technetium-tc-99m-tetrofosmin and Cardiovascular-Diseases

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

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

Patients with chronic kidney disease (CKD) have worse cardiovascular outcomes. The prognostic value of the new pharmacological stressor regadenoson (REG) in patients with varying levels of kidney function is not known (REG-SPECT). Furthermore, the impact of varying levels of kidney dysfunction on cardiac outcomes in patients undergoing REG-SPECT has not been defined. Our objective was to evaluate the prognostic value of regadenoson stress imaging in patients with different levels of kidney dysfunction.. We followed 1107 consecutive patients who underwent REG-SPECT for a mean duration of 1.8 ± 0.8 years. CKD was defined as estimated glomerular filtration rate (GFR) 60 mL/min/1.73 m(2). Kaplan-Meier survival analysis was performed to evaluate survival, free of major adverse cardiac events (MACE). CKD patients with GFR <60 (47% male, mean age 70 years) had a higher prevalence of cardiac risk factors and a history of coronary artery disease and were on significantly more cardiac medications (P < 0.001) than those with GFR >60. Patients with GFR <60 were significantly more likely to develop adverse cardiac outcomes including congestive heart failure (CHF) (P = 0.02), cardiac death (P < 0.001), all-cause death (P < 0.001), and MACE (P < 0.001) over the period of follow-up. Cardiac death increased with worsening levels of perfusion defects (SSS) across the entire spectrum of renal function (P < 0.001). GFR <60 was an independent predictor of MACE with a hazard ratio (HR) of 1.49 (95% CI: 1.06-2.08). The presence of transient ischaemic dilation (TID) was associated with an HR of 5.06 (95% CI: 1.43-17.90).. Renal function is a powerful risk predictor in patients undergoing REG-SPECT. REG-SPECT provides robust prognostication across the entire spectrum of renal function.

Topics: Adenosine A2 Receptor Agonists; Aged; Biomarkers; Cardiovascular Diseases; Electrocardiography; Endpoint Determination; Female; Humans; Kidney Failure, Chronic; Kidney Function Tests; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Purines; Pyrazoles; Radiopharmaceuticals; Risk Factors; Survival Rate; Tomography, Emission-Computed, Single-Photon

Topics: Adenosine A2 Receptor Agonists; Cardiovascular Diseases; Female; Humans; Kidney Failure, Chronic; Male; Organophosphorus Compounds; Organotechnetium Compounds; Purines; Pyrazoles; Tomography, Emission-Computed, Single-Photon

The active form of vitamin D (1,25(OH)(2)D) contributes to blood flow regulation in skeletal muscle. The aim of the present study was to determine whether this hormone also modulates coronary physiology, and thus whether abnormalities in its bioavailability contribute to excess cardiovascular risk in patients with disorders of mineral metabolism.. As a clinical model of the wide variability in 1,25(OH)(2)D bioavailability, we studied 23 patients (62 ± 8 years) with suspected primary hyperparathyroidism referred for myocardial perfusion imaging because of atypical chest pain and at least one cardiovascular risk factor. Dipyridamole and baseline myocardial blood flow indexes were assessed on G-SPECT imaging of (99m)Tc-tetrofosmin, with normalization of the myocardial count rate to the corresponding first-transit counts in the pulmonary artery. Coronary flow reserve (CFR) was defined as the ratio between dipyridamole and baseline myocardial blood flow indexes. In all patients, parathyroid hormone, 25-hydroxy vitamin D (25(OH)D) and 1,25(OH)(2)D serum levels were determined.. Primary hyperparathyroidism was eventually diagnosed in 15 of the 23 patients. The mean 25(OH)D concentration was relatively low (21 ± 10 ng/mL) while the concentrations of 1,25(OH)(2)D varied widely but within the normal range (mean 95 ± 61 pmol/L). No patient showed reversible perfusion defects on G-SPECT. CFR was not correlated with either the serum concentration of 25(OH)D nor that of parathyroid hormone, but was strictly correlated with the serum level of 1,25(OH)(2)D (R = 0.8, p < 0.01). Moreover, patients with a 1,25(OH)(2)D concentration below the median value (86 pmol/L) had markedly lower CFR than the other patients (1.48 ± 0.40 vs. 2.51 ± 0.63, respectively; p < 0.001).. Bioavailable 1,25(OH)(2)D modulates coronary microvascular function. This effect might contribute to the high cardiovascular risk of conditions characterized by chronic reduction in bioavailability of this hormone.

