Pulsed wave Doppler interrogation in a patient with patent ductus arteriosus and significant left-to-right shunting with continuous diastolic run off

In a patient with a patent ductus arteriosus (PDA) and significant left-to-right shunting, pulsed Doppler echocardiography shows flow in the descending aorta proximal to the PDA. Note the continuous diastolic run off pattern of flow toward the ductus (arrows).