Unexplained pulmonary hypertension in children in the highlands of Papua New Guinea.

We report the clinical features, electrocardiographic and chest X-ray findings, and Doppler-measured pulmonary artery pressures in 22 children admitted to Goroka Base Hospital with primary pulmonary hypertension and compare them with findings in 10 controls. Symptoms frequently reported by patients were recurrent cough (95%) and shortness of breath (77%). 82% of the patients had increased intensity of the pulmonary component of the second heart sound. 45% of the patients had clinical evidence of right heart failure. Chest X-rays were readable in 14 patients: the mean cardio-thoracic ratio was 65% and in the controls 58%; the mean diameter of the descending branch of the right pulmonary artery was 9 mm and in the controls 6.4 mm. 13 patients and 8 controls had electrocardiograms: 11 patients had right axis deviation, 2 a normal axis, and all showed evidence of right ventricular hypertrophy; 7 controls had a normal axis, 1 had right axis deviation, and 3 controls had right ventricular hypertrophy. Pulmonary artery pressures in the patients ranged from 41 to 137 mmHg with a mean of 79 mmHg. The control group had a mean pulmonary artery pressure of 28 mmHg, but 5 of the 10 controls had pulmonary artery pressures greater than the accepted norm (peak systolic pressure less than 30 mmHg). Altitude and chest infection may be playing a role in the pathogenesis of pulmonary hypertension in patients in the highlands but further studies need to be done to define the causes and the pathological changes in the pulmonary vasculature, as well as to determine local norms and the natural history of pulmonary hypertension in highland children.