PRIMARY PULMONARY-HYPERTENSION IN CHILDREN - CLINICAL CHARACTERIZATION AND SURVIVAL

Objectives. This study characterized mortality in a group of Mexican c hildren (n = 18, mean [+/-SD] age 9.9 +/- 3 years) with primary pulmon ary hypertension and investigated the factors associated with their su rvival. Background. Primary pulmonary hypertension is a progressive, f atal disease of unknown cause. Establishing the diagnosis earlier in l ife may influence prognosis. Methods. A dynamic cohort of children wit h primary pulmonary hypertension were enrolled between December 1977 a nd May 1991 and followed up through September 1992. Measurements inclu ded hemodynamic and pulmonary function variables in addition to demogr aphic data, medical history and response to vasodilator treatment. We also compared the survival estimates of these children with those of o ur adult patients with primary pulmonary hypertension (n = 42, mean ag e 27.9 +/- 8.5 years). Results. Baseline mean (+/-SD) pulmonary artery pressure a-as similar in children and adults (66 +/- 15 vs. 65 +/- 18 mm Hg, p = NS), but a higher cardiac index resulted in a lower er mea n pulmonary vascular resistance index in children (18 +/- 7 vs. 26 +/- 12 U/m(2), p < 0.01). The proportion of patients,rho had a positive h emodynamic response to vasodilator treatment was higher in children th an in adults (41% vs. 25%). Estimated median survival in children was 4.12 years (95% confidence interval [CI] 0.75 to 8.66) and 3.12 years in adults (95% CI 0.5 to 13.25, chi-square log-rank 0.81, p = NS). Ele vated right atrial pressure (rate ratio 10.2) and decreased stroke vol ume index irate ratio 32.9) were the only significant predictors of mo rtality (Col proportional hazards model). Conclusions. Children with p rimary pulmonary hypertension have a poor survival expectancy, which d oes not appear to differ from that in adults with primary pulmonary hy pertension. Mortality in childhood primary pulmonary hypertension is a lso associated with variables that assess right ventricular dysfunctio n.