Clinical and Echocardiographic Characteristics of Left Atrial Diverticulum

BACKGROUND: Remarkable advancements in cardiac computed tomography (cCT) have provided new insights into previously undescribed anatomical structures, such as the left atrial diverticula (LADs). The aims of the present study were to assess the characteristics of LADs and their relationship with cardiac function. METHODS: We analyzed consecutive patients who underwent preprocedural cCT and transthoracic echocardiography (TTE) for catheter ablation of paroxysmal or persistent atrial fibrillation between January 2020 and 2022. LADs were identified on cCT as smooth contoured protrusions extending from the left atrial wall. LADs were classified as cystiform (body length/orifice width ratio <2) or tubiform (body length/orifice width ratio ≥2), and their volume was measured. RESULTS: Among 201 patients (mean age: 65 ± 12 years, 66% male), 124 LADs were detected in 105 patients, with 19 patients having two LADs each. Of these, 99 (80%) were classified as cystiform, and 25 (20%) as tubiform. No statistically significant differences were observed in the clinical and echocardiographic characteristics between patients with and without LADs. Log-transformed volume of tubiform LADs showed a moderate correlation with age (R = 0.62; p = 0.001), and mild correlations with LA volume index (R = 0.40; p = 0.05), and E/e' (R = 0.44; p = 0.027). However, no such associations were observed for cystiform LADs. CONCLUSIONS: LADs were present in approximately half of the patients, with no significant association between LADs prevalence and clinical or echocardiographic characteristics. However, the relationship between LAD volume and cardiac function varied depending on the LAD subtypes.