Introduction
The COVID 19 pandemic has significantly affected health care delivery across cardiac specialties, including cardiac electrophysiology (EP). Infection prevention efforts mandate reallocation of resources with the postponement of the elective procedures and minimization of invasive pre-procedural investigations1. Catheter ablation of atrial fibrillation (AF) is a commonly performed procedure in the EP lab and carries a risk of peri-procedural thromboembolic cerebrovascular events (CVEs)2. Left atrial appendage (LAA) thrombus is the most common source of embolism in such patients. To minimize the peri-procedural risk of CVEs, current guidelines recommend at least 3 weeks of effective anticoagulation or pre-procedural transesophageal echocardiographic (TEE) evaluation of LAA for patients who present for their ablation procedure in AF2. TEE is variably employed in other populations of patients undergoing AF ablation based on their stroke risk profile and physician preferences. Previous studies have suggested the utility of pre-procedural cardiac computed tomography (CT) in place of TEE for evaluation of LAA thrombus3-9. In the current study, we describe our institutional experience of transitioning from pre-procedural TEE to cardiac CT for evaluation of LAA thrombus during the COVID-19 pandemic (part of an effort to reduce COVID transmission risks to healthcare providers), and the risk of peri-procedural CVEs among patients undergoing pulmonary vein isolation (PVI) with minimally interrupted peri-procedural anticoagulation before and after this practice change.