Sestamibi Myocardial Perfusion Single-photon Emission Research Articles

Long-term Hemodialysis Corrects Left Ventricular Dyssynchrony in End-stage Renal Disease: A Study with Gated Technetium-99m Sestamibi Myocardial Perfusion Single-photon Emission Computed Tomography.

Left ventricular (LV) dyssynchrony is common in patients with end-stage renal disease (ESRD), and echocardiographic assessment has shown that it can be improved by a single session of hemodialysis (HD). The aim of this study was to assess the effects of chronic HD on LV dyssynchrony in patients ESRD by means of gated technetium-99m sestamibi myocardial perfusion single-photon emission computed tomography (GSPECT) with phase analysis. Twelve patients with ESRD underwent GSPECT and echocardiography before the start of long-term HD (baseline) and 3 months later. In addition, 7 control subjects matched for age and sex underwent GSPECT and echocardiography within a 2-month period. To evaluate LV dyssynchrony, both histogram bandwidth (HBW) and phase standard deviation (PSD) were determined with phase analysis of GSPECT images. The end-diastolic volume (EDV), end-systolic volume (ESV), and ejection fraction were also measured with GSPECT, and the LV mass index (LVMI) was measured with echocardiography. The LV dyssynchrony, volume, function, and mass were compared among control subjects, patients with ESRD at baseline, and patients with ESRD after 3 months of chronic HD. The LV dyssynchrony, volume, and mass at baseline were significantly greater in patients with ESRD than in control subjects (HBW, 65.5°±54.4° vs. 22.3°±7.5°, P<0.05; PSD, 21.0°±15.5° vs. 7.6°±5.5°, P<0.05; EDV, 105.7±29.2 vs. 72.3±13.9 mL, P<0.05; ESV, 44.3±22.1 vs. 20.9±10.3 mL, P<0.05; LVMI, 136.5±48.3 vs. 65.4±5.6 g/m(2), P<0.01). From baseline to the third month of chronic HD, there were significant increases in EDV (78.6±25.4 vs. 105.7±29.2 mL, P<0.01) and ESV (27.6±16.2 vs. 44.3±22.1 mL, P<0.01) and significant decreases in HBW (65.5°±54.4° vs. 31.0°±15.7°, P<0.01) and PSD (21.0°±15.5° vs. 10.0°±8.2°, P<0.01). Chronic HD decreased LV dyssynchrony and volume in patients with ESRD. Serial phase analysis of GSPECT images is a useful method of assessing the effects of long-term HD on LV dyssynchrony and volume in patients with ESRD.

Clinical usefulness of gated technetium-99m sestamibi myocardial perfusion single-photon emission computed tomography with phase analysis for the management of patients with isolated ventricular noncompaction

Gated Tc-99m sestamibi myocardial perfusion single-photon emission computed tomography (GMPS) with phase analysis provides information on myocardial perfusion, left ventricular (LV) function, and LV dyssynchrony. We present a case of isolated left ventricular noncompaction (IVNC) cardiomyopathy in which GMPS with phase analysis proved to be beneficial and reliable to monitor the long-term response to cardiac resynchronization therapy with defibrillator (CRT-D). The patient was an 84-year-old man with shortness of breath on minimal exertion (New York Heart Association class III) who had severe drug-refractory heart failure with hypotension and ventricular tachycardia. He was diagnosed with IVNC using echocardiography. At baseline, GMPS with phase analysis revealed a reduced ejection fraction (EF, 21%), large perfusion defects in the inferior and inferolateral walls, and severe LV dyssynchrony [histogram bandwidth (HBW) 120°]. Combination therapy with CRT-D and a titrated beta-blocker was initiated to induce LV reverse remodeling and reduce LV dyssynchrony. Two years after CRT-D implantation, GMPS with phase analysis showed marked improvement in LV function and LV dyssynchrony (EF 28%, HBW 36°). This case demonstrates that GMPS with phase analysis is an important and useful modality to evaluate LV function and LV dyssynchrony in IVNC patients undergoing CRT-D.<Learning objective: We experienced a rare case of heart failure with isolated left ventricular noncompaction (IVNC) treated with cardiac resynchronization therapy with defibrillator (CRT-D). We demonstrate that gated Tc-99m myocardial perfusion SPECT (GMPS) with phase analysis can simultaneously evaluate myocardial perfusion and left ventricular dyssynchrony to assess the indication and efficacy of CRT-D. This case demonstrates that GMPS with phase analysis is useful to monitor IVNC patients before and after CRT-D.>

Prospective validation of a quantitative method for differentiating ischemic versus nonischemic cardiomyopathy by technetium‐99m sestamibi myocardial perfusion single‐photon emission computed tomography

