Real-time dobutamine stress myocardial perfusion echocardiography predicts outcome in the elderly.

AIMS: Although there is an increasing number of studies showing the value of perfusion imaging with real-time contrast echocardiography (RTCE) for detecting coronary artery disease (CAD), no data exist regarding the value of this technique for detecting CAD and predicting outcome in the elderly. METHODS AND RESULTS: We examined the outcome of 399 patients > or =70 years old who underwent dobutamine stress RTCE for known or suspected CAD. Myocardial perfusion imaging (MPI) was performed using low mechanical index pulse sequence schemes following intravenous small bolus injections of ultrasound contrast. Quantitative coronary angiography (QCA) was performed within 1 month of the stress test in 60 patients. Events were defined as cardiac death or non-fatal myocardial infarction (MI). Sensitivity of MPI for detecting CAD by QCA was 94% [confidence interval (CI) 91-99], specificity was 67% (CI 36-74), and accuracy was 90% (CI 82-95). During a median follow-up of 21 months, 46 events occurred (31 cardiac deaths, 15 non-fatal MI). Univariate predictors of outcome were diuretic use (P = 0.03), abnormal stress wall motion (P < 0.0001), and abnormal stress MPI (P < 0.0001). Abnormal stress MPI, however, was the most significant predictor of outcome (chi(2) 7.5; P = 0.006). CONCLUSION: Myocardial perfusion analysis during dobutamine stress RTCE provides incremental predictive value in determining the outcome of elderly patients being evaluated for the presence of CAD.     

单一影像与融合影像对比评价2型糖尿病冠状动脉病变对心肌血供影响的研究

目的:比较单一影像即核素心肌灌注显像(MPI)与融合影像即MPI/冠状动脉(冠脉)计算机断层摄影术(CT)成像(CCTA)技术,评价2型糖尿病冠脉病变对心肌血供的影响及两种影像技术的诊断效能。方法:确诊2型糖尿病且怀疑或确诊合并冠心病85例,1个月内均行常规二日法腺苷负荷/静息MPI和冠脉造影,其中38例利用单光子发射计算机断层摄影术/CT,完成同机CCTA即MPI、MPI/CCTA。MPI采用心肌17分段5级评分法,及负荷总评分(SSS)对心肌血供做定性及半定量评价;冠脉造影和CCTA按常规将冠脉病变程度分为正常;轻、中、重度;以冠脉造影、冠脉造影联合MPI为参考标准评价MPI、MPI/CCTA融合影像诊断致心肌血供异常的冠脉病变的效能。结果:85例患者,MPI提示正常/异常为22/63例;MPI的诊断效能为:敏感性、特异性、准确性、阳性预测值和阴性预测值分别为80.19%、88.59%、85.10%、83.33%和86.27%;轻度20例(24%),中度12例(14%),严重31例(36%)。38例完成同机CCTA的患者中,以冠脉造影、冠脉造影联合MPI为对照标准,单一的MPI与MPI/CCTA融合影像评价2型糖尿病冠脉病变与心肌血供关系的敏感性、特异性、准确性、阳性预测值和阴性预测值分别为74.55%与96.97%、81.36%与91.67%、78.07%与94.74%、78.85%与94.12%和77.42%与95.65%。MPI/CCTA融合影像示:正常40.35%[46/114(段/支)],中度以上狭窄冠脉59.65%[68/114(段/支)]。结论:MPI/CCTA融合影像评价2型糖尿病冠脉病变对心肌血供影响的效能明显高于单一MPI,对2型糖尿病早期冠心病诊断有重要临床价值。     

