Predictors of stent thrombosis after primary stenting for acute myocardialinfarction

The aim of the study was to determine if a hypercoagulable state that may p ersist for several months after an acute myocardial infarction may contribu te to an increased incidence of stent thrombosis. Primary stenting was perf ormed in 104 consecutive patients with acute myocardial infarction using 14 7 coronary stents. Twenty-eight patients (27%) were diabetic and 55 patient s (53%) were smokers. A single stent was placed in 63%, two stents in 33%, and more than two stents in 4% of the patients. Procedural success was obta ined in 97% of the patients. All stents were deployed using high-pressure b alloon inflation. The reference vessel diameter and minimal lumen diameter after stent deployment were 3.30 +/- 0.42 and 3.23 +/- 0.42 mm, respectivel y. Six patients (5.7%) developed stent thrombosis within 1 month after the procedure complicated by reinfarction in five of the six patients. At 1-mon th follow-up, all patients remained alive. On multivariate analysis, indepe ndent predictors of stent thrombosis were diabetes mellitus (relative risk [RR] 5.2; 95% confidence interval [CI] 1.8, 25.1), tobacco use (RR 4.5; 95% CI 1.3, 24.5), number of stents: 1 vs. > 1 (RR 3.7; 95% CI 1.1, 15.9), min imal lumen diameter poststent placement (RR 0.03; 95% CI 0.0002, 0.74), and duration of chest pain before intervention (RR 1.1; 95% CI 1.01, 1.25), St ent thrombosis had not been associated with diabetes mellitus and tobacco u se previously but is in agreement with the enhanced platelet aggregability, coagulation factor abnormalities, and impaired fibrinolysis characteristic of these patients. Cathet Cardiovasc. Intervent. 47:415-422, 1999. (C) 199 9 Wiley-Liss, Inc.