Reperfusion therapy in acute myocardial infarction: present status and controversy.

Coronary thrombolysis revolutionized the treatment of acute myocardial infarction. Most of the experience was obtained with intravenous use of streptokinase and tissue-type plasminogen activator, the latter being superior to streptokinase in regard to coronary recanalization. Numerous other promising thrombolytic agents are being investigated. Both streptokinase and tissue-type plasminogen activator decreased mortality in large trials; comparison studies in terms of efficacy are presently being performed (GISSI 2). Aspirin is an important adjunct to thrombolytic therapy; it decreased mortality by itself (ISIS 2). Heparin is conventionally used together with thrombolysis. Its efficacy is under study (GISSI 2). Intracranial hemorrhage is the most devastating complication of thrombolysis. With the present dosage regimens, the incidence is approximately 0.5%. Percutaneous transluminal coronary angioplasty in conjunction with thrombolysis accomplished frequent and persistent recanalization of the infarct artery with low mortality, including high risk patients. The TIMI IIB study demonstrated that the results of a "conservative strategy" with aggressive management of recurrent ischemic events were comparable to those of an "invasive strategy." Subgroup analysis should, however, be awaited. High risk patients with low ejection fraction or with shock benefit by early mechanical coronary recanalization. The role of thrombolysis in the "late" stage of transmural myocardial infarction or in the acute ischemic syndrome (unstable angina/non-Q-wave myocardial infarction) is unclear and presently under investigation.