Women with high exercise tolerance and the role of myocardial perfusion imaging

BACKGROUND: Myocardial perfusion imaging (MPI) provides incremental diagnostic and prognostic information, even in patients with high exercise tolerance. HYPOTHESIS: Myocardial perfusion imaging provides significant diagnostic value, specifically in women with high exercise tolerance. METHODS: Our study population consisted of all women who underwent exercise MPI in our Department from January 1992 to June 1996 and reached at least Stage IV in the Bruce protocol. Patients were divided into those with known and those with possible coronary artery disease (CAD). All patients were followed for 3 years from the performance of MPI. RESULTS: Of 4,803 women who underwent myocardial perfusion imaging, 3,183 had exercise stressing, and of those, 311 reached at least Stage IV in the Bruce protocol. Of these 311 MPI scans, only 23 (7.4%) were abnormal (reversible, fixed, or mixed) and the remaining 288 (92.6%) were normal. Of the 82 patients with known CAD, 13 (15.8%) had an abnormal MPI, while only 10 (4.4%) of the 229 patients with possible CAD. No myocardial infarction or cardiac death occurred within 3 years; one patient with normal MPI needed revascularization. CONCLUSION: In women with high exercise tolerance, especially in those without already known CAD, the yield of MPI is very low. Women with high exercise tolerance have an excellent prognosis.     

Correlation of myocardial perfusion SPECT with invasive and computed tomography coronary angiogram

BackgroundThe consequences of atherosclerosis can be detected by multislice computed tomography (MSCT), invasive coronary angiogram (CAG) and the resultant myocardial ischaemia by myocardial perfusion single photon emission computed tomography (MPS). In this study an attempt is made to compare MSCT with MPS and also to compare the MSCT findings with that of invasive CAG in patients suspected to have coronary artery disease (CAD).Materials and methodsA total of 99 patients suspected to have CAD underwent both MSCT and MPS with ^99mTc sestamibi. The MSCT studies were classified as having no CAD, significant CAD (>50% diameter stenosis), and insignificant CAD (<50% diameter stenosis). Myocardial perfusion single photon emission computed tomography was reported as normal and reversible ischaemia. In a subgroup of 33 patient invasive CAG was done.ResultsIn 99 patients, 396 coronaries were evaluated with MSCT and MPS. Coronary artery calcium scoring (CACS) in these patient ranged from 0 to 2200. No CAD was noted in 128 (32%) coronaries but MPS was found abnormal in 9 (7%) coronaries. Insignificant CAD was noted in 169 (43%) coronaries amongst which reversible ischaemia was noted in 23 (14%). Significant CAD was noted in 99 (25%) coronaries of which only 54 (55%) were MPS positive for reversible ischaemia. The MSCT has a negative predictive value (NPV) of 97%. When MSCT was normal, MPS was almost normal, but the reverse was not true. That is when MPS was normal MSCT was not always normal but showed lesion of insignificant obstruction.In the subset of 33 patients, who underwent invasive angiogram, 132 coronaries were evaluated. Coronary angiogram showed 48 coronaries (36%) to have significant CAD (>50% diameter stenosis). Multislice computed tomography correlated well in 46 (84%) with P value of <0.001 (χ²-test) but for 9 (16%) showing overestimation due to increased CACS (>800). Myocardial perfusion single photon emission computed tomography was normal in 15 (27%) coronaries.ConclusionMyocardial perfusion single photon emission computed tomography provides functional information of the anatomical lesions and MSCT provides anatomical information. Both are two different diagnostic modalities. The MSCT has high NPV in patients with less likelihood for CAD. When compared with CAG, the correlation with MSCT was good and is useful where the calcium score is low.     

