Prognosis during one year for patients with myocardial infarction in relation to the development of Q waves: experiences from the Miami trial

From a randomized multicenter trial with metoprolol in suspected acute myocardial infarction (n = 5778) we report on the outcome during a one-year follow-up in patients with confirmed infarction (n = 4106) in relation to whether or not they developed Q waves. Patients with Q waves had another pattern of risk factors, including lower age and a lower occurrence of previous infarction, angina pectoris, and congestive heart failure. After one year follow-up, 14.3% of the patients with Q waves had died versus 9.0% of those without Q waves (p less than 0.001). Reinfarction during the first year occurred in 8.2% of patients with Q waves and 12.5% of patients without Q waves (p less than 0.001). After one year, other morbidity aspects appeared relatively independent of the original presence of Q waves. In conclusion, during the first year after development of acute myocardial infarction the appearance of Q waves during the first three days is associated with a higher mortality and a lower reinfarction rate, whereas other morbidity aspects appear to be relatively independent of its presence.     

Abnormal Q waves on the admission electrocardiogram of patients with first acute myocardial infarction: Prognostic implications

Background: Q waves developed in the subacute and persisting into the chronic phase of myocardial infarction (MI) usually signify myocardial necrosis. However, the mechanism and significance of Q waves that appear very early in the course of acute MI (<6 h from onset of symptoms), especially if accompanied by ST elevation, are probably different. Hypothesis: This study assesses the prognostic implications of abnormal Q waves on admission in 2,370 patients with first acute MI treated with thrombolytic therapy <6 h of onset of symptoms. Results: Patients with abnormal Q waves in ≥2 leads with ST-segment elevation (n = 923) were older than patients without early Q waves (n = 1,447) (60.6 ±11.9 vs. 58.8 ±11.9 years, respectively; p = 0.0003), and had a greater incidence of hypertension (34.3 vs. 30.5% p = 0.05) and anterior MI (60.6 vs. 41.1 % p<0.0001). Time from onset of symptoms to therapy was longer in patients with Q waves upon admission (208 ± 196 vs. 183 ± 230 min; p = 0.01). Peak serum creatine kinase (2235 ± 1544 vs. 1622 ± 1536 IU; p<0.0001), prevalence of heart failure during hospitalization (13.8 vs. 7.0%, p<0.0002), hospital mortality (8.0 vs. 4.6% p = 0.02), and cardiac mortality (6.6 vs. 4.5%, p = 0.11) were higher in patients with anterior MI and with abnormal Q waves than in those without abnormal Q waves upon admission. There was no difference in peak creatine kinase, prevalence of heart failure, in-hospital mortality, and cardiac mortality between patients with and without abnormal Q waves in inferior MI. Multivariate regression analysis confirmed that mortality is independently associated with presence of Q waves on admission (odds ratio 1.61; 95% CI 1.04–2.49; p = 0.04 for all patients; odds ratio 1.65; 95% CI 0.97–2.83; p=0.09 for anterior wall MI. Conclusion: Abnormal Q waves on the admission electrocardiogram (ECG) are associated with higher peak creatine kinase, higher prevalence of heart failure, and increased mortality in patients with anterior MI. Abnormal Q waves on the admission ECG of patients with inferior MI are not associated with adverse prognosis.     

Prognosis for patients with initially suspected acute myocardial infarction in relation to presence of chest pain.

In all 4,232 patients admitted to a single hospital during a 21-month period due to initially suspected acute myocardial infarction (AMI), the prognosis and risk factor pattern were related to whether patients had chest pain or not. Symptoms other than chest pain that raised a suspicion of AMI were mainly acute heart failure, arrhythmia, and loss of consciousness. In 377 patients (9%) symptoms other than chest pain raised an initial suspicion of AMI. These patients developed a confirmed infarction during the first three days in hospital with a similar frequency (22%) as compared with patients having chest pain (22%). However, patients with "other symptoms" had a one-year mortality of 28% versus 15% for chest pain patients (p less than 0.001). Patients with "other symptoms" more often died in association with ventricular fibrillation and less often in association with cardiogenic shock as compared with chest pain patients. Among the 921 patients who developed early AMI, 64 (7%) had symptoms other than chest pain. They had a one-year mortality of 48% versus 27% for chest pain patients (p less than 0.001). We conclude that in a nonselected group of patients hospitalized due to suspected AMI, those with symptoms other than chest pain have a one-year mortality, which is nearly twice that of patients with chest pain.     

