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In 309 postmyocardial infarction patients (age 40 +/- 7.7 years) without persistent ischemia there is only a weak correlation between ejection fraction (EF) and exercise tolerance (r = 0.45, p < 0.01), and between EF and maximum cardiac output (CO; r = 0.41, p < 0.01) and maximum pulmonary capillary wedge pressure (PCWP; r = -0.32, p < 0.001). The same was true for exercise tolerance and maximum PCWP (r = -0.53, p < 0.001). A big scattering of individual values could be observed. Although we found a high positive correlation between maximum CO and exercise tolerance (r = 0.80, p < 0.001), in individual cases a low CO could be related to high exercise tolerance and vice versa. In the multivariate analysis, only the heart volume/kg body weight and maximum PCWP could be shown to be of independent prognostic importance for survival and/or mortality in the following years (chi 2 = 5.9, p < 0.015 and chi 2 = 7.2, p < 0.007, respectively).

Residual high-grade coronary stenosis and collateral flow are frequent findings in the chronic phase after a Q-wave acute myocardial infarction (AMI). The prognostic importance of a residual stenosis of the infarct artery and of collateral flow to the infarct area was analyzed in a group of 102 young patients (mean age 35 years, range 22 to 39) who had survived an anterior wall Q-wave AMI. Patients whose only significant lesion (greater than 50% luminal diameter reduction) was in the proximal portion of the left anterior descending artery were enrolled in the study. A 50 to 74% diameter stenosis was present in 33 of 102 patients (32%), 43 (42%) had a 75 to 99% stenosis and 26% had a total occlusion of the infarct vessel. Collateral vessels, which were evaluated by a scoring system, were present in 52 of 102 patients (51%). Four percent had only faint (score 1), 17 of 102 patients (17%) had moderate and 32 patients (31%) had good collateral flow (score greater than 4). The 8-year cumulative mortality was 15.2%--an eightfold increase compared with the age-matched general population. No patient with less than 75% stenosis died during follow-up, whereas the cumulative 8-year mortality was 23 and 17% in patients with a 75 to 99% stenosis or total occlusion, respectively (p less than 0.01). Patients with at least moderate collateral flow had a mortality rate of 21%, versus 8% for patients without or with faint collateral flow (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

In a follow-up study (mean = 3.6 years) of 555 men under 40 years of age (mean = 35.7 years) who had recently suffered transmural myocardial infarction, 44 patients (7.9%) suffered cardiac death with an annual rate of 2.2%. In a bivariate analysis a significant correlation was found between cardiac death and work capacity (p less than 0.02), vessel involvement (greater than 50% stenosis), left ventricular impairment as evaluated by ventriculography (p less than 0.001) and heart volume enlargement (p less than 0.01). There was no significant correlation between the degree of ST-segment depression and ventricular premature depolarisation (during exercise test). Complex results from non-invasive approaches can identify groups with good and bad prognosis as effectively as invasive techniques.

This review discusses the stepwise approach to postinfarction patients. For some patients only a few basic steps are needed, for others the whole diagnostic spectrum becomes necessary. The baseline diagnostic workup at the time of discharge from the hospital includes: history, clinical examination and risk factor analysis, ECG at rest; x-ray examination of the heart; Holter-ECG recording and exercise testing. The results of this routine diagnostic program determine whether additional and invasive methods are necessary, e.g. echocardiography, myocardial perfusion scintigraphy, radionuclide angiography and coronary angiography. The indication for coronary angiography should be adjusted to the indications for aortocoronary bypass surgery and aneurysmectomy. In young postinfarction patients and those in specific jobs, coronary angiography is also indicated to improve the evaluation of prognosis.

In patients with myocardial infarction (MI) the presence or absence of lesions in vessels other than the one which perfuses the infarcted area, has implications regarding coronary bypass surgery, long term anticoagulant therapy, work capacity and prognosis. We investigated whether involvement of a 2nd or 3rd vessels as demonstrated by coronary angiography can be predicted on the basis of angina pectoris and/or ischemic ST-segment depression during exercise. Inferior myocardial infarction (IMI, n = 146) Severe lesions (greater than or equal to 75%) of a 2nd or 3rd vessel were found in 61.7% of patients with IMI, who developed angina pectoris and ischemic ST-segment depression, in 18.6% of patients with ST-segment depression only, in 9.1% of patients with angina pectoris only and in 3.4% with neither angina pectoris nor ST-segment depression. Anteroseptal infarction (ASI, n = 116) Severe lesions (greater than or equal to 75%) of a 2nd or 3rd vessel were found in 30.2% of patients with ASI, who developed Angina pectoris and ischemic ST-segment depression; in 26.6% of patients with ST-segment depression only, in 20.0% of patients with angina pectoris only and in 3.0% of the patients with neither angina pectoris nor ST-segment depression. The clinical implications of the results are discussed.

