The Initial Electrocardiographic Pattern in Acute Myocardial Infarction

Background: The ECG is the most widely used accessory for early diagnosis and risk stratification of patients with acute myocardial infarction (AMI). Previous studies have concentrated on the association between either the number of leads with ST segment deviation (elevation and depression) or the total amount of ST segment elevation and/or depression and prognosis. However, the results are conflicting. Methods: A different method is to use the grades of ischemia as an estimate of infarct or size and prognosis. Grade I ischemia is defined as tall peak T waves with < 0.1 mV ST segment elevation; grade II as ST segment elevation with positive T waves, without distortion of the terminal portion of the QRS; and grade III as ST segment elevation, positive T waves, and distortion of the terminal portion of the QRS. Grade III ischemia on the admission ECG is associated with larger final infarct size and increased mortality. Results: In patients with inferior wall AMI, especially those with prior infarction, the pattern of precordial ST segment depression is even more important and maximal ST depression in V4-V6 is associated with high mortality. Moreover, meticulous interpretation of the initial ECG pattern provides information about the probable site of the culprit obstructive coronary lesion. Conclusion: Thus, the admission ECG of AMI can assist not only in diagnosis, but also in estimation of infarct size, correlation with the underlying coronary anatomy and risk stratification.     

急性心肌梗死后应激性高血糖与心室重构以及预后的关系

目的:探讨急性心肌梗死(AMI)急性期的空腹血糖水平与心室重构之间的相关性以及与1个月、1年死亡率的关系。方法:连续248例非糖尿病AMI患者,排除了其他引起慢性应激的因素,测定患者次日晨起空腹血糖(FG)。AMI后第2周进行超声心动图检查,随访患者1个月和1年的存活情况。进行FG和超声心动图各参数间的相关分析。比较不同血糖水平下的1个月和1年死亡率。结果:①FG与左室射血分数(r=-0.287,P<0.01),左室后壁厚度(r=-0.205,P<0.01)均呈轻度负相关,与左室舒张末径(r=0.166,P<0.05),左室收缩末径(r=0.312,P<0.01)均呈轻度正相关。②合并应激性高血糖者预后较无应激性高血糖者差(1个月死亡率:19.8%vs.7.5%,P<0.01;1年死亡率26.7%vs.12.2%,P<0.01)。血糖重度升高者预后较轻度升高者差(1个月死亡率:33.3%vs.13.2%,P<0.05;1年死亡率42.4%vs.19.1%,P<0.05)。结论:AMI急性期的FG水平作为机体应激程度的标志与左心室重构相关,FG高者,1个月和1年预后均较差。     

心肌缺血预适应对初发急性心肌梗死病人临床及预后的影响

目的探讨心肌缺血预适应对初发急性心肌梗死（AMI）病人梗死范围及近期预后的影响。方法对116例初发AMI骗人．按梗死前48h有无心绞痛分为缺血预适应组（IPC，64例）、无缺血预适应组（NIPC，52例），对比分析两组病人的临床资料。结果IPC组比NIPC组的心肌梗死范围小（P〈0．05），血清心肌酶学峰值低（P〈0．05），恶性心律失常、心力衰竭、心源性休克、室壁瘤发生率及病死率均明显降低（P〈0．05）。结论心肌缺血预适应具有保护心肌、缩小梗死范围。改善近期预后的作用。     

The Prognosis for Patients Referred with Suspected Acute Myocardial Infarction

ABSTRACT. Engby B, Strunge P, Olsen J. (Department of Internal Medicine, Horsens Hospital, Horsens, Denmark.) The prognosis for patients referred with suspected acute myocardial infarction. A follow-up investigation of the prognosis of 381 patients admitted with suspected acute myocardial infarction (AMI) has been carried out in respect of later AMI or death. During hospitalization the patients were divided into groups with particular attention to patients with no demonstrable myocardial infarction but with ischaemic heart disease (non-AMI) and patients with confirmed AMI. All patients were subjected to follow-up for 43 months (range 37–54). The mortality from cardiovascular causes after four years was 26.2% of 130 non-AMI patients and 25.8% of AMI patients. The majority of new infarctions were found in the AMI patients, but with even increase in both groups, 50% occurring within the first 12 months. The groups were studied with regard to earlier manifestations of ischaemic heart disease and heart failure during hospitalization, without any difference being observed. Due to the poor prognosis the question is raised whether non-AMI patients as a group should be offered prophylactic therapy.     

