Persistent Pulmonary Hypertension of the Newborn: Physiology, Hemodynamic Assessment and Novel Therapies

Persistent pulmonary hypertension of the newborn (PPHN) remains a serious disorder with significant mortality and long term morbidity. Inhaled nitric oxide is the only approved vasodilator therapy in neonates, but 40% of infants are non-responders. Recent biological evidence has enhanced our understanding of the cellular mechanisms involved in cardiopulmonary transition at birth, paving the way for potential alternate therapies as published in recent reviews. Optimal clinical care of infants with PPHN necessitates a comprehensive understanding and evaluation of cardiopulmonary hemodynamics. Targeted neonatal echocardiography (TnECHO) is increasingly being implemented to guide clinical decision making. The purpose of this review is to outline the role of TnECHO in better defining the cardiopulmonary physiology in PPHN and its application in clinical practice. In addition we briefly review the physiology, pathogenesis and novel therapeutic agents currently under investigation for management of PPHN.