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

BACKGROUND: 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. HYPOTHESIS: Quantitative assessment of SPECT may allow differentiation between ischemic and nonischemic cardiomyopathy. METHODS: 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. RESULTS: 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). CONCLUSIONS: 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.     

Assessment of Myocardial Perfusion during Adenosine Stress Using Real Time Three‐Dimensional and Two‐Dimensional Myocardial Contrast Echocardiography: Comparison with Single‐Photon Emission Computed Tomography

Objectives: To evaluate diagnostic accuracy of adenosine two‐dimensional and three‐dimensional myocardial contrast echocardiography (2D‐ and 3D‐MCE) compared with single‐photon emission computed tomography (SPECT) for assessing myocardial perfusion. Methods: From January through August 2007, patients with known or suspected CAD who were referred for SPECT underwent simultaneous adenosine 2D‐MCE and 3D‐MCE (live and full volume [FV]). Perfusion and wall motion in 17 segments in the left anterior descending, left circumflex, and right coronary artery territories were analyzed. Results: We studied 30 patients: mean (SD) age, 72.6 (8.2) years; 19 (63%) men. Perfusion by SPECT was abnormal in 13 patients (43%). When comparing MCE with SPECT, sensitivity was comparable for 2D‐MCE, 92%; live 3D‐MCE, 91%; and FV 3D‐MCE, 90%. Specificity was comparable for 2D‐MCE, 75%; live 3D‐MCE, 69%; and FV 3D‐MCE, 79%. Agreement between live 3D‐MCE and 2D‐MCE was 92% (κ[SE], 0.83 [0.17]) and between FV 3D‐MCE and 2D‐MCE, 88% (κ[SE], 0.76 [0.13]). For eight patients in whom SPECT showed reversible defects, live 3D‐MCE correctly identified defects in seven (88%), whereas FV 3D‐MCE correctly identified them in five (63%) (P = 0.57). Conclusion: Myocardial perfusion assessment is feasible by 3D‐MCE with the advantage of rapid, facile acquisition and offline image manipulation. (Echocardiography 2010;27:421‐429)     

Characteristics of patients with abnormal stress technetium Tc 99m sestamibi SPECT studies without significant coronary artery diameter stenoses

BACKGROUND: Single-photon emission computed tomography (SPECT) sestamibi (MIBI) is an excellent tool for detection of coronary artery disease (CAD), preoperative risk assessment, and follow-up management after coronary revascularization. While the sensitivity of MIBI SPECT for detecting CAD has been reported to exceed 90%, the specificity ranges between 53-100%. HYPOTHESIS: The study was undertaken to assess characteristics of patients with abnormal stress technetium Tc99m sestamibi SPECT (MIBI) studies without significant coronary artery diameter stenoses (< 50%). METHODS: Between January 1999 and November 2000, 270 consecutive patients were referred for coronary angiography due to reversible MIBI uptake defects during exercise. In 41 patients (15%; 39% women, mean age 59 +/- 9 years), reversible MIBI uptake defects were assessed although coronary angiography showed no significant CAD. These patients were compared with age- and gender-matched patients with perfusion abnormalities (39% women, mean age 60 +/- 9 years), due to significant CAD (coronary artery stenosis > 50%). RESULTS: There were no significant differences between the two groups regarding body mass index, left bundle-branch block (LBBB), or method of stress test (dipyridamole in patients with LBBB or physical inactivity [n = 11] and exercise in all the others [n = 30]). Left ventricular hypertrophy (44 vs. 23%, p = 0.05) and left anterior fascicular block (LAFB) (17 vs. 0%, p = 0.005) were more common in patients with perfusion abnormalities with no significant CAD, whereas ST-segment depression during exercise (17 vs. 37% p = 0.05) and angina during exercise (15 vs. 29%, p = 0.02) were significantly less common than in patients with abnormal MIBI perfusion studies and angiographically significant CAD. Sestamibi uptake defects during exercise were significantly smaller in patients without significant CAD than in matched controls with significant CAD (p < 0.0004). CONCLUSION: Of 270 consecutive patients, 41 (15%) referred to coronary angiography due to reversible MIBI uptake defects showed coronary artery stenoses < 50%. Twenty-six (10%) of these presented angiographically normal coronary arteries. The significantly higher proportion of left ventricular hypertrophy and LAFB in patients with reversible MIBI uptake defects without significant CAD suggest microvascular disease, angiographically underestimated CAD, and conduction abnormalities as underlying mechanisms.     

