Electrocardiographic changes after streptokinase-induced recanalization in patients with acute left anterior descending artery obstruction.

ECG changes were assessed in 15 patients in whom intracoronary streptokinase recanalized a totally occluded left anterior descending artery during acute myocardial infarction. These results were compared retrospectively with those in 22 comparable conventionally treated patients who underwent catheterization during the acute stage of infarction. Before angiography no significant differences were found in the sum of ST elevation (sigma ST increase V1-V6), the sum of R waves (sigma RV1-V6), or the number of Q waves (nQV1-V6) in leads V1 through V6. sigma ST increase V1-V6 was significantly lower in the streptokinase group than in control patients at all times after angiography. sigma RV1-V6 declined and nQV1-V6 increased in both groups during the first 12 hr, but there was no further change in the control group, whereas in the streptokinase group a significant increase in sigma RV1-V6 and decrease in nQV1-V6 followed. There was a significant correlation between long-term electrocardiographic (sigma RV1-V6; nQV1-V6) and angiographic findings (ejection fraction, akinetic segment length). Thus, the Q wave regression and increase in sigma RV1-V6 after streptokinase suggest, in accordance with angiographic findings, that jeopardized myocardium was salvaged by reperfusion.