Intracoronary streptokinase thrombolytic recanalization and subsequent surgical bypass of remaining atherosclerotic stenosis in acute myocardial infarction: Complementary combined approach effecting reduced infarct size, preventing reinfarction, and improving left ventricular function

Abstract

In 48 patients with acute myocardial infarction (AMI) the acutely thrombus-occluded coronary artery was successfully recanalized nonsurgically via catheter with intracoronary streptokinase (SK) infusion after a mean occlusion time of 3.1 ± 1.6 hours. In all cases residual high-grade fixed atherosclerotic stenosis remained after percutaneous transluminal coronary recanalization (PTCR). Subsequent aortocoronary bypass surgery (ACBS) circumventing the stenotic coronary artery was performed during the acute stage of myocardial infarction (within 10 days of AMI onset) in 34 patients and electively (longer than 10 days after AMI onset) in 14 patients. No patient died from early PTCR or from ACBS intervention. There were two late post-ACBS arrhythmogenic deaths, two patients suffered nonfatal reinfarction post ACBS several months after hospital discharge, only two had occasional post-ACBS angina pectoris, and one patient had post-ACBS mild heart failure. The remaining 41 post-ACBS patients were completely asymptomatic throughout long-term follow-up evaluation. In the left ventricular (LV) segment supplied by the initially occluded coronary artery, which was recanalized early by means of SK therapy and subsequently grafted, wall motion improved significantly from the acute to the postoperative stage in patients who underwent early surgery (from 13.6% ± 1.9% to 40.3% ± 2.7%, p < 0.001) and in the electively operated group (from 18.0% ± 7.1% to 48.2% ± 6.3%, p < 0.001). Ischemic wall motion was improved irrespective of whether or not the bypass graft circumventing the residual stenosis of the infarct vessel remained patent. Wall motion of nonischemic segments remained essentially unchanged. In the patients who underwent surgery in the early stage, the closure rate of the bypass graft to the infarct-related vessel was 17%, and in the electively operated group no graft was found to be occluded. In conclusion, coronary artery recanalization, achieved by means of early SK-PTCR therapy with subsequent ACBS, can be performed safely in patients with AMI, and the result will be marked improvement in LV segmental wall motion and global function, diminished reinfarction rate, and reduced incidence of angina pectoris, all benefits that are consistently maintained during long-term evaluation.