急性心肌梗死早期伴发二尖瓣关闭不全对患者预后影响

目的:探讨急性心肌梗死(AMI)患者伴发二尖瓣关闭不全(MR)的临床意义及预后。方法:将2年来我院收治的AMI患者145例分为MR组与no-MR组;根据梗死部位分为前壁AMI组与下壁AMI组,前、下壁各组又根据是否伴发MR分为:前壁MR组与前壁no-MR,下壁MR组与下壁no-MR组4个亚组。观察各组的临床情况与心血管事件。结果:MR组63例,占43.4%,与no-MR组相比,其年龄、左心室射血分数、终点心血管事件及随访期间心血管事件均差异具有统计学意义(P<0.05)。亚组间相比,前壁AMI-MR组与下壁AMI-MR组与相应的no-MR组比较终点心血管事件差异具有统计学意义,且该2组间随访期间临床心血管事件差异具有统计学意义(P<0.05);下壁AMI-MR组与no-MR组2组间的终点心血管事件差异具有统计学意义(P<0.05)。结论:AMI患者伴发MR提示预后不良,AMI患者伴有MR与梗死部位有关,且其部位与预后密切相关。     

Early and late Q wave regression in the setting of acute myocardial infarction

Abnormal Q waves after a myocardial infarction are not always an indicator of myocardial necrosis. In some cases these Q waves may disappear partially or completely in the evolution of the myocardial infarction. Five cases are described in whom complete Q wave regression and reappearance of R waves in the ECG leads corresponding to the affected area were observed. Q wave regression occurred early (hours) as well as late (months) after the myocardial infarction.


Keywords: myocardial infarction; Q wave regression     

Occurrence of angina pectoris prior to acute myocardial infarction and its relation to prognosis

In 917 patients with acute myocardial infarction (AMI) we evaluatedthe impact of previous angina pectoris on the prognosis. Thirty-fourpercent of the patients had chronic angina prior to AMI, and22% had angina pectoris of short duration. Patients with chronicangina pectoris differed from the remaining patients havinga more frequent previous history of AMI, diabetes mellitus,hypertension, and congestive heart failure. They less frequentlydeveloped a Q-wave AMI, and had smaller infarcts according tomaximum serum-enzyme activity as compared with the remainingpatients. They had a higher one-year mortality rate (36%) ascompared with those having angina pectoris of short duration(22%), and those with no angina pectoris (26%). Their reinfarctionrate was also higher (26%) as compared with that in the othertwo groups (15% and 9% respectively). In a multivariate analysisconsidering age, sex, clinical history, initial symptoms, initialelectrocardiogram and estimated infarct size, previous chronicangina pectoris was not an independent risk factor for death,but was independently associated with the risk of reinfarction(P<0.001) Among patients with a history of angina pectoristhe outcome was related to medication prior to onset of AMIand at discharge from hospital. Patients in whom beta-blockerswere prescribed at discharge had a one-year mortality of 13%as compared with 30% in the remaining patients (P<0.001).     

Bundle branch block in acute Q wave inferior wall myocardial infarction: A high risk subgroup of inferior myocardial infarction patients

