Oxygen supplementation is helpful for the echocardiographic detection of anomalous left coronary artery from the pulmonary artery

Background: The echocardiographic diagnosis of anomalous left coronary artery from the pulmonary artery (ALCAPA) can be challenging. The aim of this study was to assess the hypothesis that diagnosis can be enhanced by using supplemental oxygen, which decreases pulmonary vascular resistance and increases retrograde flow from the coronary artery into the pulmonary artery. Methods: Demographic, echocardiographic, and cardiac catheterization data were reviewed in patients presenting with ALCAPA from 1999 to 2007. Results: Twenty-one patients (seven male; median age, 5 months) presented with ALCAPA. Nine underwent imaging with oxygen. Two of these nine (22%) had previous standard echocardiographic studies that missed the diagnosis. Cardiac catheterization was required for diagnosis of ALCAPA in 42% of patients who underwent standard echocardiography compared with 11% of patients who received supplemental oxygen in addition to standard echocardiography. The administration of oxygen caused no significant change in heart rate or cardiorespiratory support. Conclusion: Transient oxygen administration is useful in the noninvasive diagnosis of ALCAPA.