The role of beta receptor blockade in preventing sudden death

Abstract

The high mortality rate from coronary heart disease in hypertensives can only be substantially reduced if sudden coronary death rates can be decreased. The aim of this review is to discuss how treatment may be tailored to reduce the risk of sudden death in high-risk patients. Clinical trials have not yet produced long-term primary prevention data on the effects of angiotensin converting enzyme (ACE) inhibitors, calcium antagonists or alpha-blockers on cardiovascular complications and sudden death in hypertensive patients. Further, the conclusion from large-scale secondary preventive studies presently available on ACE inhibitors and calcium antagonists is that their impact on sudden death has been disappointing. By contrast, some beta-blockers have reduced sudden death and other coronary events both in primary and secondary preventive studies. The benefits have been attributed to beta 1-blockade, and seem to be independent of blood pressure control. It cannot be assumed that all beta-blockers are equally effective in preventing ventricular fibrillation, sudden death and other coronary events. To date, the best documented data cover the lipophilic beta-blockers and it is speculated that by increasing levels of cardiac vagal tone and electrical stability in the heart, beta 1-blockade in the brain might contribute to the reduction in sudden death risk seen with these beta-blockers.