500 patients under the age of 40 with a history of myocardial infarction underwent a first coronary angiography. 193 patients who had had a first angiogram more than 3 years before were asked to undergo a repeat study irrespective of symptoms during that time interval. 34 patients did not respond, 27 refused, 13 had died, and 5 were excluded for medical reasons. 114 underwent a repeat study on average 3.8 years after the first angiogram. Progression or regression of coronary artery disease was assumed where a difference of 2 grades based on the AHA-classification of stenosis was found. The majority of patients exhibited no change in coronary morphology. Progression was equally frequent in all three vessels. Regression was almost exclusively seen in patients with unilocular disease, occurred predominantly in the LAD and was more frequently seen in patients below 35 years than in the 35-39 age group. Patients with progression of stenosis included a significantly larger number who continued to smoke during the observation period.

With 218 postinfarction patients under 40 years of age who all underwent coronary angiography, the question in priority is: Can myocardial infarction in young age be characterized by special constellation of risk factors and by specific coronary morphology? Compared with results from literature the risk factors hypertension and diabetes seem to be of less importance than in older patients, smoking on the other hand seems to be more significant: 90.5% of postinfarction patients under 40 years of age were smoking regularly. Coronary angiography proved a pre-domination of 1-vessel disease: 72% showed 1-vessel, 17.9% 2-vessel and 10.1% 3-vessel disease. These findings and those from literature show that the majority of patients with myocardial infarction in young age have the following characteristics: In connection with the risk factor smoking the sclerotic coronary vessel process is developing rapidly, very often at a single spot. Since no longterm gradual occlusion process occurs, no prolonged period of angina pectoris precedes the infarction. There is no time for the development of an adequate collateral circulation; it follows that the infarction is a large one. After the acute infarction there is no angina pectoris.

In 10% (n = 139) of 1,383 patients in the chronic phase of myocardial infarction left ventricular mural thrombi on a-/dyskinetic segments were present in the 2D-echocardiogram. Thrombi were more often seen in patients with anterior wall infarct (14% of 734) or combined anterior-posterior infarcts (11% of 337) than in those with posterior wall infarct (0.6% of 312). Thrombi were most frequent in patients with left ventricular aneurysm (26% of 362). Generally, our patients with left ventricular thrombi had suffered large infarctions, involving on average 42% of the wall segments. Accordingly, signs of severe left ventricular damage were found in most of these patients: in 69% global ventricular dilation was present in the echocardiogram, in 64% the global heart size, determined by chest-ray was enlarged, in 42% the exercise tolerance on the bicycle ergometer was limited to 25 watts or less, 29% had congestive heart failure, and 17% severe ventricular arrhythmias. Systemic embolization had occurred in 7.9% of the 132 thrombus patients, but in only 0.7% of the 1,244 patients without thrombi. At the time of the thrombus diagnosis by means of 2D-echocardiography, 90% of the thrombus patients had not received effective anticoagulant therapy. Follow-up was possible in 65 of these patients and showed thrombus regression in 45 patients, 93% of whom were effectively anticoagulated. Of the 20 patients with persisting thrombi only 20% were under an effective anticoagulant drug management. If anticoagulant therapy has to be stopped, a former thrombus patient runs a high risk of developing thrombi also in the chronic phase of myocardial infarction.

Nowadays, the majority of patients undergoing aortocoronary bypass surgery have a history of myocardial infarction. In our first series of 1000 patients operated between 1973 and 1979, about two thirds of the patients had suffered myocardial infarction; about 80% of them within the previous three months. The method most frequently used to select post-infarction patients for coronary angiography is a simple exercise test. The post-infarction period in the context of this symposium was defined as the first 12 weeks after infarction. As far as exercise tests are concerned, we may divide this period into three subperiods: the very early post-infarction period, especially the first week after infarction. Exercise testing does not play a role in this very early period; the second period is the time of an early post-infarction exercise test or the predischarge exercise test (second and third week); from the fourth to the twelfth week in many European countries, rehabilitation measures will follow, usually in a special institution. This is the time of what we will call in short 'the late post-infarction exercise test'.

