BackgroundThe left atrial appendage (LAA) is the main source of thromboembolism in patients with non-valvular atrial fibrillation. Unique LAA morphologies have been associated with the risk of thromboembolism. This study investigates the LAA anatomy in the Egyptian population using cardiac multi-detector computed tomography (MDCT).ResultsWe included 252 consecutive patients presenting for coronary computed tomography angiography in 2 tertiary centers in Egypt in the period from January to July 2017. Patients with atrial fibrillation, valvular affection, or left ventricular dysfunction were excluded. Two and three-dimensional cardiac MDCT images were assessed for LAA morphology, volume, length, and orifice position. The distribution of LAA morphologies was windsock (32.5%), chicken wing (25.4%), cauliflower (22.6%), and cactus (19.4%). Differences in the LAA dimensions in the 4 morphological variants were described. Females were less likely to have a chicken wing LAA morphology compared to males (7.9% vs 34.7%, p value < 0.01), and had a larger LAA volume, smaller LAA length, and a higher prevalence of high LAA orifice position.ConclusionsThe most common LAA morphology in our study population is windsock, which may represent the Egyptian population or patients in sinus rhythm. Females were less likely to have a chicken wing LAA morphology, and had a larger LAA volume, smaller length, and higher incidence of high orifice position. Clinical correlation into the translation of these differences into thromboembolic risk is required.