The aim of this study was to determine the incidence and impactof right and left bundle branch block on the in-hospital, 5-yearand 10-year mortality of patients with acute inferior Q wavemyocardial infarction. A retrospective analysis of clinicalcharacteristics, hospital, 1-, 5-, and 10-year mortality of2215 consecutive patients with acute inferior Q wave myocardialinfarction hospitalized in 13 coronary care units in Israelwas performed Bundle branch block during acute Q wave inferior wall myocardialinfarction was present in 108 patients (4.9%), 85 of whom hadright and 23 left bundle branch block. Patients with bundlebranch block had more in-hospital complications than those without,irrespective of the site and time of appearance of the block.In addition, a trial fibrillation (19%), complete atrioventricularblock (21%) and congestive heart failure (45%) appeared morefrequently in patients with, than in those without, bundle branchblock (11%, 9% and 31%, respectively), and in-hospital and 5-yearmortality were higher in patients with the block (22%, 33%)than in those without it (13% and 23%, respectively). Bundle branch block emerged as an independent predictor of deathonly among patients with new right bundle branch block, andright bundle branch block emerged as an independent predictorfor the development of complete atrioventricular block (oddsratio 2.13; 90% confidence interval 1.39–3.28). However,hospital mortality among patients with inferior myocardial infarctionand complete atrioventricular block was virtually independentof bundle branch block (39% with vs 36% without bundle branchblock, respectively). Patients with inferior Q wave myocardial infarction and bundlebranch block comprise a high risk subgroup of patients witha complicated hospital course and increased hospital and long-termmortality.     

Slowed ST segment recovery despite early infarct artery patency in patients with Q waves at presentation with a first acute myocardial infarction. Implications of initial Q waves on myocyte reperfusion.

BACKGROUND: The presence of Q waves at presentation with a first acute myocardial infarction reflects a more advanced stage of the infarction process. When infarct-related artery patency (Thrombolysis in Myocardial Infarction 2 or 3 flow) is restored, resolution of ST segment elevation indicating successful myocyte reperfusion may differ according to how far the infarction process has progressed. METHODS AND RESULTS: In 144 patients with a first acute myocardial infarction treated with streptokinase in the first Hirulog Early Reperfusion Occlusion trial, information was obtained from continuous ST segment monitoring, the presenting electrocardiogram and early angiography performed at a median time of 99 min after the commencement of streptokinase (interquartile range 89-108 min). We determined how many patients had 50% ST recovery within 120 min and in how many cases it was sustained over 4h. In the 109 patients with patent infarct-related arteries, 50% ST recovery occurred in 95% of patients without vs 80% of those with initial Q waves (P=0.03), and sustained ST recovery occurred in 67% of patients without vs 47% of those with initial Q waves (P=0.03). On multivariate analysis including the time from symptom onset to streptokinase therapy, the presence of Q waves at presentation was the only predictor of failure to achieve 50% ST recovery (odds ratio 5.08, 95% confidence interval 1.29-20.01, P=0.02). TIMI 2 flow, as opposed to TIMI 3 flow, was the only predictor of failure to achieve stable ST recovery (odds ratio 2.63, 95% confidence interval 1.15-5.88,P =0.02). CONCLUSION: The presence of initial Q waves predicts slower and less complete ST recovery, reflecting reduced myocyte reperfusion, even in those with early infarct artery patency. These patients may be targeted for new therapeutic strategies to improve microvascular reperfusion.     

Characteristics and prognosis of patients with acute myocardial infarction in relation to occurrence of congestive heart failure

Congestive heart failure is one of the major symptoms accompanyingacute myocardial infarction (AMI). The study aimed to describethe occurrence, characteristics and prognosis of congestiveheart failure in AMI and to compare post-MI patients with andwithout congestive heart failure. The methods used includedbaseline characteristics, initial symptoms, electrocardiogram(ECG), mortality during hospitalization and one year follow-upin consecutive patients with AMI admitted to Sahlgrenska Hospital,Göteborg, Sweden. Congestive heart failure was observed in 51% of the cases. Patientswith congestive heart failure were older, more frequently hada history of previous cardiovascular disease, and, less frequentlyhad chest pain on admission to hospital. They had a higher occurrenceof life-threatening ventricular arrhythmias during initial hospitalization,and their mortality during one year follow-up was 39% as comparedto 17% in patients without congestive heart failure (P<0.001).This difference remained significant when correcting for differencesat baseline. Patients with severe congestive heart failure hada one year mortality of 47% vs 31% in patients with moderatecongestive heart failure (P<0.01). Signs and symptoms of congestive heart failure occur in everysecond patient admitted to hospital due to AMI, and indicatea bad prognosis, which is directly related to the severity ofcongestive heart failure.     

