Coronary surgery after recurrent myocardial infarction: progress of a trial comparing surgical with nonsurgical management for asymptomatic patients with advanced coronary disease

Coronary artery bypass grafting versus medical therapy in patients with stable coronary artery disease: An individual patient data pooled meta-analysis of randomized trials

OBJECTIVES

It is unclear whether coronary artery bypass grafting (CABG) improves survival compared with medical therapy (MT) in patients with stable coronary artery disease (CAD). The aim of this analysis was to perform an individual-patient data-pooled meta-analysis of contemporary randomized controlled trials that compared CABG and MT in patients with stable CAD.

METHODS

A systematic search was performed in January 2021 to identify randomized controlled trials enrolling adult patients with stable CAD, randomized to CABG or MT. Only trials using at least aspirin, beta-blockers, and statins in the MT arm were included. Individual patient data were obtained from all eligible studies and pooled. The primary outcome was all-cause mortality.

RESULTS

Four trials involving 2523 patients (1261 CABG; 1262 MT) were included with a median follow-up of 5.6 (4.0-9.2) years. CABG was associated with increased risk of all-cause mortality within 30 days (hazard ratio [HR], 4.81; 95% confidence interval [CI], 1.95-11.83) but subsequent reduction in the long-term risk of death (HR, 0.79; 95% CI, 0.69-0.89). As such, the cumulative 10-year mortality rate was lower in patients treated with CABG compared with MT (45.1% vs 51.7%, respectively; odds ratio, 0.70; 95% CI, 0.58-0.85). Age and race were significant treatment effect modifier (interaction P = .003 for both).

CONCLUSIONS

In patients with stable CAD, initial allocation to CABG was associated with greater periprocedural risk of death but improved long-term survival compared with MT. The survival advantage for CABG became significant after the fourth postoperative year and was particularly pronounced in younger and non-White patients.

Role of surgical revascularization in diabetic patients with coronary artery disease

Diabetes is a well-known risk factor for morbidity and mortality associated with coronary artery disease. Currently, diabetics represent approximately a quarter of patients requiring coronary revascularization in the USA. The purpose of this article is to review and analyze the available data in surgical revascularization of diabetic patients with coronary artery disease. The review will also examine new developments in myocardial revascularization and assess their probable impact on the long-term outcome of diabetic patients.

Revascularization of left main coronary artery disease

Coronary artery disease with left main stenosis is associated with the highest mortality of any coronary lesion. Studies in the 1970s and 1980s comparing coronary artery bypass grafting (CABG) and medical therapy showed a significant survival benefit with revascularization. In the angioplasty era, initial experience with percutaneous intervention was associated with poor clinical outcomes. As a result, percutaneous coronary intervention (PCI) was restricted to patients who were considered inoperable, or those with prior CABG with a functional graft to the left anterior descending or circumflex artery ("protected left main disease"). With the introduction of drug-eluting stents, there are new studies demonstrating comparable survival in patients who were revascularized using PCI and CABG, although percutaneous revascularization is associated with a higher rate of repeat revascularization. In the SYNTAX (Synergy between PCI with Taxus and Cardiac Surgery) trial, the combined incidence of death, myocardial infarction, and stroke was similar between the CABG and PCI groups; however, the stroke rate was higher in the CABG group. The degree and extent of disease as defined by the SYNTAX scoring system has allowed for stratification of risk and improved assignment of patients with left main stenosis to either PCI or CABG.

The impact of revascularization on mortality in patients with nonacute coronary artery disease

BACKGROUND

Although early revascularization improves outcomes for patients with acute coronary syndromes, the role of revascularization for patients with nonacute coronary artery disease is controversial. The objective of this meta-analysis was to compare surgical or percutaneous revascularization with medical therapy alone to determine the impact of revascularization on death and nonfatal myocardial infarction in patients with coronary artery disease.

