Advanced therapy for pulmonary arterial hypertension due to congenital heart disease: a clinical perspective in a new therapeutic era

Pulmonary arterial hypertension (PAH) is a progressive disease with poor survival. PAH is classified by the 2009 updated clinical classification of pulmonary hypertension and a major subgroup is PAH due to congenital heart disease (CHD) with systemic-to-pulmonary shunt [1]. This shunting may lead to extensive histological changes in the distal pulmonary arteries resulting in an irreversible increase in pulmonary vascular resistance (PVR). The classification of CHD-PAH includes four categories: (1) Eisenmenger syndrome, (2) PAH associated with systemicto-pulmonary shunts, (3) PAH with small septal defects, and (4) PAH after corrective cardiac surgery [2]. In these patients advanced pharmacological therapy should be considered. Three classes of advanced therapy for PAH are currently in use: prostanoids such as epoprostenol, endothelin-1 receptor antagonists such as bosentan, and phosphodiesterase 5 inhibitors such as sildenafil [3]. Bosentan has been shown to improve 6-min walking distance (6MWD) and to decrease PVR in patients with Eisenmenger syndrome [4]. Anecdotal experience with the phosphodiesterase type-5 inhibitors sildenafil and tadalafil show favourable functional and haemodynamic results in patients with CHD-PAH [5, 6]. We present three patients treated with advanced pharmacological therapy for CHD-PAH: a patient with Eisenmenger syndrome receiving standard care, a patient with atrial septal defect receiving advanced therapy as a bridge to surgery, and a patient with segmental PAH who was started on advanced therapy empirically.