Residual stroke risk after left atrial appendage closure in patients with prior oral anticoagulation failure

Abstract

Background: Patients with atrial fibrillation (AF) and oral anticoagulation (OAC) failure may benefit from left atrial appendage closure (LAAC), however, the evidence is scarce. We report outcomes of LAAC in patients with OAC failure compared to those with classic indications of OAC contraindications.

Methods: Prospective registry of LAAC with Amplatzer or WATCHMAN device followed by dual antiplatelet therapy (DAPT) was analyzed (05.2014-11.2019). The study group included patients with OAC failure defined as stroke/TIA/PE/LAA thrombus (n = 39) during OAC, whereas the control group consisted of patients with OAC contraindications (n = 156). Structured follow-up at 3, 6, and 12 months was done.

Results: The study group compared to controls was younger [73 (IQR, 62-77) vs 74 (IQR, 68-81) years, P = 0.046], with higher CHA₂DS₂-VASc [5.0 (IQR, 3.0-6.0) vs 4.0 (IQR, 3.0-5.0), P = 0.001)], lower HAS-BLED [2.0 (IQR, 1.0-3.0) vs 3.0 (IQR, 2.0-3.0), P = 0.006] and similar proportion of WATCHMAN implantations (43.6% vs 44.2%, P = 1.000). The reduction from CHA₂DS₂-VASc predicted to observed annual stroke/TIA/PE rate was markedly smaller in the study vs control group (14% vs 77%) with 10.3% vs 1.9% stroke/TIA/PE respectively (P = 0.031). The reduction from HAS-BLED predicted to observed annual major nonprocedural bleeding rate was higher (100% vs 7.4%) with 0.0% vs 5.1% major bleedings respectively (P = 0.361). The device-related thrombosis remained similar (13.2% vs 11.3%, P = 0.778).

Conclusions: Patients after LAAC for OAC failure and unremarkable prior bleeding history presented with high residual stroke and low bleeding risks. Therefore concomitant long-term OAC or prolonged DAPT should strongly be considered in this population.

Keywords: Atrial fibrillation; Left atrial appendage closure; Stroke; Thromboembolism.