mTc-Tetrofosmin myocardial SPECT (99mTc-TF) in dysfunctional multivessel coronary disease patients who underwent revascularization (RV) or only medical treatment (MT).. In 78 coronary patients with 2-3 diseased vessels and left ventricular ejection fraction (EF) <= 40% (24 10%), we have assessed the extension of the stress perfusion defect, and percent of reversibility (R) by quantification of stress-rest myocardial SPECT 99mTc-TF bull's eyes (2 days-protocol), lung/heart ratio (LH) calculated in the original stress SPECT images, and EF by equilibrium radionuclide ventriculography obtained at 24 h. A R value >= 8% was used to identify viable (V) patients. A total of 28 patients underwent RV and 50 only received MT. After a mean follow-up of 22.9 20 months (3-60), they were considered as coronary events (CE): cardiac death, non-fatal infarction and heart transplant. CE rate was 20.5% (16/78).. No significant differences were found in the pre-revascularization study characteristics, except a significantly higher mean R value in RV (10.6 9.5%) than in MT patients (6.4 7.8%) p: 0.03, and the main difference was that RV patients showed less CE 2/28 (7%) than the MT group 14/50 (28%) p: 0.02. The CE rate was lower in V patients who underwent RV (6%) than in V patients with MT (45%) p: 0.03, but no significant difference was obtained in non-V patients between RV (7%) and MT (16%) groups. In viable patients, the corresponding survival curves (Kaplan-Meier) showed a CE-free survival at 5 years of 79% in patients RV and of 42% in MT patients, p: 0.03, without significant difference in non-V patients.. Patients with viable myocardium by myocardial SPECT have a good prognosis after revascularization, and show higher risk of CE if they are only medically treated. Myocardial viability is an indispensable assessment in prognosis evaluation and, above all, in therapeutic decision making in dysfunctional multivessel coronary disease patients.

Topics: Adult; Aged; Cell Survival; Coronary Circulation; Coronary Disease; Death, Sudden, Cardiac; Exercise Test; Female; Follow-Up Studies; Gated Blood-Pool Imaging; Heart; Heart Transplantation; Humans; Male; Middle Aged; Myocardial Infarction; Myocardial Revascularization; Myocardium; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

Resting (99m)Tc-tetrofosmin (TF) uptake was compared with thallium ((201)Tl) rest-redistribution (R-RD) uptake in patients with previous myocardial infarction (MI) and significant coronary artery disease (CAD) to assess the ability of TF to detect viable myocardium. We studied 30 patients (21 males and nine females, mean age 53.9+/-12.5 years) with prior MI and left ventricular dysfunction who had been referred for coronary revascularization procedures. Myocardial single photon emission computed tomography (SPECT) images were obtained 1 h after injection of 750 MBq of TF. Within 1 week of the TF study, R-RD (201)Tl SPECT imaging was performed after injection of 111 MBq of (201)Tl . Quantitative analysis was performed in 21 segments. Viability was defined as the presence of tracer uptake greater than 50% of the peak activity on baseline studies or after reversibility. There was significant correlation between the quantitative regional R-RD (201)Tl activity and the resting TF activity (r=0.88, P<0.001). Quantitative analysis showed that the uptake of the two tracers was comparable in normal segments as well as in segments with fixed (201)Tl defects. In contrast, in segments with reversible (201)Tl defects, TF uptake was significantly greater than resting (201)Tl uptake, but lower than R-RD (201)Tl uptake. There were 52 segments (47% of the severely reduced segments on TF images) that showed no viability with TF, but were viable on the redistribution (201)Tl studies. We conclude that quantitative resting TF SPECT underestimates the presence of viable myocardium compared with R-RD (201)Tl imaging on the basis of using 50% of the peak activity as the viability threshold.

Topics: Adult; Aged; Biological Transport; Coronary Disease; Female; Humans; Image Processing, Computer-Assisted; Male; Middle Aged; Myocardial Infarction; Myocardial Revascularization; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Thallium Radioisotopes; Tissue Distribution; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left; Wound Healing

