|Home | About | Journals | Submit | Contact Us | Français|
An elderly man presented after a collapse with inferior ST-segment elevation. Coronary angiography revealed ectatic left anterior descending (LAD) artery with an aberrant side branch originating from the mid-segment (figure 1A, B). There was slow flow in this vessel and the distal segment of vessel was not visualised. There was obstructive disease in the first obtuse marginal branch of the left circumflex (LCx) artery (figure 1C). Despite searching in all three coronary sinuses and performing an aortogram the right coronary artery (RCA) was unidentified.
He subsequently had CT coronary angiography (CTCA), which revealed that the branch originating from the mid-LAD was the RCA (figure 2A). He underwent repeat angiography, contrast was injected deep into the RCA using a microcatheter, which demonstrated a chronic total occlusion of the distal RCA (figure 2B, C). The disease in the LCx artery was felt to be the reason for his acute presentation and he had successful intervention with drug-eluting stents (figure 2D).
The anomalous origin of the RCA as a branch of the LAD artery is a very rare variation of single coronary artery. The incidence of coronary artery anomalies is 1.3%, RCA originating from the mid-LAD is one of the rarest anomalous coronary variation.1 2 Most coronary artery anomalies are incidentally found during coronary angiography, this is limited by difficult spatial orientation of X-ray. CTCA can be utilised to demonstrate origin and course of anomalous arteries. This case highlights the importance of recognition of anatomical variation, especially in acute presentations, and demonstrates the role of CTCA.
Competing interests: None declared.
Patient consent: Obtained.
Provenance and peer review: Not commissioned; externally peer reviewed.