微血管性心绞痛临床特点研究

目的探讨微血管性心绞痛的临床特征。方法对30例具有典型心绞痛发作患者行常规心电图、24h动态心电图、平板运动试验检查及冠状动脉超影检查。结果静息心电图正常18例,有缺血性ST-T改变10例,冠状动脉造影正常30例,超声心动图正常28例。30例患者心绞痛发作时ST段压低,平板运动试验30例均阳性。结论微血管性心绞痛是由于冠脉微血管内皮功能障碍及微血管结构异常导致的心肌缺血。诊断需结合临床表现、心电图、平板运动试验及冠状动脉造影结果。治疗以硝酸酯类、β受体阻滞剂、尼可地尔疗效显著。临床预后良好。     

心尖肥厚型心肌病的临床诊断探讨

目的 了解心尖肥厚型心肌病的临床表现和辅助检查特点。方法 总结２９例心尖肥厚型心肌病的临床表现和心电图,超声心动图,核素心肌断层显像,运动平板心电图及冠状动脉和左室造影的特征,确定心尖肥厚型心肌病的诊断方法。结果 心电图显示以胸导为主的导联Ｒ波振幅呈Ｖ４≥Ｖ５〉Ｖ３关系增高,同时伴有Ｔ波对称性深倒置,超声心动图和核素心肌断层显像显示心尖部肌肉肥厚,２０例活动平板心电图有心肌缺血,左心室造影心尖部肌     

~(201)铊心肌显象评价特发性肥厚性主动脉瓣下狭窄患者的心绞痛症状

特发性肥厚性主动脉瓣下狭窄(IHSS)可与冠状动脉疾病并存。超声心动图可以证实IHSS的临床诊断,但评价其心绞痛症状仍存在诊断问题。由于此类病人休息时心电图常异常,运动负荷试验亦常不可靠。要确定是否有冠状动脉疾病,通常需要作选择性冠状动脉造影。最近的资料表明,~(201)铊心肌灌注显影负荷试验可用以估价由狭窄冠状动脉供给的局部心肌血流量。本文报导~(201)铊心肌灌注显象在评价IHSS伴有心绞痛而冠状动脉造影正常的病人中的意义。方法:10例经临床、血液动力学及超声心动图检查诊断为IHSS的病人,其中8例有典型劳力性心绞痛,2例有非典型胸痛。冠状动脉造影均正常。病人均进行次极量平板运动试验,除描记休息及运动心电图外,在达运动高峰时,静脉注射~(201)铊氯化     

冠状动脉造影正常,左室临界肥厚患者的运动缺血

目的 探讨冠状动脉造影正常、左室重量指数正常高限患者运动实验时心肌缺血发生情况。方法 ６４例冠状动脉造影正常患者行平静心电图、平板运动实验和超声心动图检查,测量左室舒张末期内径（ＥＤＤ）,舒张末期室间隔（ＩＶＳＴ）和左室后壁厚度（ＰＷＴ０,计算左室重量指数（ＬＶＭＩ）。根据ＬＶＭＩ将患者分为两组：左室临界肥厚组：１００〈ＬＶＭＩｔｅ≤１２５ｇ／ｍ＾２,共２０例;正常对照组：ＬＶＭＩ≤１００ｇ／ｍ＾     

药物负荷试验心肌灌注显像

心肌灌注显像被公认为诊断冠心病的最可靠、常用的无创性方法[1-2],美国的年心肌灌注显像的病例数超过了800万例,多于心电图运动试验、负荷试验超声心动图和冠状动脉造影[3].运动试验是心肌灌注显像常用的负荷试验方法,运动试验心肌灌注显像诊断冠心病的灵敏度受患者运动量的影响.     

