• Patent Ductus Arteriosus 
    • Spectral Doppler interrogation of the abdominal aorta revealing holodiastolic flow reversal in a patient with a large PDA (represented by the arrows)
    • Secondary to diastolic runoff into the PDA in diastole

The subcostal view can be useful to assess hemodynamic impact of PDA. A moderate or large PDA may cause holodiastolic flow reversal in the abdominal aorta.