It has been reported that quantitative gated SPECT (QGS) has revealed post-stress dysfunction of the left ventricle (LV) 30 minutes after a stress test. The purpose of this study was to determine whether post-stress dysfunction of LV is still present one hour after an exercise stress test. The subjects comprised 152 patients (124 males and 28 females, mean age 59 +/- 10 years). Exercise stress myocardial scintigraphy was performed using a one-day, stress and rest protocol. 99mTc labeled myocardial perfusion tracer, tetrofosmin, 370 MBq was injected at the end-point of a supine ergometer stress test for stress imaging. ECG gated SPECT was carried out 1 hour after injection. Three hours later, 740 MBq to 1100 MBq of 99mTc labeled myocardial perfusion tracer was injected for rest imaging. ECG gated SPECT was again performed 1 hour after injection. We divided the subjects into four groups according to the severity score of defects on the stress image and the presence or absence of fill-in; normal (NOR, n = 59), myocardial infarct (MI, n = 65), small ischemia (S-IS, n = 13) and large ischemia (L-IS, n = 15). Post-stress dysfunction is defined according to two criteria: 1) rest LVEF--post-stress LVEF > or = 5% and 2) post-stress ESV--rest ESV > or = 5 ml. The frequency of post-stress dysfunction was 3.4%, 9.1%, 23.1% and 40% in NOR, MI, S-IS and L-IS, respectively. Post-stress LV dysfunction was found to be more frequent in the large ischemia group. In conclusion, post-stress dysfunction was present 1 hour after the stress test and was more frequent in the large ischemia group.

Topics: Aged; Electrocardiography; Exercise Test; Female; Heart; Humans; Male; Middle Aged; Myocardial Ischemia; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Time Factors; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

To investigate the role of technetium-99m (99mTc) tetrofosmin single-photon emission Computed Tomography (SPECT) associated with nitrate administration in the detection of hypoperfused but still viable myocardium in patients with chronic coronary artery disease and left ventricular (LV) dysfunction.. Twenty-two patients (mean age 54 +/- 11 years) with coronary artery disease, previous myocardial infarction and LV dysfunction (LV ejection fraction 38 +/- 13%) were examined. On different days all patients underwent 99mTc tetrofosmin (740 MBq) SPECT under control conditions at rest and after sublingual nitroglycerin administration (10 mg). Regional tetrofosmin activity was quantitatively measured in 22 myocardial segments per patient. In each segment, tracer uptake was expressed as a percentage of the region with the peak activity.. Under control conditions, 267 myocardial segments (55%) showed normal tetrofosmin uptake (> 70% of peak activity), 107 segments (22%) showed a moderate reduction (51-70%) and 110 segments (23%) a severe reduction (< or = 50%) in tracer uptake. Among the 110 segments with a severe reduction in tetrofosmin uptake, 20 (18%) showed increased tracer uptake > or = 10% of after nitrate administration (from 44 +/- 5% to 58 +/- 3%, p < 0.0001). The remaining 90 (82%) segments with a severe reduction in tetrofosmin uptake did not show any change after nitroglycerin administration (from 38 +/- 9% to 39 +/- 8%, p = ns).. In patients with chronic coronary artery disease and LV dysfunction, tetrofosmin cardiac SPECT associated with sublingual nitrate administration allows the detection of severely hypoperfused but still viable myocardium.

Topics: Adult; Aged; Chronic Disease; Heart; Hemodynamics; Humans; Male; Middle Aged; Myocardial Ischemia; Nitroglycerin; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Time Factors; Tomography, Emission-Computed, Single-Photon; Vasodilator Agents; Ventricular Dysfunction, Left

The quantitative gated SPECT (QGS) software is able to calculate LV volumes and visualize LV wall motion and perfusion throughout the cardiac cycle using an automatic edge detection algorithm of the left ventricle. We evaluated the reliability of global and regional LV function assessment derived from QGS by comparing it with the results from left ventriculo-cineangiography (LVG).. In 20 patients with left ventricular dysfunction who underwent ECG gated 99mTc-tetrofosmin SPECT, the end-diastolic volume (EDV), end-systolic volume (ESV) and ejection fraction (LVEF) were calculated. The QGS-assessed regional wall motion was determined using the cinematic display.. QGS-derived EDV, ESV and LVEF correlated well with those by LVG (p<0.001 for each). There was a good correlation between wall motion score (WMS) derived from the QGS and the LVG (r=0.40, p<0.05). In some patients with extensive myocardial infarction, there was a discrepancy in the regional wall motion results between QGS and LVG.. The ECG-gated SPECT using QGS is useful to evaluate global and regional LV functions in left ventricular dysfunction.