Topics: Aged; Biological Availability; Cardiovascular Diseases; Coronary Circulation; Electrocardiography; Female; Humans; Hyperparathyroidism; Male; Microcirculation; Middle Aged; Muscle, Skeletal; Myocardium; Organophosphorus Compounds; Organotechnetium Compounds; Perfusion; Pulmonary Artery; Risk; Risk Factors; Tomography, Emission-Computed, Single-Photon; Vitamin D

The aim of this study was to determine the long-term prognostic value of early poststress lung/heart ratio (LHR) of (99m)Tc-tetrofosmin radioactivity.. We studied 276 patients (aged 62.2 + or - 8.9 years, 168 men) with stress/rest (99m)Tc-tetrofosmin myocardial gated-SPECT and coronary angiography. To evaluate myocardial ischaemia, we calculated the summed stress score, summed rest score and summed difference score indices. For the eLHR calculation, an anterior image was acquired, 4-6 min after radiotracer injection at stress (eLHR was defined as mean counts per pixel in the lung region of interest divided by the mean counts per pixel in the myocardial region of interest). Cardiovascular death and nonfatal myocardial infarction were considered as hard cardiac events, and late revascularization procedures as soft cardiac events. The Cox proportional hazards model in a stepwise method was used to determine the independent predictors for hard and soft cardiac events.. During the follow-up period hard cardiac events occurred in 28 patients (10.1%) and soft cardiac events in 32 patients (11.6%). Implying multiple Cox regression analysis, eLHR was found to be a significant independent predictor for both soft and hard cardiac events. The hazard ratio (for a 0.1 unit increase) was 4.41 (95% CI 1.52-12.73, p=0.006) for soft cardiac events and 4.22 (95% CI 2.07-8.62, p<0.001) for hard cardiac events. The other significant prognostic factors were use of beta-blockers, the summed stress score and the use of nitrates for soft events, and exercise duration and the summed stress score for hard cardiac events.. Early poststress (99m)Tc-tetrofosmin LHR has an independent and powerful value in predicting hard and soft cardiac events.

Topics: Aged; Cardiac Catheterization; Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography; Cardiovascular Diseases; Comorbidity; Coronary Angiography; Coronary Disease; Exercise; Exercise Test; Female; Humans; Kaplan-Meier Estimate; Lung; Male; Middle Aged; Myocardial Infarction; Myocardial Perfusion Imaging; Myocardial Revascularization; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Proportional Hazards Models; Radiopharmaceuticals; Single-Blind Method; Smoking

This study was designed to determine the clinical risk for hard events after normal single-photon emission computed tomography (SPECT) and to identify the predictors of increased risk in asymptomatic patients with diabetes mellitus, based on a Japanese Assessment of Cardiac Events and Survival Studies by quantitative gated SPECT (J-ACCESS)-2 study.. A total of 513 consecutive asymptomatic patients who underwent stress (99m)Tc-tetrofosmin SPECT in Japan were included in this study. Based on SPECT image and QGS data, 319 had a summed stress score < or =3, a summed difference score <2 and normal cardiac function (end-systolic volume < or =60 ml, males, < or =40 ml, females; left ventricular ejection fraction > or =49%, males, > or =50%, females). Myocardial perfusion was normal in 62% of this study population. During a 3-year follow-up, there were a total of 8 cardiac major events (2.5%): 2 cases of sudden death, 5 of acute coronary syndrome, and 1 of hospitalization because of congestive heart failure. The annual major event rate was 0.8%. Subjects undergoing coronary angiography had significantly more major events than those who did not among normal SPECT subjects (P=0.01). Kaplan-Meier analysis showed that the cardiac major events rate was very low, and subjects with normal SPECT can be considered as low risk among asymptomatic patients with diabetes.. An excellent prognosis was associated with a normal SPECT in asymptomatic patients with diabetes, so these patients can be exempted from further invasive procedure.

