LAUSR

Bronchopulmonary dysplasia (BPD) is a severe respiratory disease that affects premature neonatal lungs requiring the use of a ventilator or oxygen therapy for respiratory support. One of the most evident characteristics of BPD is the development of abnormal pulmonary vasculature characterized by dysmorphic, thickened with persistent anastomotic channels associate to abnormal vasoreactivity leading to a chronic lung vascular disease. In this issue Reference 3 reported their experience in a large cohort of premature newborns delivered <29 weeks of gestation characterized by a 60% prevalence of BPD. The major findings of this study was the possibility of predicting BPD by analyzing the pulmonary artery waveforms with an high accuracy. Indeed the ratio between the time to peak velocity (TPV) and the right ventricular ejection time (RVET) assessed during the first 3 weeks of life showed an area under the curve of 0.811 of developing later in life with an odds ratio of 19.9 when TPV/RVET values were above 0.34. Further Authors reported an interobserver agreement of 92.75% of this ratio thus suggesting a potential clinical use. Early identification of subjects who will develop BPD is of clinical interest since it may open a window of opportunity for treatment intervention finalized to prevent or modify the natural history of the disease. The next step will be to extend these diagnostic tools to prenatal life focusing on fetuses at higher risk of early delivery such those complicated by fetal growth restriction or premature rupture of membranes (PROM). High-resolution color doppler ultrasound allows a comprehensive evaluation of the fetal lung circulatory system allowing to record spectral Doppler velocity waveforms from the main stems of the pulmonary artery to the most peripheral vessels (Figure 1). Moreover, there are evidences that abnormal velocity waveforms from peripheral pulmonary vessels are associated with the development of lung hypoplasia in pregnancies complicated by early PROM. We guess that the study of lung circulation starting already during prenatal life will help in decision making on the timing of delivery in pregnancies at higher risk of preterm delivery, enhance communication and counseling of partners regarding the implications and prognosis of their infants, and stratifying newborns for the enrollment in clinical trials.