Topics: Adult; Aged; Algorithms; Female; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left; Ventricular Function, Left

We present a modified (non-segmental) method for quantification of regional left ventricular dysfunction using gated myocardial perfusion SPET. Gated SPET is increasingly used to obtain complementary information on local perfusion and to assess the relevance of deficits in segmental count densities (attenuation vs perfusion deficit). The non-segmental approach was motivated by a hypothetical limitation regarding the validity of commonly used methods of quantitative wall thickening (WT) analysis. These methods are all based on segmental analysis, which could cause underestimation of 'true' contractile dysfunction in perfusion defects that do not have a strict segmental distribution. SPET images gated in eight time bins 60 min after the injection of 740 MBq 99Tcm-tetrofosmin or 99Tcm-sestamibi were recorded on a triple-headed camera in 20 normal subjects and in 16 patients within 2 weeks and again 3 months after myocardial infarction. Normal limits of wall thickening, calculated from pooled wall thickening profiles obtained in normal subjects, were used to identify and quantify areas with abnormal wall thickening in patients with coronary artery disease. The method was validated against data obtained from contrast ventriculography (CVG) and tested for reproducibility. The reproducibility of the method was excellent: r = 0.98 (WTsev measure 1 = 1.03WTsev measure 2 - 0.01). The localization of wall thickening abnormalities detected by gated SPET correlated well with the localization of regions with abnormal wall motion (WM) identified by CVG. The severity of the regional myocardial dysfunction assessed by gated SPET was closely correlated with the severity of the regional myocardial dysfunction derived from CVG: r = 0.85 (WMsev = 2.55WTsev + 2.30). Furthermore, a good correlation between the total wall thickening severity score and the global left ventricular ejection fraction (LVEF) was observed early and late after myocardial infarction: r = 0.80 (WTsev = -0.4LVEF + 0.46). We conclude that quantitative analysis of regional wall thickening assessed from gated SPET myocardial perfusion scintigraphy is a reliable parameter for regional ventricular function. Categorizing wall thickening abnormalities quantitatively may be helpful in assessing small changes in regional function that may occur between sequential gated SPET images.

Topics: Adult; Aged; Case-Control Studies; Female; Gated Blood-Pool Imaging; Humans; Male; Middle Aged; Myocardial Infarction; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reproducibility of Results; Technetium Tc 99m Sestamibi; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

This study was designed to evaluate gated 99mTc-tetrofosmin SPECT for prediction of functional recovery proven by sequential MRI. 99mTc-labeled tetrofosmin is a recently introduced tracer for myocardial perfusion. However, its role for viability assessment is still under investigation.. 99mTc-tetrofosmin uptake in 19 patients with coronary artery disease and severe left ventricular dysfunction was correlated to regional wall thickening before and 4.5 +/- 0.8 mo after successful coronary artery bypass grafting, as derived from corresponding gated short-axis MRI. Preoperative wall thickening determined by gated SPECT was used as an additional parameter for prediction of functional outcome. Optimal threshold cutoffs to separate reversible from irreversible dysfunction were determined by receiver operator characteristic (ROC) analysis.. The sensitivity and specificity of regional 99mTc-tetrofosmin for prediction of functional recovery was 87% and 42%, respectively (cutoff: 50% of maximum tracer retention). The area under ROC curves for prediction of functional recovery measured 0.66 +/- 0.01. Segments with > or =50% uptake and impaired but detectable wall thickening determined by gated SPECT had a significantly higher likelihood for functional improvement compared with segments with absent wall thickening (P < 0.05). There was no difference in segments with <50% tracer retention. There was good agreement for ejection fraction measurements by MRI and gated SPECT (mean ejection fraction 32 +/- 12 versus 34 +/- 11; r = 0.71, P < 0.001).. Regional 99mTc-tetrofosmin uptake provided high sensitivity but limited specificity for prediction of functional recovery after revascularization, leading to fair overall accuracy. Wall thickening assessment derived from gated SPECT may improve the specificity of 99mTc-tetrofosmin uptake for prediction of functional recovery but not the sensitivity in low-flow areas. In addition to the assessment of global function, gated data acquisition can be helpful to improve the overall accuracy of 99mTc-tetrofosmin SPECT for prediction of functional recovery after bypass surgery.

Topics: Coronary Artery Bypass; Coronary Disease; Electrocardiography; Female; Heart; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Predictive Value of Tests; Radiopharmaceuticals; ROC Curve; Sensitivity and Specificity; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

