心肌缺血预适应对急性心肌梗死静脉溶栓冠脉再通的影响

目的探讨心肌缺血预适应对急性心肌梗死静脉溶栓治疗冠脉再通的影响。方法84例急性心肌梗死患者接受尿激酶静脉溶栓治疗,分梗死前有心绞痛组和梗死前无心绞痛组,依据临床间接血管再通标准观察两组再通情况,部分病例进行冠脉造影检查。结果两组再通率分别为74%和29.4%,差异有统计学意义(P<0.01)。结论心肌缺血预适应可提高急性心肌梗死静脉溶栓的冠脉再通。     

尿激酶溶栓联合介入术治疗急性脑梗死51例

目的评价急性脑梗死动脉内溶栓结合动脉溶栓后残余狭窄球囊扩张、支架置入术治疗的疗效。方法 51例急性脑梗死病人采取超选择接触性溶栓,尿激酶(UK)用微量泵以1×104U/min持续泵入,总量为60×104U～100×104U。在泵入尿激酶的过程中,通过导引导管造影,了解闭塞血管再通情况。结果颈动脉系统血管闭塞43例,椎-基底动脉系统闭塞2例。脑血管造影未发现明显的血管闭塞6例。颈内动脉闭塞再通率为63.64%;大脑中动脉闭塞再通率为63.63%;大脑中动脉分支闭塞再通率为55.56%;大脑前动脉闭塞(前交通动脉未开放)的1例再通;椎-基底动脉系统闭塞2例全部部分再通。动脉溶栓后颈内动脉残余明显狭窄3例行球囊扩张支架置入术。临床症状完全恢复正常或有明显好转的33例(64.71%)。结论动脉内接触性溶栓结合动脉溶栓后残余狭窄球囊扩张、支架置入术治疗急性脑梗死能明显提高治愈率,减少致残率,是安全、可靠、有效的治疗方法。     

冠脉内旋磨术在冠状动脉狭窄病变介入治疗中的应用--附9例报告

目的 通过应用冠脉内旋磨术（ROTABLA-TOR），球囊扩张术及支架置入术（STENTING）治疗冠状动脉狭窄病变，观察其对治疗冠脉血管狭窄的有效性及安全性。方法 对9例冠状动脉狭窄病变（经冠脉造影或血管内超声诊断）血管段先行冠状动脉旋磨术，然后以球囊扩张术，其中7例进行支架置入术，并对结果进行随访。结果 9例患手术全获成功，术中无出现不良反应或并发症。围手术期无并发症，术后随访6-18个月未出现心绞痛，心肌梗死及其他心脏病事件，结论 冠状动脉旋磨术与球囊扩张术及支架置入术是一种安全的和有效的治疗冠状动脉狭窄病变的方法之一。     

无先兆的再发性心肌缺血:组织型纤溶酶原激活剂静脉溶栓治疗成功后院内再缺血的危险因素分析

据报告急性心(肌)梗(塞)溶栓治疗后,其中18～32%的患者复发心肌缺血,指需紧急冠(状动)脉成形术或外科搭桥术,病变冠脉再堵塞或者发生心源性猝死。预测那类患者易发再缺血,有助于决定施行血管重建术与否。以往认为静脉注射链激酶后仍残留高度冠脉狭窄者易再次发作。但上述研究中患者例数较少,且对冠脉狭窄的程度及与梗塞区供血冠状动脉的形态学无详细评价,因而     

直接冠状动脉内支架植入术的可行性研究

目的 :评价直接冠状动脉 (冠脉 )内支架植入术的安全性和可行性。方法 :对 1999年 12月～ 2 0 0 0年 6月接受冠脉内支架植入术的 171例患者中 ,孤立性、狭窄程度≤ 90 %、参考直径≥ 2 .5mm、长度≤ 18mm ;无明显的钙化、扭曲和成角 ,非完全闭塞和分叉处病变者 5 6例行直接冠脉内支架植入术。观察住院期和术后 3个月随访期内不良心脏事件的发生率。结果 :5 6例的 6 0处病变成功 5 5处 (91.7% ) ;1处因支架未能通过狭窄处而改行球囊预扩张后的支架植入术 ,1处在支架植入后因远端血管发生撕裂而需再植入 1个支架 ,3例因支架植入后冠脉造影显示支架扩张不满意而再用高压球囊扩张。住院期和术后随访期内无心源性死亡、心肌梗死、急诊冠脉旁路术发生 ;9例行冠脉造影复查 ,其中 2例因显示再狭窄而行再次经皮腔内冠脉成形术治疗。与经球囊导管预扩张后行冠脉内支架植入术相比 ,直接冠脉内支架植入术费用降低 2 9% ,造影剂用量减少 2 7% ,手术操作和X线照射时间缩短 2 6 %和 2 5 %。结论 :直接冠脉内支架植入术在经选择的病变中安全可行 ,并可降低手术费用 ,减少X线照射。     