Topics: Asian People; Cardiovascular Diseases; Coronary Angiography; Diabetes Mellitus, Type 2; Diagnostic Techniques, Cardiovascular; Female; Humans; Male; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Tomography, Emission-Computed, Single-Photon; Ventricular Function

Forearm Endothelial Function (FEF) is a marker that has been shown to discriminate patients with cardiovascular disease (CVD). FEF has been assessed using several parameters: the Rate of Uptake Ratio (RUR), EWUR (Elbow-to-Wrist Uptake Ratio) and EWRUR (Elbow-to-Wrist Relative Uptake Ratio). However, the modeling functions of FEF require more robust models. The present study was designed to compare an empirical method with quantitative modeling techniques to better estimate the physiological parameters and understand the complex dynamic processes. The fitted time activity curves of the forearms, estimating blood and muscle components, were assessed using both an empirical method and a two-compartment model. Although correlational analyses suggested a good correlation between the methods for RUR (r=.90) and EWUR (r=.79), but not EWRUR (r=.34), Altman-Bland plots found poor agreement between the methods for all 3 parameters. These results indicate that there is a large discrepancy between the empirical and computational method for FEF. Further work is needed to establish the physiological and mathematical validity of the 2 modeling methods.

Topics: Cardiovascular Diseases; Endothelium, Vascular; Female; Forearm; Humans; Kinetics; Male; Models, Cardiovascular; Organophosphorus Compounds; Organotechnetium Compounds; Radioactive Tracers; Radionuclide Imaging; Radiopharmaceuticals

We present a patient with a large hiatal hernia resulting in duodenogastric reflux that was seen as abnormal activity below and behind the heart (retrocardiac) on SPECT images and on (99m)Tc-tetrofosmin cardiac SPECT raw-data projection images. Incidental findings such as extra- and retrocardiac activity in the thorax and abdomen should be included on all comprehensive cardiac SPECT reports.

Topics: Abdomen; Aged, 80 and over; Cardiovascular Diseases; Duodenogastric Reflux; Endoscopy, Gastrointestinal; Esophagoscopy; Gated Blood-Pool Imaging; Heart; Hernia, Hiatal; Humans; Incidental Findings; Male; Organophosphorus Compounds; Organotechnetium Compounds; Prostatic Neoplasms; Radiopharmaceuticals; Smoking; Thorax; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed

The metabolic syndrome represents a constellation of risk factors caused by insulin resistance, dyslipidemia, hypertension, and obesity, resulting in elevated coronary disease risk. From a multicenter prospective registry of 7,849 patients, the relation among the metabolic syndrome, diabetes, and risk stratification with stress technetium-99m tetrofosmin single photon-emission computed tomography (SPECT) was evaluated. The percentage of stress myocardial defects was calculated as < or = 5%, 5.1% to 10%, 10.1% to 15%, and > 15%. A Cox proportional-hazards model was used to estimate cardiovascular death or myocardial infarction (n = 752). Of 7,849 patients, 42% had the metabolic syndrome. Patients with the metabolic syndrome had an 84% 2-year event-free survival rate, lower than patients with normal metabolic status (p <0.0001). In patients with the metabolic syndrome, the percentage of moderate to severely abnormal SPECT findings ranged from 11% to 44% for those with 3 to 5 risk factors for the metabolic syndrome. There was an additive relation between the number of risk factors for the metabolic syndrome and the extent and severity of abnormalities in SPECT findings (p <0.0001). Patients with 5 risk factors for the metabolic syndrome were at the greatest risk, with hazard ratios from 7.8- to 14.1-fold for mild to severely abnormal SPECT findings. For diabetic patients requiring combined oral and insulin therapy, relative risk ratios increased from 15 to 21.4 for patients with > 5% to > 15% stress myocardial perfusion defects. In conclusion, cardiovascular prognosis is affected by the degree of metabolic dysfunction, and stress-induced reductions in myocardial perfusion provide an accurate means for near-term risk stratification.

Topics: Aged; Analysis of Variance; Cardiovascular Diseases; Chi-Square Distribution; Diabetes Complications; Exercise Test; Female; Humans; Male; Metabolic Syndrome; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Proportional Hazards Models; Prospective Studies; Radiopharmaceuticals; Registries; Risk Assessment; Risk Factors; Survival Rate; Tomography, Emission-Computed, Single-Photon