High Human Antimicrobial Peptide LL-37 Level Predicts Lower Major Adverse Cardiovascular Events after an Acute ST-Segment Elevation Myocardial Infarction

Aims: We previously associated acute ST-elevation myocardial infarction (STEMI) with decreased plasma LL-37 levels. Therefore, this study investigated whether plasma LL-37 levels could predict ischemic cardiovascular events in patients after STEMI. Methods: We prospectively collected peripheral plasma samples and clinical and laboratory data from consecutive patients who presented with STEMI and underwent primary percutaneous coronary intervention at Fuwai Hospital between April and November 2017. Enzyme-linked immunosorbent assay measured plasma LL-37 levels, and we followed the patients for 3 years. Major adverse cardiovascular events (MACEs) were a composite of all-cause mortality, reinfarction, unscheduled revascularization, or ischemic stroke. Results: The study included 302 patients divided into high (≥ median) and low LL-37 level (＜median) groups. The cumulative incidence of MACE (29.1% vs. 12.6%, p=0.0003), all-cause death (12.6% vs. 3.3%, p=0.003), reinfarction (7.1% vs. 2.0%, p=0.04), and unscheduled revascularization (13.0% vs. 5.4%, p=0.04) were higher in the low than those in the high LL-37 level group. Multivariable Cox regression analysis showed that higher LL-37 level independently predicted lower risks of MACE (hazard ratio [HR] 0.390; 95% confidence interval [CI] 0.227–0.669; p＜0.001), all-cause death (HR 0.324; 95%CI 0.119–0.879; p=0.027), and unscheduled revascularization (HR 0.391; 95%CI 0.171–0.907; p=0.027). Conclusions: High basal plasma level of human LL-37 may predict lower 3-year risks of ischemic cardiovascular events in patients after STEMI.     

Myocardial Viability Detected by Myocardial Contrast Echocardiography—Prognostic Value in Patients after Myocardial Infarction

Objective: This study aimed to assess the role of myocardial contrast echocardiography (MCE) as a predictor of cardiac events and death in patients with acute myocardial infarction (AMI). Methods: Eighty‐six patients underwent primary percutaneous coronary angioplasty for AMI. Segmental perfusion was estimated by MCE in real time at mean 5 days after PCI using low MI (0.3) after 0.3–0.5 ml bolus injection of intravenous Optison. MCE was scored semiquantitatively as: (1) normal perfusion (homogenous contrast effect), (2) partial perfusion (patchy myocardial contrast enhancement), (3) lack of perfusion (no visible contrast effect). A contrast score index (CSI) was calculated as the sum of MCE scores in each segment divided by the total number of segments. The patients were followed up for cardiac events and death. Results: A CSI of >1.68 was taken to be a predictor of cardiac events and death. Death occurred only in patients with CSI >1.68. Patients with CSI >1.68 had a significantly (P = 0.03) higher incidence of cardiac death or cardiac events (75%) compared to those with CSI <1.68 (27%). The absence of residual perfusion within the infarct zone was an independent predictor of death and cardiac events (P = 0.02). Conclusions: The absence of residual myocardial viability in the infarct zone supplied by an infarct‐related artery is a powerful predictor of cardiac events in patients after AMI. (Echocardiography 2010;27:430‐434)     

The Diagnostic Value of 12‐Lead Electrocardiogram in Predicting Infarct‐Related Artery and Right Ventricular Involvement in Acute Inferior Myocardial Infarction

Background: The aim of the present study was to investigate the predictive value of presentation and 24‐hour electrocardiograms in defining the infarct‐related artery (IRA), its lesion segment, and the right ventricular involvement in acute inferior myocardial infarction (Ml). Methods: One hundred forty‐nine patients with acute inferior MI were included. Infarct‐related artery, its lesion segment, and the validity of new ECG criteria for the diagnosis of right ventricular Ml (RVMI) were investigated by means of criteria obtained from admission and 24‐hour ECGs. Results: The presence of ST‐segment elevation in lead III > lead II criterion (Criterion 1) and ST‐segment depression in lead I > lead aVL criterion (Criterion 2) from admission ECG defined the right coronary artery (RCA) as IRA with a sensitivity of 64% and a specificity of 100%. These two criteria also defined the proximal or mid lesions in RCA as culprit lesions (sensitivity of 99%, specificity of 96%). Absence of these two criteria indicated Cx as IRA with a sensitivity of 50% and a specificity of 97%. The depth of Q wave in lead III > lead II criterion (Criterion 3) had no value for discrimination of IRA, but the width of Q wave in lead III > lead II criterion (Criterion 4) supported the RCA to be IRA with a sensitivity of 60% and a specificity of 61% (Criteria 3 and 4 were obtained from 24‐hour ECGs). The finding of Criterion 1 plus Criterion 5 (ST elevation in V₁ but no ST elevation in V2) on admission ECG had a sensitivity of 63% and a specificity of 99% in the diagnosis of RVMI. Conclusion: We concluded that 12‐lead ECG is a cheap, easy, and readily obtainable diagnostic approach in discrimination of IRA and its culprit lesion segment. However, despite high specificity, due to moderate degree sensitivity, its value for the diagnosis of RVMI is questionable. A.N.E. 2001; 6(3):229–235     