Prognosis in diabetics in whom the initial suspicion of acute myocardial infarction was not confirmed

For 2,058 consecutive patients hospitalized for suspected acute myocardial infarction (AMI) but in whom AMI was later ruled out, we describe the prognosis with particular emphasis on diabetics. In all, a previous history of diabetes mellitus occurred in 290 (14%) of the patients. Compared with nondiabetics, they had a longer delay time between onset of symptoms and arrival in hospital. During 1 year of follow-up, their mortality rate was 28% compared with 14% for nondiabetics (p < 0.001), and their reinfarction rate was 20% compared with 10% for nondiabetics. More diabetics died in association with a fatal myocardial infarction and more frequently had ventricular fibrillation preceding death. With the exception of re-infarction, no clear difference in terms of morbidity was observed between the two groups. We conclude that the prognosis in diabetics in whom AMI is ruled out is poor, with between one-quarter and one-third not surviving 1 year.     

缺血预适应对急性心肌梗死Q—T离散度及室性心律失常的影响

目的探讨缺血预适应对急性心肌梗死Q-T间期离散度及室性心律失常的影响.方法根据318例首次急性心肌梗死患者发病前48h内是否发生心绞痛,分为缺血预适应组(186例)和无缺血预适应组(132例),另取健康人11l例作为对照组,测定每例校正Q-T间期离散度(Q-Tcd).结果无缺血预适应组Q-Tcd(70.47±12.05ms)明显大于缺血预适应组(55.96±10.4lms,P＜0.01),缺血预适应组明显大于对照组(42.47±9.17ms,P＜0.01).缺血预适应组室性心动过速、心室颤动及猝死的发生率明显低于无缺血预适应组(P均＜0.01).结论缺血预适应可明显减小急性心肌梗死时的Q-T离散度,降低室性心律失常和猝死的发生率.     

Prognosis following acute myocardial infarction in patients with ST-T abnormalities on electrocardiograms obtained before myocardial infarction

BACKGROUND: Many studies have examined the relationship between prognosis after myocardial infarction (MI) and electrocardiographic (ECG) findings at the time of or after the onset of MI. However, little work has been done concerning the association between ECG findings obtained before the onset of MI (pre-MI) and the prognosis after MI. HYPOTHESIS: The study was undertaken to determine whether ST-T segment and T-wave morphology on pre-MI ECGs provides useful information for prognosis after acute MI. METHODS: Pre-MI ECGs of 212 patients recorded within the 6-month period before MI were studied for the presence of high-voltage R waves, ST-segment depression, and negative T waves. The Kaplan-Meier method and multivariate analysis were used to determine the relationship between these ECG findings and in-hospital cardiac death. RESULTS: In-hospital cardiac death occurred in 32 (15.1%) patients. The in-hospital mortality rate was 38.5% (5/13) for the patients with high-voltage R waves, 54.5% (6/11) for patients with ST-segment depression, and 45.6% (15/33) for patients with negative T waves. The in-hospital mortality rate was 13.6% (27/199) for patients without high-voltage R waves, 12.9% (26/201) for patients without ST-segment depression, and 9.5% (17/179) for those without negative T waves. Multivariate analysis identified age and negative T waves as independent risk factors for cardiac death, with a hazard ratio for negative T waves of 3.1. CONCLUSION: Negative T waves on pre-MI ECGs represent an independent predictor of in-hospital cardiac death in patients with MI.     

