Ischemic and Hemorrhagic Strokes after Left Atrial Appendage Occlusion (LAAO): A Mayo Clinic Case Series (3948)

Objective: To review peri- and post-procedural cerebrovascular outcomes after left atrial appendage occlusion (LAAO) with WATCHMAN across all Mayo Clinic sites. Background: In patients with atrial fibrillation, LAAO has become an important alternative for stroke prevention when long-term oral anticoagulants are not desired. The management and prevention of peri- and post-procedural cerebrovascular events are often of high complexity. The characteristics of strokes after LAAO require further investigation. Design/Methods: Using the Mayo Clinic institutional (including Minnesota, Arizona, Florida) National Cardiovascular Data Registry, all patients that received LAAO procedures between 1/6/2016 to 10/2/2019 were identified. In hospital and follow-up information for up to two years after the LAAO procedure were reviewed. Patients that developed new cerebrovascular events were identified and individual chart review was conducted. Results: A total of 255 patients received a LAAO procedure. Five (2.0 %) developed ischemic cerebrovascular events (4 ischemic strokes, 1 transient ischemic attack), and one had intracerebral hemorrhage (0.4%) 7 months post-procedure in the setting of seizure-related head trauma. Among all 6 patients, the average age was 77 years, mean CHA2DS2-VASc was 5.3 (range 4–7) and 2 were female. One ischemic stroke occurred immediately post-procedure, which was possibly related to peri-procedural air embolism versus cardioembolism. Other ischemic strokes and TIA occurred at 3, 5, 8 and 12 months after LAAO, while the patient was on dual antiplatelet therapy, clopidogrel only, aspirin only, and aspirin only respectively. The etiology was cardioembolism, with 2 patients having device-related thrombus. All 5 patients were put on warfarin or apixaban afterwards. Conclusions: The rates of cerebrovascular events after LAAO are low. The majority of ischemic strokes were cardioembolic, and developed beyond the recommended anticoagulation period of 45 days post-procedure. Future investigation is needed to determine the necessity of additional screening for intra-atrial thrombus, and the length of anticoagulation in high-risk patients. Disclosure: Dr. Chiang has nothing to disclose. Dr. Chao has nothing to disclose. Dr. Arsanjani has nothing to disclose. Dr. O’Carroll has nothing to disclose. Dr. David has nothing to disclose. Dr. Friedman has nothing to disclose. Dr. Munger has nothing to disclose. Dr. Alkhouli has nothing to disclose. Dr. Pollak has nothing to disclose. Dr. Yang has nothing to disclose.