Atrial Fibrillation in Acute St-Elevation Myocardial Infarction: Clinical and Prognostic Features

Atrial fibrillation (AF) is a common arrhythmia in the setting of acute coronary syndrome and acute ST-elevation myocardial infarction (STEMI). This review summarizes recent evidence on the clinical and prognostic significance of pre-existent and new-onset AF in acute STEMI patients and highlights new emerging predictors of AF development in the era of contemporary treatment.     

Prognostic Value of Megatroponinemia After Myocardial Infarction

Purpose

The purpose of this study is to investigate the prognostic value of megatroponinemia (troponins >100 ng/mL), as a predictor of major adverse cardiac events such as recurrent angina, myocardial infarction, and death in patients presenting with acute myocardial infarction.

Methods

Over a period of 2 years, we identified 27 patients admitted with acute myocardial infarction and troponin I values >100 ng/mL. These patients were followed-up for the short term during their hospitalization as well as for an intermediate term of 18 ± 14 months after their initial presentation with acute myocardial infarction for major adverse cardiac events including recurrent angina, myocardial infarction, and death.

Results

Of the 27 patients, one died 5 days after myocardial infarction and 26 were discharged home in stable condition, with few requiring timely intervention. Six patients were lost to follow-up. Five patients died during follow-up, 4 from recurrent myocardial infarction and 1 died from metastatic renal cell carcinoma. Twelve patients had non-fatal myocardial infarction, with 10 being acute ST elevation; 3 patients had recurrent angina.

Conclusion

Patients presenting with an acute myocardial infarction and troponins >100 ng/mL have continued incremental risk of excessive major adverse cardiac events during short and intermediate follow-up period.     

ST段抬高急性心肌梗死的梗死相关动脉临床心电图诊断

急性心肌梗死是指因持续而严重的心肌缺血所致的部分心肌急性坏死.了解梗死相关动脉对急性心肌梗死的诊断起了决定性的作用.临床诊断冠脉病变常运用冠脉造影的方法,需要昂贵的设备和有一定条件的医院才能够做到.而使用心电图诊断ST段抬高急性心肌梗死的梗死相关动脉临床简单、易行.最近有不少研究都证明了该方法是可行的,现就此作一综述.     

急性心肌梗死心脏破裂机制的研究进展

心脏破裂是急性心肌梗死(AMI)最严重的并发症之一,占AMI院内死因的20%～31%。现就目前AMI心脏破裂机制的研究现状和进展作一综述。新的观点认为,心肌重构缺陷可能会倾向于发生心脏破裂。基质金属蛋白酶系统在细胞外基质重构和心脏破裂中具有重要作用。肾素-血管紧张素系统及神经激素系统的激活、心肌细胞凋亡、基因易感性也可能参与了心脏破裂的发生。     

判断急性下壁心肌梗死罪犯血管的心电学新标准

为验证心电图aVL导联QRS波群变化能否作为下壁急性心肌梗死 (AMI)罪犯血管的判定标准 ,比较 6 0例下壁AMI患者aVL导联QRS波群变化与冠状动脉造影结果的相关性 ,分析aVL导联QRS波群两种模式 (Ⅰ型 :S/R≤1/ 3,ST段抬高≤ 1mm ;Ⅱ型 :S/R >1/ 3,ST段抬高 >1mm)对判断下壁AMI罪犯血管的临床价值。结果 :aVL导联的Ⅰ型QRS波群改变在左冠状动脉回旋支闭塞 (LCX)组出现率为 89% ,右冠状动脉闭塞组为 2 4% (P <0 .0 0 1)。Ⅱ型改变在LCX组出现率为 11%、RCA组为 76 % (P <0 .0 0 1)。Ⅰ型心电图变化预测LCX闭塞的敏感度为 89%、特异性为 76 %。Ⅱ型心电图改变预测RCA闭塞的敏感度为 76 %、特异性为 89%。结论 :aVL导联的Ⅰ型QRS波群变化是判断LCX型AMI敏感、特异的预测指标 ,而Ⅱ型QRS波群变化是RCA型AMI有效的预测指标     

Relationship between Enzymatically Estimated Infarct Size and Short- and Long-term Survival after Acute Myocardial Infarction