Comparison of myocardial contrast echocardiography with NC100100 and (99m)Tc sestamibi SPECT for detection of resting myocardial perfusion abnormalities in patients with previous myocardial infarction

OBJECTIVE—To determine whether myocardial contrast echocardiography (MCE) following intravenous injection of perfluorocarbon microbubbles permits identification of resting myocardial perfusion abnormalities in patients who have had a previous myocardial infarction.
PATIENTS AND INTERVENTIONS—22 patients (mean (SD) age 66 (11) years) underwent MCE after intravenous injection of NC100100, a novel perfluorocarbon containing contrast agent, and resting ^99mTc sestamibi single photon emission computed tomography (SPECT). With both methods, myocardial perfusion was graded semiquantitatively as 1 = normal, 0.5 = mild defect, and 0 = severe defect.
RESULTS—Among the 203 normally contracting segments, 151 (74%) were normally perfused by SPECT and 145 (71%) by MCE. With SPECT, abnormal tracer uptake was mainly found among normally contracting segments from the inferior wall. By contrast, with MCE poor myocardial opacification was noted essentially among the normally contracting segments from the anterior and lateral walls. Of the 142 dysfunctional segments, 87 (61%) showed perfusion defects by SPECT, and 94 (66%) by MCE. With both methods, perfusion abnormalities were seen more frequently among akinetic than hypokinetic segments. MCE correctly identified 81/139 segments that exhibited a perfusion defect by SPECT (58%), and 135/206 segments that were normally perfused by SPECT (66%). Exclusion of segments with attenuation artefacts (defined as abnormal myocardial opacification or sestamibi uptake but normal contraction) by either MCE or SPECT improved both the sensitivity (76%) and the specificity (83%) of the detection of SPECT perfusion defects by MCE.
CONCLUSIONS—The data suggest that MCE allows identification of myocardial perfusion abnormalities in patients who have had a previous myocardial infarction, provided that regional wall motion is simultaneously taken into account.


Keywords: myocardial contrast echocardiography; NC100100; single photon emission computed tomography; perfusion     

Additive value of low-dose dobutamine to technetium-99m sestamibi-gated single-photon emission computed tomography for prediction of wall motion improvement in patients undergoing coronary artery bypass graft

BACKGROUND: The two most useful methods for myocardial viability assessment are perfusion imaging and dobutamine echocardiography. HYPOTHESIS: The present study investigated the additive value of a new method, dobutamine technetium 99m (99mTc)-sestamibi-gated single-photon emission computed tomography (SPECT), which combines these two modalities, to the prediction of wall motion improvement after revascularization. METHODS: Fifty-five consecutive patients with ischemic cardiomyopathy, who were referred for viability evaluation, underwent resting and dobutamine (dose, 5-10 microkg/kg/min) gated SPECT with 99mTc-sestamibi. Of these patients, 36 underwent coronary artery bypass graft (CABG) within 1 month of the study and 32 had repeat resting gated SPECT within 1 year. Global and regional wall motion, wall thickness, and perfusion were simultaneously analyzed at rest and after dobutamine using the 20-segment model; the sestamibi uptake and wall motion response to dobutamine of each segment were rated quantitatively. Based on these findings, the segments were categorized as normal, viable, or nonviable. The predictive values for wall motion improvement were assessed by perfusion, using cutoffs of 50 and 60% of sestamibi uptake, and thereafter by the addition of dobutamine response in the segments that were rated nonviable. RESULTS: Of the 1,080 myocardial segments studied, 906 (84%) had abnormal wall motion and were analyzed for viability. Concordance between perfusion and wall motion response to dobutamine was 60% with the 50% cutoff of sestamibi uptake, and increased to 65% with the 60% sestamibi cutoff (p < 0.04). The respective predictive values of wall motion improvement using the 50 and 60% cutoff points were as follows: sensitivity 93 and 70%, respectively, (p < 0.01); specificity 59 and 86% (p < 0.001), respectively; accuracy 77% for both. The addition of the wall motion response to dobutamine to the assessment of the nonviable segments by perfusion (60% cutoff) increased the sensitivity from 70 to 85% (p = 0.001) and the negative predictive value from 70 to 81% (p = 0.009); the positive predictive value remained high (86 vs. 82%). No additive value of wall motion response to dobutamine was demonstrated for nonviable segments by perfusion with a 50% cutoff. CONCLUSION: Dobutamine sestamibi-gated SPECT is a feasible method for the analysis of myocardial perfusion, function, and contractile reserve of individual myocardial segments in patients with ischemic cardiomyopathy. Viability assessment based on a threshold of 60% uptake of sestamibi, with the addition of the wall motion response to dobutamine in the nonviable segments, seems to yield better predictive values for wall motion improvement after CABG.     

