Early postinfarction angina: therapeutic strategies

In patients with recurrent chest pain in the immediate postinfarction state, one must determine whether the recurrent chest discomfort is related to myocardial ischemia or not. If recurrent ischemia is present then it may be due to either (1) transient increase of myocardial oxygen demand over a fixed coronary reserve, (2) transient decrease of myocardial oxygen supply, or (3) a combination of both. Coronary angiography reveals that most patients have double or triple vessel disease. The presence of postinfarction angina portends a poor prognosis. Reinfarction rate has been reported as high as 28% during initial hospitalization and mortality has been as high as 57% at six months follow-up. Intravenous nitroglycerin seems to be an important foundation therapy for the management of postinfarction angina. The use of beta blockers has reduced mortality by 24% compared to placebo in this patient subgroup. Calcium antagonists have proven efficacious in patients with non-Q-wave myocardial infarction and postinfarction angina. Thrombolytic therapy, chronic anticoagulation and antiplatelet therapy are not proven efficacious at this time. Coronary angioplasty is usually successful initially but is associated with an early myocardial infarction rate varying from 1.4 to 13%. Mortality rate is usually low as is late myocardial infarction rate. Recurrent angina occurs commonly in these patients. Surgical therapy in the early infarction state should be offered to those patients who have a poor response to maximal medical therapy whose coronary artery obstructions are not amenable to PTCA. At the time of coronary angiography if partially occlusive thrombus is identified, intravenous heparin and aspirin should be given to prevent more thrombus formation and total occlusion.