Prevalence of silent myocardial ischemia in asymptomatic individuals with subclinical atherosclerosis detected by electron beam tomography

BACKGROUND: Electron beam tomography coronary calcium imaging is an evolving technique for the early detection of coronary atherosclerosis, and recent studies have established its prognostic value in asymptomatic individuals. The relationship of coronary artery calcium scores (CAC) to obstructive coronary artery disease (CAD) has been poorly studied but is clinically relevant because it determines which individuals are likely to benefit from revascularization procedures. Hence, we prospectively evaluated the prevalence of myocardial ischemia in asymptomatic patients with cardiovascular risk factors and subclinical atherosclerosis. METHODS AND RESULTS: We studied 864 asymptomatic patients with no previous CAD but with cardiovascular risk factors, referred for electron beam tomography coronary calcium imaging to our institution over an 18-month period. From this group, 220 consecutive patients (85% men; mean age, 61 +/- 9 years; age range, 31-84 years) with moderate to severe atherosclerotic disease (coronary calcium score > or =100 Agatston units) were prospectively evaluated by technetium 99m sestamibi single photon emission computed tomography (SPECT). Patients were followed up (mean follow-up, 14 months) and data regarding their subsequent clinical management recorded. Of the 220 patients, 119 had moderate atherosclerosis (CAC score of 100-400 Agatston units) and 101 had severe atherosclerosis (CAC score > or =400 Agatston units). Abnormal SPECT findings were seen in 18% of patients with moderate atherosclerosis (n = 21) and 45% of patients with severe atherosclerosis (n = 45). Increasing severity of atherosclerosis was related to increasing ischemic burden (summed difference score = 1 +/- 0.2 for CAC score of 100-400 Agatston units and 3.2 +/- 0.5 for CAC score > or =400 Agatston units). In a multivariate linear regression model incorporating risk factors, CAC was the only predictor of silent ischemia. CONCLUSION: In comparison to previously published data, we detected a higher prevalence of silent ischemia even in patients with moderate coronary atherosclerosis (18%). This may reflect the differing risk factor profile of our patient population. When coronary calcium screening is used to preselect asymptomatic patients with cardiovascular risk factors for myocardial perfusion imaging, the optimum coronary calcium score threshold will depend on the population prevalence of risk factors and asymptomatic obstructive CAD.     

Prognostic significance of silent ischemia

This study examined the prognostic predictors in 521 patients with angiographic evidence of coronary artery disease (CAD). All patients underwent exercise single-photon emission computed tomographic thallium imaging. The patients were divided into those with symptomatic ischemia defined as reversible thallium defects, S-T segment depression (or both) and angina during exercise (n= 210, group 1), and silent ischemia defined as thallium defects or ST segment depression (or both) but no angina during exercise (n = 311, group 2). During a mean follow-up of 24 ±21 months, there were 30 cardiac events (death or nonfatal myocardial infarction). The extent of CAD (2.0 ±0.8 diseased vessels in group 1 and 2.1 ±0.8 diseased vessels in group 2), the left ventricular ejection fraction, the extent of perfusion abnormality (21% ±11% in group 1 and 24% ±12% in group 2), and the peak heart rate and double product were similar in the two groups. Survival analysis showed no significant difference in the event-free survival in patients with symptomatic or silent ischemia. The 2-year event-free survival rate was 95% in group 1 and 94% in group 2 (difference not significant). The extent of perfusion abnormality and history of diabetes mellitus were the most important predictors of events. Thus the prognosis of medically treated patients with CAD is comparable in those patients with silent or symptomatic ischemia and is dependent on the extent of myocardium at risk rather than presence or absence of angina pectoris during exercise. Presented in part at the Sixty-sixth Annual Scientific Sessions of the American Heart Association, Atlanta, Ga., November 1993.     