核素心肌灌注显像与多层螺旋 CT 诊断冠心病的对比分析

目的 对比分析核素心肌灌注显像(MPI)与多层螺旋CT(MSCT)对冠心病(CAD)的诊断价值,并评价两者联合诊断CAD的临床价值.方法 对43例患者(疑诊CAD 36例,确诊CAD 7例)行冠状动脉造影(CAG)、MPI和MSCT检查,且三项检查均在2个月内进行.采用半定量法对MPI结果 进行分析,SDS(总差值分)>1判定为可逆性心肌缺血,并将各心肌节段定位于其所对应的冠状动脉;参照国际上通用的目测直径法对MSCT结果 进行判定,即至少1支主要冠状动脉或其主要分支狭窄程度≥50%判定为阳性.以CAG为诊断CAD的"金标准",比较MPI与MSCT对CAD患者的诊断价值和对病变血管(狭窄程度≥50%)的检出价值.结果 MPI和MSCT对CAD患者诊断的灵敏性、特异性及准确性分别是79.17%、84.21%及81.40%和83.33%、89.47%及86.05%;MPI和MSCT对病变血管诊断的灵敏性、特异性及准确性分别是53.19%、89.02%及75.97%和70.21%、95.12%及86.05盼,两者差异均无统计学意义(P>0.05).结论 MPI和MSCT诊断CAD差异无统计学意义.两者优势互补,是筛选、诊断CAD的无创性检查手段,宜结合使用.     

Anatomic correlates of a normal perfusion scan using 64-slice computed tomographic coronary angiography

Both myocardial perfusion imaging (MPI) and multislice computed tomography (MSCT) are currently used to detect coronary artery disease (CAD). However, MSCT permits early detection of atherosclerosis while myocardial perfusion is still normal. In addition, MPI results can be normal despite the presence of high-risk CAD (left main and balanced 3-vessel CAD). In this study, the range of anatomic findings using MSCT in patients with normal MPI results was evaluated. In 180 patients presenting with chest pain, MPI (with gated single-photon emission computed tomography) and 64-slice MSCT were performed. In patients with normal MPI results, prevalences of completely normal coronary arteries, nonobstructive CAD, and obstructive CAD were determined using MSCT. The occurrence of high-risk CAD, including left main and 3-vessel disease, was also evaluated. Normal MPI and adequate MSCT findings were obtained in 97 patients (54%; 50% women; average age 58 +/- 12 years; 5% with known CAD). A total of 38 patients (39%) showed normal coronary anatomy, whereas nonsignificant and significant CAD were observed in 37 (38%) and 18 patients (19%), respectively. Importantly, only 4 patients (4%) presented with high-risk CAD using 64-slice MSCT, 2 with left main and 2 with 3-vessel disease. In conclusion, a normal MPI result can be associated with a wide range of anatomic observations and cannot exclude the presence of both nonobstructive and obstructive CAD. However, importantly, the prevalence of high-risk CAD was rare.     

Limited diagnostic yield of non-invasive coronary angiography by 16-slice multi-detector spiral computed tomography in routine patients referred for evaluation of coronary artery disease.

AIMS: Multislice spiral computed tomography (MSCT) is a promising non-invasive method to diagnose coronary artery disease (CAD). As no detailed comparative evaluation in consecutive patients referred for evaluation of CAD has been reported, this prospective study evaluating 2384 coronary segments in 149 consecutive patients was performed. METHODS AND RESULTS: The coronary artery tree was analysed in 16 segments both for coronary angiography (CA) and MSCT; a luminal narrowing > or = 50% based on visual assessment was considered significant. By MSCT, 77% of 2110 angiographically assessable segments could be evaluated, 94% per patient in proximal and 70% in distal segments (P<0.001). Sensitivity of MSCT to detect significant stenoses was 30% in all, but only 10% in peripheral segments. The main limitations were calcifications in 34% of segments and motion artefacts in 24% of patients. Overall diagnostic sensitivity for the presence of significant CAD was 86% but specificity was only 49%. CONCLUSION: When compared with invasive CA, 16-slice MSCT is of limited diagnostic value for the diagnosis of CAD in consecutive patients. Despite a clinically useful sensitivity for the overall diagnosis of significant CAD, specificity is low. Thus, relevant decisions regarding the need of and suitability for possible revascularization procedures cannot be based on MSCT findings alone.     

Do risk factors influence the diagnostic accuracy of noninvasive coronary angiography with multislice computed tomography?

