Stent thrombosis: insights on outcomes, predictors and impact of dual antiplatelet therapy interruption from the SPIRIT II, SPIRIT III, SPIRIT IV and COMPARE trials

AIMS: Recent studies have suggested that EES may reduce ST compared to PES, but no individual trial has been adequately powered for this endpoint. The incidence of stent thrombosis, as well as the impact of dual antiplatelet therapy (DAPT) discontinuation during the first two years following everolimus-eluting stent (EES) and paclitaxel-eluting stent (PES) deployment were therefore analysed from a pooled, patient-level database derived from four randomised clinical trials. METHODS AND RESULTS: Data from the SPIRIT II, SPIRIT III, SPIRIT IV and COMPARE trials (n=6,789 patients) were analysed. Two-year ST rates were determined using time-to-event methods and compared with the log-rank test. ST rates were also determined after DAPT discontinuation. EES compared to PES significantly reduced the two-year rates of ST (0.7% versus 2.3%, p=0.0001), including the interval rates of ST up to 30 days (0.2% versus 1.0%, p<0.0001), between 31 days and one year (0.2% versus 0.6%, p=0.02), and after one year (0.3% versus 0.8%, p=0.001). EES also reduced the two-year composite rate of cardiac death or MI (4.0% versus 6.6%, p=0.0001). Increased rates of ST after DAPT discontinuation beyond six months were observed in the PES cohort, but not in the EES cohort. CONCLUSION: In this large pooled analysis from four randomised trials, treatment with EES compared to PES significantly reduced the rates of ST through two years of follow-up, with a concomitant reduction in cardiac death or MI. DAPT discontinuation beyond six months may be safe with EES.