Myocardial perfusion single-photon emission computed tomography (SPECT) permits assessment of stress perfusion and resting left ventricular (LV) function. Quantitative analysis of perfusion patterns among patients with LV dysfunction offers an opportunity for developing criteria to differentiate ischemic from nonischemic cardiomyopathy. Quantitative assessment of SPECT may allow differentiation between ischemic and nonischemic cardiomyopathy. We evaluated 144 patients with LV ejection fraction < or =40%, divided into 63 patients with nonischemic and 81 with ischemic cardiomyopathy. Mean relative myocardial counts were obtained for regions drawn over defect and normal zones on rest and stress polar perfusion maps. Multivariate logistic regression analysis of significant univariate SPECT predictors of ischemic cardiomyopathy revealed that the stress defect severity ratio (SDSR) was the best predictor of ischemic cardiomyopathy (p < 0.0001). By receiver operator characteristic (ROC) curve analysis, an SDSR of < or =45% optimized prediction of ischemic cardiomyopathy (sensitivity 81%, specificity 96%). An SDSR of < or =45% occurred in 65 of 81 (80%) patients with ischemic cardiomyopathy, but in only 3 of the 63 (4%) patients with nonischemic cardiomyopathy (p < 0.0001). Applying the < or =45% SDSR threshold to a prospective group of 89 patients yielded a somewhat lower sensitivity (60%), but retained high specificity (91%) for identifying ischemic cardiomyopathy (p = NS vs. retrospective group). Presence of a severe and extensive stress perfusion defect is a hallmark of ischemic cardiomyopathy. By contrast, a mild stress perfusion defect (SDSR of >45%) is commonly present among patients with ischemic and nonischemic cardiomyopathy. An SDSR of < or =45% is a reproducible specific marker for identifying the presence of ischemic cardiomyopathy.

Usefulness of technetium-99 m sestamibi myocardial perfusion SPECT in detection of cardiovascular involvement in patients with systemic lupus erythematosus or systemic sclerosis

The main purpose of the study was to evaluate the utility of technetium-99m sestamibi myocardial perfusion single-photon emission computed tomography (Tc-99m sestamibi SPECT) in detection of cardiac involvement in systemic lupus erythematosus (SLE) or systemic sclerosis (SS) patients. Fifty SLE or SS female patients with cardiac symptom/sign such as chest discomfort and/or dyspnea and/or occasionally palpitation and 50 SLE or SS female patients without any cardiac symptom/sign were investigated using Tc-99m sestamibi SPECT during rest and stress after dipyridamole infusion. Twenty-five age- and sex-matched healthy females were also included as controls in this study. The results of Tc-99m sestamibi SPECT were classified into four types including normal, persistent perfusion defect (PD), reversible perfusion defect (RD), and reverse perfusion defect (RR). The results of Tc-99m sestamibi SPECT in the 25 healthy females were normal. Perfusion abnormalities were detected in 44/50 (88%) symptomatic SLE or SS patients. However, myocardial perfusion abnormalities were only detected in 19/50 (38%) asymptomatic SLE or SS patients ( P value<0.05 by a χ 2 test). However, for risk factor of coronary artery disease and abnormal resting EKG, the incidences were not significant between symptomatic and asymptomatic patients ( P values >0.05 by a χ 2 test). Tc-99m sestamibi SPECT is a useful noninvasive imaging modality to detect cardiac involvement in symptomatic or asymptomatic SLE or SS patients.

Prevalence and prognostic value of perfusion defects detected by stress technetium-99m sestamibi myocardial perfusion single-photon emission computed tomography in asymptomatic patients with diabetes mellitus and no known coronary artery disease

Coronary artery disease (CAD) is the leading cause of morbidity and mortality in diabetics. Early diagnosis of CAD and identification of high-risk subgroups, followed by appropriate therapy, may therefore enhance survival. This study sought to determine the value of stress myocardial perfusion single-photon emission computed tomography (SPECT) with technetium-99m sestamibi to detect perfusion defects and predict cardiac events in asymptomatic diabetics. One hundred eighty asymptomatic diabetics without known CAD who underwent 2-day stress technetium-99m sestamibi SPECT were followed up for 36 ± 18 months. End points were defined as hard (myocardial infarction or cardiac death) or total events (myocardial infarction, cardiac death, or late revascularization). Logistic regression analysis evaluated clinical variables, type of stress, exercise treadmill test (ETT), and SPECT as predictors of end points. Perfusion defects were found in 26% of patients (15% reversible, 6% mixed, and 5% fixed). Clinical or ETT variables were not associated with perfusion defect type or with hard events. However, male gender predicted total events (chi-square 3.3; p = 0.01). An abnormal SPECT significantly increased the risk of hard events (chi-square 5.4; p = 0.001) and total events (chi-square 7.4; p = 0.0001). Extensive defects determined the highest risk of total events (chi-square 18.8; p = 0.0001). Event rates increased according to SPECT: 2% of hard events per year and 5% of total events per year in patients with normal SPECT versus 9% per year and 38% per year, respectively, in those with abnormal SPECT. Importantly, a normal SPECT identified a relatively low-risk subgroup of patients. Thus, stress technetium-99m sestamibi SPECT was useful in evaluating asymptomatic diabetics for the presence of CAD, and effectively risk-stratified this population.

