Abstract 4484: Predictors of Early vs. Late Stent Thrombosis after Drug Eluting vs. Bare Metal Stent Implantation: A Protective Effect of High Dose Statin Therapy?

Abstract

Background: Several predictors of stent thrombosis (ST) after implantation of drug-eluting stents (DES) have been identified. However, no data is available on the differences between early vs. late ST despite their different pathophysiology. In addition, a direct comparison of predictors of ST after DES vs. bare metal stent (BMS) implantation is lacking. Methods: Baseline clinical and angiographic parameters and 3-year follow-up data of the Basel Kosten Effektivitäts Trial (BASKET; 826 patients randomized 2:1 to DES vs. BMS) were analyzed in univariate and multivariate models regarding early ST, i.e., ST on dual antiplatelet therapy with aspirin and clopidogrel in the first 6 months, and late ST, i.e., ST on aspirin only after the first 6 months (definite, probable, and possible). Separate analyses were done for DES and BMS. Results: Overall, there were 51 (9.0%) vs. 21 (7.5%) ST in DES vs. BMS treated patients (p=0.51). Multivariate predictors of early ST in DES (n=16) were the use of glycoprotein IIb/IIIa inhibitors (OR 6.65, 95% CI 1.80 –24.57; p=0.005), type C lesions (OR 5.46, 95% CI 1.73–17.23; p=0.004), 3-vessel disease (OR 4.77, 95% CI 1.49 –15.26; p=0.009), statin dose (OR 0.37 per quintile increase, 95% CI 0.19 – 0.74; p=0.005), and intervention in the right coronary artery (OR 0.14, 95% CI 0.03– 0.69; p=0.016), whereas the only multivariate predictor of early ST in BMS (n=11) was age (OR 1.05 per year increase, 95% CI 1.005–1.092; p=0.029). The only multivariate predictor of late ST in DES (n=35) was saphenous vein graft intervention (OR 6.74, 95% CI 2.85–15.85; p<0.0001), whereas multivariate predictors of late ST in BMS (n=10) were saphenous vein graft intervention (OR 5.23, 95% CI 0.92–29.75; p=0.062) and age (OR 1.098 per year increase, 95% CI 1.021–1.18; p=0.011). Conclusion: Early ST after DES implantation mainly depends on the complexity of the disease and the intervention, with the use of a higher statin dose possibly having a protective effect against early ST. The observation of a strong dose-dependent protective effect of statins to prevent early ST after DES is new, hypothesis-generating, and should be evaluated in an adequately powered prospective randomized trial.