3-YEAR FOLLOW-UP AFTER IMPLANTATION OF METALLIC CORONARY-ARTERY STENTS

Background. Coronary-artery stents are known to reduce rates of resten osis after coronary angioplasty, but it is uncertain how long this ben efit is maintained. Methods. We evaluated clinical and angiographic fo llow-up information for up to three years after the implantation of Pa lmaz-Schatz metallic coronary-artery stents in 143 patients with 147 l esions of native coronary arteries. Results, The rate of survival free of myocardial infarction, bypass surgery, and repeated coronary angio plasty for stented lesions was 74.6 percent at three years. After 14 m onths, revascularization of the stented lesion was necessary in only t hree patients (2.1 percent), In contrast, coronary angioplasty for a n ew lesion was required in 11 patients (7.7 percent), Follow-up coronar y angiography of 137 lesions at six months, 114 lesions at one year, a nd 72 lesions at three years revealed a decrease in minimal luminal di ameter from 2.54+/-0.44 mm immediately after stent implantation to 1.8 7+/-0.56 mm at six months, but no further decrease in diameter at one year (in patients with paired angiograms, 1.95+/-0.49 mm at both six m onths and one year), Significant late improvement in luminal diameter was observed at three years (in patients with paired angiograms, 1.94/-0.48 mm at six months and 2.09+/-0.48 mm at three years; P<0.001). C onclusions. Clinical and angiographic outcomes up to three years after coronary-artery stenting were favorable, with a low rate of revascula rization of the stented lesions. Late improvement in luminal diameter appears to occur between six months and three years.