Evaluation of coronary artery anatomical variations and anomalies using 256 slice dual energy CT

Objective: To determine and classify the prevalence of coronary artery variations and anomalies using 256 dual energy computed tomography and to compare with previous studies. Materials and Methods: Data of 1600 consecutive patients who applied to Dicle University Faculty of Medicine Hospital between 03.01.2023 and 04.05.2024 and underwent coronary CT angiography on 256 dual-energy computed tomography (CT) devices with retrospective ECG triggering equipped with reconstruction software were evaluated retrospectively. Findings: Of the 1600 patients included in the study, 85.7% were right dominant, 9.2% were left dominant and 5.1% were codominant. While the conus artery originated from the proximal RCA in 67.8%, it originated from the ostial RCA in 26.2%, from the aorta in 4.5%. The conus artery branch could not be evaluated in 1.5%. Sinoatrial nodal artery (SANa) originated from the RCA in 68%, the LCX in 23.6%, the ostial RCA in 0.68%, the RSV in 0.25%, the LMCA in 0.06% and the 1st diagonal branch in 0.06%, while there was a SANa duplication originating separately from the RCA and LCX in 1.12%. SANa could not be detected in 6.2%. Ramus intermedius was detected in 24.7% of the patients. Myocardial bridging was detected in 22.7% of the cases and the most frequently affected artery was determined to be LAD. RCA in the Stephend's crook configuration was detected in 6.1% of the cases; while acute angulation variation of LCX was detected in 0.56%. Coronary artery anomalies (CAA) were detected in 3.18% of our patient population. The most common anomaly was determined as origin anomaly with a rate of 1.81%. The most frequently affected artery in origin anomalies was determined as RCA. SCA originating from RSV was found in 2 patients (0.12%). Interarterial course was detected in 10 patients (0.62%). High-output RCA was present in 4 patients (0.25%). Duplication anomaly was observed in 6 patients (%0.37), while the affected arteries were LAD in 5 patients and RCA in 1 patient. LMCA absence anomaly was detected 8 in 7 patients (%0.43). Ending anomaly was detected in 5 patients (%0.31), 4 of these patients had coronary artery fistula, and 1 had a complex formation with systemic ending and coronary artery fistula. Ectasia-aneurysm was observed in the coronary arteries in 2.44% of the cases. Conclusion: Our study revealed a wide distribution of coronary artery variations and anomalies in our region, with a prevalence of CAA of 3.18%, which is higher than many studies in the literature. Comparison of the findings with the literature revealed that some data overlapped but most of the data differed, indicating the presence of regional variations. In addition, the fact that MDCT detects CAAs more sensitively and in detail thanks to advanced imaging techniques has made this method a superior diagnostic tool compared to CCA. Keywords: Coronary artery, anomaly, variation, computed tomography