Pulmonary Hypertension in the Preterm Infant with Chronic Lung Disease can be Caused by Pulmonary Vein Stenosis: A Must-Know Entity.

Pulmonary hypertension (PHT) in the preterm infant is frequently due to chronic lung disease. Rarely, PHT can be caused by pulmonary vein (PV) stenosis that has been described to be associated with prematurity. This study is a retrospective analysis of all premature infants <37 weeks of gestation with PV stenosis and PHT in two French pediatric congenital cardiac centers from 1998 till 2015. Diagnosis, hemodynamics and outcome are described. Sixteen patients met the inclusion criteria. Median gestational age was 28 weeks (25 + 6-35) with a median birth weight of 842 g (585-1500). The majority of infants (87.5 %) had chronic lung disease and associated cardiac defects. Median age at diagnosis was 6.6 months (1.5-71). Fifty-six percentage (n = 9) had initially unilateral PV stenosis affecting in 89 % the left PV. Median initial invasive mean pulmonary artery pressure was 42 mmHg (25-70). Treatment options included surgical intervention (n = 6), interventional cardiac catheter (n = 3) and/or targeted therapy for pulmonary arterial hypertension (n = 5). In six patients, decision of nonintervention was taken. Global mortality was 44 %. All deaths occurred within 7 months after diagnosis regardless of chosen treatment option. Mean follow-up was 6 years (4.9 months-12 years). At last visit, all eight survivors were in stable clinical condition with five of them receiving targeted therapy for pulmonary arterial hypertension. PV stenosis is an unusual cause of PHT in the premature infant with chronic lung disease. Diagnosis is challenging since initial echocardiography can be normal and the disease is progressive. Treatment options are numerous, but prognosis remains guarded.