Abstract 4723: Predictors of Local Persistent Hypercoagulability After Sirolimus-eluting Stent Implantation: Implication for Correlates of Late Stent Thrombosis
Purpose: We have previously demonstrated more increased local coagulative response after sirolimus-eluting stent (SES) implantation as compared to bare metal stent (BMS) implantation by measuring plasma levels of prothrombin fragment F1+2 (frF1+2). The predictors of local coagulability after SES implantation are not known. We investigated the predictors of local hypercoagulability following SES implantation.
Methods: Seventy-five consecutive patients, with no evidence of restenosis, were enrolled six months after stent implantation. Twenty-eight patients had been stented with BMS, 47 with SES. We measured plasma levels of frF1+2 sampled in coronary sinus (CS) and sinus of Valsalva (V). The transcardiac gradient (Δ) was defined as the CS level minus V level. Comparison of clinical and lesional features was made and multivariate analysis was also performed to identify independent predictors of local hypercoagulability in the SES group.
Results: ΔfrF1+2 was significantly greater in the SES group than in the BMS group (0.50±0.73 vs −0.14±0.21 nmol/l, p=0.02). According to the ΔfrF1+2, SES patients were classified into the two groups [hypercoagulative group (ΔfrF1+2 > −0.06 + 0.16 nmol/l, mean value + SD, n=12) and hypocoagulative group (ΔfrF1+2 <−0.06 − 0.16 nmol/l, mean value − SD, n=19)]. No administration of statin was more common (50 vs 12%, p<0.05), and larger percent diameter stenosis before coronary intervention (90 vs 80%, p<0.05) and longer total stent length (34±7.7 vs 23±10mm, p<0.01) were observed in the hypercoagulative group than in the hypocoagulative group. Multivariate analysis identified only longer total stent length as an independent predictor of local hypercoagulability (p<0.05).
Conclusions: An increased local coagulative response was observed long after SES implantation as compared to BMS. Our findings suggest that local persistent hypercoagulability related to late stent thrombosis remains in convalescent phase after longer SES implantation.