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. Supported in part by a publication grant from GE Healthcare     

运动平板试验诊断无症状心肌缺血的临床价值

 目的 评价运动平板试验（treadmill exercise testing,TET）检出冠心病无症状心肌缺血(slient myocardial ischemia,SMI)的诊断价值。方法 对经动态心电图检查拟诊为SMI患者145例进行TET及冠状动脉造影(coronary angiography,CAG）检查,并以后者作为判定标准,计算TET诊断SMI的敏感性、特异性、准确性指数、阳性预测值及阴性预测值。结果 TET检出SMI的敏感性为89.3%,特异性为67.2%,准确性为80.0%,阳性预测值为78.9%,阴性预测值为82.0%。多支冠脉病变患者的运动平板试验阳性率与单支病变患者的对比差异无统计学意义(P>0.05)。女性运动平板试验假阳率高于男性(P <0.01)。结论 检出SMI的特异性较低,但敏感性较高,能较准确评价SMI 的缺血情况。     

心肌灌注显像联合冠状动脉钙化积分诊断冠心病的价值及最新进展

心肌灌注显像（MPI）在冠心病的诊断、危险度分层及预后评价中扮演着越来越重要的角色,冠状动脉钙化积分（CACS）可协助对冠心病患者进行进一步的危险度分层,但两者有各自的局限性和不足。将两者联合应用可以相互弥补不足,为临床提供更多的信息。行SPECT/CT心肌灌注显像时,需进行衰减矫正CT（CTAC）扫描,若采用心电门控的呼气末屏气螺旋CT扫描,则在用于MPI衰减矫正的同时又可用于CACS测定,实现一站式检查,在减少患者辐射剂量的同时又可为临床提供更多的信息。笔者综述了CACS、MPI及两者联合应用的临床价值,并对一站式采集MPI与CACS的最新进展进行了综述。     

Stress single photon emission computed tomography for detection of coronary artery disease and risk stratification of asymptomatic patients at moderate risk

Background  The American College of Cardiology Foundation/American Society of Nuclear Cardiology appropriateness criteria document assigns single photon emission computed tomography myocardial perfusion imaging (SPECT MPI) a rating of uncertain for detection and risk assessment of coronary artery disease (CAD) in asymptomatic patients at moderate risk. Methods and Results  The nuclear cardiology database was used to identify 260 asymptomatic patients (67 ± 8 years, 72% men) without known CAD who were at moderate CAD risk according to the Framingham risk score. SPECT MPI images were categorized using the summed stress score (SSS). Mean follow-up 9.9 ± 3.0 years. Abnormal SPECT MPI scans were present in 142 patients (55%). By SSS categories, SPECT scans were low-risk in 67%, intermediate-risk in 20%, and high-risk in 13% of patients. Overall survival at 10 years was 79%, significantly better than the age- and gender-matched Minnesota general population (P < 0.001). Survival was 60% for patients with high-risk scans (95% CI 45-80%), 79% with intermediate-risk scans (95% CI 69-91%), and 83% with low-risk scans (95% CI 77-88%) (P = 0.03), including 84% (95% CI 77-91%) with normal scans. Conclusions  In this retrospectively identified group of asymptomatic patients at moderate CAD risk, stress SPECT MPI was effective for the detection and risk stratification of CAD. Average annual mortality was 4.0% in patients with high-risk scans vs 1.6% in patients with normal scans.     

Mental stress-induced myocardial ischemia in coronary artery disease patients with left ventricular dysfunction

Background  Reduced left ventricular ejection fraction (LVEF) is a risk factor for poor outcomes in patients with coronary artery disease (CAD). Mental stress-induced myocardial ischemia (MSIMI) also identifies a subset of CAD patients at increased risk for future cardiovascular events. Susceptibility to MSIMI in patients with CAD and reduced LVEF is unknown. Methods and Results  We enrolled 182 patients (67 women) with a mean age of 64 years and a documented history of CAD in this study. Baseline resting ejection fraction was determined by use of technetium 99m sestamibi gated single photon emission computed tomography. Abnormal LVEF was defined as less than 45% for men and less than 50% for women (based on published norms for our software [Cedars-Sinai Medical Center]). All participants underwent mental stress testing with a public speaking task. Rest/stress myocardial perfusion single photon emission computed tomography was performed via conventional methodology. Images were visually compared for number and severity of perfusion defects by use of a scoring method from 0 to 4. A summed difference score was calculated as the difference between summed stress and rest scores. A score of greater than 3 was considered abnormal. MSIMI developed in 19% of patients with normal LVEF and 31% of those with reduced LVEF. There is no statistically significant difference between the two groups (P=.11). Conclusions  CAD patients with left ventricular dysfunction are equally susceptible to MSIMI as those with normal LVEF. This study was supported by grants HL 070265 and HL 072059 from the National Heart. Lung, and Blood Institute. This material is also the result of work supported by resources and with the use of facilities at the Department of Veterans. Affairs Medical Center, Gainesville, Fla.     