BACKGROUND: Multislice computed tomography (MSCT) is a relatively new noninvasive imaging modality in the evaluation of patients with suspected coronary artery disease (CAD). Whether diagnostic accuracy is influenced by gender or risk factors for CAD is currently unknown and was evaluated in this study. METHODS AND RESULTS: In 197 patients (171 men and 26 women; mean age, 60 +/- 11 years) 16-slice MSCT was performed and compared with invasive coronary angiography at 2 different centers (Leiden and Rotterdam, The Netherlands). Diagnostic accuracy for the detection of 50% luminal narrowing or greater was calculated for all patients combined, as well as for patients with known versus suspected CAD. In addition, diagnostic accuracy was determined in men versus women and in different subsets of patients based on the presence of risk factors for CAD including hypertension, type 2 diabetes mellitus, hypercholesterolemia, and obesity. Only segments with a diameter of 2.0 mm or greater were evaluated, whereas smaller segments and stents were excluded from the analysis. Overall, a sensitivity and specificity of 99% and 86%, respectively, on a patient level were demonstrated, with corresponding positive and negative predictive values of 95% and 96%, respectively. Similar values were observed in the different subsets of patients, with no statistical differences. CONCLUSION: These findings confirm the high diagnostic accuracy of MSCT, regardless of gender or risk factors.     

Noninvasive detection of subclinical coronary atherosclerosis coupled with assessment of changes in plaque characteristics using novel invasive imaging modalities: the Integrated Biomarker and Imaging Study (IBIS).

OBJECTIVES: Our purpose was to assess noninvasive imaging in detection of subclinical atherosclerosis and to examine novel invasive modalities to describe prevalence and temporal changes in putative characteristics of "high-risk" plaques. BACKGROUND: Conventional coronary imaging cannot identify "high-risk" lesions. METHODS: Conventional (quantitative angiography and intravascular ultrasound [IVUS]) and novel imaging (IVUS-based palpography and gray scale echogenicity) were performed at baseline and 6 months later in 67 patients with diverse clinical presentations. Different imaging techniques were compared within a common segment defined by multislice computed tomography (MSCT). RESULTS: Compared with IVUS, the sensitivity, specificity, and positive and negative predictive value of MSCT for detecting significant plaque was 86%, 69%, 90%, and 61%, respectively. In coronary arteries with <50% stenosis, there were no temporal changes in luminal and plaque dimensions measured by quantitative coronary angiography or IVUS; however, a significant reduction in abnormal strain pattern was detected on palpography (density high strain spots/cm: 1.6 +/- 1.5 vs. 1.2 +/- 1.4, p = 0.0123. These changes were mainly related to significant changes in patients who presented with ST-segment elevation myocardial infarction. The assessment of plaque echogenicity showed no temporal changes. There were no correlations between circulating biomarkers and quantifiable imaging parameters. CONCLUSIONS: Mild angiographic disease is associated with large atherosclerotic plaques on MSCT. Conventional invasive coronary imaging reveals static luminal and plaque dimensions on standard medical therapy with plaque hypoechogenicity remaining unchanged over the 6-month period. By contrast, palpography measurements of strain correlate with clinical presentation and significantly decrease on standard medical therapy. Novel imaging modalities, such as palpography, might provide insights into plaque biology and might eventually serve as intermediate end points in interventional trials.     

A randomized trial of exercise treadmill ECG versus stress SPECT myocardial perfusion imaging as an initial diagnostic strategy in stable patients with chest pain and suspected CAD: cost analysis.

