Bradycardia, increased cardiac output, and reversal of pulmonary hypertension in altitude natives living at sea level.

Eleven healthy young men native to high altitude underwent haemodynamic studies at their original place of residence and after two years' residence at sea level. The investigation sought to determine the long-term effects of the suppression of the hypoxic stimulus upon heart rate, cardiac output, and pulmonary artery pressure of highlanders. For comparative purposes the influence of oxygen inhalation at high altitude was also studied.