Bare metal stent thrombosis in patients with acute coronary syndrome.

Background: Patients undergoing coronary stenting during acute coronary syndrome (ACS) are exposed to a higher risk of stent thrombosis (ST) than those undergoing elective stenting. FEW STUDIES HAVE AIMED TO IDENTIFY ST INCIDENCE AND PREDICTORS IN THIS SPECIFIC POPULATION.
Methods and Results: This single-center study enrolled 611 consecutive Tunisian patients with ACS who underwent coronary stenting with bare metal stents (BMS). The incidence of ARC (Academic Research Consortium) definite ST throughout a median 16-month follow-up period was 3.5%; it was 9.2% in patients with ST-elevation myocardial infarction (STEMI) who underwent an emergency percutaneous coronary intervention (PCI). Independent predictors were fever during PCI (hazard ratio (HR) 5.19; 95% confidence interval (95%CI) 1.69-15.95, P=0.004); premature cessation of clopidogrel (HR 2.66; 95%CI 1.02-6.97, P=0.046), resumption of smoking (after PCI) (HR 4.41; 95%CI 1.58-12.27, P=0.005), primary PCI (HR 5.02; 95%CI 1.57-16.01, P=0.006), rescue PCI (HR 6.33; 95%CI 2.08-19.34, P=0.001), reference vessel diameter <2.8mm (HR 6.96; 95%CI 2.06-23.56, P=0.002), TIMI flow grade before PCI <2 (HR 11.51; 95%CI 2.76-48.06, P=0.001) and a visible thrombus (HR 3.57; 95%CI 1.1-11.12, P=0.028).
Conclusions: The incidence of ST in ACS patients was higher than classically described. Clopidogrel discontinuation and resumption of smoking are involved. Efforts should be made to improve patient education and secondary prevention.