Thallium-201 single-photon emission computed tomography: quantitative assessment of left ventricular perfusion and structural change in patients with chronic aortic regurgitation

BACKGROUND: Previously, perfusion defect in the left ventricle was detected by thallium-201 (201T1) single-photon emission computed tomography (SPECT) in aortic regurgitation (AR). The significance of 201T1 SPECT, however, has not been clarified. Limited information is available regarding the relationship between functional characteristics and scintigraphic findings. HYPOTHESIS: The purpose of this study was to elucidate the role of exercise 201T1 SPECT in assessing myocardial perfusion or structural change in chronic AR. We examined the correlation between 201T1 scintigraphic findings and left ventricular (LV) function parameters in 11 patients. METHODS: Defect volume ratio (DVR) in exercise 201T1 SPECT was used as a parameter of the range of abnormal thallium distribution. Left ventricular parameters were obtained by right and retrograde left cardiac catheterizations. The relationship between DVR and the parameters was analyzed. RESULTS: The DVR ranged from 1.0 to 28.3% (average 12.1 + 8.5 %). There was a significant correlation (r = 0.77, p < 0.05) between DVR and end-diastolic volume index (EDVI), a definite correlation (r = 0.66, p < 0.01) between DVR and end-systolic volume index (ESVI), and a good correlation (r = -0.77, p <0.05) between DVR and end-systolic wall stress (ESS)/ ESVI; however, no such correlation was found between DVR and ejection fraction. CONCLUSION: All patients showed abnormal defects in 201T1 accumulation scattered across the entire ventricle. A strong correlation between DVR and ESS/ESVI, an index of myocardial contractility, was a major finding of this study, suggesting a significant association between abnormal myocardial perfusion or structural alteration and reduction in myocardial contractility in chronic AR.     

Clinical decision-making and myocardial viability: current perspectives

Not all myocardium involved in a myocardial infarction is dead or irreversibly damaged. The balance between the amount of scar and live tissue, and the nature of the live tissue, determine the likelihood that contractile function will improve after revascularisation. This improvement (which defines viability) may be predicted with about 80% accuracy using several techniques. This review examines the determinants of functional recovery and how they may be integrated in making decisions regarding revascularisation.     

Evaluation of dopamine transporter density in healthy Brazilians using Tc-99m TRODAT-1 SPECT

The presynaptic dopamine transporter (DAT) modulates the uptake of dopamine by regulating its concentration in the central nervous system. We aimed to evaluate the DAT binding potential (DAT-BP) in a sample of healthy Brazilians through technetium-99 metastable TRODAT-1 single-photon emission computed tomography imaging.We selected 126 healthy individuals comprising 72 men and 54 women, aged 18 to 80 years. We conducted semi-quantitative evaluation in transaxial slices, following which we identified the regions of interest in the striatal region using the occipital lobe as a region of non-specific DAT-BP.We found a decrease in DAT-BP in healthy individuals aged over 30 years, culminating in a 42% mean reduction after 80 years. There was no difference in the decrease by age group between the right (linear regression test [R²] linear = 0.466) and left striatum (R² linear = 0.510). Women presented a higher DAT-BP than men (women: R² linear = 0.431; men: R² linear = 0.457); nonetheless, their decrease by age group was equal to that in men.Our study sheds light on important DAT-BP findings in healthy Brazilian subjects. Our results will facilitate understanding of brain illnesses that involve the dopamine system, such as neuropsychiatric disorders.     