Automatic Quantitation of Regional Myocardial Wall Motion and Thickening From Gated Technetium-99m Sestamibi Myocardial Perfusion Single-Photon Emission Computed Tomography

Objectives. We developed an automatic quantitative algorithm for the measurement of regional myocardial wall motion and wall thickening from three-dimensional gated technetium-99m sestamibi myocardial perfusion single-photon emission computed tomographic images.Background. The algorithm measures the motion of the three-dimensional endocardial surface using a modification of the centerline method, as well as wall thickening using both geometry (gaussian fit) and partial volume (counts).Methods. The algorithm was tested using a “variable thickness” heart phantom, and the quantitative results were compared with visual segmental assessment of myocardial motion and thickening in 79 clinical patients with a wide range of ejection fractions (6% to 87%).Results. Phantom measurements of simulated motion and thickening were accurate regardless of the camera used (dual or triple detector), the angular span of reconstructed data (180° or 360°), the amount of motion (3 or 6 mm) or the amount of thickening (33%, 50% or 100%). Quantitative measurements of segmental motion and thickening in the patients were correlated with visual scores (r = 0.668, exact agreement 72.6%, kappa 0.433 and r = 0.550, exact agreement 74.7%, kappa 0.408, respectively). Significant inverse linear relations exist between the global (summed) visual motion score and the average quantitative motion, and between the global (summed) visual thickening score and the average quantitative thickening. Automatic quantitative ejection fraction measurements correlated extremely well with average quantitative motion (r = 0.929) and thickening (r = 0.959).Conclusions. Our algorithm is accurate and may be the first automatic technique for the quantitative three-dimensional assessment of regional ventricular function in cardiology.

Adenosine technetium-99m sestamibi myocardial perfusion SPECT in women: Diagnostic efficacy in detection of coronary artery disease

Objectives. This study sought to assess the diagnostic efficacy of adenosine technetium-99m (Tc-99m) sestamibi myocardial perfusion single-photon emission computed tomography (SPECT) in a consecutive series of female patients.Background. The utility of adenosine myocardial perfusion SPECT for the detection of coronary artery disease is not well defined in women because most studies have described a predominantly male population with a high prevalence of coronary artery disease.Methods. Of the 201 consecutive female patients in the study group who had undergone adenosine Tc-99m sestamibi myocardial perfusion SPECT, 130 had coronary angiography within 2 months of the nuclear test, and the other 71 had a low likelihood (<10%, mean [±SD] 5 ± 3%) of coronary artery disease. The SPECT protocol used separate acquisition of rest thallium-201 and adenosine Tc-99m sestamibi and was visually analyzed in 20 segments with a semiquantitative five-point scoring system (0 = normal; 4 = absent uptake).Results. The normaley rate in patients with a low likelihood of coronary artery disease was 93% (66 of 71). Among the catheterized group, the overall sensitivity, specificity and predictive accuracy of adenosine sestamibi SPECT for detecting coronary artery disease (⪰50% diameter stenosis) were 93% (87 of 94), 78% (28 of 36) and 88% (115 of 130), respectively. In the 103 patients without a prior myocardial infarction, the sensitivity, specificity and predictive accuracy were 91% (61 of 67), 78% (28 of 36) and 86% (89 of 103), respectively, for detecting ⪰50% diameter stenosis. Of particular interest, the sensitivity and specificity were as high in patients with nonanginal symptoms (93% and 69%, respectively) as in patients with angina (92% and 83%, respectively, p = NS). The sensitivity and specificity among patients with a relatively low (<25%), intermediate (between 25% and 75%) or high prescan likelihood of coronary artery disease (>75%) were similar: 82% and 82%, 93% and 73%, and 95% and 100%, respectively. The sensitivity and specificity for detecting individual diseased vessels (⪰50% diameter stenosis) were, respectively, 76% and 81% for the left anterior descending coronary artery, 44% and 90% for the left circumflex coronary artery and 75% and 77% for the right coronary artery.Conclusions. Adenosine Tc-99m sestamibi SPECT is an efficient protocol with high sensitivity and specificity for the detection of coronary artery disease in women irrespective of presenting symptoms or pretest likelihood of coronary artery disease and a high normaley rate. These findings are of particular clinical relevance because chest pain, anginal or otherwise, has been shown to be a frequent but a less specific marker for coronary artery disease among female patients.

Diagnostic efficacy of stress technetium 99m-labeled sestamibi myocardial perfusion single-photon emission computed tomography in detection of coronary artery disease among patients over age 80.