负荷超声心动图与负荷单光子发射计算机断层显像评价冠脉介入术后再狭窄（英文）

目的：探讨运用多巴酚丁胺负荷超声心动图（DSE）和硝酸甘油负荷单光子发射计算机断层灌注显像（SPECT）来评价经皮冠状动脉介入（PCI）术后再狭窄的价值。方法：39例PCI术后的患者,在冠状动脉造影前1周内接受DSE和SPECT检查,多巴酚丁胺剂量递增方案为5μg.kg-1.min-1,10μg.kg-1.min-1,20μg.kg-1.min-1,30μg.kg-1.min-1,40μg.kg-1.min-1五个级别,每级负荷维持3min。按照冠脉造影的结果确定DSE,SPECT的敏感性、特异性和准确度,分析比较DSE,SPECT和冠脉造影检查的结果。结果：与冠脉造影相比,SPECT、DSE检查评价PCI术后再狭窄的敏感性（83.3%比75.0%）,准确性（71.8%比87.2%）无显著差异P〉0.05,但与SPECT相比,DSE检查的特异性较高（66.7%比92.6%）,P〈0.05。结论：多巴酚丁胺负荷超声心动图评价经皮冠状动脉介入术后再狭窄准确,且特异性好于SPECT。     

经皮腔内冠状动脉成形术(附10例报告)

我院自1988.8～1992.11共完成经皮腔内冠状动脉成形术(PTCA)10例.患者均为冠心病,心肌梗塞后心绞痛8例,不稳定心绞痛2例.冠脉造影示2支血管病变4例,单支血管病变6例.10例PTCA中成功7例.共扩张8处狭窄,术后残余狭窄为0～20%.术后随访3个月～3年,其中冠脉造影随访1例,未见再狭窄.术后复查ECT,示心肌缺血明显改善.     

溶栓疗法中T波早期倒置的意义

观察接受溶栓治疗的急性心肌梗塞患者25例。根据溶栓开始后T波倒置时间≤4小时或＞4小时，将患者分为A、B两组。A组10例，B组15例。对比分析两组的临床判定溶栓后血管再通率，左室射血分数及冠脉造影TIMI分级情况。结果表明：A组再通率100％，B组20％（P＜0．001），左室射血分数A组明显高于B组，（55．6±10．8％VS47．6±12．0％P＜0．05），四周后做冠脉造影者14例，A组冠脉开通率明显高于B组（TIMI2—3级者4／5例VS3/9例）。早期T波倒置提示良好的再灌注，可能作为血管再通的又一项临床指标。     

经皮腔内冠状动脉介入术中肾上腺髓质素和内皮素水平变化与再狭窄的关系

目的 探讨冠心病患者行经皮腔内冠状动脉介入术（PCI）中冠脉循环中肾上腺髓质素（ADM）及内皮素（ET-1）浓度变化与术后再狭窄的关系。方法 70例冠心病患者分别于术前、冠脉造影后、球囊扩张（PTCA）后、术后10分钟采集冠状静脉窦血,采用放免法测定ADM、ET-1的浓度。患者于术后6个月或有心肌缺血复发证据时复查冠状动脉造影。结果 随访结果显示,再狭窄发生率为21．4％（15／70）,PCI术前及冠脉造影后冠脉循环中ADM、ET-1水平在有无再狭窄组间比较,无明显差异,球囊扩张后再狭窄组冠脉循环中ADM、ET-1含量明显高于无再狭窄组,术后10分钟ADM值在两组间比较,无明显差异,而ET-1在再狭窄组明显高于无再狭窄组。结论 球囊扩张后冠脉循环中ADM、ET-1水平与术后再狭窄关系密切,可作为预测PCI术后再狭窄的参考指标。     

经皮冠状动脉腔内成形术(PTCA)——139例分析及其并发症的预防和处理

139例PTCA,成功率为86.3%。未成功者19例中7例PTCA导管未能通过或达到狭窄区;6例因狭窄病变弥散伴钙化,扩张后压力阶差和狭窄减少不明显;6例为严重的急性血管闭塞,其中一例死亡。作者详细讨论了上述并发症的预防和处理,强调术前认真阅读冠脉造影电影片,分析病变性质是否适于扩张这是PTCA获得成功和预防并发症的关键。     