Prognostic predictors and outcomes in patients with abnormal myocardial perfusion imaging and angiographically insignificant coronary artery disease

Background. Abnormal stress myocardial perfusion imaging studies (SMPI) with angiographically insignificant coronary artery disease (ICAD) have often been labeled “false positive” scans. We evaluated the prognostic predictors and outcomes in an unselected patient population having abnormal SMPI and ICAD (study group) over a 24 month period of follow-up. Methods. Retrospective study of consecutive patients who had SMPI and subsequent coronary angiography showing ICAD within 6 months of index scan with matched control group with normal scans. Major Adverse Cardiac Events (MACE) were defined as the first occurrence of death or myocardial infarction (MI). Patients were followed up to 24 months from the time of their SMPI to identify the development of MACE. Results. One hundred and twenty five patients formed the study group and one hundred and thirty six patients formed the control group. Over a two-year follow up, approximately 13% of the study group had MACE as compared to 4.2% in the control group (P=022). Abnormal SMPI, EF<40% and chronic kidney disease (GFR<60 ml/min) were independent predictors of MACE in the study group. In multivariate analysis for MACE prediction, chronic kidney disease remained the sole independent predictor regardless of size or severity of perfusion abnormalities (P<.001). Conclusion. Patients with abnormal SMPI and ICAD have a 13% event rate of MACE over a two-year follow up. CKD seems a very important marker of a higher risk subgroup amongst such patients.     

Diagnostic accuracy of supine and prone thallium-201 stress myocardial perfusion single-photon emission computed tomography to detect coronary artery disease in inferior wall of left ventricle

OBJECTIVE: Prone thallium-201 ((201)Tl) myocardial perfusion single-photon emission computed tomography (SPECT) reduces false-positive rates when evaluating inferior wall abnormalities by minimizing diaphragmatic attenuation. The present study investigates the diagnostic validity of prone (201)Tl stress myocardial perfusion SPECT for detecting coronary artery disease in the inferior wall of the left ventricle in Japanese patients. METHODS: Of the 104 consecutive patients who underwent (201)Tl stress myocardial perfusion SPECT to diagnose coronary artery disease, we evaluated 46 who underwent image acquisition in both the supine and prone positions, and coronary angiography within 3 months thereafter. Images were acquired in the routine supine position immediately following (201)Tl (111 MBq) injection and 4 h following early acquisition. Images were acquired in the prone position only during the early phase following supine acquisition. We evaluated the SPECT images of the inferior half segments of the left ventricle using a five-point defect scoring system. According to the coronary angiographic findings, we investigated the diagnostic accuracy of stress-rest supine, stress supine, stress prone, and combined supine-prone images. Reduced uptake in the stress supine image of the combined images was considered as attenuation when uptake was normal in the prone image. RESULTS: The sensitivity of the stress-rest supine, stress supine, stress prone, and stress-combined supine-prone images was 77%, 86%, 55%, and 55%, and the specificity was 71%, 54%, 79%, and 83%, respectively. Diagnostic accuracy was the highest in stress-rest supine images. CONCLUSIONS: Prone images tended to improve the specificity of detecting coronary artery disease in the inferior wall, but not diagnostic accuracy compared with stress-rest supine images because of decreased sensitivity.     

