Evidence of patent ductus arteriosus and right-to-left shunt by finger pulse oxymetry and Doppler signals of agitated saline in abdominal aorta

The diagnosis of patent ductus arteriosus (PDA) with right-to-left shunt in the adult by using transthoracic echocardiography (TTE) is difficult because of limited windows. We report a case of a 23-year-old woman who was referred for treatment of primary pulmonary hypertension but was found to have a PDA with a right-to-left shunt. On examination she had asymmetric hypoxia of the upper extremities on finger pulse oxymetry. Transthoracic echocardiography revealed a large right atrium and no atrial or ventricular septal wall defects. The diagnosis of PDA with Eisenmenger's syndrome was made after evidence of a right-to-left shunt was confirmed by Doppler signals of intravenous agitated saline in the abdominal aorta. This case illustrates the utility of Doppler signals from agitated saline in the abdominal aorta and finger pulse oxymetry, in addition to physical examination, in the diagnosis of PDA with right-to-left shunt.