Early Detection for Right Ventricular Dysfunction in Bronchopulmonary Dysplasia without Pulmonary Hypertension

Bronchopulmonary dysplasia (BPD) is a chronic lung disease associated with under development of lung tissue, mainly occurring in premature and extremely low birth weight infants. BPD has a poor prognosis in morbidity and mortality but BPD with pulmonary hypertension and right ventricular (RV) dysfunction has worse prognosis. Early detection for pulmonary hypertension and RV dysfunction is important role for determining the modality of management in BPD. There are several parameters to evaluate RV dysfunction, in this issue of the journal, Choi et al., tissue Doppler imaging (TDI)-myocardial performance index (MPI) is used to evaluate RV dysfunction in BPD. Previous studies showed difference in TDI across various BPD severities with pulmonary hypertension. Generally, the pulmonary hypertension in severe BPD result from change of pulmonary vasculature, peri-bronchiolar fibrosis, alveolar septal fibrosis and vascular muscle hypertrophy, eventually, it is common to lead RV dysfunction. A strongpoints of this study is that BPD patients in this journal had no pulmonary hypertension, no differences in TDI and only had differences in RV TDI-MPI. This result shows that RV TDIMPI is useful for early detection of RV dysfunction without pulmonary hypertension in BPD. In BPD without pulmonary hypertension, the mechanism of occurrence of RV dysfunction is still unknown and may explain multiple factor; hypoxemia, metabolic acidosis and elevated pulmonary resistance, that cause the RV myocyte dysfunction. Recently, Haque et al. report the evaluation of RV dysfunction by RV myocardial deformation imaging (MDI) using global longitudinal strain in pISSN 1975-4612/ eISSN 2005-9655 Copyright © 2016 Korean Society of Echocardiography www.kse-jcu.org https://doi.org/10.4250/jcu.2016.24.4.268