BACKGROUND: Exercise electrocardiography (ETT) is frequently used in patients with suspected coronary artery disease (CAD). Single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) improves diagnostic stratification. There are no randomized trials comparing ETT and MPI. We hypothesized that first-line MPI would be effective and cost-saving versus ETT. METHODS AND RESULTS: We randomized 457 outpatients with stable chest pain and suspected CAD to either treadmill electrocardiography or MPI. The post-test likelihood incorporated the pretest likelihood and the test result, with clinically driven testing. The primary endpoint was cost to diagnosis based on institutional and National Institute for Clinical Excellence costs. MPI significantly reduced the intermediate post-test likelihood of CAD (30% for ETT vs 3% for MPI, P < .0001) and further investigations (71% for ETT vs 16% for MPI, P < .0001). Despite the reduction in downstream resource utilization after MPI, mean costs were not different between the 2 initial strategies: 490.44 pounds sterling (95% confidence interval, 453.80-527.08) for ETT versus 512.41 pounds sterling (95% confidence interval, 481.41-543.41) for MPI. MPI cost was no different from ETT cost in patients with an intermediate or high pretest likelihood (P = not significant). ETT was less expensive in low-risk patients. CONCLUSIONS: In this study there was no difference in cost to diagnosis between initial ETT and MPI. In low-likelihood patients ETT was less costly, whereas there was no cost difference in intermediate- or high-likelihood patients.     

Diagnostic accuracy of dual-source multi-slice CT-coronary angiography in patients with an intermediate pretest likelihood for coronary artery disease.

AIMS: The aim of the present study was to assess the clinical performance of a dual X-ray source multi-slice CT (MSCT) with high temporal resolution to assess the coronary status in patients with an intermediate pretest likelihood for significant coronary artery disease (CAD) without using negative chronotropic pretreatment. METHODS AND RESULTS: Dual-source CT (DSCT) angiography (Siemens Definition) was performed in 90 patients with an intermediate likelihood for CAD who were referred for invasive coronary angiography. DSCT generated data sets with diagnostic image quality in 88 of the overall 90 patients. In six of seven patients with atrial fibrillation and in 46 of 48 patients with heart rates (HR)>65 b.p.m. image quality was diagnostic. In 20 of 21 patients with at least one stenosis>50% (sensitivity 95%) were correctly identified by DSCT-angiography. In 60 of 67 patients, a lesion>50% was correctly excluded (specificity 90%; positive predictive value 74%). The accuracy to detect patients with coronary stenoses>50% (sensitivity 92 vs. 100%; specificity 88 vs. 91%) was not significantly different among patients with HR>65 b.p.m. (n=46) and <65 b.p.m. The concordance of DSCT-derived stenosis quantification showed good correlation (r=0.76; P<0.001) to quantitative coronary angiography with a slight trend to overestimate the stenosis degree. CONCLUSION: DSCT is a non-invasive tool that allows to accurately rule out coronary stenoses in patients with an intermediate pretest likelihood for CAD, independent of the HR.     

Vascular endothelial dysfunction is associated with reversible myocardial perfusion defects in the absence of obstructive coronary artery disease.

BACKGROUND: The purpose of this study was to investigate whether endothelial dysfunction contributes to abnormal myocardial perfusion imaging (MPI) observed in patients without obstructive coronary artery disease (CAD). It is unclear whether reversible MPI defects detected in the absence of obstructive CAD represent underlying vascular pathology or are false-positive MPI results. Recent evidence suggests that coronary endothelial dysfunction might play a role in the pathogenesis of these defects. METHODS AND RESULTS: We prospectively recruited 36 patients with chest discomfort, reversible abnormalities on MPI, and nonobstructive or absent CAD (stenosis <50% on coronary angiography). The control group (n = 55) consisted of patients with chest discomfort and similar cardiac risk factors but with normal MPI findings. Vascular endothelial function was assessed in the brachial artery by ultrasound as the response to hyperemia and reported as percent flow-mediated dilation (FMD). Response to sublingual nitroglycerin was used as an indicator of endothelium-independent vasodilation. The patients with abnormal MPI findings and nonobstructive CAD had a significantly lower FMD (9.0% +/- 7.2%), indicating endothelial dysfunction, compared with those with similar risk factors and normal MPI findings (12% +/- 5.2%) (P = .03). Baseline brachial artery size and endothelium-independent dilation were similar between groups. On multivariate analysis, only endothelial dysfunction was predictive of reversible MPI defects. CONCLUSIONS: Patients with chest pain and reversible MPI defects but without obstructive CAD have lower FMD indicative of endothelial dysfunction, as compared with similar patients with normal MPI findings. The possibility of a causal link between reversible MPI defects and endothelial dysfunction needs further exploration.     