Coronary morphology, risk factors, long-term prognosis, and progression of coronary arteriosclerosis were investigated in 679 (649 mean and 30 women) post-infarction patients under 40 years of age. These patients represented 80% of 844 MI patients under 40 who were referred to our hospital in the years 1973-1980; 20% had refused coronary angiography; 465 patients were followed up for 1-7 years (mean 3.5 years). In 164 patients, a second coronary angiography was performed 3.8 years after the first angiogram, which was done an average 3 months after the acute episode. The main results were as follows: 8.4% of the patients had zero-vessel disease and 3.7% had a normal coronary angiogram. The majority had single-vessel disease (57.3%). The prevalence of zero-vessel disease decreased with age while that of multivessel disease increased. With increasing vessel involvement, the prevalence of hypercholesterolemia, hypertriglyceridemia, and hypertension increased. A history of smoking was equally common in patients with zero-, single-, double-, and triple-vessel disease. In women the combination of smoking and the use of oral contraceptive drugs was frequently seen. In one-quarter of the zero-vessel disease patients, the infarction occurred during unusually intense physical exercise. The statistical analysis of the survival data using the proportional hazards model (univariate analysis) showed the variables heart volume/body wt., ventricular arrhythmias, PCP at rest, PCP max, work capacity, ventricular function, and number of diseased vessels to be of prognostic importance. Multivariate analysis using this model revealed the following independent variables to be relevant to prognosis: heart volume/body wt., ventricular arrhythmias, ventricular function, and number of diseased vessels. After an average of 3.8 years since the first coronary angiography, 28.6% of the patients showed a significant progression of coronary arteriosclerosis (at least two degrees of stenosis according to the AHA classification). In the subgroup of patients with multilocular disease in the first angiogram, progression was 10 times as frequent as in a group with initial unilocular disease (34.3% vs 3.6%). Patients with progression had continued to smoke significantly more often than patients without progression (38.4%) vs 14.5%). Regression of coronary angiographic findings was significantly more frequent in the group of patients with initial unilocular disease than in those with multilocular disease in the first angiogram (28.6% vs 10.6%). Regression might be explained as recanalization and organization of a thrombus.(ABSTRACT TRUNCATED AT 400 WORDS)

Exercise tests were performed in 521 post-infarction patients to consider the acute effect of 5 mg pindolol orally. The main results are: In patients with an initial heart rate(HR) of more than 68 beats/min the HR at rest was reduced. This reduction was more pronounced the higher the initial HR. With HR below 68 beats/min there was a slight increase due to the intrinsic sympathomimetic activity of pindolol. In exercise testing the decrease in HR also correlated positively with the initial values. During the first test run (i. e. without pindolol) angina pectoris was observed in 88 patients. 70% of these patients showed an improvement or total disappearance of angina when pretreated with pindolol. Without medication, 66 patients showed ventricular extrasystoles which diminished or disappeared in 40 after pindolol.

308 patients with the clinical diagnosis of intramural myocardial infarction made elsewhere were re-investigated more than eight weeks after the acute event. ECGs and pulmonary "wedge" pressures were recorded at rest and during exercise and coronary angiography performed (Sones' or Judkin's technique). In the first group (1973/74) of 77 patients, 35 (45.5%) had a normal coronary angiogram, compared with 0.7% in a control group with transmural myocardial infarction. A normal coronary angiogram was found in 85% of the 40 patients who had no angina during exercise. In a second group (1974/77) of 231 patients, there was a steady decrease in the number of patients without angina pectoris during exercise, in parallel with a decrease in the number of those with normal coronary angiograms. This change in pattern was apparently due to improved diagnosis in the referring hospitals. Of the 37 patients (first group) with angina during exercise, all but one were subsequently found to have significant coronary arteriosclerosis. It is suggested that most patients with a normal coronary angiogram had sustained a myocarditis and (or) pericarditis which produced the symptoms and the altered ECGs, leading to the misinterpretation of "intramural myocardial infarction".

We examined the long-term prognosis in 213 survivors of the acute phase of a transmural anterior myocardial infarction with single vessel disease. All patients (pts) had undergone coronary angiography ad exercise testing at a mean interval of 6 months after myocardial infarction. 117 pts had a single lesion in the proximal LAD; 96 pts had a lesion after the first septal branch. The mean follow-up time was 4.5 years. The annual mortality for the whole group was 1.3%; 77% of all deaths occurred in pts with a greater than or equal to 75% proximal LAD lesion. The annual mortality of this subgroup was 2.75%--significantly higher than the 0.5% annual mortality in the remainder (p less than 0.003). Exercise-induced angina was of prognostic importance only in pts with greater than or equal to 75% proximal LAD lesions (annual mortality 7.25% in this small subgroup). None of the patients with angina and a lesion after the first septal branch died during follow-up. The degree and the location of the stenosis are of prognostic importance even after transmural myocardial infarction. Exercise-induced angina In pts with 1-VD after transmural anterior myocardial infarction is associated with a poor prognosis if it occurs in those with a greater than or equal to 75% stenosis in the proximal LAD. These results may help in the decision-making process for transluminal angioplasty or bypass surgery.