Abstract In 585 patients with acute myocardial infarction (AMI) and no previous MI the maximal activity of serum heat-stable lactate dehydrogenase (LD) (EC 1.1.1.27) activity was related to 1-year and 2-year mortality rates. All patients participated in a double-blind trial with metoprolol during the first three months after an AMI. Thereafter both groups were treated in a similar way. A strong relationship was found between LD maximum activity and the in-hospital prognosis (p<0.001), the 1-year survival rate (p<0.001) and the 2-year survival rate (p<0.001). When the patients who were alive after primary hospitalization were analyzed as a separate group, the relationship between LD maximum activity and 1-year and 2-year survival rates remained (p<0.001). In a subsample of 171 patients the maximal activity of creatine kinase (CK) (EC 2.7.3.2) and CK subunit B did not correlate either with in-hospital, 1-year or 2-year survival rates. We conclude that, when a sufficiently large number of patients are investigated, there is a strong relationship between serum enzyme maximum activity and short- and long-term survival.     

延迟PCI对急性心肌梗死患者左心室重构及心脏事件的影响

目的观察延迟经皮冠状动脉支架植入术（PCI）对急性心肌梗死患者左心室重构及心脏事件的影响。方法将经药物治疗后病情稳定的急性心肌梗死患者分成延迟PCI治疗＋药物治疗组（A组）和单纯药物治疗组（B组）。在入院即刻、7d和180d采用超声心动描记术评价左心室整体功能,并进行比较。结果A组患者行PCI术后180d左心室射血分数（LVEF）及左心室舒张末期内径（LVESd）、左心室收缩末期内径（LVESd）等指标（58．49±6．65、45．20±5．15、32．04±8．55）与术后7d（51．69±5．00、47．77±3．10、37．57±5．92）相比,差异有统计学意义（P〈O．05）,与B组术后180d（53．16±5．92、46．20±4．60、35．40±7．40）比较,差异均有统计学意义（均P〈0．05）;PCI术后7d两组上述指标比较,差异无统计学意义（均P〉0.05）。讨论延迟PCI有助于防止左心室重构．改善心功能,使心脏不良事件明显下降。     

急性心肌梗塞心室晚电位影响因素的研究

研究281例未经溶栓及其它早期介入性治疗干预的急性心肌梗塞连续病例各种临床变量与心室晚电位的关系。单因素及逐步多元 Logistic 回归分析结果表明,肌酸磷酸激酶峰值和冠状动脉病变数目是影响晚电位检出率的最重要变量。换言之,急性心肌梗塞中影响晚电位存在的最重要因素是梗塞和缺血区域的大小。     

缺血性J波预测急性心肌梗死后恶性室性心律失常的临床价值

目的:分析急性心肌梗死J波与恶性心律失常的关系,探讨J波预测急性心肌梗死后恶性室性心律失常的临床价值。方法:将126例急性心肌梗死患者根据心电图是否存在J波分为观察组和对照组。结果:两组患者心律失常情况差异总体无显著性(P0.05),但是个别指标有显著性差异(P0.05)。J波呈顿挫型、振幅高、持续时间长者提示发生心脏事件危险性增加。结论:心电图中对J波综合征的诊断可以早期发现高危人群,提高对心源性猝死的防范,临床预测价值大。     

Effects on Mortality during Five Years after Early Intervention with Metoprolol in Suspected Acute Myocardial Infarction

ABSTRACT This study reports the mortality over a 5-year-period determined a double-blind trial, which evaluated the effect of early intervention with metoprolol in suspected acute myocardial infarction. In all, there were 1 395 randomized patients, 698 and 697 of whom were allocated to metoprolol 200 mg daily and placebo treatments, respectively, for the first 3 months. Thereafter, the two groups were treated in a similar fashion implying β-blockade to a majority. Within the first 3 months, mortality in the metoprolol group was 5.7% versus 8.9% of the placebo group (p = 0.02). This difference persisted after 2 years (metoprolol 13.2%; placebo 17.2%; p = 0.04). Over a 5-year-period, 24.2% of the patients who originally were allocated to metoprolol had died as compared to 25.7% of those originally allocated to placebo (p > 0.2). Among patients in whom treatment started early (≤ 8 hours after onset of pain = the median delay time), enzyme activities in the metoprolol group was lower (p = 0.03) than in the placebo group. Mortality during the first 2 years among these patients treated early was lower in the metoprolol (11.8%) than in the placebo group (17.3%; p = 0.04). Corresponding figures after 5 years were 22.0% and 25.3%, respectively (p > 0.2). Among patients in whom treatment started later than 8 hours onset of pain, there was neither any difference in enzyme activity nor in mortality after 2 and 5 years. It can be concluded that early treatment with metoprolol in suspected acute myocardial infarction reduced mortality during the first 3 months compared with placebo. The difference persisted after 2 years. However, 5 years after randomization, no significant difference in mortality was observed between the two treatment groups.