A clinical study of postinfarction angina (PIA): the significance of electrocardiographic ST segment changes during anginal attacks]

We studied the clinical significance of electrocardiographic ST segment changes during PIA attacks. Of 478 AMI patients admitted to the CCU of our hospital within 48 hours after onset, we evaluated 73 (15.3%) with PIA. According to electrocardiographic ST segment changes during PIA attacks, the patients were divided into three groups, namely ST elevation at the same infarction site (same site elevation group), ST depression at the same site (same site depression group), and ST depression at other sites (other site depression group), and their pathological condition was studied. There were 33 patients (45.2%) in the same site elevation group, 19 (26.0%) in the same site depression group, and 21 (28.8%) in the other site depression group. The predominant infarction areas were anteroseptal and inferior wall in the same site elevation group, NTMI in the same site depression group, and inferior wall in the other site depression group. PIA usually occurred within 4 days after the onset of infarction in the same site elevation group, and within 5-7 days in the other site depression group, but no uniform trend was observed in the same site depression group. With respect to the number of vessels showing disease, cases of single-vessel disease tended to predominate in the same site elevation group, while cases of three-vessel disease tended to predominate in the same site depression group and the other site depression group. Stenosis rates in the vessels responsible for infarction were high in the same site elevation group in the acute period. Prognoses were poorest in the same site depression group.(ABSTRACT TRUNCATED AT 250 WORDS)     

Recurrent ischemia after thrombolysis for acute myocardial infarction

BACKGROUND: Reliable predictors have yet to be found for recurrent ischemia after thrombolysis for acute myocardial infarction (AMI), nor do we know whether early angiography can herald recurrent ischemia. This study sought to investigate the relationship between recurrent ischemia and cardiac procedures after thrombolysis for AMI. METHODS: The Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries (GUSTO-I) trial prospectively studied recurrent ischemia, which was defined as the presence of angina and changes in hemodynamics or the electrocardiogram. Cox regression analysis was used to identify predictors of recurrent ischemia. Other variables examined included time to coronary angiography and revascularization. RESULTS: Of 21,772 US GUSTO-I patients, 6313 (29%) had recurrent ischemia before discharge. Women (hazard ratio [HR] 1.25, 95% confidence interval [CI] 1.17-1.33) and patients with hypercholesterolemia (HR 1.14, 95% CI 1.07-1.22) or prior angina (HR 1.40, 95% CI 1.32-1.49) had a higher likelihood of recurrent ischemia. Current smoking and hours to thrombolysis were inversely related to recurrent ischemia (HR 0.86, 95% CI 0.81-0.92, HR 0.97, 95% CI 0.95- 0.99, respectively). Patients who underwent angiography before recurrent ischemia had a marginally increased risk of ischemia within 12 hours after angiography (HR 1.2, 95% CI 1.1-1.4); ultimately, they had a considerably lower risk 1 week after angiography than did patients without angiography (HR 0.57, 95% CI 0.45-0.72). CONCLUSIONS: Female sex, hypercholesterolemia, prior angina, and nonsmoking status weakly predict recurrent ischemia. Early coronary angiography reduces recurrent ischemia, probably because high-risk patients are identified and revascularized.     

ST段抬高型急性心肌梗死溶栓后心电图改变的临床意义

目的通过分析急性心肌梗死抬高的ST段下降幅度,评价溶栓治疗过程中ST段改变对患者心功能的预测价值。方法96例ST段抬高型急性心肌梗死患者,入院后行溶栓治疗,并计算溶栓后2h内ST段抬高振幅总和(ΣSTE)的下降幅度。结果溶栓治疗2h后,ΣSTE较溶栓治疗前下降大于50%时,病人自觉胸痛症状消失,心功能得到较好保护。而ΣSTE较治疗前下降小于50%时,患者心功能不同程度受损。结论ST段抬高型急性心肌梗死的患者经早期溶栓治疗后,其抬高的ST段下降幅度可作为心肌血供能否恢复的间接预测指标,从而能较准确地反映心肌再灌注情况及预测心功能状态。     

