Coronary artery anomalies are often observed on angiography. Their incidence ranges from 0.6% to 1.3% in various case series [1, 3]. Most of these anomalies are benign and do not necessitate any form of intervention .
Dual LAD is a rare coronary anomaly. Spindola-Franco et al. first described and classified dual LAD into four types . With newer anomalies being reported it was reclassified into six types by Lee et al. [6, 7]. The classification is based on the origin and course of the short and long LAD and gives details with regards to the origin of the septal perforators and diagonals. Types IV, V, and VI have one of the LADs arising from the right coronary circulation.
Identifying the presence of these anomalous arteries is integral in the planning for myocardial revascularization. Type IV variant of dual LAD is very rare and can be missed on angiography [8, 9]. As the short LAD may give rise to the diagonals and septals the long LAD may be mistaken for an aberrant vessel/collateral. If both the short and long LADs are severely stenosed, grafts to both the vessels may be needed because the major supply to the septum and the anterior ventricular wall may come from both the vessels.
It is important that surgeons have a clear perspective about the origin and course of the LAD when these anomalies are observed. This will ensure that the surgeon avoids an incorrectly placed arteriotomy and that no territory is left without revascularization . It is also emphasized that when there is a disparity between the angiographic anatomy and the coronary course seen intra-operatively, the angiogram should be reviewed again and a second perspective should be sought.
Careful review of the angiogram prior to surgery helped us to identify this coronary anomaly. The long LAD was visualized running an abnormal course and found lying in the mid to distal anterior interventricular groove. The short LAD was seen running lateral to the groove almost mimicking the course of a diagonal artery. Both the LADs were grafted separately and the myocardial revascularization was complete.
Rights and permissions
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.