Functional assessment of coronary artery stenosis by Doppler derived absolute and relative coronary blood flow velocity reserve in comparison with 99mTc MIBI SPECT

OBJECTIVE—To determine the relation between the relative and absolute coronary blood flow velocity reserve (CFVR) compared with the results of ^99mTc MIBI single photon emission computed tomography (SPECT).
METHODS—In 37 patients with one vessel disease, ^99mTc MIBI SPECT was performed before angioplasty, two to three weeks after angioplasty, and at six months' follow up. CFVR was measured distal to the stenosis (dCFVR) as well as in a reference coronary artery before angioplasty, immediately after angioplasty, and at late follow up. Relative CFVR (rCFVR) was calculated as the ratio between dCFVR and CFVR measured in the reference coronary artery. The optimal thresholds for reversible perfusion defects were calculated using receiver operating characteristic curves.
RESULTS—The agreement for the full range of coronary artery stenosis (n = 107, mean (SD) diameter stenosis 48 (28)%, range 0-98%) between dCFVR (cut off value 1.9) and rCFVR (cut off value 0.65) with ^99mTc MIBI SPECT was 81% and 85%, respectively. In intermediate lesions (n = 49, diameter stenosis range 30-75%) the agreement between dCFVR (cut off value 2.0) and ^99mTc MIBI SPECT was 72%, which increased to 78% using the rCFVR (cut off value 0.65).There was a strong linear relation between dCFVR and rCFVR (r = 0.93, p < 0.0001).
CONCLUSIONS—A best cut off value for dCFVR of 1.9 corresponds with a best cut off value of 0.65 for rCFVR, within the full range of coronary narrowings. Intracoronary blood flow velocity analysis could obviate the need for additional myocardial perfusion scintigraphy in the majority of patients.


Keywords: intracoronary Doppler; relative coronary blood flow velocity reserve; ^99mTc MIBI single photon emission computed tomography     

Melatonin decreases breast cancer metastasis by modulating Rho‐associated kinase protein‐1 expression

The occurrence of metastasis, an important breast cancer prognostic factor, depends on cell migration/invasion mechanisms, which can be controlled by regulatory and effector molecules such as Rho‐associated kinase protein (ROCK‐1). Increased expression of this protein promotes tumor growth and metastasis, which can be restricted by ROCK‐1 inhibitors. Melatonin has shown oncostatic, antimetastatic, and anti‐angiogenic effects and can modulate ROCK‐1 expression. Metastatic and nonmetastatic breast cancer cell lines were treated with melatonin as well as with specific ROCK‐1 inhibitor (Y27632). Cell viability, cell migration/invasion, and ROCK‐1 gene expression and protein expression were determined in vitro. In vivo lung metastasis study was performed using female athymic nude mice treated with either melatonin or Y27832 for 2 and 5 wk. The metastases were evaluated by X‐ray computed tomography and single photon emission computed tomography (SPECT) and by immunohistochemistry for ROCK‐1 and cytokeratin proteins. Melatonin and Y27632 treatments reduced cell viability and invasion/migration of both cell lines and decreased ROCK‐1 gene expression in metastatic cells and protein expression in nonmetastatic cell line. The numbers of ‘hot’ spots (lung metastasis) identified by SPECT images were significantly lower in treated groups. ROCK‐1 protein expression also was decreased in metastatic foci of treated groups. Melatonin has shown to be effective in controlling metastatic breast cancer in vitro and in vivo, not only via inhibition of the proliferation of tumor cells but also through direct antagonism of metastatic mechanism of cells rendered by ROCK‐1 inhibition. When Y27632 was used, the effects were similar to those found with melatonin treatment.     

Single-day combined evaluation of regional myocardial perfusion and function at rest and peak exercise with99mTc-MIBI in patients with coronary artery disease

^99mTc-labeled methoxy-isobutyl-isonitrile (MIBI) allows a simultaneous radionuclide assessment of regional heart function and perfusion. In this study the effectiveness of functional and perfusional images obtained with^99mTc-MIBI in the detection of coronary stenoses was compared with that of their combination.We studied 197 patients who underwent coronary angiography and a single-day radionuclide protocol including first pass angiography (multicrystal gamma camera) and single photon emission computed tomography, by means of 2 injections of^99mTc-MIBI at rest and at peak exercise. Fifteen patients had < 50% stenoses, 50 had 1-vessel, 69 2-vessel and 63 3-vessel disease, for a total of 377 pathological major coronary vessels; 129 patients had previous myocardial infarction. Functional images, perfusional tomograms and their combination showed the same sensitivity (98%) and specificity (80%) in detecting coronary patients. Regional sensitivity and specificity of the combined analysis achieved 87% and 82%, respectively, vs. 94% (p <0.005) and 60% (p <0.001) of functional images, and 88% (p=N.S.) and 74% (p <0.05) of perfusional tomograms.Thus, the combined analysis of regional functional and perfusional abnormalities increased significantly the specificity in the detection of coronary stenoses, in comparison with the separate evaluation of function and perfusion, achieving also a slightly higher diagnostic accuracy (85%, vs. 81% and 83%, respectively). The results confirm that a single-day protocol simultaneously assessing regional myocardial function and perfusion with^99mTc-MIBI represents a rapid and effective diagnostic method, that allows the physician to assess the presence and functional importance of coronary stenoses in less than 4 hours. Prof. Reale passed away January 5, 1991 Presented in part at the First Biennial Symposium of the European Working Group on Nuclear Cardiology, Rotterdam, The Netherlands, March 22–23,1991.     