METHODS

The Medline and Cochrane Central Register of Controlled Trials databases were searched to identify randomized trials of coronary revascularization (either surgical or percutaneous) versus medical therapy alone in patients with nonacute coronary disease reporting the individual outcomes of death or nonfatal myocardial infarction reported at a minimum follow-up of 1 year. A random effects model was used to calculate odds ratios (OR) for the 2 prespecified outcomes.

RESULTS

Twenty-eight studies published from 1977 to 2007 were identified for inclusion in the analysis; the revascularization modality was percutaneous coronary intervention in 17 studies, coronary bypass grafting in 6 studies, and either strategy in 5 studies. Follow-up ranged from 1 to 10 years with a median of 3 years. The 28 trials enrolled 13,121 patients, of whom 6476 were randomized to revascularization and 6645 were randomized to medical therapy alone. The OR for revascularization versus medical therapy for mortality was 0.74 (95% confidence interval [CI], 0.63-0.88). A stratified analysis according to revascularization mode revealed both bypass grafting (OR 0.62; 95% CI, 0.50-0.77) and percutaneous intervention (OR 0.82; 95% CI, 0.68-0.99) to be superior to medical therapy with respect to mortality. Revascularization was not associated with a significant reduction in nonfatal myocardial infarction compared with medical therapy (OR 0.91; 95% CI, 0.72-1.15).

CONCLUSION

Revascularization by coronary bypass surgery or percutaneous intervention in conjunction with medical therapy in patients with nonacute coronary artery disease is associated with significantly improved survival compared with medical therapy alone.

Prevalence of factor V Leiden and prothrombin variant G20210A in patients age <50 years with no significant stenoses at angiography three to four weeks after myocardial infarction

OBJECTIVES

We sought to determine the frequencies of factor V Leiden and prothrombin variant G20210A in patients age <50 years with no significant coronary stenoses three to four weeks after myocardial infarction (MI).

BACKGROUND

Factor V Leiden and prothrombin variant G20210A occur frequently in patients with venous thromboembolism. However, the contribution of these mutations to the development of MI requires clarification.

METHODS

The frequencies of factor V Leiden and prothrombin variant G20210A were determined in 41 patients age <50 years who had "normal" or "near normal" coronary arteries (no stenosis >50%) at angiography three to four weeks after MI (the study group) and compared with those in 114 patients who had at least one angiographic stenosis >50% after MI (the control group). Patients age > or =50 years with, or without, stenoses were also studied.

RESULTS

The frequency of factor V Leiden was 14.6% in patients age <50 years in the study group compared with 3.6% in patients in the control group (odds ratio [OR] 4.7 [95% confidence interval (CI) 1.3-17.7], p = 0.02). The frequency of the prothrombin variant G20210A was 7.3% in the study group compared with 1.8% in the control group (OR 4.4 [95% CI 0.7-27.5], p = 0.12). One or both mutations were present in 8 of the 41 patients (19.5%) age <50 years in the study group compared with 6 of the 114 patients (5.5%) in the control group (OR 4.4 [95% CI 1.4-13.5], p = 0.01). In all 271 patients (irrespective of age) with normal arteries, the frequency of factor V Leiden was 11.7% (7/60) compared with 4.3% (9/211) in patients with at least one >50% stenosis (OR 2.9 [95% CI 1.1-8.3], p = 0.04), and the frequency of prothrombin variant G20210A was 6.7% (4/60) compared with 1.4% (3/211) (OR 4.9 [95% CI 1.1-22.8], p = 0.04), respectively.

CONCLUSIONS

The frequencies of factor V Leiden and/or prothrombin variant G20210A are increased in patients age <50 years with normal or near normal coronary arteries after MI.

