LATE BREAKING ANDES TRIAL AT TCT 2025: DOACs Offer Safer Profile but No Added Efficacy in Preventing Device-Related Thrombosis After LAAO
Short-term use of direct oral anticoagulants (DOACs) following left atrial appendage closure (LAAC) did not significantly reduce device-related thrombosis (DRT) compared with dual antiplatelet therapy (DAPT). However, DOACs were associated with a notably better safety profile, primarily due to reduced bleeding events, based on findings from the ANDES trial presented at TCT 2025, San Francisco and simultaneously published in Circulation.
The ANDES trial, the largest of its kind, was conducted across 13 centers in Canada and Europe between 2018 and 2025. Led by Dr. Josep Rodés-Cabau of Laval University, Quebec, the study aimed to identify the optimal short-term antithrombotic strategy following LAAC in patients with non-valvular atrial fibrillation (NVAF). LAAC is increasingly used as an alternative to long-term oral anticoagulation for stroke prevention, yet the best post-procedural regimen to prevent device thrombosis remains uncertain.
In this trial, 510 patients (mean age 77 years, 35% women) undergoing LAAC were randomized to receive either DOACs or DAPT (aspirin plus clopidogrel) for 60 days. Transesophageal echocardiography (TEE) was performed at 60 days, with images analyzed in a blinded central core laboratory. The primary endpoint was the incidence of device-related thrombosis as confirmed by TEE, while safety outcomes included all-cause mortality, stroke, bleeding, or site-reported DRT.
Results showed that DRT occurred in 1.5% of patients in the DOAC group and 4.1% in the DAPT group, a difference that did not reach statistical significance (p=0.11). However, DOAC-treated patients had significantly fewer safety events (22.5% vs. 34.9%; p=0.003), a benefit driven largely by lower bleeding rates (17.4% vs. 24.9%; p=0.038). Stroke and mortality rates were low and comparable between groups. Most bleeding events were gastrointestinal in origin.
While DOACs did not outperform DAPT in reducing DRT, the investigators noted that the safer bleeding profile supports DOACs as a reasonable alternative, especially for patients at high bleeding risk. "While waiting for further evidence, these findings suggest that the short-term use of DOAC may be a reasonable and likely safer antithrombotic strategy in LAAO recipients," said Josep Rodés-Cabau, MD, PhD, while presenting the findings.
The authors acknowledged several limitations, including missing TEE data in 22% of participants and potential underpowering due to narrower-than-expected differences between groups. Additionally, the study’s 60-day follow-up may have underestimated late thrombotic or stroke events.
The ANDES trial underscores that while DOACs may not further reduce thrombotic complications after LAAC, they provide a safer alternative to DAPT, potentially shaping future recommendations for short-term antithrombotic management in this high-risk population.
Reference: Rodés-Cabau et al., Short-Term Anticoagulation versus Dual Antiplatelet Therapy for Preventing Device Thrombosis Following Left Atrial Appendage Closure: The ANDES Randomized Clinical Trial, TCT Conference 2025, San Francisco.
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