Background Enlargement of the LA is known to increase the risk of atrial fibrillation (AF) and its associated complications. However, the relation between other left atrial (LA) anatomical abnormalities and the risk of developing AF is less well described. Objective The aim of this study was to compare the prevalence of LA anatomical abnormalities between a group of patients with recurrent AF and a group of patients in sinus rhythm (SR) with the use of cardiac computed tomography (CT). Methods The cardiac CT prevalence, location, and size of LA accessory appendages and diverticula were assessed in 200 patients with recurrent AF referred for radiofrequency catheter ablation and compared with a control group of 200 patients in SR. Results The prevalence and mean length and width for diverticula were 23.5%, 8.1 mm, and 8.1 mm, in the AF group and 20.5%, 7.8 mm, and 7.2 mm in the SR group, respectively, and for accessory appendages 6.5%, 8 mm, and 6.3 mm in the AF group and 6.5%, 9.4 mm, and 5.7mm in the SR group, respectively. In both groups, the most common location for a diverticulum or an accessory appendage was the right anterosuperior LA wall. The prevalence, location, and size of accessory appendages and diverticula were not significantly different (P > 0.05) between cohorts. Conclusion This study found no difference in the prevalence and anatomic characteristics of LA accessory appendages and diverticula between patients in recurrent AF and patients in SR.