Effect of coronary artery bypass graft surgery on survival: overview of 10-year results from randomised trials by the Coronary Artery Bypass Graft Surgery Trialists Collaboration

We carried out a systematic overview using individual patient data from the seven randomised trials that have compared a strategy of initial coronary artery bypass graft (CABG) surgery with one of initial medical therapy to assess the effects on mortality in patients with stable coronary heart disease (stable angina not severe enough to necessitate surgery on grounds of symptoms alone, or myocardial infarction). 1324 patients were assigned CABG surgery and 1325 medical management between 1972 and 1984. The proportion of patients in the medical treatment group who had undergone CABG surgery was 25% at 5 years, 33% at 7 years, and 41% at 10 years: 93.7% of patients assigned to the surgery group underwent CABG surgery. The CABG group had significantly lower mortality than the medical treatment group at 5 years (10.2 vs 15.8%; odds ratio 0.61 [95% CI 0.48-0.77], p = 0.0001), 7 years (15.8 vs 21.7%; 0.68 [0.56-0.83], p < 0.001), and 10 years (26.4 vs 30.5%; 0.83 [0.70-0.98]; p = 0.03). The risk reduction was greater in patients with left main artery disease than in those with disease in three vessels or one or two vessels (odds ratios at 5 years 0.32, 0.58, and 0.77, respectively). Although relative risk reductions in subgroups defined by other baseline characteristics were similar, the absolute benefits of CABG surgery were most pronounced in patients in the highest risk categories. This effect was most evident when several prognostically important clinical and angiographic risk factors were integrated to stratify patients by risk levels and the extension of survival at 10 years was examined (change in survival -1.1 [SE 3.1] months in low-risk group, 5.0 [4.2] months in moderate-risk group, and 8.8 [5.4] months in high-risk group; p for trend < 0.003). A strategy of initial CABG surgery is associated with lower mortality than one of medical management with delayed surgery if necessary, especially in high-risk and medium-risk patients with stable coronary heart disease. In low-risk patients, the limited data show a non-significant trend towards greater mortality with CABG.

First myocardial infarction in patients under 60 years old: the role of exercise tests and symptoms in deciding whom to catheterise

OBJECTIVE

To determine the role of exercise tests and assessment of angina in the detection of potentially threatening disease in young patients with infarcts.

DESIGN

Elective readmission of patients at a mean (SD) of 60 (30) days after acute myocardial infarction for assessment of angina, treadmill exercise tests, and cardiac catheterisation.

SETTING

Cardiology department of a teaching hospital.

PATIENTS

186 consecutive survivors, aged under 60 years and discharged from the coronary care unit after a first myocardial infarction.

MAIN OUTCOME MEASURES

Coronary arteriography, presence of angina, result of exercise tests, and referral for revascularisation.

RESULTS

31% of patients had either two vessel disease (with proximal left anterior descending involvement), three vessel disease, or left main stem disease. 49% of all patients had angina. Of the 173 patients who had an exercise test 34% had 1 mm and 24% had 2 mm of exercise induced ST depression. Thirty percent had no angina and a negative exercise test: after a mean (SD) follow up of 16 (4) months none of this symptom free sub-group had died, had experienced a further myocardial infarction, or had been referred for revascularisation. 79% of patients with either two vessel disease (with proximal left anterior descending involvement), three vessel disease, or left main stem disease had either angina or a 1 mm ST depression during the exercise test.

CONCLUSION

Patients without cardiac pain after myocardial infarction and without ST changes during an exercise do not need arteriography.

Management of the patient following coronary thrombolysis

Myocardial salvage can be maximized by the early institution of thrombolytic therapy and aspirin. Certain patients may benefit from the administration of intravenous heparin, beta blockers, or nitroglycerin. The routine use of percutaneous transluminal coronary angioplasty (PTCA) or calcium-channel blockers does not appear to be warranted. Recurrent myocardial ischemia should be vigorously treated with medical therapy and there may be value in cardiac catheterization, followed by PTCA or bypass surgery, depending upon the extent of myocardium at risk and the underlying coronary anatomy. Long-term morbidity and mortality may be reduced by instituting aspirin and beta blockers as well as by modifying risk factors. There is no evidence for the long-term benefit from any calcium-channel blocker. Oral anticoagulation may be warranted in those patients with a mural thrombus, congestive heart failure, or atrial fibrillation. ACE inhibitors may be of value in the presence of left ventricular dysfunction and certainly in the presence of symptomatic congestive heart failure. Antiarrhythmic therapy is generally indicated only for symptomatic or life-threatening arrhythmias. Residual myocardial ischemia should be sought by exercise testing, and those patients with poor exercise tolerance generally warrant cardiac catheterization in consideration for revascularization.

