A case of anomalous origin of the right coronary artery from the pulmonary trunk: imaging of abnormal flow by Doppler color flow mapping

An asymptomatic 48-year-old woman was admitted to our hospital for evaluation of a precordial continuous murmur. The chest radiograph showed a normal cardiac silhouette. The resting electrocardiogram showed incomplete right bundle branch block. A multistage, graded treadmill exercise test did not affect the ST-T segment. A thallium-201 myocardial perfusion scan with a multistage ergometer exercise test showed no distinct perfusion defect. A two-dimensional echocardiogram disclosed a dilated left coronary artery arising from the left sinus of Valsalva, and a dilated right coronary artery crossing the aorta anteriorly to the pulmonary trunk. Real-time two-dimensional Doppler echocardiography of the same region showed an abnormal jet coming from the right coronary artery into the pulmonary trunk during diastole. A continuous wave Doppler flow study in the pulmonary trunk revealed a high-speed, disturbed flow which began in mid-systole, and continued during diastole. These findings were compatible with anomalous origin of the right coronary artery from the pulmonary trunk. An aortogram confirmed the diagnosis.