Clinical impact of left atrial enlargement in Korean patients with atrial fibrillation.

We sought to evaluate the clinical implication of LAE based on left atrial anterior-posterior (LA AP) dimension or LA volume index (LAVI) in Korean patients with atrial fibrillation (AF). We enrolled 8159 AF patients from the CODE-AF registry. The primary outcome was rate of stroke or systemic embolism (SSE). The prevalence of mild, moderate, and severe LAE by LA AP dimension was 30.6%, 18.5%, and 21.4%, and by LAVI (available in 5808 patients) was 15.7%, 12.5% and 37.8%, respectively. Compared with no or mild LAE, patients with significant LAE (moderate to severe LAE, n = 3258, 39.9%) were associated with a higher rate of SSE (2.5% vs. 1.4%, P = 0.001). Multivariable analysis suggested presence of significant LAE by LA AP dimension was associated with a higher risk of SSE in the overall population (HR 1.57, 95% CI: 1.14-2.17, P = 0.005) and in patients using anticoagulants (n = 5836, HR 1.79, 95% CI: 1.23-2.63, P = 0.002). Patients with significant LAE by LAVI were also at higher risk of SSE (HR 1.58, 95% CI: 1.09-2.29, P = 0.017). In conclusion, significant LAE by LA dimension or LAVI was present in 39.9% and 50.2% of AF patients, respectively, and was associated with a higher rate of SSE.