title: A new look at bronchopulmonary dysplasia: postcapillary pathophysiology and cardiac dysfunction.
abstract: Pulmonary hypertension (PH) and right ventricular function are the focus of cardiovascular effects of bronchopulmonary dysplasia (BPD). We assessed cardiac indexes reflecting systemic afterload and pulmonary venous back pressure as pathophysiologic factors. Cardiac parameters were measured by conventional echocardiography in 20 preterm infants with severe BPD and compared with those of 10 preterm infants with no BPD and 20 healthy term infants. In infants with severe BPD, PH was noted in 5 (25%) by tricuspid regurgitation Doppler jet ≥2.8 m/s and in 15 (75%) by time to peak velocity/right ventricular ejection time <0.34. Among systemic cardiac indexes, significant impairment of diastolic measures was noted in the BPD group compared with infants with no BPD and term infants. The significance persisted after adjusting for gestational age and birth weight. These included transmitral E/A ratio (1.07 ± 0.07 vs. 0.91 ± 0.04 vs. 0.89 ± 0.09;P< 0.0001), isovolumic relaxation time (68.8 ± 3.9 vs. 58.5 ± 7.8 vs. 54.2 ± 5.7 ms ;P< 0.0001), mitral valve stroke volume (4.7 ± 0.7 vs. 5.6 ± 0.6 vs. 5.9 ± 0.1;P= 0.002), and myocardial performance index (0.33 ± 0.05 vs. 0.28 ± 0.01 vs. 0.27 ± 0.05;P= 0.03). Left ventricular output was significantly lower in the BPD cohort (183 ± 45 vs. 189 ± 9 vs. 191 ± 32 mL/kg/min;P= 0.03). Altered systemic (left-sided) cardiac function was noted in infants with BPD, which may lead to pulmonary venous congestion contributing to a continued need for respiratory support.
authors.affiliation: Monash Newborn, Monash Children's Hospital, Monash Health, Melbourne, Australia; Department of Paediatrics, Monash University, Melbourne, Australia.
authors.forename: Arvind
authors.initials: A
authors.lastname: Sehgal
authors.affiliation: Monash Newborn, Monash Children's Hospital, Monash Health, Melbourne, Australia.
authors.forename: Andra
authors.initials: A
authors.lastname: Malikiwi
authors.affiliation: Monash Centre for Health Research and Implementation, School of Public Health and Preventive Medicine, Monash University, Melbourne, Australia; and Clinical Haematology Department, Alfred Hospital, Melbourne, Australia.
authors.forename: Eldho
authors.initials: E
authors.lastname: Paul
authors.affiliation: Monash Newborn, Monash Children's Hospital, Monash Health, Melbourne, Australia; Department of Paediatrics, Monash University, Melbourne, Australia.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Tan
authors.affiliation: Department of Paediatrics, Monash University, Melbourne, Australia; Paediatric and Foetal Cardiac Units, Monash Medical Centre, Monash Health, Melbourne, Australia.
authors.forename: Samuel
authors.initials: S
authors.lastname: Menahem
keywords: cardiac function; chronic lung disease; infants; pulmonary hypertension