Coronary angioplasty with or without stent implantation for acute myocardial infarction

Background: Coronary-stent implantation is frequently performed for treatme nt of acute myocardial infarction. However, few studies have compared stent implantation with primary angioplasty alone. Methods: We designed a multicenter study to compare primary angioplasty wit h angioplasty accompanied by implantation of a heparin-coated Palmaz-Schatz stent. Patients with acute myocardial infarction underwent emergency cathe terization and angioplasty. Those with vessels suitable for stenting were r andomly assigned to undergo angioplasty with stenting (452 patients) or ang ioplasty alone (448 patients). Results: The mean (+/-SD) minimal luminal diameter was larger after stentin g than after angioplasty alone (2.56+/-0.44 mm vs. 2.12+/-0.45 mm, P<0.001) , although fewer patients assigned to stenting had grade 3 blood flow (acco rding to the classification of the Thrombolysis in Myocardial Infarction tr ial) (89.4 percent, vs. 92.7 percent in the angioplasty group; P=0.10). Aft er six months, fewer patients in the stent group than in the angioplasty gr oup had angina (11.3 percent vs. 16.9 percent, P=0.02) or needed target-ves sel revascularization because of ischemia (7.7 percent vs. 17.0 percent, P< 0.001). In addition, the combined primary end point of death, reinfarction, disabling stroke, or target-vessel revascularization because of ischemia o ccurred in fewer patients in the stent group than in the angioplasty group (12.6 percent vs. 20.1 percent, P<0.01). The decrease in the combined end p oint was due entirely to the decreased need for target-vessel revasculariza tion. The six-month mortality rates were 4.2 percent in the stent group and 2.7 percent in the angioplasty group (P=0.27). Angiographic follow-up at 6 .5 months demonstrated a lower incidence of restenosis in the stent group t han in the angioplasty group (20.3 percent vs. 33.5 percent, P<0.001). Conclusions: In patients with acute myocardial infarction, routine implanta tion of a stent has clinical benefits beyond those of primary coronary angi oplasty alone. (N Engl J Med 1999;341:1949-56.) (C)1999, Massachusetts Medi cal Society.