Selection and evaluation of empirical research in technology assessment

Technology assessment involves application of the scientific method to the practice of medicine. Finding all of the assessment reports in a given field is not an easy task. Proper evaluation of those assessments requires the conduct of a prospective experiment in which the sources and results are blinded when the choice is made of papers to exclude and to include, and the process should be carried out in duplicate. There are several available data bases for carrying out the search, but because of indexing problems they should be supplemented by reference to the bibliographies of pertinent published articles. Clinical trials included in meta-analyses should be graded by quality and thus facilitate sensitivity analyses. Attention must be paid to the possibility of publication bias. Finally, the advent of meta-analysis makes it desirable to begin randomized controlled trials in areas of uncertainty, even when there is no possibility that individual investigators will encounter enough patients to draw valid conclusions.

Psychosomatic aspects of coronary artery bypass graft surgery. A prospective study of 101 male patients

101 consecutive male patients were examined by means of clinical interviews and depression, anxiety, personality, psychometric and life stress tests. The examinations took place preoperatively, on the 9th postoperative day (average) and 7.5 months after surgery. The mean age of the patients was 52.2 years and the mean duration of CHD was 6.7 years. Prior to surgery 77% had experienced myocardial infarction and 85% belonged to NYHA class III or IV. 74% had a 3-vessel disease. When the NYHA classification was used as criterion for rehabilitation the result was excellent. Postoperatively 80% belonged to NYHA class I or II. Hospital mortality rate was 4% and one patient died from myocardial infarction prior to the final follow-up. Preoperatively 17% of the study group were working. 87% of the patients experienced negative effects on work life, caused by CHD. Postoperatively 33% worked regularly. The postoperative work situation correlated with the duration of preoperative unemployment (p less than 0.0001), the patient's own opinion about work return (willingness/unwillingness to return to work) (p less than 0.01), as well as with the amount of negative life stress experienced preoperatively (p less than 0.01). Only 13% of the series experienced positive effects on work life, caused by CABG surgery. The majority of the patients had experienced negative effects on social and economic life (51%), as well as on sexual life (70%), caused by CHD. After surgery improvements were noted by 36% on social life and by 27% on sexual life. 15% experienced impairment of sexual life postoperatively. According to the Beck Depression Inventory 29% showed depression preoperatively, and 10% postoperatively. The difference is significant (p less than 0.0001). Clinically the figures tended to be higher. The same tendency holds for anxiety scores as measured by the Hamilton anxiety scale. The incidence of postoperative psychoses was 35%. Higher age (p less than 0.01) and/or absence of psychosomatic diseases (p less than 0.05) correlated with higher frequency of psychoses. Even though cardiological rehabilitation according to the NYHA classification was excellent, 22% of the series did not think their expectations were fulfilled. Psychic and social rehabilitation was in several aspects unsatisfactory, and the patients did not seem prepared for this. The importance to consider rehabilitation from a psychosomatic standpoint is clearly shown. To predict the result of rehabilitation preoperatively is not possible.