Because symptoms of myocardial ischemia in elderly patients are often atypical, accurate noninvasive assessment of the presence, extent, and severity of coronary artery disease (CAD) would be especially useful to avoid unnecessary catheterization or invasive intervention. This study assessed the safety and diagnostic efficacy of 99mTc-labeled sestamibi (99mTc-sestamibi) exercise and pharmacologic myocardial perfusion single-photon emission computed tomography (SPECT) with adenosine or dipyridamole in patients age 80 years or older. Stress 99mTc-sestamibi SPECT was performed in 75 consecutive patients who were 80 years old or older (range: 80 to 91 years) with suspected CAD and who underwent coronary angiography within 6 months of the nuclear study. Of these patients, 51 underwent a pharmacologic (adenosine = 42; dipyridamole = 9) stress study and 24 underwent an exercise treadmill study. A normalcy rate was derived from an additional 36 patients (ages 83 +/- 3 years) who had undergone stress 99mTc-sestamibi SPECT and who had a relatively low likelihood (< 20%) of CAD. No serious adverse events occurred during or after the exercise or the pharmacologic stress test. The overall sensitivity and specificity for detecting CAD with > or = 70% stenosis was 95% (52/55) and 75% (15/20), whereas the corresponding results were 87% (55/63) and 83% (10/12) for detecting patients with > or = 50% stenosis. The sensitivity and specificity for pharmacologic stress 99mTc-sestamibi SPECT were 95% (35/37) and 71% (10/14) for detecting > or = 70% stenosis, and 86% (37/43) and 75% (6/8) for detecting CAD with > or = 50% stenosis. The sensitivity and specificity of treadmill testing were 94% (17/18) and 83% (5/6) in detecting CAD with stenosis > or = 70% and 90% (18/20) and 100% (4/4) in detecting CAD with stenosis > or = 50%. The normalcy rate among the low likelihood patients was 83% (30/36). The accuracy of stress sestamibi testing was similar for patients with or without angina. Our findings suggest that exercise or pharmacologic myocardial perfusion SPECT with 99mTc-sestamibi is safe and diagnostically accurate for CAD detection in very elderly patients, irrespective of symptoms. Pharmacologic myocardial perfusion SPECT with adenosine or dipyridamole appears to be a valuable alternative to treadmill stress in very elderly patients incapable of performing adequate exercise.

Incremental value of prognostic testing in patients with known or suspected ischemic heart disease: A basis for optimal utilization of exercise technetium-99m sestamibi myocardial perfusion single-photon emission computed tomography

This study assessed the incremental prognostic implications of normal and equivocal exercise technetium-99m (Tc-99m) sestamibi single-photon emission computed tomography (SPECT) and sought to determine its incremental prognostic value, impact on patient management and cost implications. The prognostic implications of Tc-99m sestamibi SPECT are not well defined, and risk stratification using this test has not been explored. We studied 1,702 patients referred for exercise Tc-99m sestamibi SPECT who were followed up for a mean (+/- SD) of 20 +/- 5 months. Patients with previous percutaneous transluminal coronary angioplasty or coronary artery bypass surgery were excluded. The SPECT studies were assessed using semiquantitative visual analysis. Cardiac death and myocardial infarction were considered "hard" events, and coronary angioplasty and bypass surgery > 60 days after testing were considered "soft" events. Of the 1,702 patients studied, 1,131 had normal or equivocal scan results. A total of 10 events occurred in this group (1 cardiac death and 1 myocardial infarction [0.2% hard events]; 4 coronary angioplasty and 4 bypass surgery procedures [0.7% soft events]). The rates of hard events and referral to catheterization after SPECT were similarly low in patients with a low (< 0.15), intermediate (0.15 to 0.85) and high (> 0.85) post-exercise treadmill test (ETT) likelihood of coronary artery disease. With respect to scan type, patients with normal, probably normal or equivocal scan results had similarly low hard event rates. In the 571 patients with abnormal scan results, there were 43 hard events (7.5%) and 42 soft events (7.4%) (p < 0.001 vs. 1,131 patients with normal scan results for both). When the complete spectrum of scan responses was considered, SPECT provided incremental prognostic value in all patient subgroups analyzed. However, the nuclear scan was cost-effective only in patients with interpretable exercise ECG responses and an intermediate to high post-ETT likelihood of coronary artery disease and in those with uninterpretable exercise ECG responses and an intermediate to high pre-ETT likelihood of coronary artery disease. Normal or equivocal exercise Tc-99m sestamibi study results are associated with a benign prognosis, even in patients with a high likelihood of coronary artery disease. Although incremental prognostic value is added by nuclear testing in all patient subgroups, a testing strategy incorporating nuclear testing proved to be cost-effective only in the groups with an intermediate to high likelihood of coronary artery disease before scanning.