ST段抬高型急性心肌梗死溶栓后心电图改变的临床意义

目的通过分析急性ST段抬高型心肌梗死（STEMI）患者治疗后抬高的ST段下降的幅度，评价溶栓治疗过程中ST段改变对STEMI患者心功能的预测价值。方法105例急性STEMI患者，入院后行溶栓治疗，并计算溶栓后2h内ST段抬高总和的下降幅度。结果溶栓治疗2h后，ST段抬高振幅总和较溶栓治疗前下降大于50％时，病人自觉胸痛症状消失，心功能得到较好的保护。而ST段抬高振幅总和较治疗前小于50％时，患者心功能不同程度受损。结论急性STEMI患者经早期溶栓治疗后，抬高的ST段下降幅度可作为心肌血供能否恢复的间接预测指标，从而能较准确地反映心肌再灌注情况及预测心功能状态。     

The clinical implications of electrocardiographic changes in first acute myocardial infarction

To assess the prognostic significance and the clinical implications of the electrocardiographic findings of the first acute myocardial infarction, the in-hospital mortality and complications and three-year follow-up of 180 patients were analyzed. The patients were divided according to the infarction type (transmural, non-transmural), the site, (anterior, inferior including posterior) and the absence or presence of ST depression in leads facing the site of infarction. The peak enzyme concentrations were significantly higher in those with transmural infarcts than in those with non-transmural infarcts, in anterior infarcts compared to inferior infarcts, and in those sites with ST depression than those without. The early complications of cardiogenic shock, congestive cardiac failure, and complete heart block were significantly higher in transmural infarcts compared to non-transmural, while late complications and mortality were the same in all groups and subgroups. This study demonstrated that ECG changes in the first acute myocardial infarction are of prognostic significance for the early clinical course, but cannot predict the late course or subsequent coronary events.     

Reciprocal electrocardiographic changes in acute myocardial infarction

If reciprocal electrocardiographic changes during acute myocardial infarction (AMI) are a result of ischemia of the wall opposite the AMI, a stress test is expected to induce similar changes in the corresponding electrocardiographic leads. Right atrial pacing was used as a myocardial stress method in 137 consecutive patients recovering from a transmural AMI, and the appearance of pacing-provoked ischemia before hospital discharge was correlated to the presence of absence of ST depression in the opposite wall during the initial 48 hours. Of the 137 patients, 83 (61%) had reciprocal changes; they were more common in inferior (87%) than in anterior (37%) AMI (p less than 0.01). Of 54 patients without reciprocal changes, only 5 (9%) had ST depression during predischarge pacing; however, of the 83 patients with reciprocal changes, 41 had pacing-induced ischemia (p less than 0.01) and 42 did not, indicating that in half of this group the reciprocal changes represent ischemia of the opposite wall. In the other half of the group, without ST depression during pacing, these changes may be a "mirror image" phenomenon. Follow-up showed that angina pectoris, positive treadmill test response 6 months later, or recurrent AMI all consequences of impaired myocardial blood supply, were significantly more frequent in patients with reciprocal changes. This group could be further separated according to the results of right atrial pacing, because angina pectoris or recurrent AMI were infrequent among those with reciprocal changes and negative pacing responses, but was frequent among those with reciprocal changes and positive pacing responses.(ABSTRACT TRUNCATED AT 250 WORDS)     

Hemodynamic profile of acute myocardial infarction as a function of electrocardiographic localization]

The haemodynamic profiles of 147 cases of myocardial infarction investigated within 30 hours of the clinical onset were studies in relation to the topography of the necrosis on the ECG: there were 36 inferior (I), 29 postero-inferior (PI), 22 antero-septal (AS), 38 antero-lateral (AL), 15 deep septal (DS), and 7 strictly posterior or lateral (PL). Simultaneous recordings of the diastolic pulmonary arterial pressures and the left ventricular diastolic pressures (pre-and post-a) have shown different degrees of correlation with the topographical site. The correlation found in AS, AL and I necrosis are clearer with respect to the pre-a. The PI necroses show no correlation. Graphs of left ventricular function as well as an analysis of the various other parameters show that the DS, the AL, and to a lesser extent the PI are associated with the grossest depression of left ventricular function. A study of the amplitude of the "a" wave also shows that the effect of infacts of the free wall of the left ventricule on the compliance is greater. A study of right ventricular function as well as the correlations between the pulmonary and right atrial pressures confirms the presence of right ventricular disfunction in DS and PI necroses. Impaired left ventricular function, impaired right ventricular function, and disorders of compliance seem to be the determining factors in changing the haemodynamics in the various ECG sites of infarction.     

