Influence of extreme prematurity and bronchopulmonary dysplasia on cardiac function

Objective: Prematurity and bronchopulmonary dysplasia (BPD) are associated with poorly understood abnormalities of ventricular function. We therefore comprehensively compared biventricular function in infants with and without BPD. Methods: Prospective observational study in extremely preterm infants with (n = 20) and without (n = 38) BPD using conventional and advanced echocardiography at 28 days (T1) and near‐term (T2). Results: Infants with BPD had lower birth gestational age (26.7±1.9 vs 27.4±1.1 weeks, p = 0.047) and weight (884±207 vs 1108±190 g, p = 0.0001). BPD was associated with larger right ventricles (RV) and reduced RV systolic strain rate at T1 and pulmonary hypertensive indicators at T2 (pulmonary artery acceleration time BPD 51±17 vs no BPD 63±12 ms, p = 0.017). At T1/T2, infants with BPD had lower RV tissue Doppler velocities (e’, a’ and s) and higher E/e’ ratios (T1: BPD 10.4±2.4 vs no BPD 6.2±3.1 cm/sec, p = 0.001; T2: BPD 8.0±3.1 vs no BPD 5.6±2.6 cm/sec, p = 0.02), altered LV diastolic function (apical circumferential T1 early diastolic strain rate BPD 2.8±0.8 vs no BPD 3.6±1.0 /sec, p = 0.04; T2 late diastolic strain rate, BPD 2.29 ± 0.99 vs no BPD 1.67±0.84 /sec, p = 0.03) and LV rotational mechanics (T1: twist rate BPD 90±16 vs no BPD 130±48 deg/sec, p = 0.008; untwist rate (UTR) BPD ‐69±90 vs no BPD ‐147±68 deg/sec, p = 0.008; torsion BPD 2.78±0.56 vs no BPD 4.48±1.74 deg/cm, p = 0.009; and T2: UTR BPD ‐132±69 vs no BPD ‐179±57 deg/sec, p = 0.013). Conclusion: BPD is associated with altered RV diastolic function that persists near term, with elevated pulmonary vascular resistance, and with persistent alterations in LV apical strain rate and rotational mechanics.