Identifying Abnormal Ostial Morphology in Anomalous Aortic Origin of a Coronary Artery.

Background: Anomalous origin of a coronary artery from the contralateral sinus of Valsalva is associated with exercise-induced ischemia and sudden death. That is thought to be due to aortic enlargement in patients with an elliptical ostium. We hypothesize that virtual angioscopy can identify abnormal coronary ostial morphology in these patients.

Methods: We retrospectively analyzed 55 consecutive pediatric coronary artery magnetic resonance imaging studies from January 2006 to January 2010 with the diagnosis of anomalous right (n = 20), or left (n = 7) coronary artery, or normal coronary origins (n = 28). One postmortem heart specimen with anomalous left coronary artery was imaged and analyzed to validate our technique. Virtual angioscopy analysis was used for visualization and measurement of the coronary ostia.

Results: Distinct aortic origins of the right and left coronaries were seen in all 55 studies. An elliptical orifice with a longer superior-inferior dimension was seen in all anomalous ostia, in contrast to a circular ostium in all normal origins. That was quantified in anomalous ostia with a long-axis to short-axis ratio of 2.5 ± 0.5 (right) and 2.4 ± 0.5 (left) compared with 1.1 ± 0.2 (right) and 1.0 ± 0.3 (left) in controls (p < 0.001 for right and left ostia comparisons). Ostial morphology was confirmed in all 9 patients who underwent operative repair and in 1 patient at autopsy.

Conclusions: Virtual angioscopy identifies abnormal ostial morphology in anomalous coronary artery patients, which is important for characterizing the diagnosis of patients who may be at risk for sudden death.