急性心肌梗死再灌注后心电图ST段抬高的意义

目的：探讨急性心肌梗死（AMI）患者接受经皮冠状动脉腔内成形术（PTCA）治疗心电图ST段持续高与临床预后的关系。方法：AMI患者共30例,比较PTCA前及术后1h12导联心电图抬高ST的总和,按ST段下降幅度分为两组,A组：AT段下降≥50％,B组：ST段下降＜50％。行小剂量多巴酚丁胺负荷超声心动图检查并随访复查超声心动图。结果：AMI发病早期基础状态和负荷状态及发病后第1、2、3个月左室射血分数（LVEF）A组均明显大于B组。多巴酚丁胺负荷状态下主动脉峰值血流加速度、每搏输出量及每搏指数A组明显大于B组。基于状态和负荷状态下总室壁运动积分指数（GWMSI）和梗死区室壁运动积分指数（IWMSI）A组均明显小于B组,AMI发病后1、2、3个月GWMSI A组均明显小于B组。发病第1、2个月IWMSI两组间差异无统计学意义。发病第3个月IWMSI A组明显小于B组。AMI直接PTCA后心电图ST段持续抬高的患者左室收缩功能及收缩储备功能以及梗死区室壁运动的恢复明显低于ST段迅速下降者。     

Shock after acute myocardial infarction A clinical and hemodynamic profile

Clinical features, predisposing factors, precipitating events, laboratory and hemodynamic observations, pathologic findings, prognostic indicators and the results of therapy are surveyed for 73 patients in whom shock developed after acute myocardial infarction. The incidence of shock was 15 percent, and the mortality 86 percent. It was not possible to differentiate patients with shock from those with acute infarction alone on the basis of age, anamnestic data, delay before hospitalization or anatomic location of infarction. No precipitating cause for shock other than acute infarction itself was consistently present. Hypovolemia, anemia, arrhythmia and drugs could not be incriminated as important factors in the genesis of shock. Extensive myocardial damage, coronary atherosclerosis and left ventricular hypertrophy were found at postmortem examination in most patients who died, but similar findings were noted in a group of patients in the coronary care unit who died without evidence of shock during the period of the study. Delay in onset of shock in many cases suggested progression of cardiac damage after the initial clinical event. Hemodynamic studies in 19 patients showed that cardiac index was less than half of the normal index, stroke volume index about a third of normal, and peripheral resistance generally increased. We conclude that patients who have the highest risk can be identified from various clinical and hemodynamic observations. It is appropriate to consider such patients for unconventional therapy.     

急性前壁心肌梗死合并下壁导联ST段下移的临床意义

48例首次急性前壁心肌梗死患者中伴下壁导联ST段平均下移>1mm、持续时间>48h者,CK和CK-MB的平均峰值更高,核素检查左室射血分数<40％,左室下壁运动障碍、出现放射性稀疏或缺损区的发生率也更高(P<0.05或<0.01)。说明这类病人有下壁心肌缺血,且可能心肌坏死面积更广。     

急性前壁心肌梗塞时下壁导联心电图ST段变化的意义

探讨ＥＣＧ胸前导联ＳＴ段抬高伴下壁Ⅱ，Ⅲ，ａＶＦ导联ＳＴ段压低与冠状动脉病变的关系。对６０例急性前壁心肌梗塞病例进行回顾分析，所有病人于发病后４周左右行冠状动脉造影检查。结果（１）３３例前降支单支血管病狭窄达９０％－１００％组，７７．８％出现Ⅱ，Ⅲ，ａＶＦ导联ＳＴ段压低０．１≥ｍＶ，狭窄７０％８９％组仅２３．１％出现Ⅱ，Ⅲ，ａＶＦ导联ＳＴ段压低≥０．１ｍＶ，两组间在统计学差异有极显著性。（２）６０     

Clinical significance of inferior ST elevation during acute anterior myocardial infarction.

