Does long-term beta blockade prevent transmural myocardial infarction in patients with established coronary heart disease admitted with prolonged ischaemic myocardial pain?
Long-term beta-blockade in patients with coronary heart disease may protect against the development of transmural myocardial infarction when presenting with prolonged ischemic pain, without increasing adverse hemodynamic events.
The clinical behaviour of 90 patients on beta-blocking drugs for established coronary heart disease who were admitted to a coronary care unit with prolonged ischaemic myocardial pain was compared with that of 90 similar patients not on this therapy. Transmural myocardial infarction was confirmed in 30 of the patients on beta-blockers and in 62 controls. A diagnosis of myocardial necrosis without infarction was made in 20 patients on beta-blockers and in 14 controls. Coronary insufficiency was diagnosed in 40 patients on beta-blockers and in 14 controls. The incidence of simus bradycardia, hypotension, syncope, and radiological pulmonary oedema was similar in the two groups. Established beta-blockade, therefore, has not been shown to prejudice the outcome of patients with coronary heart disease admitted to hospital with prolonged ischaemic myocardial pain. On the contrary, it may protect some patients from the development of a myocardial infarction.
Fox et al. (Sat,) studied this question.