硝酸甘油介入99mTc-MIBI静息态心肌断层显像估测冠心病存活心肌的临床意义

目的：探讨含服硝酸甘油（ Ｎ Ｔ Ｇ）介入９９ｍ Ｔｃ甲氧基异丁基异晴（ Ｍ Ｉ Ｂ Ｉ）心肌断层显像在心肌存活估测中的价值。方法：５４ 例冠心病患者,其中陈旧性心肌梗死（ Ｏ Ｍ Ｉ）、不稳定型心绞痛（ Ｕ Ａ）、稳定型心绞痛（ Ｓ Ａ）各１８ 例。先行静息态９９ｍ Ｔｃ Ｍ Ｉ Ｂ Ｉ心肌断层显像,４８ ｈ 后在静脉注入９９ｍ Ｔｃ Ｍ Ｉ Ｂ Ｉ前 ５ ｍ ｉｎ 舌下含服 Ｎ Ｔ Ｇ ０．５ ｍ ｇ,然后再行静息态心肌断层显像。结果：５４ 列患者静息态心肌断层显像有１６８ 个节段放射性分布异常, Ｎ Ｔ Ｇ 介入后有７１ 个节段灌注改善（４２．３％ ）。 Ｕ Ａ 组有８ 个心肌节段为不可逆性灌注缺损, Ｓ Ａ 组无不可逆性灌注缺损的心肌节段。结论：含服 Ｎ Ｔ Ｇ 能明显改善静息态９９ｍ Ｔｃ Ｍ Ｉ Ｂ Ｉ时心肌存活的检测效果,对判断病情和指导治疗有一定价值。     

Detection of occult left ventricular dysfunction in patients without prior clinical history of myocardial infarction by technetium-99m sestamibi myocardial perfusion gated single-photon emission computed tomography

BACKGROUND: In the absence of a prior history of myocardial infarction (MI), left ventricular (LV) dysfunction is commonly due to hypertension, valvular heart disease, or hibernating myocardium. HYPOTHESIS: Since technetium-99m sestamibi gated single-photon emission computed tomography (SPECT) may be used to determine both stress/rest myocardial perfusion and resting LV function, we attempted to evaluate the ability of gated SPECT imaging to detect occult LV dysfunction. METHODS: We evaluated the ability of this technique to detect occult LV dysfunction among 179 patients without history MI and angiographically documented coronary artery disease (CAD). All patients underwent both gated SPECT and cardiac catheterization within a 6-month time period. Left ventricular volume and ejection fraction (EF) values were determined according to a previously validated technique using Simpson's rule. Normal limit values for LV volumes and EF were derived from a control population of 93 patients with normal coronary angiograms. RESULTS: Based on normal limit-derived criteria, 15% of the CAD study cohort had occult LV dysfunction (> 2 standard deviations below gender-specific normal limit means for LVEF). Mean LV end-diastolic volume index (EDVi) was significantly increased (p < 0.05) and LVEF decreased (p < 0.05) in patients with triple-vessel CAD. End-diastolic volume index was also increased in the cohort of patients with both hypertension and LV hypertrophy (LVH) (p < 0.05). However, multivariate logistic regression analysis revealed that only CAD extent, but not hypertension or LVH, was a significant predictor of occult LV dysfunction (p = 0.009). CONCLUSION: Occult LV dysfunction can be detected in patients with CAD by gating technetium-99m sestamibi SPECT studies, and its presence may signify the presence of extensive CAD.     

