[Primary or of unknown etiology pulmonary hypertension: survival and its determinants]

The main objective of the present study is to characterize mortality in PPH and the factors associated with survival. Our series comprises 61 patients diagnosed of PPH and prospectively followed at the Cardiopulmonary Department between the years of 1977 and 1992. Univariate and multivariate analysis were used to examine relations between survival and selected demographic, medical-history, pulmonary-function, laboratory, and hemodynamic variables. We used the date of initial diagnostic catheterization as an index for determining survival. The method of Kaplan-Meir was used to estimate overall survival distribution.

the mean age of the group was 22.6 +/- 11 years with a female to male ratio of 3.06:1. Pulmonary hemodynamics at entry were: mean pulmonary artery pressure (PAP) = 65.5 +/- 17.5 mmHg; right atrial pressure (RAP) = 7.5 +/- 5 mmHg; cardiac index (CI) = 3.15 +/- 1.31.mi.m2; pulmonary vascular resistance (RP) = 24 +/- 11 U. The pulmonary to systemic resistance ratio (Rp/Rs) was 0.8 +/- 0.2. The median survival (MS) of the whole group 4.04 years. There was a significant difference in MS between the groups with and without vasodilator treatment (5.04 and 2.12 years respectively), however, the hemodynamic profile at entry was also different, with higher RAP, PAP, PVR, and higher Rp/Rs in the group without treatment (p < 0.05). Factors associated with poor survival (univariate) were: increased RAP, RP, and Rp/Rs and decreased forced vital capacity (FVC), decreased CI, and stroke volume index and decreased mixed venous PO2. The absence of vasodilator treatment was also associated with an increased risk of death. On the multivariate analysis, survival was associated mainly to FVC and to pulmonary hemodynamic variables. We conclude that survival in PPH is related to pulmonary hemodynamic factors at diagnosis.