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Exercise testing is generally accepted for prognostic assessment of patients after infarction, but the prognostic value of transient myocardial ischemia during ambulatory electrocardiographic monitoring remains controversial. Of 281 consecutive postinfarction patients, 173 patients (132 men, 41 women) were prospectively studied with 24-hour Holter monitoring 14 [+ or -] 5 days after acute myocardial infarction, and with submaximal exercise testing after 15 [+ or -] 7 days. Patients with either conduction disturbances or pacemaker rhythm and 71 patients with digitalis medication were excluded. Myocardial ischemia was defined as horizontal or descending ST depressions or transient ST elevations [is greater than or equal to] 0.1 mV with or without angina pectoris. The follow-up period was 1 year. Myocardial ischemia was observed in 40 patients (23%) during Holter monitoring, and 96% of the episodes were asymptomatic. Ischemia occurred during exercise testing in 46 patients (27%), two thirds of whom had no symptoms. Ischemia was detected by both methods (group A) in 19 patients (11%), with exercise testing only (group B) in 27 patients (16%), and with Holter monitoring only (group C) in 21 patients (12%). In 106 patients (61%), ischemia could not be ascertained at all. The 4 groups were comparable with regard to sex and age distribution, coronary risk factors, and medication. During follow-up, 50 patients (29%) experienced clinical cardiac events: 6 patients died, 7 had recurrent myocardial infarction, 14 developed unstable angina pectoris and required immediate revascularization, and 23 patients had recurrent but stable angina. The frequencies of those with cardiac events were 63, 26, 14 and 26% in groups A, B, C and D, respectively -- significantly higher in group A than in the other groups (p

The aim of this study was to analyze the long-term clinical outcome of 60 prospectively studied patients with documented sustained ventricular tachyarrhythmia that was not inducible during baseline programmed ventricular stimulation: 39 with cardiac arrest due to noninfarction ventricular fibrillation (VF) and 21 with mild hemodynamically compromising sustained ventricular tachycardia (VT). Left ventricular ejection fraction was 55 [+ or -] 14% in the VF group and 50 [+ or -] 13% in the VT group (difference not significant). Patients were discharged without conventional antiarrhythmic drugs and received only empirical [beta]-blocker therapy. During a mean follow-up period of 21 [+ or -] 16 months (mean [+ or -] SD), 10 of 60 patients (17%) died suddenly. The actuarial incidence of sudden death at 1 and 4 years was similar in both groups (VF group, 10 and 20%; VT group, 16 and 16%) (p = 0.48). The actuarial incidence of sudden cardiac death was significantly higher in patients with left ventricular ejection fraction [is less than or equal to] 40% than in those with >40% (1-year incidence in VF group, 40 vs 0%; VT group, 50 vs 0%) (p = 0.005 and p = 0.01, respectively). Multivariate regression analysis identified left ventricular ejection fraction [is less than or equal to] 40% and previous myocardial infarction as the only independent predictor of sudden cardiac death. The occurrence of frequent ventricular pairs during Holter monitoring was the only independent predictor of sustained VT recurrences. It is concluded that patients with sustained ventricular tachyarrhythmia in whom arrhythmia was noninducible during baseline ventricular stimulation and not treated with antiarrhythmic therapy have a favorable outcome if left ventricular ejection fraction is high. However, reduced left ventricular ejection fraction identifies a subgroup at high risk of sudden cardiac death. Patients with mild hemodynamically compromising sustained VT have a similar risk of dying suddenly as those resuscitated earlier from cardiac arrest.

To evaluate the impact of late reperfusion of an infarct-related coronary artery on left ventricular (LV) function in the month after myocardial infarction, findings from 368 patients in the intravenous Streptokinase in Myocardial infarction study are presented. All patients had a late peaking in the creatine kinase-MB serum time-activity curve, suggesting absence of early reperfusion. Contrast angiography was performed 1 month after the acute event. The infarct-related coronary artery was patent in 74 of 116 (64%) streptokinase-treated patients and 141 of 252 (56%) patients treated with anticoagulant therapy (placebo group). In all baseline variables, including the actually developed enzymatic and electrocardiographic infarct sizes, there were no differences between the patent-or occluded-artery groups. A patent infarct artery 1 month after infarction was associated with significantly better LV function regardless of the vessel involved and whether or not patients had been treated with streptokinese. Ejection fraction in patients with patent versus artery was 56 [plus or minus] 13 versus 50 [plus or minus] 14 (p [less than] 0.0005). Most benefit was noted in patients in whom the proximal left anterior descending coronary artery was affected: ejection fraction was 52 [plus or minus] 14 versus 36 [plus or minus] 12% (p [less than] 0.0005). Our data confirm that restoration of adequate flow through an infarct-related coronary artery beyond the time window for actual salvage of ischemic myocardium has a definite beneficial effect on LV function. Am J Cardiol 1989;64:878-884), Coronary arteries may become obstructed and lead to myocardial ischemia, an insufficient supply of blood to the heart. If untreated, ischemia may progress to heart attack (myocardial infarction). The effect of delayed reperfusion, restoration of blood flow, on the function of the left ventricle after a heart attack was assessed. The cases of 368 patients participating in the Intravenous Streptokinase in Myocardial Infarction study were reviewed. Generally, the blood levels of the enzyme creatine kinase-MB peak within 15 hours after a heart attack, indicating early reperfusion in the previously obstructed artery. All patients were shown to have a delay in the peak of creatine kinase-MB levels, suggesting the absence of early reperfusion. The blood vessels were X-rayed one month after the infarction. Results showed that the previously obstructed coronary artery was open (patent) in 74 of 116 patients treated with streptokinase, an agent that breaks down blood clots, and in 141 of 252 patients receiving anticoagulants, drugs that prevent blood clotting. A previously obstructed coronary artery that becomes patent one month after the heart attack is associated with better left ventricular function and improved ejection fraction (the amount of blood pumped by the left ventricle with each heartbeat). The most beneficial effects on ejection fraction occurred in patients with recovery of flow in the proximal left anterior descending coronary artery. The results show that the late restoration of blood flow in a previously obstructed coronary artery has beneficial effects on the function of the left ventricle after myocardial infarction. (Consumer Summary produced by Reliance Medical Information, Inc.)