Table 1.

Summary of essential parameters used for echocardiographic assessment and hemodynamic evaluation of PDA in ELGAN infants.

PDA evaluation criteria	Essential echocardiographic parameters for assessment of PDA and hemodynamic evaluation
Ductal characteristics	• PDA size (small <1.5 mm, moderate 1.51–2 mm, large >2 mm) and flow direction (left to right, right to left, or bi-directional) and Doppler assessment with maximum velocity (Vmax) in systole and end-diastole
Assessment of pulmonary over-circulation	• Dilated left side of the heart on visual inspection “eyeballing” and LA/Ao ratio (mild <1.4, moderate 1.41–1.6, severe >1.6) OR LVEDD (correlate with z-scores) OR LPA diastolic velocity, mean velocity >0.42 m/s, end-diastolic velocity >0.2 m/s OR Reversal of mitral E/A ratio *Document presence or absence and magnitude of intra-atrial shunt
Assessment of systemic hypoperfusion	• Retrograde or absent blood flow during diastole in: -descending aorta OR -coeliac trunk or superior mesenteric artery (SMA) OR -anterior or middle cerebral artery

A comprehensive echocardiographic assessment should be performed to rule out any underlying congenital heart defect or pulmonary hypertension and delineate orientation of arch (left or right sidedness) before any intervention to close the PDA.