A new variation in coronary artery anatomy: type VII dual left anterior descending artery

Nowy wariant anatomii tętnic wieńcowych: podwójna lewa tętnica zstępująca przednia typu VII

Muzaffer Saglam1, Ersin Ozturk1, Kemal Kara1, Ejder Kardesoglu2, Hakan Mutlu1

1Department of Radiology, GATA Haydarpasa Training Hospital, Uskudar, Istanbul, Turkey
2Department of Cardiology, GATA Haydarpasa Training Hospital, Uskudar, Istanbul, Turkey

Address for correspondence:
Muzaffer Saglam, MD, GATA Haydarpasa Training Hospital, Uskudar, Istanbul, 34668, Turkey, tel: 0090 545 6755055, fax: 0090 216 542 2021,
e-mail: mzsaglam@yahoo.com

A 53-year-old man presented with chest pain. Laboratory and electrocardiography findings were normal. Echocardiography showed a normokinetic wall motion with left ventricular ejection fraction at 60%. Coronary computed tomography angiography identified no evidence of atherosclerosis and stenosis. However, an aberrant long left anterior descending (LAD) artery originating from the right coronary sinus and a short LAD originating from the left main coronary artery (LMCA) were observed. After running from the right coronary sinus, the long LAD segment coursed intramyocardially within the septal crest and entered the anterior interventricular groove (AIVG) below the termination point of the short LAD. The short LAD terminated high in the AIVG after originating from the LMCA (Fig. 1A, B). The septal perforators originated from both short and long LAD, and the diagonal branches originated from the short LAD (Fig. 2A, B). Dual LAD is a rare anomaly and has been categorised into 6 subtypes based on the origin, course, and termination of the short and long LAD (Table 1) [Maroney J, Klein LW. Catheter Cardiovasc Interv, 2012; 80: 626–629]. Because of its influence on surgical or angiographic intervention strategies, recognition of this anomaly is important. In dual LAD, there are a short and a long LAD segments within the AIVG. The short LAD typically arises from the LMCA and terminates high in the AIVG. The long LAD may have a more variable origin, course around the short segment, and return to the AIVG distally [Spindola Franco H et al. Am Heart J, 1983; 105: 445–455; Agarwal PP, Kazerooni EA. Am J Roentgenol, 2008; 191: 1698–1701]. We present a novel type of dual LAD — type VII — which does not fit within the traditional classification system.

Figure 1. Volume-rendered (A) and coronary tree (B) images demonstrate the proximal take off of the long LAD and its distal course within the AIVG (long arrow). The short LAD terminates within the proximal AIVG (short arrow). A dominant diagonal branch of the short LAD coursing to the lateral wall of the left ventricle can also be seen (curved arrow).

Figure 2. Axial thick-slab (A) and curved planar-reformatted (B) images of the long LAD reveal its origin (arrow) from the right coronary sinus. The proximal intramyocardial course of the long LAD (curved arrow) and a septal perforator (arrowhead) are well depicted

Table 1. Classification of dual left anterior descending artery

Conflict of interest: none declared