慢性稳定型冠心病的核素心肌灌注显像临床应用进展

多项临床试验证明,核素心肌灌注显像在冠心病诊断、危险度分层、预后判断、病人处理方案等方面具有突出的作用和优越的价值。在ACC/AHA(美国心脏病学院/美国心脏学会)有关冠心病和核心脏病学指南中,心肌灌注显像的上述作用得到了充分肯定。合理应用该项技术可以提高对冠心病诊断、处理的整体水平,并使有限的医疗资源得到更合理利用,这在我国目前显得十分迫切和需要。     

平板运动试验对冠心病心肌缺血观察分析

目的:通过平板运动试验,增加心脏负荷,观察和分析冠心病心肌缺血的严重程度。方法:入选92例运动中和运动终止后有心绞痛发作13例,ST段下移41例,心绞痛伴ST段下移27例,U波倒置2例,运动后血压下降9例。结果:平板运动中心绞痛发作,ST段下移出现越早,ST段下移程度越大,持续时间越长,冠心病阳性率越高。运动性低血压,U波倒置也预示病人心功能不全。结论:提示平板运动试验可以预测冠心病心肌缺血的程度。     

Association between anxiety disorder and the extent of ischemia observed in cardiac syndrome X

Background  A possible link between the heart and brain has been reported for cardiac syndrome X. Anxiety disorder could be a pathophysiological mechanism for this cardiac chest pain. To the authors’ knowledge, a quantitative analysis correlating anxiety with the extent of ischemia has not been done. Methods and Results  In this pilot study, we evaluated 20 patients with typical chest pain and completely normal coronary angiograms. These patients were screened with the State Scale and Trait Scale of the State-Trait Anxiety Inventory (STAI). All patients underwent myocardial perfusion scintigraphic imaging. The scintigrams were scored by three experienced readers having no knowledge of the STAI screening results. Patients with a low trait anxiety had significantly less ischemic segments on the myocardial perfusion imaging than patients with a high trait anxiety (1.8 ± 1.9 vs 3.5 ± 0.6, P < .05). For state anxiety, no significant differences could be found. Conclusion  Cardiac syndrome X patients with high trait anxiety are at risk of having more ischemia.     

Use of coronary calcium scanning for predicting inducible myocardial ischemia: Influence of patients’ clinical presentation

Background  The selection of patients for cardiac stress tests is generally based on assessment of chest pain symptoms, age, gender, and risk factors, but recent data suggest that coronary artery calcium (CAC) measurements can also be used to predict inducible myocardial ischemia. However, the potential influence of clinical factors on the relationship between CAC measurements and inducible ischemia has not yet been investigated. Methods and Results  We prospectively performed CAC scanning in 648 patients undergoing exercise myocardial perfusion single photon emission computed tomography. The frequency of ischemia on myocardial perfusion single photon emission computed tomography was assessed according to CAC magnitude after dividing patients according to chest pain symptom class and Bayesian likelihood of angiographically significant coronary artery disease (ASCAD), Estimates of ASCAD likelihood and CAC scores were poorly correlated. The frequency of inducible myocardial ischemia was very low among patients with a low ASCAD likelihood if CAC scores were less than 400. By contrast, the threshold for increasing ischemia occurred at low CAC scores among patients with a high ASCAD likelihood. When characterized by chest pain classification, asymptomatic and nonanginal chest pain patients had a low frequency of ischemia if CAC scores were less than 400, whereas lower CAC scores did not exclude ischemia among typical angina or atypical angina patients. Conclusions  CAC scores predict myocardial ischemia, with a threshold score of greater than 400 among patients with a low likelihood of ASCAD and those who are asymptomatic or have nonanginal chest pain. These data appear to extend the pool of patients for whom CAC scanning may be useful in ascertaining the need for cardiac stress testing. This study was supported by a grant from the Eisner Foundation, Los Angeles. Calif.     

核素心肌显像在冠心病处理决策中的合理应用及其原理

核素心肌显像在冠心病诊断、危险度分层及预后判断方面积累了大量资料,并可据此制定冠心病的有效处理策略。在ACC/AHA(美国心脏病学会/美国心脏协会)有关冠心病和核心脏病学指南中,核素心肌显像的上述作用得到了充分肯定。合理应用该技术可以提高我们对冠心病诊断处理的整体水平,并使有限的医疗资源得到更合理利用,目前这在我国显得十分迫切和必要。     

负荷心肌灌注显像与双源CT冠脉成像诊断冠心病的对比研究

目的:通过对心肌灌注显像(MPI)与心脏双源CT(DSCT)检查结果进行对比分析,探讨两者对冠心病的临床诊断价值.方法:对38例拟诊为冠心病的患者行MPI及心脏DSCT检查;分别对MPI图像及DSCT图像进行分析处理,其中29例经冠状动脉造影(CAG)证实为冠心病.结果:DSCT显示有29例冠脉狭窄程度＞50％,其中大...     