We investigated the use of visual and quantitative technetium 99m tetrofosmin ECG-gated single-photon emission tomography (SPET) for the assessment of regional myocardial wall thickening (WT) and left ventricular (LV) ejection fraction (EF) in comparison with gated magnetic resonance imaging (MRI) in patients with a low angiographic LVEF. Gated SPET using 99mTc-labelled flow tracers offers potential for simultaneous assessment of myocardial perfusion and LV function. Few data are available on the use of visual and quantitative gated SPET in patients with low LVEF. In this study 21 patients with low angiographic LVEF (mean 37%+/-5%) were studied. Resting gated 99mTc-tetrofosmin SPET and gated MRI were performed within 48 h. WT was assessed by visual interpretation (five point score) and quantitative analysis based on count increase. There was good agreement for EF measurements by MRI and gated SPET (mean EF: 33%+/-12% vs 35%+/-11%, r = 0.86, P<0.001). Areas under receiver operator characteristic curves (AUC) for differentiation between MRI WT score points ranged from 0.60 to 0.66 for visual SPET WT analysis, from 0.59 to 0.71 for delta count increase values and from 0.46 to 0.60 for % WT, indicating substantial overlap between WT categories. Absolute agreement for visual WT between MRI and gated SPET ranged from 25% to 57% (kappa 0.03-0.25) depending on tracer uptake, and was limited in areas with moderate to severe perfusion defects (kappa 0.03-0.13). It is concluded that gated SPET provided reliable estimates of regional WT and global function in patients with low angiographic LVEF.

Topics: Coronary Angiography; Coronary Disease; Electrocardiography; Female; Heart; Humans; Image Processing, Computer-Assisted; Magnetic Resonance Imaging; Male; Middle Aged; Myocardial Contraction; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Stroke Volume; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

To determine the utility of the myocardial tracer Tc-99m-tetrofosmin in the examination of patients with left bundle branch block (LBBB) and to investigate Tc-99m-tetrofosmin uptake and retention in the myocardium, early and delayed Tc-99m-tetrofosmin SPECT was performed in 10 patients having LBBB without coronary stenosis.. After 740 MBq of Tc-99m-tetrofosmin injection in the resting state, the early and delayed SPECT imaging was done at 30 min and 180 min, respectively.. Decreased Tc-99m-tetrofosmin uptake in the septal segments was observed in 4 patients (40%) at 30 min and in 9 (90%) at 180 min. Reverse redistribution was seen in 9 of 10 patients. In patients with LBBB, the septal-to-lateral uptake ratio was lower in the delayed images than in the early images (0.80 +/- 0.09 vs. 0.89 +/- 0.09, p < 0.001). In patients with LBBB, the washout rate of Tc-99m-tetrofosmin was higher in the septal segments than in the lateral segments (28.3 +/- 4.3% vs. 22.8 +/- 3.3%, p < 0.001).. The SPECT data indicate that in LBBB without coronary stenosis, the uptake of Tc-99m-tetrofosmin is decreased in the septal wall, and that reverse redistribution occurs frequently. Our results contribute to the elucidation of both the cellular biokinetics of Tc-99m-tetrofosmin in the myocardium and the hemodynamics of the septum in LBBB, and indicate the possible clinical utility of Tc-99m-tetrofosmin.

Topics: Adult; Aged; Bundle-Branch Block; Female; Heart; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Reference Values; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

This study was undertaken to 1) compare the regional myocardial tracer distributions between rest technetium (Tc)-99m tetrofosmin and rest-redistribution thallium (Tl)-201 images in patients with coronary artery disease and left ventricular dysfunction; and 2) assess the comparative values of these agents for predicting functional recovery after revascularization.. Tc-99m tetrofosmin is a new myocardial perfusion imaging agent, but its role for detecting viable myocardium is still unclear.. Thirty-six patients with coronary artery disease and left ventricular dysfunction underwent rest Tc-99m tetrofosmin, rest-redistribution Tl-201 and gated blood pool scintigraphy. In 21 patients with successful revascularization confirmed by follow-up angiography, gated blood pool scintigraphy was repeated after revascularization. Optimal threshold cutoffs to separate reversible from irreversible dysfunction were determined by receive operating characteristic analysis.. Regional Tc-99m tetrofosimin activity highly correlated with redistribution Tl-201 activity (r = 0.93). The diagnostic performance for predicting functional recovery, as measured by the area under the receiver operating characteristic curves, measured 0.66 +/- 0.07 (mean +/- SD) for Tc-99m tetrofosmin and 0.67 +/- 0.07 for Tl-201 (p = 0.60, 96.7% power to detect difference in area of 0.10). The optimal threshold cutoffs for viability were considered to be 50% of peak activity for Tc-99m tetrofosmin and 55% of peak activity for Tl-201. The positive and negative predictive values for reversible dysfunction were, respectively, 69% and 82% for Tc-99m tetrofosmin and 69% (p = 0.99 vs. Tc-99m tetrofosmin) and 71% (p = 0.66 vs. Tc-99m tetrofosmin) by Tl-201.. The diagnostic performance of quantitative rest Tc-99m tetrofosmin imaging in predicting functional recovery after revascularization is comparable to that of rest-redistribution Tl-201.