Significance of the Q wave in acute myocardial infarction

Acute myocardial infarction may be associated with the development of Q waves on the electrocardiogram (ECG), or with changes limited to the ST segment or T wave. The ECG changes do not accurately differentiate transmural from nontransmural infarction. However, the presence or absence of a Q wave does correlate with some aspects of the clinical course of patients after myocardial infarction, and is therefore of prognostic value. Q-wave infarctions are more likely to be complicated by congestive heart failure during hospitalization. The in-hospital mortality is also higher after a Q-wave infarction than after a non-Q infarction. Both of these findings are probably due to the association of a Q wave with a larger mass of infarcted myocardium. The long-term mortality, however, is the same for Q-wave and non-Q-wave infarctions. This is probably due to an increased late mortality after non-Q infarctions, related in part to a higher rate of reinfarction. The differences between Q-wave and non-Q-wave infarctions are not due to obvious differences in extent and location of coronary artery obstructions. However, there may be differences in the collateral circulation, with more extensive collaterals associated with non-Q infarcts. Appreciation of the prognostic significance of the ECG changes in acute myocardial infarction may help direct the evaluation and management of the patient after myocardial infarction.     

Ten-year mortality amongst patients with a very small or unconfirmed acute myocardial infarction in relation to clinical history, metabolic screening and signs of myocardial ischaemia

AIM: To evaluate the long-term prognosis amongst patients with a very small or unconfirmed acute myocardial infarction (AMI) in relation to clinical history, metabolic screening and signs of myocardial ischaemia at exercise test. METHODS: Patients with a very small or unconfirmed AMI, aged < 76 years, were selected and given a clinical evaluation, metabolic screening and checked for ischaemia at an exercise test 4 weeks after admittance. The 10-year mortality was related to age, sex, clinical history, body weight, serum (S) cholesterol, S-triglycerides, S-gammaglutamyltranspeptidase (GT), S-glucose and various indices of myocardial ischaemia at exercise test. RESULTS: In all, 714 patients participated in the evaluation. The median age was 63 years and 33% were women. The overall 10-year mortality was 33%. In univariate analysis, the following factors appeared as risk indicators for death: age (P < 0.0001), a history of previous AMI (P < 0.0001), angina pectoris (P < 0.001), diabetes mellitus (P < 0.0001), congestive heart failure (P < 0.0001), smoking (P = 0.030), S-triglycerides (P < 0.0001), S-gamma GT (P < 0. 0001) and S-glucose (P < 0.0001). In multivariate analysis, the following remained as independent risk indicators for death: age (P < 0.0001), S-gamma GT (P < 0.0001), previous AMI (P < 0.0001), smoking (P < 0.0001) and S-glucose (P = 0.010). CONCLUSION: Amongst patients with a very small or a unconfirmed AMI, factors reflecting their clinical history, including age, a history of AMI and current smoking, as well as factors reflecting their metabolic status, including S-gamma GT and S-glucose, were important predictors for the long-term outcome.     

Predictors of spontaneous predischarge ischemia following acute myocardial infarction.

To determine if the occurrence and the consequences of spontaneous predischarge postinfarction ischemia could be predicted early after hospital admission, a consecutive series of patients with acute myocardial infarction was studied and followed for 3 years. No patient was treated by thrombolysis. Spontaneous predischarge ischemia was defined as angina that occurred at rest before hospital discharge, at least 3 days after the acute event, and that was accompanied by electrocardiographic changes, but not by an increase in cardiac enzymes. Patients who died within the first 3 days were excluded from analysis. Among the 943 patients who survived at least 3 days, 165 (17.5%) had spontaneous ischemia before discharge. They had a higher 1-year post-hospital mortality (16 vs. 10%), but did not have significantly higher total 3-year mortality rates. Four independent, early available variables predictive of the occurrence of spontaneous ischemia were selected from a stepwise logistic discriminant analysis: history of angina before infarction, non-Q-wave infarct, absence of smoking, and higher age. Among the 165 patients with spontaneous ischemia, 3 independent variables predictive of 3-year mortality were selected stepwise: left ventricular function score, history of previous infarction, and absence of smoking.     

