To describe the prevalence of symptomatic and asymptomatic cerebrovascular disease in patients with nonvalvular atrial fibrillation (AF) prior to left atrial appendage (LAA) closure.

Presence of cerebral microbleeds (CMB) is associated with intracranial hemorrhage in patients with nonvalvular AF on oral anticoagulant (OAC). LAA closure is known to be an effective alternative to long-term OAC in patients with increased bleeding risk; however, the real-world prevalence of intracranial hemorrhage, CMB and ischemic stroke in patients with AF who underwent LAA closure is not well described.

Consecutive patients with AF who underwent LAA closure at the Mayo Clinic (MN, FL, and AZ) from 2010 to 2018 were included.  Demographic and comorbid conditions were abstracted. Presence of intracranial hemorrhage and ischemic stroke were ascertained from clinical notes and radiology reports. CMBs were identified on MRI brain; number and location of CMB were recorded. Prevalence of intracranial hemorrhage, and CMB and ischemic stroke were calculated.

Our cohort included 232 patients, 33% were women. Mean age was 76 ±7 yrs., 86% had hypertension, 33% had diabetes, 23% had congestive heart failure, 46% had coronary artery disease, and 29% had carotid stenosis. The prevalence of ischemic stroke was 40%, intracranial hemorrhage was 34% (intraparenchymal hemorrhage 17%, subdural hematoma 12%, and subarachnoid hemorrhage 8%). A total of 50.8% (118/232) patients had brain MRI before LAA closure.  Of those who had MRI, 46% had CMBs, 29% were deep CMBs, and 26% had lobar CMBs.

More than half of the patients in this real-world cohort of patients who underwent LAA closure across 3 academic centers had cerebrovascular disease. Prospective studies to further stratify risk by cerebrovascular findings for LAA closure in preventing stroke and intracranial hemorrhage are needed.