OBJECTIVES--To clarify the genesis and clinical significance of inferior ST elevation during acute anterior myocardial infarction. PATIENTS AND DESIGN--A total of 106 patients with first acute anterior myocardial infarction (< or = 6 h) were divided into two groups according to the presence (group A, n = 12) or absence (group B, n = 94) of ST elevation of > or = 1 mm in at least two of the inferior leads on the admission electrocardiogram. RESULTS--On admission electrocardiograms, group A had a smaller summed ST deviation in the lateral limb leads than group B. On emergency coronary arteriograms, the incidence of a wrapped left anterior descending artery was higher in group A than in group B (100% v 27%, P < 0.01). The incidence of occlusion of a left anterior descending artery distal to its first diagonal branch was higher in group A than in group B (100% v 46%, P < 0.01). Peak serum creatine kinase activity and in-hospital mortality tended to be lower in group A than in group B. Group A had better left ventricular ejection fraction and regional wall motion in the anterobasal and anterolateral regions in the chronic phase than group B. In contrast, regional wall motion in the diaphragmatic region was reduced to a greater extent in group A than in group B. CONCLUSIONS--Inferior ST elevation during acute anterior myocardial infarction appears only in the presence of a combination of a lesser degree of transmural ischaemic myocardium in the anterobasal and anterolateral wall together with transmural ischaemic myocardium in the inferior wall; in all cases there was occlusion of a wrapped left anterior descending artery distal to its first diagonal branch. Patients with such an ST elevation appear to have a better in-hospital prognosis than those without it.     

Clinical significance of precordial ST segment depression during acute inferior myocardial infarction

To investigate the mechanisms and clinical significance of precordial (V1-V4) ST segment depression during acute inferior myocardial infarction, stress thallium-201 scintigrams and coronary angiograms were obtained within four to eight weeks after the onset of myocardial infarction in 37 patients experiencing their first acute inferior myocardial infarction. Among 18 patients with precordial ST depression (group 1), 11 with concomitant disease of the left anterior descending artery (LAD) had positive results on exercise test, whereas in seven patients without LAD lesion, only two had positive exercise test (p less than 0.01). In 19 patients without precordial ST depression (group 2), 11 had severe stenosis in the LAD. However, among these 11 patients, only two had positive exercise tests. Patients with precordial ST depression demonstrated a higher frequency of positive exercise tests than those without it (p less than 0.01). On stress thallium-201 scintigraphy, a perfusion defect involving the inferior wall was present in all patients, but additional anterior wall ischemia was present in only five of the 18 patients in group 1. These five patients had chest pain on exercise tests and a severe stenosis greater than 90% in the LAD. There was no significant difference in the frequency of additional posterolateral wall infarction between groups 1 and 2. In 18 patients in group 1, sigma ST (total degrees of ST segment depression in leads V1, V2, V3, and V4 in the acute stage) was significantly greater in 11 patients with LAD lesion than in seven without (p less than 0.05), and sigma ST greater than five mm was observed in 12 of 13 patients who had additional anterior wall ischemia and posterolateral wall infarction on stress thallium-201 scintigraphy (p less than 0.05). Myocardial revascularization, such as aortocoronary bypass surgery or percutaneous transluminal coronary angioplasty (PTCA), was performed in six of the 18 patients in group 1 in the chronic stage, but in only one of the 19 patients in group 2. Thus, in patients with initial acute inferior myocardial infarction, those with precordial ST depression seemed to be a high-risk group. It was suggested that, during the early stage of myocardial infarction, this abnormality on electrocardiograms is related to the summation of effects of anterior wall ischemia and posterolateral wall infarction. Furthermore, the sigma ST evaluation is useful in differentiating a mirror image of inferior wall infarction from anterior wall ischemia and posterolateral wall infarction as the mechanism of precordial ST depression.     