心脏移植长期存活七例患者冠状动脉病变的观察

目的　观察 7例心脏移植长期存活患者的冠状动脉病变和心肌血液灌注情况。方法对 7例长期存活的心脏移植患者进行临床表现的询问 ,进行血液生化、标准十二导联心电图、心内膜下心肌活检、同位素心肌显像、肱动脉内皮依赖性血管舒张功能和冠状动脉造影等检查。结果　术后患者生活质量好 ;无胸闷、心悸、气促等症状 ;血液生化检查正常 ;心电图无心肌缺血改变 ;肱动脉内皮依赖性血管舒张功能正常 ;心内膜下心肌活检未见急性排异反应 ;经同位素心肌灌注显像和冠状动脉造影检查发现 3例患者存在着心肌血液灌注不足和冠状动脉病变 ,其中 1例严重者予以右冠状动脉成形和支架置入术 ,术后同位素心肌灌注显像检查示左室壁心肌放射性分布明显改善。结论　心脏移植长期存活患者易出现快速的冠状动脉病变 ;定期同位素心肌灌注显像检查 ,有助于了解心肌血液灌注情况 ;严重的局限性冠状动脉病变可应用冠状动脉成形和支架置入予以治疗。     

冠状动脉造影正常的高血压患者心肌供血分析

目的　为了解冠状动脉造影（ＣＡＧ）正常的高血压患者心肌供血情况。方法选择５２例高血压病Ｉ期或Ⅱ期患者,排除心肌梗塞,心肌病,心瓣膜病等,经ＣＡＧ证实冠状动脉无狭窄者,行心电图、超声心动图、负荷９９ＴＣ－ＭＩＢＩ心肌断层显像检查;３０例ＣＡＧ正常无上述疾病的非高血压患者做对照。结果（１）５２例高血压患者中有２５例（４８．１％）心肌断层显像显示有心肌缺血,对照组缺血者７例（２．３％）,两组差异有显著性;（２）高血压组的室间隔厚度、左房内径明显高于对照组,舒张功能明显低于对照组;（３）高血压病程、心绞痛症状、心电图ＳＴ－Ｔ改变、左室肥厚及舒张功能在高血压缺血组和非缺血组之间差异无显著性。结论高血压患者虽然ＣＡＧ正常,但核素心肌显像仍有心肌缺血存在,考虑为高血压并发微血管病变,导致冠状动脉血流储备能力（ＣＦＲ）下降所致。     

~(201)铊心肌灌注显像诊断无痛性心肌缺血的应用

为比较有心绞痛和无痛性心肌缺血病人的心肌受损范围,作者给112例经冠状动脉造影确诊的一组连续的冠心病人作了~(201)铊心肌灌注显像。检查相隔不到一个月。患者先按 Bruce 方案作平板运动试验,同时作12导联心电图。在达到运动量高峰时静脉注射3mCi~(201)铊,再继续运动1分钟。然后用SPECT(核素发射单光子断层显像)显示左室心肌灌注情况。3～5小时后再作延迟显像,观察~(201)铊再分布情况。SPECT 显示左室心尖部、中部和心底部三个平面,每个平面     

肥厚性心肌病心尖肥厚亚型的临床诊断(附28例临床报告)

目的对心尖肥厚型心肌病的辅助诊断进行探讨。方法以心电图、超声心动图、放射核素心肌断层显像、冠状动脉造影及左室造影等检查方法，诊断２８例心尖肥厚型心肌病。结果２８例心电图显示胸导联倒置的Ｔ波呈ＴＶ４＞ＴＶ５的关系；超声心动图左室心尖部（乳头肌水平以下）心肌肥厚达１２ｍｍ以上；１８例行放射核素心肌断层显像见左心室心尖部心肌肥厚；２０例左心室造影均提示心尖部心肌肥厚、冠脉造影正常，其中１１例左心室舒张末期呈“黑桃”样改变。结论标准１２导联心电图显示胸导联倒置的Ｔ波伴Ｒ波振幅增高，而不伴有高血压病史者，应高度注意心尖肥厚型心肌病的诊断。     

X综合征病人的临床特征及随访结果

运动试验阳性而冠状动脉造影正常的病人，称为X综合征或者"微血管心绞痛"。文献报道[1]，X综合征的部分病人存在左室功能下降或高血压。因此，我们对12例X综合征的病人进行了随访观察。资料和方法1．本组12例患者中，女9例，男3例，年龄33～61岁（平均45岁）。均具有典型劳力型心绞痛，运动试验阳性，冠脉造影及左室造影结果正常。均除外超声所见的左室肥厚，除外系统性高血压、心肌梗塞、肥厚性心肌病、瓣膜病、糖尿病、二尖瓣脱垂。2．治疗前均作运动试验、24小时动态心电监测、超声心动图、左室及冠脉造影门例进行右室心内膜心肌活检）…     

