Randomized Trial of Aspirin Versus Warfarin After Transcatheter Aortic Valve Replacement in Low-Risk Patients

Abstract

Background: The optimal antithrombotic regimen after transcatheter aortic valve replacement remains unclear. Methods: In this randomized open-label study, low-risk patients undergoing transfemoral transcatheter aortic valve replacement at 7 centers in the United States were randomized 1:1 to low-dose aspirin or warfarin plus low-dose aspirin for 30 days. Patients who could not be randomized were enrolled in a separate registry. Computed tomography or transesophageal echocardiography was performed at 30 days. The primary effectiveness end point was a composite of the following at 30 days: hypoattenuated leaflet thickening, at least moderately reduced leaflet motion, hemodynamic dysfunction (mean aortic valve gradient ≥20 mm Hg, effective orifice area ≤1.0 cm 2 , dimensionless valve index <0.35, or moderate or severe aortic regurgitation), stroke, or transient ischemic attack. Results: Between July 2018 and October 2019, 94 patients were randomly assigned, 50 to aspirin and 44 to warfarin plus aspirin, and 30 were enrolled into the registry. In the intention-to-treat analysis of the randomized cohort, the composite primary effectiveness end point was met in 26.5% for aspirin versus 7.0% for warfarin plus aspirin ( P =0.014; odds ratio, 4.8 [95% CI, 1.3–18.3]). The rate of hypoattenuated leaflet thickening was 16.3% for aspirin versus 4.7% for warfarin plus aspirin ( P =0.07; odds ratio, 4.0 [95% CI, 0.8–20.0]). There was no excess bleeding at 30 days with anticoagulation. In the as-treated analysis of pooled randomized and registry cohorts, the rate of hypoattenuated leaflet thickening was 16.7% for aspirin versus 3.1% for warfarin plus aspirin ( P =0.011; odds ratio, 6.3 [95% CI, 1.3–30.6]). Conclusions: In low-risk transcatheter aortic valve replacement patients, anticoagulation with warfarin may prevent transcatheter heart valve dysfunction in the short term without excess bleeding. Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT03557242.

Valve thrombosis after transcatheter and surgical aortic valve replacement: Incidence and outcomes

“…Although oral anticoagulation has been demonstrated to reduce the incidence of leaflet thrombosis (Table 2), 33,34 routine use of oral anticoagulation after TAVR appears to lead to excess bleeding which outweighs antithrombotic effects. The GALILEO study evaluated the role of rivaroxaban 10 mg daily (alongside aspirin 75-100 mg daily for 3 months), compared with aspirin 75 to 100 mg daily (with clopidogrel 75 mg daily for 3 months) in patients undergoing TAVR without an established indication for anticoagulation.…”

Antithrombotic Therapy After Transcatheter Aortic Valve Replacement: An Overview

“…Anticoagulation therapy has also been observed to reduce or prevent subclinical and clinical valve thrombosis in several observational studies using different doses and types of OACs. 31,60,[74][75][76][77] In a meta-analysis by Woldendorp et al 77 including 3456 patients with 11.5% having SCVT, OAC therapy was found to be superior to SAPT or DAPT in protecting against SCVT (p < 0.0001). However, this study presents observational data, did not analyze bleeding outcomes, and did not have a uniform CT follow-up.…”

Aortic stenosis and Heyde’s syndrome: A comprehensive review

“…Recent randomized control trials in TAVR have questioned the use of DAPT against single anti platelet therapy (SAPT), with less bleeding risk with SAPT and no difference in thromboembolic events[ 60 - 63 ]. In a recent randomized trial on TAVR in low risk patients, the use of low dose aspirin plus warfarin did not increase short-term bleeding (30 d)[ 64 ]. The option of SAPT with TAVR seems to be promising, especially in the setting of Heyde’s syndrome.…”