PURPOSE:Treatment guidelines for PAH rely mainly on functional class in guiding aggressiveness of therapy. There is limited evidence as to the incremental prognostic value of clinical and hemodynamic factors in a large contemporary cohort of patients with PAH.
METHODS:The original medical records of all adult PAH seen between 1/1/1995–12/31/2004 were reviewed. Predictors of mortality were assessed sequentially using Cox models, first considering only echo and PFT findings and finally RHC findings.
RESULTS:The study included 657 PAH patients with a mean age of 53.6 (±15.9) years and 77% were female. Mean disease duration at start of follow-up was 2.4 (±2.7) years. A total of 366 (55.7%) subjects had IPAH and 154 (23.4%) subjects had PAHc with median survival of 3.8 and 2.8 years, respectively. Females had a lower risk of death than males (HR: 0.67, 95% CI 0.53, 0.85). In analyses adjusted for age, sex, functional class and baseline 6-min walk, various echo, RHC and PFT findings were significant predictors of mortality. In multivariable analyses that included age, sex, functional class and baseline 6-min walk test, RV enlargement (HR: 1.43, 95% CI 1.10, 1.86), pericardial effusion (HR: 1.37, 95% CI 1.07, 1.76) and % DLCO (HR: 0.98, 95% CI 0.97, 0.99) remained significant predictors of mortality. Upon inclusion of RHC findings, RA pressure (HR: 1.03, 95% CI 1.01, 1.06), pulmonary vascular resistance index (HR: 1.02, 95% CI 1.00, 1.04) and vasodilator response (HR: 0.93, 95% CI 0.88, 0.99 per 10% decrease in pvri) predicted mortality. Concordance index (C statistic) showed that echo hemodynamic variables significantly improved the prediction of a model that already included age, sex and functional class (0.686 vs. 0.734).
CONCLUSION:These findings indicate the additive predictive value of clinical, echocardiographic and invasive hemodynamic variables in the prediction of survival in PAH patients.
CLINICAL IMPLICATIONS:There is a need to extend the treatment guidelines beyond functional class to also include these factors.
DISCLOSURE:Garvan Kane, Grant monies (from industry related sources) This study was supported by an unrestricted grant from Pfizer; No Product/Research Disclosure Information