Non-invasive coronary computed tomographic angiography for patients with suspected coronary artery disease: the Coronary Angiography by Computed Tomography with the Use of a Submillimeter resolution (CACTUS) trial.

BACKGROUND: Non-invasive coronary angiography by multislice spiral computed tomography (MSCT) is a promising method for the diagnosis of coronary artery disease (CAD). However, the clinical role of this method has not been established for specific patient cohorts. Therefore, the objective of the current prospective, blinded study was to investigate the diagnostic value of coronary MSCT angiography in patients with an intermediate pre-test probability for having CAD when compared with invasive angiography. METHODS AND RESULTS: A total of 243 patients with an intermediate pre-test probability for having CAD were asked to undergo coronary 16- or 64-slice CT angiography before planned invasive angiography from 12 September 2003 to 13 July 2005. The primary end point was defined as the diagnostic accuracy in the detection of significant coronary stenosis (> or =50% lumen diameter reduction) on a per-patient and an 'intention-to-diagnose'-based analysis. Secondary end points comprised per-artery and per segment-based analyses as well as the comparison of diagnostic accuracy of 16- vs. 64-slice MSCT angiography. Of 243 enrolled patients, 129 and 114 patients were studied by 16- and 64-slice CT angiography, respectively. The overall sensitivity, negative predictive value, and specificity for CAD detection by MSCT were 99% (95% CI, 94-99%), 99% (95% CI, 94-99%), and 75% (95% CI, 67-82%), respectively. On a per-segment basis, the use of 64-slice CT was associated with significantly less inconclusive segments (7.4 vs. 11.3%, P < 0.01), resulting in a trend to an improved specificity (92 vs. 88%, P = 0.09). CONCLUSION: In patients with an intermediate pre-test probability for having CAD this large, prospective trial demonstrates that non-invasive coronary CT angiography is a very sensitive method for CAD detection. Furthermore, this method allows ruling out CAD very reliably and safely. Finally, 64-slice CT appears to be superior for CAD detection when compared with 16-slice CT.     

SPECT dipyridamole scintigraphy for detecting coronary artery disease in patients with isolated severe aortic stenosis.

BACKGROUND: The sensitivity and specificity of non-invasive methods--specifically single-photon emission computed tomography (SPECT) dipyridamole-thallium myocardial perfusion--for detecting coronary artery disease (CAD) in patients with severe aortic stenosis remains unclear. Occasionally, these patients present with atypical angina. Therefore, a CAD diagnosis must be excluded to prevent unnecessary cardiac catheterization. METHODS: To determine the diagnostic value of SPECT dipyridamole-thallium imaging in this population, we compared the effectiveness of the imaging procedure with that of coronary angiography by prospectively analyzing patients who underwent both procedures. Group 1 included 59 patients who were asymptomatic or had atypical angina; group 2; 51 preoperative aged-matched patients with typical angina. SPECT acquisition was performed 15 min after 0.142 mg/kg/min of dipyridamole infusion completion, and redistribution images were performed 4 h after thallium injection. Two cut-off values of luminal diameter narrowing, >50 and >70%, defined significant CAD. RESULTS: Coronary angiography with significant CAD (>50%) was present in 15 (25%) group 1 patients and in 16 (32%) group 2 patients (P=NS). The sensitivity was greater in group 2 than in group 1 (56 versus 26%; P=0.001). The specificity, positive and negative predictive value, and accuracy in the groups were similar. CAD of >70% luminal stenosis was present in 11 (19%) group 1 patients and in 12 (23%) group 2 patients (P=NS). The positive predictive value was greater in group 2 than in group 1 (75 versus 43%; P=0.001) but similar sensitivity, specificity, negative predictive value, and accuracy. The likelihood ratio for abnormal test increased in patients with CAD of >70%. CONCLUSIONS: symptoms of typical angina had significant impact on test sensitivity, positive predictive value and likelihood ratio for abnormal test. Furthermore, SPECT dipyridamole-thallium imaging was a useful non-invasive method to exclude the diagnosis of significant CAD (high specificity) in asymptomatic and symptomatic patients with isolated severe aortic stenosis.     

