Prevalence and Characteristics of Coronary Artery Anomalies in an Adult Population Undergoing Multidetector-row Computed Tomography for the Evaluation of Coronary Artery Disease

Background: Congenital coronary anomalies are uncommon with an incidence ranging from 0.17 % in autopsy cases to 1.2 % in angiographically evaluated cases. The recent development of ECG-gated multi-detector row computed tomography (MDCT) coronary angiography allows accurate and noninvasive depiction of coronary artery anomalies.

Methods: This retrospective study included 2572 patients who underwent coronary 64-slice MDCT coronary angiography from January 2008 to March 2012. Coronary angiographic scans were obtained with injection of 80 ml nonionic contrast medium. Retrospective gating technique was used to synchronize data reconstruction with the ECG signal. Maximum intensity projection, multi-planar reformatted, and volume rendering images were derived from axial scans.

Results: Of the 2572 patients, sixty (2.33 %) were diagnosed with coronary artery anomalies (CAAs), with a mean age of 53.6 ± 11.8 years (range 29-80 years). High take-off of the RCA was seen in 16 patients (0.62 %), of the left main coronary artery (LMCA) in 2 patients (0.08 %) and both of them in 2 patients (0.08 %). Separate origin of the left anterior descending artery (LAD) and left circumflex artery (LCx) from left sinus of Valsalva (LSV) was found in 15 patients (an incidence of 0.58 %). In 9 patients (0.35 %) the right coronary artery (RCA) arose from the opposite sinus of Valsalva with a separate ostium. In 6 patients (0.23 %) an abnormal origin of LCX from the right sinus of Valsalva (RSV) was found with a further posterior course within the atrioventricular groove. A single coronary artery was seen in 3 patients (0.12 %). It originated from the right sinus of Valsalva in one patient and from LSV in two patients. In two other patients (0.08 %) the left coronary trunk originated from the RSV with separate ostium from the RCA. LCA originating from the pulmonary artery was found in one patient (0.04 %). A coronary artery fistula, which is a termination anomaly, was detected in 4 patients (0.15 %).

Discussion: Although these anomalies, which are remarkably different from the normal structure, exist as early as birth, they are incidentally encountered during selective angiography or at autopsy. The incidence in reported angiographic series ranges from 0.6 % to 1.3 %. Variations in the frequency of primary congenital coronary anomalies may possibly have a genetic background. The largest angiographic series of 126595 patients, by Yamanaka and Hobbs, reported a 1.3 % incidence of anomalous coronary artery.

Conclusion: The results of this study support the use MDCT coronary angiography as a safe and effective noninvasive imaging modality for defining CAAs in an appropriate clinical setting, providing detailed three-dimensional anatomic information that may be difficult to obtain with invasive angiography.