Medical and surgical management of early Q wave myocardial infarction. II. Effects on mortality and global and regional left ventricular function at 10 or more years of follow-up.

To determine the long-term effect of surgical reperfusion on survival and left ventricular function of patients with anterior and inferior Q wave myocardial infarction, 387 patients were followed up for greater than or equal to 10 years after early Q wave infarction. In the anterior infarction group, 102 received conventional therapy and 101 underwent surgical reperfusion. The overall hospital mortality rate in the medically and surgically treated patients was different (16.7% [17 of 102] versus 6.9% [7 of 101], p less than 0.05). The cumulative 13 year actuarial mortality rate widened between the anterior medical and surgical groups (54% versus 31%, p = 0.0003) by the adjusted Cox proportional hazards model. The hospital mortality rate with early reperfusion (that is, less than or equal to 6 h of symptom onset) was 2% (1 of 51), whereas the mortality rate with late reperfusion was 12% (6 of 50). The 13 year actuarial cumulative mortality rate was significantly lower in both the early and late reperfusion groups (30% and 33%, respectively) than in the conventional therapy group (54%, p = 0.0006). The mortality rate in patients receiving surgery after surviving initial medical therapy was 50% (15 of 30). In the survivors of anterior Q wave myocardial infarction, improved global ejection fraction was seen in the patients undergoing early (54 +/- 13%) and late (50 +/- 10%) surgery relative to those receiving conventional therapy (43 +/- 11%, p less than 0.05). Only the early reperfusion group had better regional function of the anterior wall than that of the conventional therapy group. Thus, ventricular function correlated with improved long-term survival. In the patients with inferior Q wave myocardial infarction, the overall hospital mortality rate in the medical and surgical groups was not different (6.1% [6 of 98] versus 4.6% [6 of 86], p = NS). Likewise, the 13 year actuarial cumulative mortality rate was not different between the medical and surgical groups overall (32% versus 30%, p = 0.29) by the adjusted Cox proportional hazards model. The hospital mortality rate in the early reperfusion group was lower than that in the late reperfusion group (2.0% [1 of 49] versus 8.1% [3 of 37], p = NS). The 13 year actuarial cumulative mortality rate was lower in the early surgical group compared with that in the medical group (19% versus 32%, p = 0.04). The late surgical group had a similar 13 year actuarial cumulative mortality rate to that of the medical group (47% versus 32%, respectively, p = 0.47).(ABSTRACT TRUNCATED AT 400 WORDS)

Coronary arteriographic findings in acute transmural myocardial infarction.

To describe the coronary arteriographic findings during early transmural myocardial infarction and to define the prevalence of coronary thrombosis by arteriography, we performed coronary arteriography and left ventriculography within 24 hours from symptom onset of transmural myocardial infarction in 517 patients. The coronary arteriographic findings included total and nontotal coronary occlusion with and without coronary thrombosis. Coronary spasm or severe stenosis in the affected vessel were discovered in a minority of patients. The coronary arteriographic characteristics of thrombus included persistent staining of intraluminal material by the contrast material, local retention of the contrast agent in the involved coronary artery, and intracoronary filling defect occurring mostly in nontotal occlusion. Of the 517 patients, 368 were studied within 6 hours of symptom onset, 85 within 6-12 hours and 64 within 12-24 hours. There was a systematic difference between total coronary occlusion and coronary thrombosis in each group. This was determined by arteriographic findings (judged positive or negative) relative to surgical findings. Both total coronary occlusion and coronary thrombosis were more prevalent in the early treatment (within 6 hours from symptom onset) group. Total occlusion and thrombosis declined significantly in the 6-12- and 12-24-hour groups. These data suggest that thrombus is encountered by arteriography and confirmed by surgical exploration within the first 6 hours from symptom onset of transmural infarction in approximately 80% of patients. Coronary thrombosis by coronary arteriography decreases in parallel with total coronary occlusion during the first 24 hours after acute transmural infarction, suggesting that coronary spasm or thrombus formation with subsequent recanalization are important in the evolution of transmural infarction. Despite many factors involved in the pathogenesis of transmural myocardial infarction, coronary thrombosis appears to be the final common pathway converting chronic coronary disease to acute myocardial infarction in the majority of patients.

Anterior transmural myocardial infarction: effects of surgical coronary reperfusion on global and regional left ventricular function.

Global and regional left ventricular function were assessed before and after surgical coronary reperfusion in 54 patients surviving anterior transmural myocardial infarction. Two groups were identified. Group I (n = 34) was treated within 4.8 +/- 0.7 (mean +/- standard deviation) hours of onset of symptoms of anterior transmural myocardial infarction, and Group II (n = 20) was treated 9.2 +/- 4.8 hours from the onset of symptoms (p less than 0.01). On study entry, the two groups were similar in all characteristics except global left ventricular ejection fraction (48 +/- 9 versus 42 +/- 13%, p less than 0.05). Regional ejection fraction was obtained by computer-assisted planimetry from ventriculographic tracings at end-systole and end-diastole. The anterior wall was divided into four equal segments from the apex (area 1) to base (area 4). Areas 2 and 3 defined the midportion of the anterior wall of the left ventricle. This yielded four fractional changes expressed as ejection fraction in percent. Global and regional ejection fractions (from apex to base) of the anterior wall significantly improved in Group I (from 48 +/- 9 to 55 +/- 11%; 7 +/- 17 to 18 +/- 20%; 12 +/- 14 to 25 +/- 18%; 25 +/- 15 to 38 +/- 17%; and 39 +/- 13 to 41 +/- 12%) (p less than 0.05, except for the basal area), but only to a minor degree in Group II (from 42 +/- 13 to 45 +/- 16%; 9 +/- 10 to 13 +/- 15%; 10 +/- 10 to 17 +/- 10%; 27 +/- 16 to 32 +/- 14%; and 37 +/- 10 to 36 +/- 13%) (all p values were not significant [NS] except for region 2). These data suggest significant enhancement of global function and regional wall motion in selected patients if surgical reperfusion is performed within 6 hours from the onset of symptoms of anterior infarction. Little improvement can be expected when the procedure is instituted later than 6 hours from peak symptoms, although improvement in some patients occurs if adequate collateral perfusion or nontotal left anterior descending coronary occlusion is present. In spite of functional improvements, some contractile deficit persisted throughout the period studied even when successful reperfusion was achieved early during evolving anterior transmural myocardial infarction.

Intraaortic balloon counterpulsation with and without reperfusion for myocardial infarction shock.

Forty patients were treated for cardiogenic shock secondary to acute myocardial infarction. Twenty-one (group 1) were treated with intraaortic balloon counterpulsation and 19 (group 2) were treated with counterpulsation and coronary artery bypass grafting. The groups were similar in age, incidence of previous infarction, initial hemodynamics and coronary anatomy. The in-hospital mortality between group 1 (52.4%) and group 2 (42.1%) was not significantly different. The difference in long-term mortality between group 1 and group 2 was substantially different (71.4% vs 47.3%). The subset of group 2 (n = 12) that underwent reperfusion and counterpulsation within 16 hours from the onset of symptoms of infarction had a lower mortality (25.0%) than the subset (n = 7) that underwent operation more than 18 hours after the onset of symptoms (71.4%). The long-term mortality in the subset of group 2 patients operated on within 16 hours after the onset of infarction was significantly different from that in group 1 (25.0% vs 71.4%, p less than 0.03). The data suggest that reperfusion with counterpulsation is more effective when carried out early. Patients who develop shock more than 18 hours after the onset of symptoms of infarction appear to benefit most if treated with counterpulsation alone.