In acute myocardial infarction, myocardial salvage is dependent on rapid restoration of blood flow. Pharmacologic (streptokinase, recombinant tissue-type plasminogen activator), mechanical (percutaneous transluminal coronary angioplasty, guide wire perforation) or combined forms of reperfusion therapy can accomplish this goal, but their effects on infarcted myocardium and vessel occlusion site have not been compared at necropsy. The heart of 19 necropsy patients who had received various forms of acute reperfusion therapy was studied: 14 had pharmacologic or combined forms of reperfusion therapy (13 streptokinase and 1 tissue-type plasminogen activator, including 4 with combined balloon angioplasty) and 5 had had purely mechanical (balloon angioplasty) reperfusion therapy. Reperfusion was initially clinically successful in all 19 patients with the average time from onset of symptoms to reperfusion being 3.7 hours. Necropsy observations separated the 19 patients into distinct subgroups based on changes in the myocardium and infarct-related coronary arteries. Of the 19 patients, 14 (74%) had hemorrhagic myocardial infarction and they all received pharmacologic or combined forms of reperfusion therapy. The remaining five patients (26%) had nonhemorrhagic (anemic) infarction and were treated with balloon angioplasty therapy alone. Increased luminal cross-sectional area was present in 8 of 9 patients with acute balloon angioplasty but severe coronary atherosclerotic plaque remained in 9 of 10 patients without acute balloon angioplasty. Severe hemorrhage surrounded angioplasty sites in all four patients who also received streptokinase or tissue-type plasminogen activator. Severe bleeding at the angioplasty site compromised the dilated coronary lumen in one patient. No patient with angioplasty alone had intraplaque bleeding. Thus, acute coronary balloon angioplasty reperfusion therapy alone appears to avoid the potentially adverse effects of myocardial and intraplaque hemorrhage while simultaneously increasing luminal cross-sectional area at the site of acute occlusion.