Conference: 2008 International PHA Conference and Scientific Sessions
Release Date: 06.20.2008
Presentation Type: Abstracts
Frantz R.P.1, Robbins I.M.2, Durst L.A.1, Grill D.E.1, McGoon M.D.1, Burnett J.C.1
1. College of Medicine, Mayo Clinic, Rochester, MN, USA
2. Vanderbilt University, Nashville, TN, USA
BACKGROUND: Biomarkers in PAH may be useful in assessing prognosis.
METHODS: Patients with Group I PAH (n=88) underwent measurement of plasma ET-1, Big-ET, BNP, N-terminal ANP and NE. Kaplan-Meier plots for time to combined endpoint of death or transplant were created. Multivariate analysis including neurohormones, WHO class and 6 minute walk distance was performed.
RESULTS: Age 48 ± 14 years, 81% female, 90% idiopathic, 5% CTD, 5% congenital, 6 min walk distance 348 ± 130 m, WHO functional class I, II, III, IV: 5%, 35%, 50%, 10%, PA mean 60 ± 10 mm Hg, Cardiac index 2.2 ± 0.8 L/min/m2. Patients in the highest quartile of ET-1 or BNP had hazard ratios for death or transplant of 4.4 (95% CI 1.7-11.7, p = 0.003) and 2.9 (95% CI 1.35-6.4, p = 0.007) respectively. A trend was present for highest quartile of N-ANP (Hazard ratio 2.3, 95% CI 0.91-5.7, p = .08).
CONCLUSIONS: Elevated ET-1 or BNP plasma levels are independent risk factors for death or transplantation in PAH. Association of elevated ET-1 with adverse prognosis suggests participation of ET-1 in the progression of PAH. ET-1 levels would not be expected to be predictive of outcome in patients already treated with ET antagonists due to effects of those agents on ET-1 clearance. We confirm that BNP is predictive of outcome and add evidence to the rationale for measuring BNP and ET-1 in patients with PAH.