Congenital aortocaval fistula mimicking atrial septal defect on transthoracic echocardiography

An 18-year-old woman was admitted to our clinic for advanced cardiac evaluation due to long-standing exercise induced dyspnea. Physical examination of the patient showed absence of pallor, clubbing, cyanosis or any manifestations of Marfan syndrome. All peripheral pulses were symmetrically palpable. No jugular distention was seen. Cardiac auscultation revealed a continuous murmur best heard at the third right intercostal space. Pulmonary auscultation was normal. Electrocardiography revealed a sinus rhythm without trace abnormalities. Chest X-ray was noncontributory. Laboratory tests were normal. Transthoracic color-flow Doppler echocardiography revealed an uncertain colored flow through the interatrial septum mimicking atrial septal defect or patent foramen ovale (Figure 1 A). The right atrium and right ventricle were not dilated, and paradoxical motion of the ventric-ular septum was not present. Two-dimensional imaging from the subcostal position best revealed no defect in the atrial septum. Complete echocardiographic examination identified normality of the coronary sinus, normal entrance of the pulmonary veins, an intact primum portion of the atrial septum, and normal mitral valve function. Mid-esophageal views of transesophageal echocar-diography demonstrated an abnormal double bubble-like structure with a tunnel in close relationship with the aor-ta and right heart chambers (Figure 1 B). Agitated saline contrast echocardiography revealed no passage between left and right heart sides. Coronary computed tomog-raphy angiography showed a fistulous communication between the ascending aorta and superior vena cava (SVC) (Figure 1 C). Cardiac catheterization revealed a fis-tula with a proximal end close to the left main coronary artery ostium but with separated origins (Figure 1 D). Percutaneous closure by means of coil embolization was decided. By means of catheterization, and following can-nulation of the proximal end of the fistula by an Amplatz catheter, two coils were successfully inserted. There were no complications regarding the intervention. The patient was discharged with medical therapy for regular out-patient follow-up. At the 6-month visit the patient did not have any cardiac complaints and transthoracic echocar-diography was normal. Communications between the aortic root or coronary arteries and right heart structures include ruptured sinus of Valsalva, coronary arterial fistula, congenital tunnel to the right ventricle or right atrium, aortocaval fistu-la, rupture of a dissecting aneurysm of the ascending aorta [1], and pseudoaneurysm of the right coronary artery followed by formation of a fistula between the aneurysm and right atrium. Aneurysmal aorto-right atri-al communication represents another potential cause of left-to-right shunt [2, 3]. Aortocaval fistula is a rare cause of left-to-right shunt. Common causes …