Myocardial infarct expansion, infarct extension, and reinfarction: pathophysiologic concepts

Infarct expansion and infarct extension are events early in the course of myocardial infarction with serious short- and long-term consequences. Infarct expansion, disproportionate thinning, and dilatation of the infarct segment probably begin within hours of acute infarction and usually reach peak extent within seven to 14 days. Clinical data suggest that infarct expansion occurs in approximately 35% to 45% of anterior transmural myocardial infarctions and to a lesser extent in infarctions at other sites. Although expansion usually develops in large infarcts, the extent of transmural necrosis rather than absolute infarct size predicts its occurrence. Expansion has an adverse effect on infarct structure and function for several reasons. Functional infarct size is increased because of infarct segment lengthening, and expansion results in over-all ventricular dilatation. Thus, patients with expansion of an infarct have poorer exercise tolerance, more congestive heart failure symptoms, and greater early and late mortality than those without expansion. Infarct rupture and late aneurysm formation are two additional structural consequences of infarct expansion. Experimental and clinical data suggest that the incidence and severity of expansion can be modified by interventions. Increased ventricular loading conditions and steroidal and nonsteroidal antiinflammatory agents make expansion more severe. Reperfusion of the infarct segment and pharmacologic interventions that decrease ventricular afterload lessen the severity of expansion. Previous myocardial infarction and preexisting ventricular hypertrophy may also limit the development of infarct expansion. Infarct extension is defined clinically as early in-hospital reinfarction after a myocardial infarction. The pathologic finding of infarct extension is necrotic and healing myocardium of several different recent ages within the same vascular territory. Although this pathologic criterion usually cannot be verified, studies employing invasive and noninvasive assessment of patients with early reinfarction provide evidence that the new myocardial injury is usually in the same vascular risk region as the original infarction. A variety of different criteria have been applied in the clinical diagnosis of infarct extension, and this has resulted in a large range of estimated frequencies from under 10% to as high as 86%. High estimates are found in studies using one or two nonspecific criteria such as ST segment shift or reelevation of total CK. The lowest rates have been found when combinations of criteria are used.(ABSTRACT TRUNCATED AT 400 WORDS)

Clinical course and risk stratification of myocardial infarct survivors with three-vessel disease

Prevalence of three-vessel disease was prospectively analyzed in a series of 462 consecutive infarct survivors aged 60 years or less. Eighty-seven percent (403) of the patients were catheterized within one month of the acute event, and were followed for a mean of 43 months (range 21 to 69). Three-vessel disease was present in 96 cases (24%) and these patients form the study population. The primary goals of this study were to determine the prevalence of three-vessel disease and to identify predictors of survival and new coronary events among this subset of infarct survivors. During follow-up, 15 patients died, 17 had a recurrent nonfatal infarction, and 54 developed angina (4-year probability of each cardiac event being 0.20, 0.22, and 0.59, respectively). Cox's stepwise multivariate analysis identified the ejection fraction (EF) as the only predictor of survival (p less than 0.001). No predictors for nonfatal ischemic events were found among the independent variables considered. Patients were stratified in risk categories according to the EF. Four-year probability of survival was 1.0 in participants with EF = greater than 50% (n = 23), 0.77 for those with EF = 21% to 49% (n = 66), and 0.22 in patients with more severe left ventricular dysfunction, EF = less than 20% (n = 7). Probability of occurrence of nonfatal reinfarction or angina was similar in the three risk categories. Thus, our results indicate that a normal ejection fraction is found in 25% of infarct survivors with three-vessel disease, and that this subset of patients has a low incidence of early and intermediate range coronary events.

Prognostic significance of asymptomatic coronary artery disease

Prognosis in the various forms of asymptomatic coronary artery disease is not precisely defined but available data suggest that it may not be as benign as previously thought. This is especially true in patients with silent myocardial ischemia, 3-vessel disease and poor exercise tolerance, because many of these patients may go on to sudden death or myocardial infarction. It is also true in patients with silent myocardial infarctions, because prognosis in this type of myocardial infarction is similar to that of patients with symptomatic infarctions.

