ISCHEMIC-HEART-DISEASE - HOW WELL ARE THE RISK PROFILES MODULATED BY CURRENT BETA-BLOCKERS

In acute myocardial infarction, intravenous beta blocker therapy has b een tested in about 30 controlled, randomized trials. Of these, the IS IS-1 using atenolol and the MIAMI trial using metoprolol are the most important. In a total of 26,437 patients, total deaths were reduced by 62 during day 1 and by 64 during the first week, i.e. 97% of the live s were saved during the first day of beta blocker treatment. In post-m yocardial infarction, oral beta blocker maintenance treatment has been used in about 35,000 survivors in placebo-controlled trials. Of these , the timolol, metoprolol and propranolol (BHAT) trials are the most i mportant. In the timolol trial lasting for 33 months, total death, tot al cardiac death and re-infarction rate were significantly reduced. In the metoprolol study lasting for 3 months, total and cardiac mortalit y were reduced, and in the BHAT study lasting for 25 months fatal and non-fatal re-infarction combined was significantly reduced. Primary pr evention of coronary heart disease has been the intention in hypertens ion trials. Despite the fact that beta blockers are potent agents agai nst elevated blood pressure, a well-established coronary risk factor, no controlled trial with a placebo or untreated control group has show n a definite preventive effect on coronary heart disease. The reason f or this apparent paradox is not known, but many speculations have been aired that the lack of effect might be due to adverse metabolic effec ts of most beta blockers.