Q波型与非Q波型心肌梗死患者的近期预后

为探讨心肌梗死有无Ｑ波对近期预后的影响，随诊７８例无Ｑ波型心肌梗死（ＮＱＭＩ）和２２４例Ｑ波型心肌梗死（ＱＭＩ）患者，随诊以死亡为终点或随诊至患病后６个月。两组相比：１．院内死亡率分别为２．５６％和１３％（Ｐ〈０．０１），２．Ｋａｐｌａｎ－Ｍｅｉｅｒ曲线６个月生存率分别为９４．９％和８１．５％（时距检验Ｐ〈０．０１），６个月无心脏再发缺血事件发生分别为８５．５％和６９．１％（时距检验Ｐ〈０．０１）     

血B型钠尿肽与急性心肌梗死早期介入治疗预后的关系

目的:探讨急性心肌梗死(AMI)患者早期血运重建后,血B型钠尿肽(BNP)浓度的变化及其对患者临床预后的评价。方法:入选住院治疗的首次ST段抬高AMI112例患者:其中男74例,女38例,年龄36~88(62.8±12.6)岁,测定其入选时,入院后24h和7d的血BNP;根据发病6h内梗死相关血管开通情况分为6h开通组(69例)和6h未开通组(43例);入院后7d内行超声心动图检查,记录左室舒张末期容积指数(LVED-VI)、左室射血分数(LVEF)等;出院后随访24个月,记录其主要临床终点事件(心源性死亡、新发或恶化的心力衰竭、再发非致死性心肌梗死)。结果:2组AMI患者血BNP浓度在入院时无显著性差异,第24h及第7天,6h未开通组血BNP浓度明显较高(P<0.01)。2年内6h开通组与6h未开通组无事件生存率分别为85.50%和62.87%(P=0.001);LogisticRank分析显示6h未开通组与6h开通组相比2年无事件生存率低(P=0.003),BNP等指标预测AMI经直接介入治疗2年内心血管不良事件的ROC曲线显示,入院后24h的血BNP(BNP2)可作为预测2年内心血管不良事件的指标。结论...     

微量白蛋白尿对非糖尿病急性心肌梗死预后的意义

目的：探讨微量白蛋白尿（MA）与非糖尿病急性心肌梗死（NDM－AMI）患者预后的关系。方法：收集1996年10月－2001年5月期间肾功能处于代偿期的NDM－AMI住院病人43例，分MA阳性组和MA阴性组，对入院后心肌梗死面积大小（心电图、心肌酶谱分析）、冠状动脉造影结果、AMI后3月心内绞痛、再发心肌梗死，心衰发生率及死亡率进行统计学分析。结果：NDM－AMI患者MA阳性占53．49％，冠状动脉造影提示MA阳性组冠状动脉粥样硬化病变程度较MA阴性组广泛和严重；EKG和血清心肌酶谱显示MA阳性组心肌梗死面积大于MA阴性组（P＜0．05）；两组AMI后3月内心绞痛、再发心肌梗死、心衰发生率和死亡率具有显著性差异（P＜0．01）。结论：MA阳性提示NMD－AMI患者体内广泛性血管病变，且近期预后不良。     

Does the electrocardiographic presence of Q waves influence the survival of patients with acute myocardial infarction?

AIMS: To compare the outcome of short- and long-term survival of patients with Q wave vs non-Q wave myocardial infarction. METHODS: A total of 6676 patients with acute myocardial infarction were enrolled on the TRAndolapril Cardiac Evaluation (TRACE) register between 1990 and 1992. Medical history, electrocardiographic diagnosis of Q wave and non-Q wave myocardial infarction, echocardiographic estimation of left ventricular systolic function determined as wall motion index, infarct complications, and survival were documented. The factors influencing the postmyocardial infarction outcome of these patients were studied after 30 days and after 8 years of follow-up, respectively. RESULTS: Cox proportional-hazard models demonstrated that the electrocardiographic Q waves had significant influence on survival during the first 30 days [risk ratio 1.4 (95% confidence limits 1.2-1.7)] but no influence thereafter [1.0 (0.9-1.1)]. The result was the same in univariate and multivariate analyses. Subgroup analysis defined by age, sex, wall motion index, presence of congestive heart failure, diabetes mellitus, arterial hypertension, subsequent myocardial infarctions and use of thrombolytic therapy did not disclose importance of Q waves on mortality. CONCLUSION: The electrocardiographic presence of Q waves is associated with increased mortality during the initial 30 days after a myocardial infarction, but has no influence thereafter.