2018 ACC/HRS/NASCI/SCAI/SCCT Expert Consensus Document on Optimal Use of Ionizing Radiation in Cardiovascular Imaging—Best Practices for Safety and Effectiveness,Part 2: Radiological Equipment Operation,Dose‐Sparing Methodologies,Patient and Medical Personnel Protection

The stimulus to create this document was the recognition that ionizing radiation‐guided cardiovascular procedures are being performed with increasing frequency, leading to greater patient radiation exposure and, potentially, to greater exposure to clinical personnel. While the clinical benefit of these procedures is substantial, there is concern about the implications of medical radiation exposure. ACC leadership concluded that it is important to provide practitioners with an educational resource that assembles and interprets the current radiation knowledge base relevant to cardiovascular procedures. By applying this knowledge base, cardiovascular practitioners will be able to select procedures optimally, and minimize radiation exposure to patients and to clinical personnel. “Optimal Use of Ionizing Radiation in Cardiovascular Imaging ‐ Best Practices for Safety and Effectiveness” is a comprehensive overview of ionizing radiation use in cardiovascular procedures and is published online. To provide the most value to our members, we divided the print version of this document into 2 focused parts. “Part I: Radiation Physics and Radiation Biology” addresses radiation physics, dosimetry and detrimental biologic effects. “Part II: Radiologic Equipment Operation, Dose‐Sparing Methodologies, Patient and Medical Personnel Protection” covers the basics of operation and radiation delivery for the 3 cardiovascular imaging modalities (x‐ray fluoroscopy, x‐ray computed tomography, and nuclear scintigraphy). For each modality, it includes the determinants of radiation exposure and techniques to minimize exposure to both patients and to medical personnel.     

Practical Approach to Evaluate Asymptomatic Coronary Artery Disease in End‐Stage Renal Disease Patients at the Initiation of Dialysis

The high prevalence of significant asymptomatic coronary artery disease (CAD) has been reported in patients with end‐stage renal disease (ESRD) at the initiation of dialysis. However, the approach to evaluate asymptomatic CAD for these patients has not been established. The aim of this study is to assess the applicability of our practical approach at the initiation of dialysis. We prospectively enrolled 182 consecutive ESRD patients who initiated dialysis. After echocardiography as primary screening, pharmacologic stress thallium‐201 scintigraphy and/or coronary angiography (CAG) were performed to diagnose CAD. The patients were classified into two groups: those with coronary artery stenosis by CAG (CAD+ group), those without coronary artery stenosis by CAG or with negative scintigraphy examination (CAD? group). Of the eligible 93 patients without the history of CAD, 22 patients were allocated to the CAD+ group (18 of 26 patients with abnormal echocardiography and 4 of 13 patients with positive scintigraphy examination) and 71 patients to the CAD? group. Patients were followed up for an average of 520 ± 304 days. The event‐free survival rate of major adverse cardiac events was significantly lower in the CAD+ group than in the CAD? group (P < 0.001). There was no cardiovascular event including major adverse cardiac events, unstable angina, coronary revascularization or stroke in the CAD? group during the first year of dialysis. Patients without CAD diagnosed by our approach had favorable clinical outcomes. Our approach may be useful for screening of occult CAD in ESRD patients at the initiation of dialysis.     

Diagnostic value of 18F-FDG PET in the assessment of myocardial viability in coronary artery disease: A comparative study with 99mTc SPECT and echocardiography

ObjectiveTo investigate the diagnostic value of 18F-fluorodeoxyglucose positron emission tomography （18F-FDG PET） in the as-sessment of myocardial viability in patients with known coronary artery disease （CAD） when compared to99mTc single photon emission computed tomography （SPECT） and echocardiography, with invasive coronary angiography as the gold standard.MethodsThirty patients with diagnosed CAD met the selection criteria, with 10 of them （9 men, mean age 59.5 ± 10.5 years） undergoing all of these imaging proce-dures consisting of SPECT and PET, echocardiography and invasive angiography. Diagnostic sensitivity of these less invasive modalities for detection of myocardial viability was compared to invasive coronary angiography. Inter- and intra-observer agreement was assessed for di-agnostic performance of SPECT and PET.ResultsOf all patients with proven CAD, 50% had triple vessel disease. Diagnostic sensitivity of SPECT, PET and echocardiography was 90%, 100% and 80% at patient-based assessment, respectively. Excellent agreement was achieved between inter-observer and intra-observer agreement of the diagnostic value of SPECT and PET in myocardial viability （k= 0.9）. Conclusion18F-FDG PET has high diagnostic value in the assessment of myocardial viability in patients with known CAD when com-pared to SPECT and echocardiography. Further studies based on a large cohort with incorporation of18F-FDG PET into patient management are warranted.