An Echocardiographic Screening Program Helps to Identify Pulmonary Hypertension in Extremely Low Birthweight Infants with and without Bronchopulmonary Dysplasia: A Single-Center Experience

Abstract

Background: Pulmonary hypertension (PH) affects 1 in 6 infants with a birthweight <1,000 g (extremely low birthweight; ELBW) and is frequently associated with bronchopulmonary dysplasia (BPD). If untreated, the mortality rates of the disease are high. Objectives: The aim of this study was to characterize risk factors for PH in ELBW infants and to describe the timing of onset of the disease by setting up a screening program. Methods: ELBW infants treated at the Department of Neonatology (level III neonatal intensive care unit at the University of Cologne Medical Centre, Germany) between January 2010 and March 2015 were included. Echocardiography screening for PH was performed either before discharge or if BPD was diagnosed. Additionally, infants had at least 1 echocardiographic scan after discharge. Survival with PH, age at diagnosis of PH, and risk factors associated with PH were assessed. Results: In total, 34/188 (18%) infants had PH. Of these, 14 (41%) were identified after discharge. Another 11 (32%) were diagnosed with PH without suffering from moderate or severe BPD. The risk factors for diagnosis of PH were moderate (odds ratio, OR 4 [2-8]) or severe BPD (OR 13 [2-71]), prolonged rupture of membranes >7 days (OR 5 [1-19]), and birthweight below the 3rd percentile (OR 3 [1-9]). All infants with PH before discharge and 50% diagnosed after discharge were treated with sildenafil (2.0 mg/kg/day). PH resolved and sildenafil was discontinued in all patients after a median duration of 13 months (IQR 8-20). Conclusions: An echocardiographic screening program may help to identify infants with PH. Examinations should include all ELBW infants irrespective of the presence of BPD and be continued after discharge.

Prospective study of pulmonary hypertension in preterm infants with bronchopulmonary dysplasia

“…The relationship between severity of BPD and PH has been variable in the literature. Few studies could not find an association with PH and severity of BPD . In contrast, Bhat et al reported PH in 24/26 cases (92%) with moderate to severe BPD .…”

“…The prevalence of PH at enrollment in our cohort (28.5%) is difficult to compare to “early” PH in prior studies as our cohort's first echocardiogram was completed after 28 days of life timed with initial diagnosis of BPD. In a cohort study of extremely low birth weight infants with BPD, screening echocardiogram detected PH in 18% infants with 10.6% diagnosed before discharge and 7.4% cases diagnosed at screening 3‐6 months after discharge . It is unclear whether these patients had other factors that contributed to the delayed onset of their pulmonary vascular disease.…”

Current understanding and perioperative management of pediatric pulmonary hypertension

“…BPD is the most common morbidity of children born <30 weeks’ gestation and remains the most common lung disease of infancy . BPD is diagnosed in roughly 40% of infants born ≤28 weeks gestational age, which results in 10 000‐15 000 new cases in the USA each year . While knowledge of the pathophysiology and pathobiology of BPD continues to evolve, BPD is defined as a chronic lung disease in preterm infants born ≤32 weeks’ gestation who require ongoing oxygen therapy at 36 weeks’ postconceptual age .…”

“…22 BPD is diagnosed in roughly 40% of infants born ≤28 weeks gestational age, which results in 10 000-15 000 new cases in the USA each year. [22][23][24][25][26] While knowledge of the pathophysiology and pathobiology of BPD continues to evolve, BPD is defined as a chronic lung disease in preterm infants born ≤32 weeks' gestation who require ongoing oxygen therapy at 36 weeks' postconceptual age. 23,27 The pathophysiology is characterized by a uniform arrest of lung development and dysmorphic pulmonary capillaries.…”

Should All Extremely Premature Infants Be Screened for Pulmonary Hypertension?

“…The study by Mehler et al [16] in this issue of Neonatology prospectively evaluated 360 ELBW preterm infants for echocardiographic signs of PH. Infants with BPD were evaluated at 36 weeks' PMA while those without BPD were studied shortly before discharge.…”