Aspirin Monotherapy vs No Antiplatelet Therapy in Stable Patients With Coronary Stents Undergoing Low-to-Intermediate Risk Noncardiac Surgery

Abstract

Background: Current guidelines recommend the perioperative continuation of aspirin in patients with coronary drug-eluting stents (DES) undergoing noncardiac surgery. However, supporting evidence is limited.

Objectives: This study aimed to compare continuing aspirin monotherapy vs temporarily holding all antiplatelet therapy before noncardiac surgery in patients with previous DES implantation.

Methods: We randomly assigned patients who had received a DES >1 year previously and were undergoing elective noncardiac surgery either to continue aspirin or to discontinue all antiplatelet agents 5 days before noncardiac surgery. Antiplatelet therapy was recommended to be resumed no later than 48 hours after surgery, unless contraindicated. The primary outcome was a composite of death from any cause, myocardial infarction, stent thrombosis, or stroke between 5 days before and 30 days after noncardiac surgery.

Results: A total of 1,010 patients underwent randomization. Among 926 patients in the modified intention-to-treat population (462 patients in aspirin monotherapy group and 464 patients in the no-antiplatelet therapy group), the primary composite outcome occurred in 3 patients (0.6%) in the aspirin monotherapy group and 4 patients (0.9%) in the no antiplatelet group (difference, -0.2 percentage points; 95% CI: -1.3 to 0.9; P > 0.99). There was no stent thrombosis in either group. The incidence of major bleeding did not differ significantly between groups (6.5% vs 5.2%; P = 0.39), whereas minor bleeding was significantly more frequent in the aspirin group (14.9% vs 10.1%; P = 0.027).

Conclusions: Among patients undergoing low-to-intermediate risk noncardiac surgery >1 year after stent implantation primarily with a DES, in the setting of lower-than-expected event rates, we failed to identify a significant difference between perioperative aspirin monotherapy and no antiplatelet therapy with respect to ischemic outcomes or major bleeding. (Perioperative Antiplatelet Therapy in Patients With Drug-eluting Stent Undergoing Noncardiac Surgery [ASSURE-DES]; NCT02797548).

Keywords: antiplatelet therapy; aspirin; coronary artery disease; drug-eluting stent; noncardiac surgery.