Dobutamine Tc-99m furifosmin SPECT in detection of coronary artery disease: Evaluation of same day,rest-stress protocol

The purpose of this study was to evaluate the feasibility and diagnostic accuracy of same day rest-stress myocardial perfusion SPECT (MP SPECT) protocol by using technetium-99m (Tc-99m) furifosmin in conjunction with dobutamine stress test in subjects in whom coronary artery disease (CAD) had been proven or excluded at coronary angiography (CA). The study group consisted of 25 patients (8 female and 17 male with a mean age of 53.04±8.56 yrs) unable to perform treadmill exercise or unsuitable for pharmacologic vasodilator stress testing. Ten mCi (370 MBq) of Tc-99m furifosmin was injected intravenously at rest. Sixty min after injection, planar and SPECT images were acquired. One hour later all patients underwent dobutamine stress test. At the peak stress, 20 mCi (740 MBq) of Tc-99m furifosmin was injected. Sixty min after stress dose injection, planar and SPECT images were acquired. Rest-stress planar and SPECT data were evaluated by using visual and quantitative analysis. Heart to adjacent organ (Heart/Lung; H/Lu and Heart/Liver; H/Li) activity ratios were calculated from anterior planar images by using regions of interest (ROI). SPECT data were interpreted by using 20 segment-5 point scoring system from short axis and vertical long axis slices. The results of rest-dobutamine stress Tc-99m furifosmin MP SPECT were compared with CA results. There were statistically significant differences between H/Lu and H/Li ratios at rest and stress conditions. Heart/adjacent organ activity ratios were similar and significant statistical difference could not be found between CA positive and CA normal patients. Sensitivity, specificity and accuracy for Tc-99m furifosmin SPECT study were calculated as 90%, 80% and 84% for left anterior descending (LAD), 87%, 94% and 92% for left circumflex (LCx) and 67%, 86% and 80% for right coronary artery (RCA), respectively. Overall sensitivity, specificity and accuracy were calculated as 83%, 87% and 85%, respectively. According to the results obtained in this study, it may be concluded that same day rest-dobutamine stress Tc-99m furifosmin SPECT protocol is a feasible and accurate technique in the evaluation of CAD, especially in patients unable to perform treadmill exercise or unsuitable for pharmacologic vasodilator stress testing.     

Myocardial perfusion imaging evidence of functionally complete revascularization by minimally invasive direct coronary artery bypass in 2-vessel coronary artery disease

Background Whether patency of a second diseased vessel still impacts myocardial perfusion when complete revascularization of the left anterior descending coronary artery (LAD) territory has been achieved is currently undetermined. In patients with 2-vessel coronary artery disease and complex LAD lesions, we evaluated the impact of single LAD or integrated revascularization on single photon emission computed tomography-assessed reversible myocardial ischemia. Methods and Results Thirty-five candidates for revascularization with double-vessel disease including the LAD and a preoperative stress single photon emission computed tomography study were studied. Revascularization was performed by minimally invasive direct coronary artery bypass (MIDCAB) alone (n=15) or by an integrated procedure with second-vessel angioplasty, either soon after surgery (n=13) or at 2 months (n=7), according to the extent of reversible perfusion defects in the second vessel territory. At 1 year, the total ischemic area decreased from 9.3±5.1 to 0.8±1.5 in MIDCAB-only patients and from 8.2±4.9 to 1.6±2.9 in the integrated group (P=.87 for treatment and P<.001 for time). The ischemic area in the second vessel territory similarly decreased in both groups (P=.81 for treatment and P<.001 for time). Conclusions In 2-vessel coronary artery disease involving the LAD, MIDCAB alone achieves, in a substantial proportion of patients, functionally complete revascularization even in the nonrevascularized second vessel territory. The study was supported by grant ICS030.6 RF99/15 from the Italian National Ministry of Health.     