Pericardial effusion in acute myocardial infarction: clinical feature and significance]

To determine the incidence and clinical significance of pericardial effusion after acute myocardial infarction, two-dimensional echocardiography was serially performed in 137 consecutive patients. Pericardial effusion was observed in 45 patients (33%), of whom 22 were followed until they recovered and were discharged. Pericardial effusion was more frequent in patients with anterior acute infarction than those with inferior acute infarction, and so it was in non-recanalized patients than in recanalized ones. Patients with pericardial effusion had higher peak levels of creatine kinase, higher wall motion score indices, and higher defect scores of thallium imagings. The improvement of regional wall motion at an infarct zone in patients with pericardial effusion was less regardless of the successful early recanalization. These results show that pericardial effusion is a common event in patients with acute myocardial infarction and observation of transition of pericardial effusion is important for predicting prognosis.     

Clinical significance of transmural versus nontransmural electrocardiographic changes in patients with acute myocardial infarction

Two hundred thirty patients with probable or definite acute myocardial infarction were observed in a coronary care unit. The electrocardiogram showed changes in the S-T segment and T wave associated with a definitely abnormal enzyme curve in 45 patients (group I), with minimal enzyme rises in 33 patients (group II) and with development of Q waves and evolutionary changes in the S-T segment and T wave in 152 patients (group III). The incidence of supraventricular arrhythmias, ventricular premature beats and primary ventricular tachycardia was similar in all groups. The incidence of shock and mortality rates was similar in groups I (22 and 37 per cent, respectively) and III (18 and 19 per cent, respectively) and significantly greater when compared with group II (3 and 3 per cent, respectively) (p <0.05). There was a significant increase (p <0.05) in maximal serum lactic dehydrogenase (LDH) and serum glutamic oxaloacetic transaminase (SGOT) in patients with severe pump failure when compared to those in patients who had no or mild congestive heart failure. The incidence of severe pump failure and mortality is closely reflected in the magnitude of the enzyme rise but not in the electrocardiographic changes. Although a subset of patients with acute myocardial infarction in whom the prognosis was excellent (group II) was identified, the hazard of arrhythmic deaths (judged by the incidence of premature ventricular contractions and ventricular tachycardia) was similar in all groups.     

急性心肌梗塞患者平板运动试验中QT离散度的变化及意义

目的 探讨急性心肌梗塞（ＡＭＩ）患者平板运动试验（ＴＥＴ）时ＱＴ间期离散度（ＱＴｄ）的变化,观察其与预后的关系。方法 ３８例ＭＡＩ３周以上患者,男性２２例,女性１６例,采用ＴＥＴ同步记录１２导联心电图,计算ＱＴｄ,观察运动和随访中严重室性心律失常的发生情况,回顾性分析其运动前后ＱＴｄ的变化,并与冠状动脉造影（ＣＡＧ）结果加以对比。结果 严重室性心律失常组（Ａ组）１５例：ＴＥＴ时出现室早〉６次／分者     

Clinical and prognostic significance of silent myocardial ischemia in survivors after acute myocardial infarction

To clarify the clinical and prognostic significance of silent myocardial ischemia (SMI) after acute myocardial infarction (MI), the clinical characteristics and long-term prognosis after discharge in 525 medically treated survivors after acute MI were investigated. According to the presence of post-infarction angina and results of all exercise tests during hospitalization, 309 patients without ischemic episodes were classified into control group, 59 patients with SMI into SMI group and 157 patients with post-infarction angina into AP group. Previous MI (29%, 24%, 11%, respectively), non-Q wave MI (34%, 34%, 15%) and multivessel disease (69%, 61%, 33%) were more frequent in the SMI and AP groups than in the control group. These indicated clinical characteristics in patients with SMI were similar to those in patients with angina pectoris. The incidence of angina prior to MI onset in patients with SMI was lower than in patients with post-infarction angina. This may suggest that there is some common mechanism keeping them silent in the pre- and post-MI period. During the mean follow-up period of 5.5 years, 93 patients died and 78 had a recurrent MI. Cumulative total and cardiac mortality, and incidence of recurrent MI by actuarial method were higher in the SMI as well as AP group than in the control group. There was no statistically significant difference in prognosis between SMI and AP group. We conclude total ischemic burden, not only symptomatic but SMI, should be treated using currently available therapeutic modalities for further improvement of long-term prognosis in survivors after acute MI.