Value of programmed stimulation and exercise testing in predicting one-year mortality after acute myocardial infarction

The ability of programmed ventricular stimulation and exercise testing to predict 1-year mortality after acute myocardial infarction (AMI) was investigated in 228 clinically well survivors of AMI. Patients with inducible ventricular tachycardia (VT) or ventricular fibrillation (VF) had a higher mortality rate than those without inducible arrhythmias (26% vs 6%, p less than 0.001). Exercise-induced ST-segment change of 2 mm or more was associated with a higher mortality rate than ST change of less than 2 mm (11% vs 4%, 0.05 less p less than 0.10). Of patients who had both tests, 62% had no inducible ventricular tachycardia or ventricular fibrillation and ST change of less than 2 mm, and only 1% died during the first year. Thus, in clinically well survivors of AMI, programmed stimulation is a powerful predictor of first-year mortality; programmed stimulation and exercise testing together predict virtually all deaths within the first year, and they can identify a large group of patients with a very low mortality rate.

The place of coronary artery bypass surgery: an appraisal

The enthusiasm for performing coronary artery bypass graft (CABG) surgery in Australia is increasing. The results of a number of careful trials which have compared surgical with medical treatment have now appeared. While there is agreement on both the increased survival provided by CABG surgery in those with left main coronary artery stenosis and the relief of symptoms in patients in whom medical therapy has failed to control severe angina, there is debate about the value of surgery in other types of disease. With improvements in medical therapy, the most recent trials have failed to show a significant overall survival benefit from surgery, although it is generally considered that surgery can relieve angina and that, in at least some groups of persons with stenosis of all three main coronary vessels (triple-vessel disease), surgery may prolong life. Alternative methods of prolonging survival among people with ischaemic heart disease include the reduction of risk factors (such as hypertension, raised blood cholesterol levels and cigarette smoking), as well as treating patients with beta-blocking agents after a myocardial infarction. We suggest it is likely that a combination of these approaches could be more effective in terms of lives saved than is CABG and may be less expensive. The current expansion of CABG surgery in Australia should be viewed in this light.

Current status of coronary artery bypass grafting for coronary artery atherosclerosis

Coronary artery bypass grafting has now undergone 18 years of proven benefit in the treatment of myocardial ischemic disease. The technique of CABG has been further extended to other situations in which myocardial blood supply is threatened, such as cardiac trauma, aneurysms of coronary arteries, and congenital lesions. The emphasis in choosing CABG over medical therapy in 1985 should be preservation of myocardium at jeopardy of infarction as well as relief of angina. Proximal stenoses in vessels subserving viable muscle that is ischemic at rest or with minimal exercise should be treated with reperfusion by angioplasty or CABG to prevent further injury. After infarction occurs and ventricular function is impaired, CABG is also necessary to preserve remaining myocardium at jeopardy. Such an aggressive approach seems warranted with today's excellent surgical results. Long-term results have also improved, as more attention has been paid to saphenous vein graft preparation, use of mammary artery grafts, complete revascularization, use of antiplatelet agents, control of spasm, and identification of hypercoagulable states that may require sodium warfarin (Coumadin). Angioplasty of vein grafts and distal anastomoses also appears promising to help extend the results of initial CABG. Figure 1 is our recommended approach for the treatment of coronary atherosclerosis.

Relation and independence of angina pectoris and sudden death in persons with coronary atherosclerotic heart disease

Angina is an important though relatively insensitive and nonspecific predictor of the presence of significant coronary occlusive disease. If angina is present, there is a high probability of significant coronary atherosclerosis. However, the lack of angina, even with vigorous exertion, does not imply absence of severe and potentially lethal amounts of coronary stenosis because a high percent of patients who have had sudden cardiac arrest or myocardial infarction have not had prior angina pectoris. In many studies that carefully and specifically examined the prognostic importance of angina in relation to other variables, neither the presence of angina nor its severity was of prognostic significance, although a few studies suggested that the unstable form of angina may have unfavorable prognostic significance independent of the state of left ventricular function or the severity of coronary atherosclerosis. Thus, it would not appear to be wise to base individual or national decisions aimed at reducing the likelihood of death from coronary disease primarily on the presence or absence of angina pectoris.

