Study design and patient population.
The study procedures were reviewed and approved by the Institutional Research Board (IRB) of Medical College of Wisconsin. In this single-center retrospective study, AF patients with LAA thrombus were identified through a query of ICD-10 codes within the electronic medical record system. This search identified patients with the diagnosis of non-valvular atrial fibrillation (NVAF), a TEE study performed between February 1, 2014, and December 31, 2020, and a diagnosis of intracardiac thrombus. In this manner 216 subjects were identified. Two study cardiologists (MB and AW) manually reviewed the TEE images and medical records for these subjects. Subjects with intracardiac thrombus not contained within the LAA or thrombus unconfirmed by the two study reviewers, and those for whom imaging did not permit orthogonal measurements of the left atrial appendage ostial diameters were excluded from the study. A total of 79 patients constituted the final thrombus cohort (Figure 1).