Type IV dual left anterior descending coronary artery: a case report

BACKGROUND: Dual left anterior descending (LAD) artery or duplication of LAD is a rarely reported coronary anomaly, consisting of two branches supplying the usual distribution of the LAD. Type IV dual LAD, in which a short LAD arises from the left main coronary artery and a long LAD arises from the right coronary artery is remarkably rare, and has not been reported in a Bangladeshi subject. CASE PRESENTATION: We describe the case of a 70-year old Bangladeshi male who presented with breathlessness in the background of a prior inferior myocardial infarction. Coronary angiography revealed an anomalous dual LAD. The short LAD which arose from the left main coronary artery gave off the first septal branch and terminated after giving off a large diagonal branch which continued further down towards the apex. The long LAD arose from the proximal right coronary artery and after traversing a distance, arrived at the interventricular septum, terminating at the apex after giving off diagonal branches. The right coronary artery was totally occluded from its early mid part and well-collateralized with retrograde flow from the left system. CONCLUSION: We describe a case with unique variation of dual LAD type IV, which has previously not been described in a Bangladeshi subject thus far. Coronary angiography is vital to determine this coronary anomaly, which is usually detected incidentally on routine angiography for chest pain, sometimes with involvement of significant lesion of other coronary arteries, as in this case.