[Combined use of nitrates and beta-adrenergic blockaders in patients with acute myocardial infarct]

A combination of isosorbide dinitrate (40-120 mg daily) and propranolol (80-160 mg) was administered to 146 patients during the early hours of myocardial infarction. The therapeutic effect was assessed for 10 days and compared to the effect observed in a control group of 70 patients selected at random. The combination used was shown to relieve the pain syndrome and extrasystolic arrhythmia during the early days of the disease. The occurrence of signs of heart failure was twice as low during the observation period, as compared to the control group. The treatment evoked typical hemodynamic changes: rhythm deceleration (by an average 7%), a fall in systemic arterial blood pressure (by 19%) and in "double product" (by 25%), a moderate reduction of cardiac output (by 15%) coupled with a marked drop in left-ventricular filling pressure (by 25%). The spread of infarcted area in the first days after the attack, as evidenced by serial electrocardiotopograms and the activity of serum CPK and its MB fraction, was recorded in 13.9% of the treated patients and in 44% of the controls (p less than 0.001).