Prognostic value of 12-lead electrocardiogram during dobutamine stress echocardiography

The aim of this study was to assess the prognostic value of the 12-lead electrocardiogram (ECG) obtained during dobutamine stress echocardiography (DSE) in predicting subsequent cardiac events. We retrospectively analyzed 345 patients undergoing DSE in 1992-1994 and selected those patients with negative echo results for ischemia. Of the 200 patients with negative DSE results, a separate analysis of their ECG data was performed with results reported as either positive, negative, or nondiagnostic for ischemia. Follow-up was performed through a physician chart review and direct telephone contact. Event rates were determined for hard (myocardial infarction or cardiac death) and soft (hospitalization for angina and/or congestive heart failure, coronary angioplasty, or coronary artery bypass graft surgery) cardiac events occurring after the negative DSE for up to 6 years after the test. Death was also determined by referencing the patients' data with mortality data available on the Internet. There were 143 patients with ECG data reported as negative and 40 patients with ECG data reported as positive for ischemia. The hard and soft event rates were 1.5% and 9% per patient per year in the ECG negative group and 2% and 11% in the ECG positive group. There were no statistical differences in event rates between the two groups during the 5-year follow-up period. Our results suggest that the ECG result obtained during DSE does not confer any incremental prognostic value over the echo result.     

Myocardial ischemia due to coronary artery spasm during dobutamine stress echocardiography

Dobutamine stress echocardiography (DSE) is a useful and safe provocation test for myocardial ischemia. Until now, the test has been focused only on the organic lesion in the coronary artery, and positive DSE has indicated the presence of significant fixed coronary artery stenosis. The aim of the present study is to examine whether myocardial ischemia due to coronary spasm is induced by dobutamine. We performed DSE on 51 patients with coronary spastic angina but without significant fixed coronary artery stenosis. All patients had anginal attacks at rest with ST elevation on the electrocardiogram (variant angina). Coronary spasm was induced by intracoronary injection of acetylcholine, and no fixed coronary artery stenosis was documented on angiograms in all patients. DSE was performed with intravenous dobutamine infusion with an incremental doses of 5, 10, 20, 30, and 40 microg/kg/min every 5 minutes. Of the 51 patients, 7 patients showed asynergy with ST elevation. All 7 patients (13.7%) had chest pain during asynergy, and both chest pain and electrocardiographic changes were preceded by asynergy. These findings indicate that dobutamine can provoke coronary spasm in some patients with coronary spastic angina. When DSE is performed to evaluate coronary artery disease, not only fixed coronary stenosis, but also coronary spasm should be considered as a genesis of asynergy.     

Comparison of dobutamine stress echocardiography and exercise stress Thallium-201 SPECT for detection of myocardial ischemia after acute myocardial infarction treated with thrombolysis

In order to compare the ability of dobutamine stress echocardiography (DSE) and exercise Thallium-201 SPECT to detect myocardial ischemia in patients with myocardial infarction (Ml) treated with thrombolysis, 43 prospectively selected patients with Ml treated with thrombolysis underwent within 1 month from Ml DSE, stress-redistribution-reinjection Thallium-201 SPECT and coronary angiography. The echocardiographic and scintigraphic images were analyzed for the presence of myocardial ischemia using a 11-segment left ventricular model. DSE and exercise Thallium-201 SPECT detected myocardial ischemia in the infarct zone in 72 and 72 (31/43) of patients and ischemia at a distance in 12 (5/43) and 19 (8/43) of patients with a concordance of 67 and 88 , respectively. A significant agreement between DSE and exercise Thallium SPECT was found in the evaluation of the extent of both myocardial necrosis and stress-induced myocardial ischemia. DSE and exercise Thallium SPECT showed similar sensitivity (79 vs 76), specificity (60 vs 60) and accuracy (77 vs 74) for detection of a critical stenosis of the infarct-related artery; there was also no significant difference between the tests in sensitivity, specificity and accuracy for detection of the multivessel disease.In conclusion, initially after thrombolyzed MI, DSE and exercise Thallium-201 SPECT detect myocardial ischemia in the infarct zone in a high proportion of patients and show a similar accuracy for the diagnosis of a critical stenosis of the infarct-related coronary artery and of the multivessel disease.     

Coronary artery spasm during dobutamine stress echocardiography in a patient with angiographically normal coronary arteries.