To determine if there was any difference in the ability of physicians to predict prognosis with technetium 99m ((99m)Tc) sestamibi or (99m)Tc tetrofosmin in a large consecutive series of patients at high risk for coronary artery disease who underwent coronary angiography.. This study included 1,818 consecutive patients who underwent a rest and stress single photon emission computed tomographic (SPECT) examination with either (99m)Tc sestamibi (n = 915) or (99m)Tc tetrofosmin (n = 903) and cardiac catheterization. A clinical index was generated and consisted of clinical and demographic variables. Information concerning death, cardiovascular death, and nonfatal myocardial infarction was 93% complete during the 1.5-year study period. Cox proportional hazards models were generated to help determine the incremental contribution of SPECT sum stress score (SSS) and the imaging agent variable to the clinical index.. Exercise was used for stress testing in 473 (52%) patients who received (99m)Tc tetrofosmin and 519 (57%) patients who received (99m)Tc sestamibi (P =.06). Cardiovascular death or myocardial infarction occurred in 130 patients. Resulting P values for chi(2) differences between models for the end points of (a) death from any cause, (b) cardiovascular death, and (c) cardiovascular death or myocardial infarction showed that SSS combined with clinical index was a significantly better model than adjusting for only baseline characteristics (P =.001, P <.001, P =.004, respectively). Incremental addition of either (99m)Tc tetrofosmin or (99m)Tc sestamibi to those models containing SSS and the clinical index did not show further significant improvement (P =.87, P =.88, and P =.26 for death from any cause, cardiovascular death, and cardiovascular death or myocardial infarction, respectively).. This study shows that the type of clinically available (99m)Tc-labeled myocardial perfusion agents should not affect interpretation of results for risk stratification and prognostic assessment.

Topics: Adenosine; Aged; Cardiovascular Diseases; Coronary Circulation; Coronary Disease; Dipyridamole; Dobutamine; Exercise Test; Female; Humans; Male; Middle Aged; Organophosphorus Compounds; Organotechnetium Compounds; Prognosis; Proportional Hazards Models; Risk Assessment; Technetium Tc 99m Sestamibi; Tomography, Emission-Computed, Single-Photon

The lower thorax and upper abdomen are visualized during cardiac acquisition of rest Tl-201 and stress Tc-99m tetrofosmin gated SPECT. Thus, abnormal Tl-201 localization in these areas and in organs such as parts of the lungs, liver, spleen, and kidneys can be observed, including rotating raw cine data.. Other than cardiac images, the authors retrospectively reviewed Tl-201 rotating (raw data) images of 235 patients. Abnormal findings in the lungs, liver, spleen, and kidneys were identified that correlated with the patients' clinical information; radiographic findings, including computed tomography and ultrasonography of the abdomen; other scintigraphic studies; and laboratory findings.. In 53 patients, 54 abnormalities were detected. Intrathoracic abnormalities included focal areas of increased uptake, one in the right lower lung and another in the right upper lung that confirmed lung cancer, in 2 patients; diffuse uptake in both lungs in 11 patients; photopenia in the lung bases, which had resulted from pleural effusions, in 3 patients; and abnormal right liver configuration caused by elevation of the right hemidiaphragm in 1 patient. Of the intra-abdominal abnormalities, 12 patients with splenomegaly were identified. Six patients had focal areas of increased uptake in the gastric area. Nonvisualization of one kidney resulted from a congenitally absent right kidney in 1 patient, from right nephrectomy in 1 patient, from end-stage renal disease in another, and from a lower position of the left or right kidneys in 5 patients. Small and decreased uptake of both kidneys resulted from end-stage renal disease in 1 patient. Small and decreased uptake of one kidney was noted in 1 patient with renal scarring, in 1 patient with a renal stone, in 3 patients with chronic pyelonephritis, and in 5 patients with renal cyst(s).. Discernible intrathoracic and intra-abdominal abnormalities using rotating raw cine data from imaging in three-dimensional displays include diffuse or focal pulmonary uptake, pleural effusion, elevation of a hemidiaphragm, splenomegaly, increased uptake in the gastric area, renal abnormalities including absent or small kidneys, end-stage renal disease, renal scarring, renal cyst(s), and lower position of a kidney. The incidental finding of such abnormalities may prompt further clinical investigation.

Topics: Abdomen; Cardiovascular Diseases; Digestive System Diseases; Gated Blood-Pool Imaging; Humans; Kidney Diseases; Lung Diseases; Motion Pictures; Organophosphorus Compounds; Organotechnetium Compounds; Radiopharmaceuticals; Retrospective Studies; Sensitivity and Specificity; Thallium; Tomography, X-Ray Computed; Ultrasonography