Vasodepressor Syncope Due to Subclinical Myocardial Ischemia

Vasodepressor Syncope. Introduction: Vasodepressor syncope is a common cause of syncope, but the initiating event that triggers the vasodepressor response remains incompletely understood. Although ischemia due to acute right coronary occlusion may precipitate hypotension and bradycardia through the Bezold-Jarisch reflex, an ischemic precipitant for the common vasodepressor faint has not been previously identified. In the present study, we present evidence for a causal relationship between myocardial ischemia and vasodepressor syncope. Methods and Results: Two patients referred for evaluation of syncope underwent upright tilt table testing with either ST segment monitoring, sestamibi scintigraphy and echocardiography during the tilt test, or coronary angiography. Both patients had positive tilt table tests during the control study. Patient 1 was documented to have reproducible ischemic ECG changes during atypical chest pressure induced by upright tilt, despite a normal coronary angiogram with ergonovine provocation. Subsequent tilt testing with simultaneous sestamibi perfusion imaging and echocardiography revealed reversible anterolateral hypoperfusion corresponding with anterolateral hypokinesis during upright tilt that preceded syncope. Ischemic ECG changes during incremental rapid atrial pacing further suggested ischemia on the basis of microvascular disease. Follow-up tilt testing on verapamil was negative. Patient 2 developed ischemic ECG changes during the recovery phase of an exercise stress test, which was followed by a vasodepressor response and frank syncope. Coronary angiography revealed a 90% distal right coronary artery stenosis that was successfully dilated, after which follow-up tilt table testing off all other medication was negative. Conclusions: These two cases illustrate a previously unrecognized causality between myocardial ischemia and clinical vasodepressor syncope, and demonstrate that subtle manifestations of myocardial ischemia, associated with either atypical angina or silent ischemia, can provoke syncope.     

Unusual congenital coronary anomaly and myocardial ischaemia

Angiography was used to diagnose a rare congenital coronary anomaly with myocardial ischaemia in a woman with typical angina. All three coronary arteries arose from a solitary coronary ostium in the right aortic sinus; the left anterior descending coronary artery followed a septal course, the circumflex coronary artery ran behind the ascending aorta, and the right coronary artery followed a normal course. No significant coronary lumen narrowing was found. Transoesophageal echocardiography confirmed the anomalous origin and course of the aberrant coronary arteries. An exercise test reproduced angina, and ECG changes and myocardial perfusion study showed an anterior reversible defect. In contrast to previous reports, myocardial ischaemia was associated with the septal (intramuscular) course of the left anterior descending coronary artery; there was no other significant coronary artery disease.


Keywords: congenital heart defects; myocardial ischaemia; angiography; echocardiography     

Idiopathic hypertrophic subaortic stenosis: evaluation of anginal symptoms with thallium-201 myocardial imaging.

The evaluation of angina pectoris in patients with idiopathic hypertrophic subaortic stenosis is difficult in those in the age group prone to coronary artery disease. Ten patients with angina pectoris, normal coronary angiograms and idiopathic hypertrophic subaortic stenosis were studied with thallium-201 myocardial imaging performed in conjunction with submaximal treadmill exercise testing. The resting electrocardiogram demonstrated left ventricular hypertrophy with S-T segment abnormalities in seven patients, thereby vitiating the further increase in S-T segment abnormalities that developed in these patients during exercise or in the postexercise period. Of the three patients with a normal resting electrocardiogram, one had significant exercise-induced S-T segment depression. Thallium-201 myocardial imaging revealed no significant perfusion defects in 9 of the 10 patients (90 percent). In one patient with severe left ventricular hypertrophy significant perfusion defects developed after exercise that were not present at rest. Stress thallium-201 myocardial perfusion imaging is a useful noninvasive technique that assists in ruling out the presence of significant coronary artery disease in patients with idiopathic hypertrophic subaortic stenosis.     

