Effects of spontaneous and streptokinase-induced recanalization on left ventricular function after myocardial infarction.

The effect of recanalization of the "infarct vessel" on left ventricular (LV) function was assessed 6-8 weeks after acute myocardial infarction (MI) in two groups: patients who had streptokinase-induced recanalization during the acute phase and control patients who had spontaneous recanalization. The ejection fraction and severity of LV wall motion abnormalities in 100 patients with recanalization were compared with those in 78 patients with persistent occlusion of the infarct vessel. Among patients with inferior MI, LV function was significantly better in those with spontaneous (n = 41, p less than 0.05) and streptokinase-induced recanalization (n = 15, p less than 0.02) than in those with persistent occlusion of the infarct vessel (n = 40) in the control group. The LV function was equally good in patients with spontaneous and streptokinase-induced recanalization. Among anterior MI patients, LV function was significantly better in those with streptokinase-induced recanalization (n = 10) than in those with spontaneous recanalization (n = 34, p less than 0.01) or persistent occlusion in the control group (n = 28, p less than 0.001). We conclude that recanalization has a beneficial effect on LV function in patients with MI.