Low-dose direct oral anticoagulation vs dual antiplatelet therapy after left atrial appendage occlusion: 1-year...

Area of Science:

• Cardiovascular Medicine
• Interventional Cardiology
• Thrombosis and Hemostasis

Background:

• Left atrial appendage occlusion (LAAO) is an alternative to oral anticoagulation for stroke prevention in atrial fibrillation.
• Optimal antithrombotic therapy post-LAAO remains debated, with initial studies comparing low-dose direct oral anticoagulation (LD-DOAC) and dual antiplatelet therapy (DAPT).

Purpose of the Study:

• To evaluate the 1-year outcomes of patients undergoing LAAO who were initially treated with LD-DOAC versus DAPT, focusing on efficacy and safety after transitioning to single antiplatelet therapy (SAPT).

Main Methods:

• A multicenter, randomized clinical trial (ADALA) enrolled 91 patients with atrial fibrillation and contraindications to oral anticoagulation.
• Participants received either LD-DOAC or DAPT for 3 months post-LAAO, followed by a mandatory switch to SAPT for all patients.
• The primary endpoint was a composite of thromboembolic events, device-related thrombus (DRT), or major bleeding at 1 year.

Main Results:

• The primary endpoint occurred significantly less frequently in the LD-DOAC group (9.1%) compared to the DAPT group (32.6%) at 1 year (P=.013).
• This reduction was primarily driven by a significant decrease in DRT (0% vs 11.6%; P=.023) in the LD-DOAC arm.
• Major bleeding was numerically lower in the LD-DOAC group (9.1% vs 19.6%; P=.167), and total bleeding events were significantly reduced (13.6% vs 37.0%; P=.013).

Conclusions:

• A 3-month regimen of LD-DOAC followed by SAPT demonstrated superior efficacy and safety compared to DAPT for 1 year post-LAAO, particularly in reducing early DRT.
• The observed reduction in DRT and bleeding events supports the use of LD-DOAC for 3 months followed by SAPT in high-risk patients post-LAAO.
• Complete resolution of DRT without bleeding complications was noted in all cases treated with LD-DOAC.