Submaximal exercise testing early after myocardial infarction. Difficulty of predicting coronary anatomy and left ventricular performance

Impaired left ventricular function and extensive coronary artery disease are important determinants of prognosis after acute myocardial infarction. The ability of clinical and predischarge submaximal exercise test variables to predict multivessel coronary artery disease and impaired left ventricular function was assessed in 62 survivors of acute myocardial infarction. Abnormal exercise blood pressure response and short exercise performance were predictors of multivessel disease, but exercise induced ST segment changes and clinical variables were not. Q wave infarction, high grade Killip classification, and exercise induced ST segment elevation predicted statistically significant impairment of resting left ventricular function, whereas other clinical and exercise test variables did not. Exercise induced ST segment changes were therefore of little value in detecting extensive coronary disease, although exercise induced ST elevation was an indicator of poor resting left ventricular function. Although abnormal exercise haemodynamics may detect extensive coronary artery disease, other physiological markers of reversible myocardial ischaemia are probably necessary to plan optimal management in these patients.

Prognosis of cardiac disease in the ambulant patient

Much investigation and treatment in cardiac practice is based on the assumption that unexpected death is common in cardiac patients. The validity of this assumption was examined in 636 of 669 (95.1%) consecutive ambulant patients. During the period from 1978 to 1981, inclusive, 16 (3.9%) of the 407 men (median age, 52 years) and six (2.6%) of the 229 women (median age, 54 years) died. Nineteen of these 22 patients died of cardiac causes; most of these were elderly (average age, 68.5 years), had advanced cardiac disease for many years before their death, and complained of breathlessness at the initial interview. None of these deaths was unexpected. It is concluded that unexpected death is relatively uncommon, even in cardiology practice. The intensive diagnostic and therapeutic regimens directed at younger patients with cardiomyopathy and coronary disease who do not complain of breathlessness are unlikely to have an appreciable impact on mortality.

Submaximal exercise testing early after myocardial infarction. Prognostic importance of exercise induced ST segment elevation

Seventy four patients (66 men, eight women; mean age 54.3 years) underwent submaximal exercise testing 7-23 days (mean 10.7) after acute myocardial infarction. Follow up was a mean period of 11.3 months. When compared with patients with no exercise induced abnormality, ST segment elevation, ST shift (depression or elevation or both), ST depression, inability to complete five metabolic equivalents, and inadequate blood pressure response to exercise were predictive of subsequent cardiac events (cardiac death, left ventricular failure, recurrent myocardial infarction, angina). When the presence or absence of specific variables was assessed, only ST elevation and ST shift predicted subsequent cardiac events. The presence of exercise induced ST elevation was the only exercise test variable which predicted cardiac death. ST segment elevation was, therefore, the exercise induced abnormality which best predicted the risk of future complications.

Assessment of the impact of coronary artery surgery on mortality after recovery from myocardial infarction

Death rates over a nine year period were studied in 1,232 survivors of myocardial infarction. From 1973 to 1981, the 29 to 365 day case fatality rate in 28 day survivors dropped from 13.3% to 3.2%. This down-trend in case fatality was highly significant, averaging 14.3% in each year. After adjustment for changes in age and severity of infarction, using a prognostic score derived from the Perth Coronary Register (the PCR score), the estimated decline was still 12.2% in each year. During the nine years, the rate of coronary surgery in the post-infarction year rose from 1.5% to 12.0%. Overall, the surgically treated cases had a lower case fatality rate (1.6%) than the medically treated cases (7.7%). However, the surgical cases had a better prognosis at the time of infarction than the medical cases. When the severity of infarction (PCR score) and year of admission were considered, coronary surgery in the post-infarction year had no independent effect on outcome.

