Coronary artery obstruction due to membranous ridge of the right sinus valsalva associated with Tetralogy of Fallot: syncope mimics anoxic spell.

We report an infant with Tetralogy of Fallot who had suffered from repetitive attacks of syncope without obvious cyanosis. Careful observation by means of echocardiography and angiography revealed that the attacks resulted from acute coronary artery obstruction due to membranous ridge covering the sinus Valsalva. Surgical resection of the abnormal ridge and repair of Tetralogy of Fallot successfully improved the patient's symptoms. Syncope in children should be extensively investigated to exclude obstruction of the coronary arteries.