Thrombolytic therapy: adjuvant mechanical intervention for acute myocardial infarction.

Following successful pharmacologic thrombolysis, early coronary angiography frequently shows a tight residual stenosis in the infarct-related artery at the site of recent occlusion. Approaches to the management of the residual stenosis have undergone a gradual evolution from an aggressive strategy of immediate balloon dilation to a more conservative approach. Randomized, controlled trials have indicated that immediate percutaneous transluminal coronary angioplasty (PTCA) is associated with no greater recovery in regional or global left ventricular function, and a tendency toward an increased incidence of complications, including the need for emergency coronary artery surgery and blood transfusion. The role of immediate rescue PTCA for failed thrombolysis has not been as rigorously investigated, but selected patients, including those with evidence of ongoing myocardial ischemia or hemodynamic instability, may benefit from this approach. A major source of current controversy is the value of routine coronary angiography after uncomplicated myocardial infarction. Two carefully conducted trials have indicated that a conservative strategy of clinically indicated, predischarge cardiac catheterization may be associated with an increased need for readmission and late, elective cardiac catheterization when compared with a more invasive strategy of routine coronary angiography, but that the conservative approach is not associated with an increased incidence of death or reinfarction. Provision was not made in these studies, however, for evaluating the positive economic and psychologic impact of early coronary angiography, early hospital discharge, and early return to work of patients with a favorable postinfarction prognosis. It is concluded that early mechanical revascularization following thrombolysis should be considered for ongoing myocardial ischemia, but should otherwise be deferred pending the results of predischarge functional studies. For most patients, routine coronary angiography is likely to remain an important diagnostic tool and an integral component of the management of the convalescent phase of acute myocardial infarction.