Non-invasive characterization of cardiac microvascular disease by nuclear medicine using single-photon emission tomography

In about 10 to 30% of patients with typical angina undergoing coronary angiography for suspicion of stenotic coronary artery disease angiographically normal coronary arteries are found. Kemp et al. in 1973 coined the term syndrome X to describe this entity. In a substantial portion of these patients pathologic findings in myocardial scintigraphy are present. Sensitivity and specificity of thallium-201 exercise imaging by visual analysis of images in the presence of significant coronary stenosis is 84 and 88%, respectively. Several investigators have reported abnormal results in radionuclide exercise tests in patients with angiographically normal coronary arteries. Some of these results can be explained by myocardial bridging, vasospasm, left or right bundle branch block, hypertrophic cardiomyopathy, or absorption artifacts. In the majority of cases, however, these abnormalities are not sufficient to explain the scintigraphic findings. Formerly often claimed "false positive", recent studies suggest that endothelial dysfunction might be the reason for the observed perfusion defects. When comparing patients with angiographically unobstructed coronary arteries with and without perfusion defects in stress myocardial perfusion imaging, patients with pathological results show a significantly lower increase of coronary flow after intracoronary injection of the endothelial-dependent vasodilator acetylcholine. Endothelial-independent vasodilation, however, is not impaired in these patients. In addition, intracoronary Doppler measurements reveal that perfusion defects in myocardial scintigraphy only occur if coronary blood flow in this perfusion area is significantly reduced. These results suggest that regional endothelial dysfunction may cause hypoperfusion in myocardial perfusion imaging and underline the important role of the microcirculation in the distribution of radiotracers. Another striking scintigraphic pattern in patients with microvascular angina is the high incidence of reverse redistribution. These perfusion defects, apparent in images obtained 4 hours after exercise stress testing, often cannot be assigned to the perfusion territory of one of the major epicardial vessels. This results in a marked inhomogeneous radionuclide distribution pattern in resting images. The inhomogeneity is associated with a significant reduced resting coronary flow velocity in these patients. As histologically confirmed microvessel disease is often accompanied by slow-flow phenomenon reflecting decreased resting flow velocity, the results suggest that the inhomogeneous perfusion pattern is caused by microvascular dysfunction. Furthermore, the heterogeneity of nuclide distribution supports the hypothesis that endothelial function is not homogeneous in the entire myocardial microcirculation, but varies considerably. In conclusion, microvascular dysfunction by itself seems to cause regional myocardial hypoperfusion, as documented by myocardial scintigraphy. When interpreting pathological scintigraphic results in patients without significant epicardial stenosis, true blood flow and myocardial perfusion abnormalities must be assumed.     

Clinical Indications for Thallium-201 Myocardial Perfusion Scanning*

Abstract: Clinical indications for Thallium-201 myocardial perfusion scanning. R. F. Dunn and D. T. Kelly, Aust. N.Z. J. Med., 1982, 12, pp. 294–301. Thallium-201 myocardial perfusion scanning can assess regional myocardial perfusion noninvasive^. As it is both time-consuming and expensive its use should be restricted to specific diagnostic problems. The clinical indications in known or suspected coronary artery disease are reviewed. In suspected coronary artery disease thallium scanning is most useful in patients with chest pain when the exercise ECG is uninterpretable, in men with probable angina but a negative exercise ECG, or conversely a positive exercise ECG without typical angina, and in women with probable angina and either a positive or a negative exercise ECG. In known coronary artery disease, thallium scanning may help determine the functional significance of a coronary obstruction found at angiography and may determine the site of myocardial ischaemia when multiple obstructions are present.     

Delayed filling of the anterior interventricular artery. Apropos of 9 cases

Selective coronary angiography has shown that typical angina pectoris may occur in the absence of atheromatous coronary stenosis. Other causes of these attacks of pain have been found: coronary spasm, small vessel disease, abnormal dissociation of haemoglobin or metabolic disturbances of the myocardial cell. Of all the patients undergoing coronary angiography in 1984 at the Centre Cantini, 9 had no classical coronary lesions but delayed filling of the left anterior descending artery. This syndrome was described for the first time in 1972 by Tambe as the "slow flow velocity syndrome". The aim of this study was to analyse the clinical, ECG and haemodynamic profiles of those patients. Five of them also underwent stress Thallium myocardial scintigraphy. An ergometrine provocation test was performed afterwards under ECG control. Delayed filling was appreciated by comparison with the other vessels and also by measuring the filling time which was two or three times longer than in a control series of 9 patients with angina and normal coronary arteries. The difference was statistically significant. These findings were only observed in strictly normal coronary vessels; they were reproducible and unaffected by the administration of nitrate derivatives. In our series all 9 patients were men with an average age of 51.4 years. One patient was asymptomatic and had a history suggestive of myocardial infarction, and 4 others had typical angina of effort: all had abnormal exercise stress tests. The other 3 patients had spontaneous atypical chest pain, normal resting ECG and a negative exercise stress test (impossible in one case). The five stress Thallium scintigraphies showed myocardial perfusion defects.(ABSTRACT TRUNCATED AT 250 WORDS)     

Exercise echocardiography after stabilization of unstable angina: correlation with exercise thallium-201 single photon emission computed tomography.

