Addition of Subdiaphragmatic Vessels in Evaluation of Hemodynamically Significant Patent Ductus Arteriosus in Premature Infants

Although there are various echocardiographic measurements that can determine the hemodynamic significance of a patent ductus arteriosus (PDA), there are few quantifiable measures to determine if there is a vascular steal secondary to a large PDA from the abdominal organs. If the PDA is as large as the branch pulmonary arteries, then effectively one-third of the blood that should go to the abdomen is pushed back toward the lungs. This suggests a vascular steal from the abdomen, causing potential ischemia to the bowel and kidneys. Our original research resulted in a diagnostic marker (PDAM) to assist clinicians with the management of PDAs. The superior mesenteric artery and renal artery spectral Doppler waveforms were added to the PDAM score to evaluate perfusion in infants with PDA. The absence of diastolic flow or staccato flow, in which there is a loss of end-systolic flow, is prognostic of a vascular steal phenomenon.