Association of same-day antiplatelet loading and outcomes after transcarotid artery revascularization

Prior studies have emphasized the importance of compliance with preoperative dual antiplatelet therapy (DAPT) in patients undergoing transcarotid artery revascularization (TCAR). This investigation examines differences in perioperative outcomes after TCAR in those receiving a loading dose of antiplatelet medications on the day of the procedure vs those already maintained on DAPT.

Consecutive TCAR procedures from the Vascular Quality Initiative (2016-2022) were identified. Patients were divided into (1) those on preoperative DAPT (aspirin and P2YI2 antagonist) taken at least within 36 hours of the procedure (61.9%); (2) those on at least one antiplatelet medication who received a supplemental dose of another antiplatelet within 4 hours before the procedure (AP + loading, 37.1%); and (3) patients receiving only a loading dose (of aspirin or P2Y12 antagonist) without prior use of antiplatelet therapy (1%). In-hospital and 30-day outcomes were compared between the three groups using univariable and multivariable analyses.

A total of 22,310 patients were on DAPT; 13,392 were on at least one antiplatelet and received a supplemental dose (AP + loading) and 361 patients received a loading dose on the day of the intervention. On univariable analysis, there was no significant difference in in-hospital or 30-day outcomes between the three groups, except for an increased rate of in-hospital stent thrombosis/occlusion in patients loaded with antiplatelet medications on the day of TCAR (n = 2 [0.6%]), compared with those maintained on DAPT (n = 23 [0.1%]) and patients in the AP + loading group (n = 26 [0.2%]) (P = .01). After adjusting for baseline differences between the three groups, no significant association was observed between the groups and in-hospital stroke/death or bleeding complications. However, compared with patients maintained on DAPT, patients receiving antiplatelet loading had higher odds of stent thrombosis/occlusion (odds ratio, 1.92; 95% confidence interval, 1.08-3.4; P = .03). Among patients in the AP + loading group, those maintained on aspirin preoperatively and receiving another antiplatelet loading on the day of the intervention were more likely to have stent thrombosis.

This study demonstrates that administering loading or supplemental doses of antiplatelet medication(s) to rapidly achieve therapeutic levels on the day of TCAR is not associated with higher rates of in-hospital stroke or bleeding complications. However, an increase in stent thrombosis or occlusion was noted in patients receiving a loading dose or supplementation of antiplatelet medications and warrants further investigation. In elective cases, it might be safer to delay intervention until patients receive adequate DAPT regimen, especially if patients are not maintained on P2Y12 inhibitors preoperatively.