Antithrombotic therapy after left atrial appendage closure

Abstract

It is important to prevent on-device thrombus formation without increasing the risk for bleeding complications after successful interventional left atrial appendage closure. Therefore, choosing the optimal antithrombotic therapy poses a challenging task. While major clinical studies investigated patients eligible for oral anticoagulation using vitamin K antagonists, the vast majority of implants in ‘real life’ are performed in patients with contraindications to oral anticoagulation after serious bleeding events. In this patient population, strategies using dual antiplatelet therapy were found to be a sound alternative; however, the optimal duration of antithrombotic therapy remains unclear. Future studies will have to investigate the role of direct anticoagulants for post-implant thrombus formation and address the question of whether left atrial appendage closure obviates the need for long-term aspirin therapy.

Keywords:

• antithrombotic therapy
• atrial fibrillation
• left atrial appendage
• occlusion
• stroke

Financial & competing interests disclosure

B Schmidt serves as a Consultant to St. Jude Medical and Boston Scierntific. The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

Key issues

• In patients without contraindications to oral anticoagulation, the post-implant antithrombotic therapy includes lifelong ASA, 6 weeks of vitamin K anticoagulation and clopidogrel from day 45 to 6 months.

• In patients with contraindications to oral anticoagulation, dual-platelet inhibition therapy for 6 weeks to 6 months appears effective and safe in preventing on-device thrombus.

• The optimal duration of antithrombotic therapy remains to be determined.

• It must be the ultimate goal to eliminate any antithrombotic therapy after left atrial appendage closure, but the feasibility of dispensing ASA remains to be tested in clinical trials.

• In case of on-device thrombus formation, low-molecular-weight heparin for 4–8 weeks is the most commonly used therapy.

• In the era of direct anticoagulants, prospective randomized clinical studies will have to compare the performance of left atrial appendage closure with these drugs.