Beneficial effects of mechanical reperfusion therapy on left ventricular remodeling and late outcome following myocardial infarction.

Abstract

The long-term relative benefits of thrombolysis and mechanical reperfusion therapy following acute myocardial infarction (AMI) have not been established. The purpose of this study was to compare left ventricular function, left ventricular remodeling and late outcome after AMI for different reperfusion therapies. Thirty consecutive patients suffering their first anterior wall myocardial infarction with coronary stenoses limited to the left anterior descending coronary artery were studied. They included 10 patients who underwent intracoronary thrombolysis (ICT), 10 who underwent PTCA and 10 who underwent noninterventional medical treatment. All patients underwent coronary angiography (CAG) during the acute phase of AMI and also during the follow-up period, and left ventriculography during the follow-up period and clinical follow-up was performed (mean clinical follow-up period: 53 +/- 31 months). No significant difference in global ejection fraction was noted among the groups, although the end-diastolic volume index (EDVI) in the PTCA group (79.4 +/- 17.5 ml/m2) was significantly smaller than in the noninterventional (106.1 +/- 25.1 ml/m2) and ICT (107.9 +/- 28.3 ml/m2) group (p < 0.05). The regional wall motion index (RWMI) for the anterior region in the PTCA group (-2.7 +/- 0.8) was greater (p < 0.05) than in the noninterventional (-3.4 +/- 0.6) and ICT (-3.3 +/- 0.6) groups. A significant linear correlation was found between EDVI and % diameter stenosis and also between RWMI and % diameter stenosis following reperfusion (p = 0.01). There was no difference in the incidence of cardiac death, nonfatal reinfarction, bypass surgery or congestive heart failure among the groups. Disturbed left ventricular regional wall motion and remodeling benefit most from angioplasty because of prompt restoration of adequate blood flow. However, there was no difference in late outcomes following AMI among the three groups.