B-AB17-01 LEFT ATRIAL CLOSURE DEVICE THROMBOSIS IS ASSOCIATED WITH SYSTEMIC EMBOLIZATION

Abstract

Cardioembolic stroke and systemic embolism (CS/SE) represents the most severe complication of atrial fibrillation. Approximately 92% of intracardiac thrombosis originates from the left atrial appendage (LAA) and, although its mechanical occlusion is a proved method to prevent cardioembolism, thrombosis of all types of LAA occlusion devices and their associations with CS/SE were observed. The purpose of this study is to evaluate the rate of LAA occlusion device thrombosis, its predictors, and the risk for cardioembolism. We analyzed a group of 454 patients (65% male, mean age 72 years) with high risk for thromboembolism (mean CHADSVASc=4.0) after LAA catheter occlusion using any of 9 different occluder types since 2004. During clinical follow-up 1260 patient years were collected and an intracardiac thrombus was found on 24 devices. Total of 18 patients suffered CS/SE. Thrombosis was found in 11 men and 12 women, mean age 76 years, average CHADSVASc=4.5 and HASBLED=2.0. The thrombus was discovered on average 4.1 months after the LAA occlusion. In that time patients were receiving dual antiplatelet therapy (13x), acetylsalicic acid (6x), or interrupted anticoagulation (5x). In 3 cases the thrombosis was associated with CS/SE which represented risk of 6.6% per year. In patients with no thrombosis annual risk of CS/SE was only 1.7% (P<0.001). In our single center register thrombosis was found in total of 5.7% patients after LAA device implantation. In these patients, risk of CS/SE is 3.9-fold higher compared to patients without thrombus formation. Elderly patients and patients with more risk factors in general were affected more frequently.