Prognosis after recovery from first acute myocardial infarction: determinants of reinfarction and sudden death

Factors associated with total cardiac mortality, sudden cardiac death and reinfarction were studied in 325 male survivors aged younger than 60 years of age (mean 50) of a first myocardial infarction (MI). All patients had undergone exercise testing and cineangiocardiography 4 weeks after MI, 24% underwent coronary artery surgery and 30% received beta-blocking therapy. Patients were followed 1 to 6 years (mean 3.5). Total cardiac mortality was best predicted by the left ventricular (LV) ejection fraction (EF) and by a coronary prognostic index. In contrast, neither the severity of coronary arterial lesions measured with a scoring system nor the results of the exercise test gave significant prediction of mortality. Of the 2 major late sequelae of MI, reinfarction could not be predicted by any clinical or cineangiocardiographic variable. However, sudden death not associated with reinfarction was significantly more common (p less than 0.001) when EF was less than or equal to 40% than when it was greater than 40%. Comparison of patients with an EF less than or equal to 40% who did or did not die suddenly showed that LV dilation (high volumes at ventriculography) was an added risk factor, but the extent of coronary occlusions and stenoses was not. It is concluded that, at least for groups of patients treated with standard modern methods after MI, the main determinant of medium-term survival is the extent of LV damage. The state of the coronary arteries and the presence of ischemic myocardium during exercise are only of secondary importance for survival.

Rehabilitation of the MI survivor. Management options to maximize posthospital outcome

Rehabilitation of the survivor of myocardial infarction (MI) involves efforts to restore or retain maximal function physiologically, psychologically, vocationally, and socially. Goals include delaying or preventing complications, preventing or reversing deconditioning, improving the patient's ability to participate in chosen activities and facilitating his or her return to work, improving psychologic adjustment, and reducing risk factors. A comprehensive rehabilitation program can be guided by an understanding of the natural history of MI in survivors and the risks versus benefits of the interventions discussed.

Uncomplicated acute myocardial infarction: long-term management

The components of long-term management of the patient recovered from uncomplicated myocardial infarction include identification and alteration of nonatherosclerotic factors that might increase the risk of early reinfarction or sudden coronary death, alteration of modifiable coronary atherosclerotic risk factors to prevent progression or induce regression of the atherosclerotic process, and optimal restoration and maintenance of residual cardiovascular function to help improve the quality of life of the patient.

Prognosis and treatment of asymptomatic coronary artery disease

Despite the large number of studies dealing with the natural history of angiographically defined coronary artery disease, there is still a paucity of data on the prognosis of totally asymptomatic persons. From the small number of reported studies, it appears that prognosis in selected asymptomatic patients may be better than that of symptomatic patients. However, the annual mortality rate in the subgroup of asymptomatic patients with triple vessel disease was as high as 4 to 5% in some studies that included patients with prior myocardial infarction or mild symptoms, or both. This has reinforced the views of those who advocate a more aggressive medical/surgical approach to asymptomatic patients with left main and triple vessel disease, especially if they have had a prior infarction. Although several small series of surgically treated patients have been reported to have excellent short-term survival rates, the absence of adequate control groups in nearly all of these studies has left the issue of prophylactic revascularization unresolved. Until there is more knowledge of prognosis in patients not operated on, it is likely to remain unresolved.

The high risk patient after recovery from myocardial infarction: recognition and management

Patients at high risk for recurrent myocardial infarction or death can be identified after recovery from an acute myocardial infarction. Predictors of high risk at the time of initial hospital discharge may vary in different localities depending on the underlying baseline characteristics of the patient cohort. The medical records were analyzed of 139 patients discharged from San Francisco General Hospital after recovery from an acute myocardial infarction between July 1978 and September 1981. Multivariate stepwise discriminant analysis of 20 variables contributing to sudden and total death identified complex ventricular ectopic rhythm as the most important variable, followed by age. Failure to receive chronic long-acting nitrates was an independent variable contributing to total mortality but not to sudden death, while the presence of an initial anterior myocardial infarction and impaired left ventricular function were independent variables contributing to sudden death but not to total mortality. Routine 24 hour ambulatory monitoring, radionuclide ventriculography and submaximal stress tests performed during the second week after recovery from an acute myocardial infarction provide identification of a high risk cohort for subsequent recurrent myocardial infarction or death and permit appropriate interventions designed to lessen risk to be undertaken.