Long-term follow-up of patients treated with coronary angioplasty for acute myocardial infarction

Abstract

Long-term follow-up data for patients treated with coronary angioplasty (PTCA) for acute myocardial infarction are limited. Therefore the long-term outcome of 336 consecutive patients treated with PTCA at a median of 4.5 hours (range 0.5 to 48 hours) from symptom onset was evaluated. The in-hospital mortality was 11.1% (37 patients). Follow-up is complete for 293 of 299 (98%) hospital survivors at a median of 24 months. Of patients discharged, the mean age was 55 +/- 11 years, 49% received intravenous thrombolytic therapy, 53% had multivessel coronary artery disease, and the mean ejection fraction was 48 +/- 10%. Post-discharge survival was 96.1% at 1 year and 93.6% at 2 years by life table analysis. Post-discharge survival was independently predicted by no prior myocardial infarction (96.9% versus 87.3% 2-year survival, p p = 0.02]). For patients with analyzable ventriculograms at hospital discharge, ejection fraction >= 40% was also a significant independent predictor of survival (98.1% versus 85.8% 2-year survival, p = 0.01). For patients with a successful PTCA, time from symptom onset to catheterization and angioplasty 4 hours was also an independent predictor of outcome (97.1% versus 91.4% 2-year survival; p = 0.04). Freedom from recurrent myocardial infarction was achieved in 95.2% of patients at 1 year and in 93.1% at 2 years. The only independent predictors of recurrent nonfatal myocardial infarction were a history of diabetes mellitus (p = 0.004), and multivessel coronary artery disease (p = 0.03). During follow-up, 7.1% of patients had repeat PTCA and 11.0% had coronary artery bypass surgery. Independent predictors of late revascularization were a history of prior myocardial infarction and an age p < 0.05). At latest follow-up, 27.3% of patients reported symptoms of angina pectoris (mean angina CLASS = 1.8 +/- 0.8). The only independent predictor of late angina was a closed infarct artery at hospital discharge. We conclude that post-discharge survival in this group of patients trreated with angioplasty in the setting of an acute myocardial infarction was 93% at 2 years, and that survival may be as high as 97% in patients without prior myocardial infarction and in patients treated successfully within 4 hours of symptom onset. Further symptoms of ischemia are not uncommon despite an 18% incidence of repeat angioplasty or bypass surgery at 2 years' time.