Dobutamine stress echocardiography (DSE) has been extensively used for diagnostic and prognostic purposes in patients with suspected or known coronary artery disease. During DSE transitory alterations of myocardial wall mobility can occur in the absence of electrocardiographic alterations, or they can be associated with ST segment depression or even elevation on the electrocardiogram. ST segment elevation during DSE has been reported as an infrequent event, generally associated with previous myocardial infarction or coronary artery disease with critical lesions, since the positive inotropic and chronotropic effects of dobutamine produce an increase in myocardial oxygen demand, causing ischemia and segmental contractility abnormalities in patients with significant coronary stenosis. The present case relates to a patient referred for DSE after an ischemic treadmill exercise test. During DSE she presented ST segment elevation associated with chest pain. Subsequent coronary arteriography showed normal coronary arteries. We speculate that coronary spasm may have occurred in this patient, as a paradoxical response to the dobutamine-induced increase in coronary flow.     

Induced ischemia detected by dobutamine stress echocardiography in coronary heart disease patients after myocardial re-vascularization. Experience in a District General Hospital

Most episodes of myocardial ischemia in patients with known coronary artery disease (CHD) are asymptomatic. Silent myocardial ischemia (SMI) is an important predictor of adverse outcome in patients with proven coronary artery disease. beta-blockers are effective in suppressing ischemia, and improve clinical outcome in patients with coronary artery disease. At present, it is common practice to stop treatment with beta-blockers in clinically asymptomatic patients after coronary artery bypass graft (CABG) and/or myocardial re-vascularization (PTCA/Stent), although the possible presence of SMI/inducible ischemia after myocardial re-vascularization is not known. We examined 56 asymptomatic CHD patients after coronary artery bypass graft (n=36), percutaneous coronary angioplasty PTCA/stent (n=15), or both (n=5); therapy with beta-blockers was stopped in all of them after myocardial revascularization. All these patients underwent a dobutamine stress echocardiography test (DSE test). The DSE test was proposed to these asymptomatic CHD patients to investigate the possible presence of SMI/inducible ischemia after myocardial re-vascularization. All patients had history of myocardial infarction or evidence of mildly impaired left ventricular function at rest as assessed by cardiac catheterization. Abnormal DSE studies occurred in eight of the 56 patients (14%; 95% C.I.: 6-26%). Therapeutic approaches specifically targeted at reducing total ischaemic burden include pharmacologic therapy and myocardial revascularization. On the basis of these data, it can be concluded that asymptomatic CHD patients after myocardial re-vascularization must be re-evaluated to rule out SMI/inducible ischemia that can be treated (e.g. with beta-blockers) reducing cardiovascular morbidity and mortality.     

Accuracy of dobutamine stress echocardiography for the diagnosis of coronary artery stenosis in patients with myocardial infarction: the impact of extent and severity of left ventricular dysfunction.

OBJECTIVES: To assess the value of dobutamine stress echocardiography (DSE) in the prediction of the extent and location of coronary artery stenosis in symptomatic patients with old myocardial infarction and to study the impact of the severity of resting wall motion abnormalities (WMA) on the diagnostic accuracy of the test. PATIENTS: One hundred and thirty two symptomatic patients with old myocardial infarction. METHODS: DSE (up to 40 micrograms/kg/min, with atropine up to 1 mg) was performed in all patients. Ischaemia was defined as new or worsened WMA. For each coronary artery, regional wall motion in the corresponding territory was classified as normal, mildly, moderately, or severely impaired according to the wall motion score index. Significant coronary stenosis was defined as > or = 50% diameter stenosis. RESULTS: A positive DSE for ischaemia occurred in 87 of 111 patients with and three of 21 patients without coronary artery stenosis (sensitivity = 78%; CI 71 to 86, specificity = 86%; CI 79 to 92, accuracy = 80%; CI 73 to 87). The accuracy for the diagnosis of individual coronary stenosis was 69% in the presence of normal wall motion and 74%, 74%, and 61% respectively when there was mild, moderate, and severe WMA in the corresponding territories (P = NS). The sensitivity was higher in presence of mild or moderate WMA (73%) than with normal wall motion (53%) or severe WMA (56%, P < 0.05 in both). In territories subtended by a stenotic artery, the regional wall motion score index was not different with or without ischaemia. CONCLUSION: DSE had a good overall accuracy for the diagnosis of coronary artery stenosis in symptomatic patients with old myocardial infarction. The presence of resting WMA did not limit DSE as a method of eliciting myocardial ischaemia and diagnosing significant coronary artery stenosis in patients with old myocardial infarctions.     

