Rapid regression of primary pulmonary hypertension

A 14 month old child presented for investigation of tachypnoea. No parenchymal lung disease was shown on chestx ray. On echocardiography there was normal intracardiac anatomy with significant pulmonary hypertension. At cardiac catheterisation the presence of primary pulmonary hypertension was confirmed, with a partial response to inhaled nitric oxide (80 ppm) and 100% oxygen. The child was referred for assessment for heart–lung transplantation while maintained on oxygen, inhaled nitric oxide, and nifedipine. Repeat cardiac catheterisation two months after presentation showed complete normalisation of the pulmonary artery pressures.