Is spontaneous echo contrast associated with device-related thrombus or embolic events after left atrial appendage occlusion?-Insights from the multicenter German LAARGE registry

BackgroundInterventional left atrial appendage occlusion (LAAO) provides an alternative to oral anticoagulation (OAC) for prophylaxis of thromboembolic events (TEs) in nonvalvular atrial fibrillation patients, predominantly in those with high bleeding risk and contraindications for long-term OAC. Although spontaneous echo contrast (SEC) is a well-known risk factor for atrial thrombus formation, little is known about whether this means an increased risk of device-related thrombus (DRT) or TEs following LAAO.MethodsThis substudy of the prospective, multicenter German LAARGE registry assessed two groups according to absence (SEC -) or presence of SEC (SEC +) in preprocedural cardiac imaging. Clinical and echocardiographic parameters were registered up to 1 year after LAAO.ResultsFive hundred eighty-eight patients (SEC - 85.5 vs. SEC + 14.5%) were included. More SEC + patients were implanted for OAC non-compliance (11.8 vs. 4.6%, p = 0.008) and a higher proportion received only antiplatelet therapy without OAC at hospital discharge (96.5 vs. 86.0%, p = 0.007). The SEC + patients had larger LA diameters (50 (47; 54) vs. 47 (43; 51) mm, p < 0.001), wider LAA ostia (21 (19; 23) vs. 20 (17; 22) mm at 45 degrees, p = 0.011), and lower left ventricular ejection fraction (50 (45; 60) vs. 60 (50; 60) %, p < 0.001) on admission. Procedural success was very high in both groups (98.1%, p = 1.00). Periprocedural major adverse cardiac and cerebrovascular events and other major complications were rare in both groups (3.8 vs. 4.7%, p = 0.76). At follow-up, DRT was only detected in the SEC - group (3.8 vs. 0%, p = 1.00). The rates of TEs (SEC - 1.2 vs. SEC + 0%, p = 1.00) after hospital discharge and 1-year mortality (SEC - 12.0 vs. SEC + 11.8%, p = 0.96) were not significantly different between the two groups.ConclusionsPresence of SEC at baseline was not associated with an increased rate of DRT or TEs at 1-year follow-up after LAAO in LAARGE.