Effect of serum uric acid on the positive predictive value of dobutamine stress echocardiography

There is controversial data regarding the relationship between uric acid (UA) and coronary artery disease and cardiovascular events. Despite the deleterious effects of hyperuricemia on endothelial function, the effect of UA on myocardial ischemia has not been previously studied. We aimed to investigate the relationship between UA and myocardial ischemia that was identified using dobutamine stress echocardiography (DSE). In this retrospective study, the laboratory and DSE reports of 548 patients were reviewed. The patients were divided into two groups based on the presence of ischemia and further subdivided into three groups according to the extent of ischemia (none, ischemia in 1–3 segments, ischemia in >3 segments). Serum UA levels were compared. Determinants of ischemia were assessed using a regression model. UA was increased in patients with ischemia and was correlated with the number of ischemic segments (p < 0.001). A cutoff value of UA > 5 mg/dl had 63.9 % sensitivity, 62.0 % specificity, 42.5 % positive predictive value (PPV), and 79.6 % negative predictive value for ischemia. When the positive DSE exams were further sorted according to the UA cutoff, the PPV of DSE increased from 80.2 to 94.0 %. Uric acid (odds ratio 1.51; 95 % CI 1.14–1.99), diabetes mellitus, HDL and glomerular filtration rate were found to be independent determinants of myocardial ischemia in DSE. Increased UA is associated with both the presence and extent of DSE-identified myocardial ischemia. A UA cutoff may be a good method to improve the PPV of DSE.     

Clinical relevance of chest pain during dobutamine stress echocardiography in women.

BACKGROUND: Dobutamine stress echocardiography (DSE) is commonly used for diagnosis and management of patients with known or suspected coronary artery disease. Chest pain occurring during DSE potentially provides additional diagnostic accuracy. Our experience suggests that chest pain occurs frequently in women undergoing DSE. HYPOTHESIS: It was the purpose of this study to determine the frequency with which chest pain occurs in women undergoing DSE and the relation to inducible ischemia or coronary artery stenosis. METHODS: To determine the prevalence and clinical significance or chest pain during DSE, we reviewed the records of 154 consecutive women undergoing DSE in our laboratory. Of these, 59 patients (37.5%) also underwent coronary angiography. The presence or absence of chest pain was correlated with ECG changes, left ventricular wall motion abnormalities during DSE, and coronary stenosis by angiography. RESULTS: Forty-one women (26%) developed chest pain during DSE. Patients experiencing chest pain were older (58.5 +/- 9.3 vs. 54.9 +/- 12.6; p = 0.05), and had lower resting heart rates (71 +/- 12.2 vs. 77.9 +/- 14.9; p = 0.008), but received similar maximum doses of dobutamine and reached comparable peak heart rates (131.1 +/- 17.4 vs. 133.5 +/- 21.7; p = NS). Patients with chest pain more commonly exhibited ST-segment depression > or = 1 mm during dobutamine infusion (13/41, 32%, vs. 17/113, 15%; p = 0.02), but chest pain showed no statistically significant correlation with abnormal DSE or with coronary stenosis. CONCLUSIONS: In women undergoing DSE, chest pain occurs in 26% and does not appear to be related to inducible myocardial ischemia. Electrocardiographic changes occur more frequently in patients who experience chest pain, but are also often unrelated to inducible myocardial ischemia.     

Acute myocardial infarction after a negative dobutamine stress echocardiogram.

Acute myocardial infarction is a rare complication of dobutamine stress echocardiography (DSE). We described angiographic findings of a patient who developed acute inferior ST segment elevation myocardial infarction 2h after a normal dobutamine stress echocardiogram. The patient failed thrombolysis and underwent coronary angiography, which showed 60% stenosis of proximal right coronary artery with a complex ulcerated lesion and intracoronary thrombus. These findings suggest that myocardial infarction following DSE does not necessarily occur in patients with severe obstructive coronary artery disease. High shear stress may result in destabilization of a complex plaque with subsequent thrombotic occlusion, despite the absence of a flow-limiting lesion at the time of DSE.     

Risk stratification after acute myocardial infarction: limitations of dobutamine stress echocardiography in females]

BACKGROUND: Dobutamine stress echocardiography (DSE) is an imaging test widely used for risk stratification of patients after acute myocardial infarction. METHODS: We evaluated the sensitivity of DSE with respect to the gender and the stenotic coronary artery in patients who survived a myocardial infarction and with angiographic evidence of single-vessel coronary artery disease. RESULTS: The sensitivity of DSE was generally low. In particular, it was significantly lower in the presence of stenosis of the left circumflex and right coronary arteries with respect to the left anterior descending coronary artery. In females it was lower, especially when the stenosis involved the right coronary and left circumflex arteries. CONCLUSIONS: Our data suggest that in female gender the use of other imaging tests and particularly of coronarography should be strongly recommended for risk stratification after acute myocardial infarction.