Positive vasodilator stress ECG with normal myocardial perfusion imaging and its correlation with coronary angiographic findings in African Americans and Hispanics

Background:

Ischemic electrocardiographic (ECG) changes during vasodilator stress testing (VST) in the presence of abnormal myocardial perfusion imaging (MPI) are uncommon and are associated with presence of multivessel coronary artery disease (CAD). However, there is a paucity of data regarding the significance of ischemic ECG changes during VST with normal MPI in general, and especially among African Americans and Hispanics.

Hypothesis:

Ischemic changes during VST with normal MPI are associated with significant CAD.

Methods:

A retrospective review was done of 2945 patients undergoing VST.

Results:

Only 20 patients (0.7%) had positive ECG changes with normal MPI. Their demographics were: 60% Hispanic, 40% African American; 85% female; mean age 63 ± 11 years; history of hypertension 80%, diabetes 50%, and dyslipidemia 75%; smokers 30%; atypical chest pain 60%, and typical chest pain 40%. Of these 20 patients, 12 patients underwent coronary angiography. All 12 had significant CAD; nine (75%) had multivessel disease and 3 (25%) had single‐vessel disease. Prevalence of clinical variables and risk factors for CAD were similar among both the groups who did and did not undergo coronary angiography.

Conclusions:

Among African Americans and Hispanics, ischemic ECG changes during VST with normal MPI are likely to be associated with significant CAD and may warrant coronary angiography to assess presence and extent of CAD. Copyright © 2010 Wiley Periodicals, Inc. The authors have no funding, financial relationships, or conflicts of interest to disclose.     

Accuracy of stress Tc-99m tetrofosmin myocardial perfusion tomography for the diagnosis and localization of coronary artery disease in women.

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

Randomized Comparison of Clinical Effectiveness of Pharmacologic SPECT and PET MPI in Symptomatic CAD Patients

ObjectivesThis study compared the clinical effectiveness of pharmacologic stress myocardial perfusion imaging (MPI) plus positron emission tomography (PET) with single-photon emission computed tomography (SPECT) in patients with known coronary artery disease (CAD) presenting with symptoms suggestive of ischemia.BackgroundAlthough PET MPI has been shown to have higher diagnostic accuracy in detecting hemodynamically significant CAD than SPECT MPI, whether this impacts downstream management has not been formally evaluated in randomized trials.MethodsThis study consisted of a single-center trial in which patients with known CAD and suspected ischemia were randomized to undergo PET or attenuation-corrected SPECT MPI between June 2009 and September 2013. Post-test management was at the discretion of the referring physician, and patients were followed for 12 months. The primary endpoint was diagnostic failure, defined as unnecessary angiography (absence of ≥50% stenosis in ≥1 vessel) or additional noninvasive testing within 60 days of the MPI. Secondary endpoints were post-test escalation of antianginal therapy, referral for angiography, coronary revascularization, and health status at 3, 6, and 12 months.ResultsA total of 322 patients with an evaluable MPI were randomized (n = 161 in each group). At baseline, 88.8% of patients were receiving aspirin therapy, 76.7% were taking beta-blockers, and 77.3% were taking statin therapy. Diagnostic failure within 60 days occurred in only 7 patients (2.2%) (3 [1.9%] in the PET group and 4 [2.5%] in the SPECT group; p = 0.70). There were no significant differences between the 2 groups in subsequent rates of coronary angiography, coronary revascularization, or health status at 3, 6, and 12 months of follow-up (all p values ≥0.20); however, when subjects were stratified by findings on MPI in a post hoc analysis, those with high-risk MPI on PET testing had higher rates of angiography and revascularization on follow-up than those who had SPECT MPI, whereas those undergoing low-risk PET studies had lower rates of both procedures than those undergoing SPECT (interaction between randomized modality 1high-risk MPI for 12-month catheterization [p = 0.001] and 12-month revascularization [p = 0.09]).ConclusionsIn this contemporary cohort of symptomatic CAD patients who were optimally medically managed, there were no discernible differences in rates of diagnostic failure at 60 days, subsequent coronary angiography, revascularization, or patient health status at 1 year between patients evaluated by pharmacologic PET compared with those evaluated by SPECT MPI. Downstream invasive testing rates with PET MPI were more consistent with high-risk features than those with SPECT MPI. (Effectiveness Study of Single Photon Emission Computed Tomography [SPECT] Versus Positron Emission Tomography [PET] Myocardial Perfusion Imaging; NCT00976053)     

