ORIGINAL ARTICLE PURPOSEWe aimed to evaluate the frequency and features of dual left anterior descending artery (LAD) variants using computed tomography (CT) angiography. METHODSA total of 1337 consecutive coronary CT angiography examinations performed between April 2010 and December 2013 were retrospectively evaluated for the presence of dual LAD. CT examinations were performed with either 64-or 320-row multidetector CT scanners. All CT angiography images were evaluated for the presence and morphologic features of dual LAD subtypes. RESULTSFifty-six dual LAD variations (4%) were identified in this study population. Type 1 was the most common type of dual LAD (n=48), while Type 3 (n=3) and Type 4 (n=2) were infrequent and Type 2 was not detected. Additionally, we detected previously unclassified dual LAD variations in three cases. CONCLUSIONDual LAD may be a relatively more common variant than described in the medical literature, which is mostly based on catheter angiography studies. Coronary CT angiography seems markedly efficacious for detecting and documenting the anatomical details of dual LAD subtypes, as well as showing other associated cardiocoronary anomalies. Dual left anterior descending (LAD) coronary artery is a rare congenital anomaly (1), basically defined as the existence of two distinct segments of the vessel occupying the anterior interventricular sulcus (AIS) of the heart.First study classifying dual LAD anomalies based on coronary catheter angiography was published in 1983 by Spindola-Franco et al. (2), which has served as a primary classification system. However, individual reports further described previously unclassified LAD variants (3, 4). Most of the recent publications about dual LAD anomalies involve case reports and there is a paucity of large series using coronary computed tomography (CT) angiography (3-8).At present, quite a large number of coronary CT angiography examinations are being performed and recognition of dual LAD variations by CT angiography requires familiarity. Being aware of dual LAD anomalies could be critical for coronary bypass surgery and interventions. Surely, sound knowledge on dual LAD anomalies is a prerequisite for proper management of patients with coronary artery disease.In this study, we aimed to identify the frequency of dual LAD variations, and define the morphoanatomical features based on Spindola-Franco classification, using CT angiography. Appendageal subtypes of this variation were also documented and discussed. Methods PatientsThe study was approved by our institutional review board. A total of 1337 consecutive coronary CT angiography examinations performed in our department from April 2010 to December 2013 were retrospectively evaluated for dual LAD anomalies. These examinations had been performed for various reasons including, but not limited to, the assessment of coronary and cardiac morphology, electrocardiography (ECG) abnormalities, coronary bypass graft evaluation, coronary stent evaluation, coronary atherosclerosis evaluation and screening fo...