[Myocardial free wall rupture and thrombolytic therapy in acute myocardial infarction]

We investigated the relation between myocardial free wall rupture and thrombolytic therapy in 200 patients with acute myocardial infarction (AMI). Ten of 200 patients (5.0%) were complicated with cardiac rupture, and all of them died within 70 hours after the onset (29% of the deceased after AMI). The pathophysiologic study of 5 patients undergoing autopsy after cardiac rupture was performed. In 4 patients receiving thrombolysis, autopsy revealed massive hemorrhagic infarction and teared lesion near the center of infarcted area. We assessed that the location of teared lesion might be influenced by broad hemorrhagic infarcted area following thrombolytic therapy. The incidence of cardiac rupture was slightly higher in the group receiving thrombolysis in the early stage of AMI than conventional treatment group. Among the patients receiving thrombolytic therapy, some cases revealed markedly increased fibrinolytic activity. This suggested that such elevated fibrinolytic activity might induce massive hemorrhagic infarction and might be an important factor contributing to the cardiac rupture. Thrombolytic therapy has been frequently reported to improve cardiac function and prognosis, but our study suggests that thrombolytic therapy must be evaluated moreover as one of the risk factors of cardiac rupture.