The diagnostic usefulness of predischarge exercise echocardiography in 35 patients with unstable angina who responded to medical therapy was correlated with exercise thallium-201 single photon emission computed tomography (TI-SPECT) performed, on the average, three days after the exercise echocardiography. None of the patients had myocardial infarction prior to hospitalization or before TI-SPECT and none had left bundle-branch block on their rest electrocardiogram (ECG). Exercise echocardiography was positive in 21 patients and TI-SPECT in 24. The results of the two techniques were concordant in 28 of 35 patients (agreement = 80%, k = 0.57 +/- 0.14, p less than 0.001). Wall-by-wall comparison of the distribution of exercise-induced wall motion abnormalities with reversible thallium defects showed complete or partial correlation in all of 19 patients in whom both the tests were positive. A positive exercise ECG and positive exercise echocardiography identified 11 of 11 patients with angiographically verified significant coronary artery disease (CAD) and 11 of 12 patients (92%) with positive TI-SPECT. Thus, exercise echocardiography is a valuable addition to routine predischarge exercise test in the noninvasive diagnosis of myocardial ischemia and shows a good correlation with TI-SPECT in detecting and localizing ischemia in patients with unstable angina stabilized on medical therapy.     

Myocardial salvage following elective angioplasty for total coronary occlusion

A 65-year-old man with unstable angina had a critical left anterior descending coronary artery stenosis which progressed to total occlusion, without evidence of acute myocardial infarction. Thallium imaging revealed defects in the distribution of the left anterior descending coronary artery on exercise and redistribution, 4 h later. 99mTc radionuclide angiography showed a fall in left ventricular ejection fraction on exercise, and contrast cineangiography showed an extensive area of akinesia. Percutaneous transluminal coronary angioplasty was successful without any complications. Repeat radionuclide studies demonstrated improvement of both myocardial perfusion and function. Angiography at 1 year showed normal left ventricular contraction and no evidence of recurrent stenosis. The patient is free of angina, on no medication 2 years after angioplasty. This case illustrates the feasibility of myocardial salvage by elective coronary angioplasty in patients with unstable angina total coronary occlusion.     

Dipyridamole stress thallium perfusion scan for evaluating myocardial involvement in systemic sclerosis

To evaluate the usefulness of a dipyridamole stress thallium-201 (Tl-201) perfusion scan in detecting myocardial involvement in systemic sclerosis we performed Tl-201 scans, electrocardiograms (ECG), and echocardiograms (UCG) on 24 patients with systemic sclerosis (11 diffuse type, 13 limited type) sequentially selected randomly over an 8-month period, and compared the findings. Cardiac catheterization, coronary angiography (CAG), and right ventricular endomyocardial biopsy were performed as necessary. Of the 24 patients, Tl-201 scans revealed fixed defects (FDs; myocardial fibrosis) and/or reversible defects (RDs; myocardial ischemia) in nine patients, whereas ECG and UCG revealed defects in four and three patients, respectively. Biopsy specimens obtained from the three patients with FDs also showed both ECG and UCG abnormalities indicative of myocardial fibrosis despite their normal appearance with CAG. Autopsy findings on the heart of a patient who died of acute heart failure showed myocardial fibrosis predominantly in the left anteroposterior wall. This was consistent with the FDs area detected using the Tl-201 perfusion scan. In a patient with chronic heart failure, left ventriculography showed a decrease in the anterior wall motion of the left ventricle which coincided with the FDs area in the Tl-201 perfusion scan. In conclusion, dipyridamole stress Tl-201 scanning is useful for evaluating myocardial involvement in systemic sclerosis. Received: September 21, 2000 / Accepted: February 26, 2001