Comparison between angiography and fractional flow reserve versus single-photon emission computed tomographic myocardial perfusion imaging for determining lesion significance in patients with multivessel coronary disease

We hypothesized that myocardial perfusion imaging (MPI) would fail to identify all vascular zones with the potential for myocardial ischemia in patients with multivessel coronary disease (MVD). MPI is based on the concept of relative flow reserve. The ability of these techniques to determine the significance of a particular stenosis in the setting of MVD is questionable. Fractional flow reserve (FFR) can determine the significance of individual stenoses. Thirty-six patients with disease involving 88 arteries underwent angiography, FFR, and MPI. FFR was performed using a pressure wire with hyperemia from intracoronary adenosine. Myocardial perfusion images were analyzed quantitatively and segments assigned to a specific coronary artery. The relation between FFR and perfusion was determined for each vascular zone. Of the 88 vessels, the artery was occluded (n=20) or had an abnormal FFR相似文献   

Noninvasive evaluation of the coronary arteries with multislice computed tomography in hypertensive patients

Because patients with hypertension are at increased risk for coronary artery disease, early and noninvasive identification of the disease in patients with hypertension is important. Recently, multislice computed tomography (MSCT) has been demonstrated to allow both noninvasive coronary angiography and assessment of left ventricular function. The purpose of the present study therefore was to demonstrate the feasibility of this approach in patients with hypertension with known or suspected coronary artery disease and to compare the results to invasive coronary angiography and 2-dimensional echocardiography, respectively. MSCT was performed in 31 patients with confirmed hypertension. From the MSCT images, the presence of significant coronary stenoses (>or=50% luminal narrowing) and regional wall motion abnormalities were evaluated and compared with invasive coronary angiography and 2-dimensional echocardiography. In addition, left ventricular ejection fraction was calculated from the MSCT images. A total of 243 (88%) coronary artery segments could be evaluated with MSCT. Sensitivity and specificity for the detection of significant coronary artery stenoses were 93% and 96%. On a per-patient basis, MSCT was accurate in 28 (90%) patients. Mean left ventricular ejection fraction was 46+/-14% (range, 16% to 64%). The agreement for assessing regional wall motion was 91% (kappa statistic, 0.81). In conclusion, simultaneous, noninvasive evaluation of coronary artery stenoses and left ventricular function with MSCT is accurate in patients with hypertension. This noninvasive approach may allow triage of patient treatment in terms of conservative versus invasive management.     

Aktueller Stellenwert von CT und MRT in der Koronardiagnostik

Coronary catheter angiography is the current reference standard for assessing coronary artery disease (CAD). Novel advanced cardiac imaging methods, such as CT and MRI, are opening new opportunities for the noninvasive assessment of morphologic and functional aspects of CAD and provide new options for prevention and for guiding invasive strategies. Especially in patients with low to intermediate pretest likelihood, cardiac CT has been firmly established for ruling out significant CAD (coronary CT angiography) and for evidence-based risk classification (calcium scoring). The strength of cardiac MRI lies in the functional evaluation of CAD. MRI-based myocardial perfusion and function measurements enable accurate evaluation of potential myocardial ischemia. In addition, late enhancement studies enable high resolution imaging of myocardial scar and viability.