Right ventricular echocardiographic indices predict poor outcomes in infants with persistent pulmonary hypertension of the newborn.

AIMS: Infants with persistent pulmonary hypertension of the newborn (PPHN) have elevated pulmonary vascular resistance that can lead to right ventricular (RV) failure and death. Clinicians must decide which infants will fail conventional therapy and require transfer to extra corporeal membrane oxygenation (ECMO) centres, but accurate echocardiographic predictors have not been identified. We assessed echocardiographic measurements of RV pressure and function in predicting progression to death or ECMO in infants with PPHN.

METHODS AND RESULTS: Echocardiograms for infants ≥35-week gestation with a clinical diagnosis of PPHN were retrospectively reviewed. Traditional and strain echocardiographic measures were compared for those with or without the primary outcome of ECMO/cardiovascular death. Receiver operator curves identified cut points for measures that were significantly different. Of the 86 subjects analysed, 25 (29%) of the patients had the primary outcome of ECMO/death. The ECMO/death group had diminished tricuspid annular plane systolic excursion (TAPSE; P = 0.002) and RV global longitudinal peak strain (GLPS; P = 0.03), a predominant right-to-left shunt across the patent ductus arteriosus (PDA; P = 0.05), and an elevated oxygenation index (OI; P < 0.001). Sensitivity/specificity for TAPSE <4 mm was 56 and 85%, and for GLPS greater than or equal to -9% was 52 and 77%.

CONCLUSION: TAPSE, GLPS, and right-to-left PDA shunting were associated with progression to death/ECMO. RV free wall strain was not associated with the outcome, suggesting that diminished global strain better reflects clinical outcomes in this group. These thresholds may assist in the decision-making to transfer high-risk infants to ECMO centres.