Topics: Aged; Angioplasty, Balloon, Coronary; Case-Control Studies; Coronary Artery Bypass; Coronary Disease; Female; Gated Blood-Pool Imaging; Heart; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Predictive Value of Tests; Prospective Studies; Radiopharmaceuticals; ROC Curve; Thallium Radioisotopes; Tomography, Emission-Computed, Single-Photon; Ventricular Dysfunction, Left

A comparison was performed between technetium-99m tetrofosmin myocardial perfusion tomography at baseline and after nitrate administration, using a 2-day protocol, and rest-reinjection thallium-201 single-photon emission tomography (SPET) studies in order to assess whether nitrates enhance the detection of viable myocardium with 99mTc-tetrofosmin. Fifteen patients with coronary artery disease, previous myocardial infarction and a left ventricular ejection fraction <40% underwent 201Tl rest-injection and 99mTc-tetrofosmin baseline-postnitroglycerin (0.4 mg sublingually) SPET studies, within 48 h. Tomograms based on the three spatial planes were divided into 15 segments and regional tracer uptake was quantitatively analysed. Viability was defined as presence of tracer uptake >/=50% of peak activity on baseline studies or after reversibility. The percentage of peak activity of 99mTc-tetrofosmin at baseline correlated with that of 201Tl (r=0.82, P <0.001). On baseline 99mTc-tetrofosmin studies, 73 of the 225 segments that were analysed had <50% of peak activity. Fifteen percent of these segments showed reversibility after nitrate administration, with an increase in 99mTc-tetrofosmin uptake from 40%+/-9% to 57%+/-9% of peak activity (P=0.003). All reversible segments after nitrate administration had viability criteria on 201Tl studies, but 20 segments that were non-viable on 99mTc-tetrofosmin studies were viable on 201Tl studies. Using a threshold value of >/=40% of peak activity, only seven segments remained non-viable on 99mTc-tetrofosmin studies. Overall agreement between 99mTc-tetrofosmin with nitrates and 201Tl-reinjection regarding the presence of myocardial viability was 90%. Detection of myocardial viability with 99mTc-tetrofosmin was enhanced after nitrate administration, correlating with viability criteria observed on thallium studies.

Topics: Case-Control Studies; Coronary Disease; Female; Heart; Humans; Male; Middle Aged; Nitroglycerin; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Thallium Radioisotopes; Time Factors; Tomography, Emission-Computed, Single-Photon; Vasodilator Agents; Ventricular Dysfunction, Left

Technetium-99m-tetrofosmin uptake was compared to that of 201Tl in the setting of low flow and systolic dysfunction.. In nine open-chested dogs, a severe left anterior descending (LAD) coronary artery stenosis resulted in a 54.3% mean flow reduction and decreased left ventricular thickening from 21% +/- 1% to -3 +/- 2%. After 30 min, 37 MBq (1 mCi) of 201Tl and microspheres were injected and initial and 2-hr redistribution images acquired. Two hours later, 370 MBq (10 mCi) of 99mTc-tetrofosmin and microspheres were injected and an image was obtained. LAD: left circumflex (LCX) count ratios for both tracers and flows were calculated by well counting postmortem, and 201Tl and 99mTc-tetrofosmin defect magnitudes were determined by quantitative image analysis.. LAD:LCx flow ratios were similar during 201Tl and 99mTc-tetrofosmin injections (0.48 +/- 0.04 versus 0.49 +/- 0.05, p = n.s.). Final 201Tl activity (0.66 +/- 0.04) was significantly higher than 99mTc-tetrofosmin (0.55 +/- 0.05; p < 0.05). LAD/LCx 99mTc-tetrofosmin image defect count ratio was similar to 201Tl defect count ratio on the initial rest 201Tl scan (0.57 +/- 0.03 versus 0.56 +/- 0.02, p = ns), but significantly less than 201Tl defect count ratio at 2 hr (0.57 +/- 0.03 versus 0.65 +/- 0.02, p < 0.05).. In a low-flow model with profound systolic dysfunction, myocardial 99mTc-tetrofosmin uptake ( > 50%) reflective of viability was observed in the asynergic zone perfused by the stenotic LAD.

Topics: Animals; Coronary Circulation; Coronary Disease; Dogs; Heart; Image Processing, Computer-Assisted; Microspheres; Organophosphorus Compounds; Organotechnetium Compounds; Radionuclide Imaging; Systole; Thallium Radioisotopes; Ventricular Dysfunction, Left