Optimal dual antiplatelet therapy duration for bioresorbable scaffolds: an individual patient data pooled analysis of the ABSORB trials.

Abstract

Compared with everolimus-eluting metallic stents, the Absorb bioresorbable scaffold (BRS) results in increased rates of myocardial infarction (MI) and scaffold thrombosis (ST) during its three-year bioresorption phase. It is unknown whether prolonged dual antiplatelet therapy (DAPT) duration might decrease the risk of ischaemic events. We sought to evaluate the impact of DAPT duration on ischaemic and bleeding outcomes following BRS implantation. We conducted an individual patient data pooled analysis from four ABSORB randomised trials and one prospective ABSORB registry. Study endpoints were MI, ST, bleeding, and death up to three-year follow-up. Propensity score-adjusted Cox regression analysis was used to account for baseline differences related to DAPT duration. The five ABSORB studies included 2,973 patients. DAPT use was 91.7%, 53.2%, and 48.0% at 1, 2, and 3 years, respectively. DAPT use within the first year after BRS implantation was associated with markedly lower risks of MI (adjusted hazard ratio [aHR] 0.17, 95% CI: 0.10-0.32; p<0.0001) and ST (aHR 0.08, 95% CI: 0.03-0.19; p<0.0001). Conversely, DAPT use between 1 and 3 years did not significantly affect the risk of MI (aHR 1.04, 95% CI: 0.70-1.55; p=0.84) or ST (aHR 0.86, 95% CI: 0.42-1.75; p=0.67). DAPT did not have major effects upon bleeding or death in either period. DAPT use during the first year after BRS implantation was strongly associated with lower risks of ST and MI. However, a benefit of ongoing DAPT use between 1 and 3 years after BRS implantation was not apparent.