Correlation of Atrial Natriuretic Factor and Renin-Aldosterone System With Chronic Pulmonary Hypertension Among Residents in a High Altitude.

The study was performed to evaluate right ventricular contractility, plasma renin activity, and atrial natriuretic peptide in high altitude pulmonary arterial hypertension (HAPH). Sixty-eight patients with signs of pulmonary artery hypertension (PPA,syst > 25 mmHg, PPA > 15 mmHg) (Group II) and 40 with normal coronary angiograms and normal pulmonary artery pressures (Group I) were included in the study. Right heart catheterization with estimation of right ventricular and pulmonary artery pressures were performed in all the patients. The blood samples were taken from the pulmonary artery for measurement of mean oxygen saturatioýn (SaO2), atrial natriuretic factor (ANF) level, plasma renin activity (PRA), aldosterone level, and sodium and potassium concentrations. Statistical analysis was performed using unpaired Student's t test and linear regression analysis. The patients with HAPH had higher pulmonary artery pressures (PPA,syst, PPA, PPA,diast), total pulmonary resistance (Rpulm,tot), and right ventricular systolic pressure (PRv,syst). The significant correlation was found between ANF and PRA with right ventricular contractility indices and pulmonary vascular resistance.