Potentially increased incidence of scaffold thrombosis in patients treated with Absorb BVS who terminated DAPT before 18 months

Aims: The aim of this study was to investigate the impact of dual antiplatelet therapy (DAPT) termination on late and very late scaffold thrombosis (ScT) in patients treated with the Absorb bioresorbable vascular scaffold (BVS).
Methods and results: Data from the registries of three centres were pooled (808 patients). To investigate the effect of DAPT termination on ScT after a minimum of six months, we selected a subgroup ("DAPT study cohort" with 685 patients) with known DAPT status >6 months and excluded the use of oral anticoagulants and early ScT. In this cohort, definite/probable ScT incidence for the period on DAPT was compared to ScT incidence after DAPT termination. ScT incidence was 0.83 ScT/100 py with 95% confidence interval (CI): 0.34-1.98. After DAPT termination, the incidence was higher (1.77/100 py; 95% CI: 0.66- 4.72), compared to the incidence on DAPT (0.26/100 py, 95% CI: 0.04-1.86; p=0.12) and increased within the month after DAPT termination (6.57/100 py, 95% CI: 2.12-20.38; p=0.01). No very late ScT occurred in patients who continued on DAPT for a minimum of 18 months.
Conclusions: The incidence of late and very late definite/probable ScT was acceptable. The incidence was low while on DAPT but potentially higher when DAPT was terminated before 18 months.