Abstract TMP76: Left Atrial Appendage Closure In Atrial Fibrillation Patients At High Intracranial Hemorrhage Risk

Background: Lifelong oral anticoagulant (OAC) use is associated with higher intracranial hemorrhage (ICH) risk in nonvalvular atrial fibrillation (NVAF) patients. We aimed to assess the long-term outcomes of left atrial appendage closure (LAAC) in NVAF patients at high baseline ICH risk, as LAAC was FDA-approved for NVAF patients who have a reasonable rationale to seek a nonpharmacological alternative to lifelong OAC use. Methods: We collected baseline and follow up data from consecutive NVAF patients who had LAAC because of either past ICH or finding cerebral microbleeds (CMB) on MRI without ICH (CMB-only). The outcome measures were the occurrence of ICH or acute ischemic stroke (AIS) after LAAC. Results: Out of a total of 644 LAAC performed in a single hospital system between 2015-2022, 142 NVAF patients had LAAC with WATCHMAN because of past ICH or CMB-only. Their mean age was 75.8± 7.6, 41 were female (29%). Mean CHA 2 DS 2 -VASc score was 5.24±1.4. Of the 142 patients, 67 (47.2%) had intraparenchymal hemorrhage (IPH, 52% related to cerebral amyloid angiopathy [CAA]), 19 (13.4%) had non-traumatic subdural hemorrhage (SDH), 36 (25.3%) had traumatic ICH (T-ICH), and 20 (14.08%) were CMB-only (65% with CAA pattern). Eighty-one patients were discharged on OAC (57%) and 133 patients were not taking OAC at 1 year (94%). Over a mean 1.98 years follow up, one patient had recurrent non-traumatic IPH (incidence rate [IR] 0.36 per 100 patient-years), four had traumatic ICH/SDH due to severe falls (IR 1.4%/year), and five had AIS (IR 1.78%/year). Conclusions: In NVAF patients at high ICH risk, our results show a 74% decrease in AIS risk (actual 1.76%/year vs expected 6.8%/year based on CHA 2 DS 2 -VASc). Despite the very high ICH risk population studied including at least 48 CAA patients, only one patient had a recurrent IPH after LAAC. LAAC should be considered in NVAF patients at high ICH risk and studied in RCTs in this cohort.