The pi sign as an indicator of aberrant origin of obtuse marginal coronary artery.

Of 3,856 coronary angiographic studies performed by a single operator from December 2000 to March 2006, 24 (0.6%) had an aberrant origin of the obtuse marginal branch from the left anterior descending coronary artery (n = 20, 84%) or its diagonal branch (n = 2, 8%) or from the ramus intermedius coronary artery (n = 2, 8%) with an appearance mimicking the Greek letter pi. Patients were 40 to 69 years old (54 +/- 9), all were white, and 18 (75%) were men. Obstructive coronary artery disease was present in 13 (54%) and involved the aberrant obtuse marginal branch in 4 (17%). No specific pattern of symptoms, clinical presentation, or electrocardiographic finding could be attributed directly to this coronary anomaly. In conclusion, we have described a previously unreported coronary anomaly. Potential implications of this type coronary anomaly are (1) an angiographic appearance of a missing branch of the left circumflex coronary artery and (2) extensive anteroseptal, apical, and posterolateral ischemia due to proximal left anterior descending coronary artery obstruction.