Biomarker screening for pulmonary hypertension in VLBW infants at risk for bronchopulmonary dysplasia

Background: Very low birth weight (VLBW) infants demonstrate altered alveolar and pulmonary vascular development and carry an increased risk of developing bronchopulmonary dysplasia (BPD) and pulmonary hypertension (PH). Risk stratification for BPD-associated PH (BPD-PH) in at-risk infants may help tailor management, improve outcomes, and optimize resource utilization. Methods: VLBW infants were screened for PH with blood gas measurements, serum NT-proBNP and bicarbonate (HCO3) levels, and echocardiograms if they remained on respiratory support at 34 weeks corrected gestational age. We then tested 11 models using different cutoffs for NT-proBNP and HCO3 to predict infants at low risk of BPD-PH. Results: We identified PH in 34 of 192 (17.6%) VLBW infants. The median NT-proBNP in VLBWs with PH was 2769 pg/mL versus 917 pg/mL in those without PH (p < 0.0001). A model with NT-proBNP < 950 pg/mL and HCO3 < 32 mmol/L had a sensitivity of 100%, specificity of 34.2%, and negative predictive value of 100%. Using this model, 54 of 192 (28%) of the patients in this study would have been categorized as low risk for PH and could have avoided a screening echocardiogram. Conclusion: NT-proBNP and HCO3 together may serve as sensitive and cost-effective screening tools for BPD-PH in VLBW infants.