Limitation of myocardial infarct size in patients less than 66 years treated with alprenolol.

Abstract

Patients [282] less than 66 yr of age admitted with suspected or definite myocardial infarction were allocated in a random fashion to treatment with alprenolol or placebo. Treatment was started immediately upon admission with 5-10 mg alprenolol or placebo i.v., followed by 200 mg alprenolol or placebo orally twice a day for 1 yr. In 178 patients a definite myocardial infarction was diagnosed. Mycardial infarct size could be estimated from serial determinations of serum total creatine kinase [CK] in 42 patients treated with alprenolol and 43 patients receiving placebo. Median infarct size was 20.6 CK g eq/m2 body surface in the alprenolol group, the corresponding figure in the placebo group being 34.4 CK g eq/m2 body surface. Median rate of release of creatine kinase from the ischemic myocardium was 27.7 U/l per h and 48.0 U/l per h after alprenolol and placebo, respectively. Alprenolol limited infarct size significantly provided the treatment was started within 12 h of the onset of symptoms.