Background: Previous studies have suggested that restenosis and reocclusion occur frequently in patients with acute coronary syndromes. This study was undertaken to assess the incidence and predictors of restenosis in a cohort of patients who underwent successful primary coronary angioplasty for acute myocardial infarction.
Methods: Three hundred twelve patients who underwent successful primary angioplasty of a native coronary vessel were candidates for follow-up coronary angiography. This was performed in 284 patients (92%) at the 3- or 6-month follow-up. Quantitative coronary angiography was performed with the CMS system. Multivariate analysis was performed to determine independent predictors of restenosis.
Results: Restenosis, defined as a diameter stenosis of >50%, occurred in 27% of patients at 3 months and in 37% of patients at 6-month follow-up. Reocclusion occurred in 4% and 6%, respectively. Reference diameter (vessel size) was related to restenosis. Age and lumen diameter immediately after angioplasty were independent predictors of restenosis. Young patients (<50 years) and patients with a minimal luminal diameter of more than 2.5 mm had restenosis rates of <25%. The radionuclide ejection fraction was 46% in patients with restenosis compared with 47% in patients without restenosis.
Conclusions: The incidence of restenosis after successful primary coronary angioplasty for acute myocardial infarction is comparable to the reported incidence after elective coronary angioplasty for stable angina. Restenosis is related to age and the lumen diameter after angioplasty and does not affect left ventricular function in this population.