Dobutamine-atropine stress myocardial perfusion SPECT imaging in the diagnosis of graft stenosis after coronary artery bypass grafting

Objective  To assess the accuracy of dobutamine stress myocardial perfusion single photon emission computed tomographic imaging (SPECT) for the diagnosis of vascular stenosis after coronary artery bypass grafting (CABG). Background  Exercise thallium scintigraphy is a clinically useful method for the diagnosis of graft stenosis after CABG. Although dobutamine perfusion scintigraphy is an alternative method for the evaluation of patients with limited exercise capacity, its value in the diagnosis of vascular stenosis after CABG has not been studied. Methods  Dobutamine (up to 40 μg/kg/min)-atropine (up to 1 mg) stress test in conjunction with myocardial perfusion SPECT imaging (²⁰¹Tl or 99m technetium sestamibi [MIBI]) was performed in 71 patients (mean age 58±9 years, 57 men) with limited exercise capacity referred for evaluation of myocardial ischemia 3.7±3.5 years after CABG. Significant vascular stenosis was defined as ≥50% luminal diameter stenosis of a graft or a native nongrafted coronary artery and was predicted on the basis of reversible perfusion abnormalities. Results  Significant vascular stenosis was detected in 52 patients. Sensitivity, specificity, and accuracy of reversible perfusion defects at dobutamine SPECT for the overall diagnosis of vascular stenosis were 81%, confidence interval (CI) 72 to 90, 79%, CI 69 to 88, and 80%, CI 71 to 90, respectively. Significant vascular stenosis was detected in 73 arterial regions. Sensitivity, specificity, and accuracy of dobutamine SPECT for the diagnosis of regional vascular stenosis were 66%, CI 58 to 74, 83%, CI 76 to 89, and 74%, CI 67 to 81, respectively. Patients with multivessel stenosis had a higher number of ischemic segments (1.6±1.3 vs 1±1, P<.05) and ischemic perfusion score (3.2±2.7 vs 2.2±2.3, P<.05) than patients with single-vessel stenosis, respectively. Significant graft stenosis was detected in 67 graft regions. Sensitivity, specificity, and accuracy of dobutamine SPECT for the diagnosis of regional graft stenosis were 64%, CI 56 to 73, 85%, CI 78 to 91, and 74%, CI 66 to 82, respectively. Conclusion  Dobutamine stress myocardial perfusion SPECT imaging is a useful method for the diagnosis of significant vascular stenosis after CABG in patients with limited exercise capacity. Supported in part by the Department of Cardiology, Cairo University Hospital, Cairo, Egypt and by a grant from the NUFFIC, the Hague, the Netherlands.     

冠心病患者的肾动脉狭窄及介入治疗

目的　评价冠心病患者中肾动脉狭窄的相关因素及血管内支架术的临床价值。方法　包括 5 4例肾动脉狭窄患者和同期性别匹配的 5 7例肾动脉正常者 ,记录两组的临床特征、冠心病易患因素和血清肌酐浓度。以标准方法行冠脉和肾动脉造影及支架术。结果　肾动脉狭窄组平均年龄和血清肌酐显著增高 ,高血压和高脂血症显著增多 ,但两组的吸烟和糖尿病情况相似。肾动脉狭窄患者更易发生冠脉病变 (尤其是多支血管病变 )。 5 4例肾动脉狭窄 (单侧 5 0例 ,双侧 4例 )患者中 ,4 6例接受经皮肾动脉支架术治疗 ,各例手术成功。术后 2周 ,2 6例肾功能改善 ,2 4例高血压者血压控制良好。结论　冠心病合并肾动脉狭窄与年龄、高血压和高脂血症相关 ,血管内支架术对保护肾功能和控制高血压具重要临床作用。     

潘生丁试验在冠心病心肌显像中的意义

目的：对９９ｍ Ｔｃ － Ｍ Ｉ Ｂ Ｉ心肌显像中潘生丁试验的分析,旨在评价该法在冠心病（ Ｃ Ａ Ｄ） 诊断中的意义。方法：２１ 例正常人和８８ 例 Ｃ Ａ Ｄ 患者在９９ｍ Ｔｃ － Ｍ Ｉ Ｂ Ｉ心肌显像时进行潘生丁试验。结果：潘生丁试验诊断冠心病的灵敏度为８３ ％ ,特异性为９０ ．５ ％ ,与极量运动试验相仿。结论：本法简便易行,适应证宽,值得临床推广。