title: Circulating angiogenic modulatory factors predict survival and functional class in pulmonary arterial hypertension.
abstract: The diagnosis of pulmonary arterial hypertension (PAH) is frequently delayed. We hypothesized that circulating angiogenic modulatory protein levels might correspond with vascular remodeling activity and serve as sensitive biomarkers of PAH. Levels of soluble endoglin (sEng), soluble vascular endothelial growth factor receptor-1 (sVEGFR1), N-terminal brain natriuretic peptide (NT-proBNP), C-reactive protein (CRP), and other biomarkers were measured in peripheral blood from 97 PAH patients, 16 first-degree relatives of idiopathic or heritable pulmonary arterial hypertension (HPAH) patients, and 56 controls, and correlated with disease, functional class, hemodynamic parameters, exercise capacity, and transplant-free survival. Endoglin expression was analyzed in lung tissues of six individuals with idiopathic or HPAH and four individuals without PAH. Levels of sEng, sVEGFR1, CRP, and NT-proBNP were elevated in Group I PAH of diverse etiologies, with sEng performing better than NT-proBNP in detecting PAH (receiver operator characteristic-area-under-the curve [ROC-AUC] of 0.82 ± 0.03 vs. 0.71 ± 0.05, P = 0.016). While sEng, sVEGFR1, and NT-proBNP correlated with New York Heart Association (NYHA) class, sEng levels were more sensitive than NT-proBNP in detecting NYHA Class I-II disease (ROC-AUC of 0.88 ± 0.05 vs. 0.67 ± 0.08, P = 0.028). sEng, sVEGFR1, CRP, and NT-proBNP predicted transplant-free survival by univariate Cox regression. After adjusting for NT-proBNP levels, each of the other three markers predicted transplant-free survival. In multivariate analysis, sEng and CRP were independent predictors of survival. Endoglin expression was markedly enhanced in the microvascular endothelium and endovascular lesions of PAH versus control lung tissues. Circulating angiogenic proteins sEng and sVEGFR1 are sensitive markers of prognosis and function in Group I PAH, including mildly symptomatic disease, and may provide unique noninvasive data reflecting underlying remodeling activity.
authors.affiliation: Department of Medicine, Cardiovascular Research Center, Cardiology Division, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Rajeev
authors.initials: R
authors.lastname: Malhotra
authors.forename: Samuel
authors.initials: S
authors.lastname: Paskin-Flerlage
authors.forename: Roham T
authors.initials: RT
authors.lastname: Zamanian
authors.forename: Patrick
authors.initials: P
authors.lastname: Zimmerman
authors.forename: Jonathan W
authors.initials: JW
authors.lastname: Schmidt
authors.forename: Donna Y
authors.initials: DY
authors.lastname: Deng
authors.forename: Mark
authors.initials: M
authors.lastname: Southwood
authors.forename: Robert
authors.initials: R
authors.lastname: Spencer
authors.forename: Carol S
authors.initials: CS
authors.lastname: Lai
authors.forename: William
authors.initials: W
authors.lastname: Parker
authors.forename: Richard N
authors.initials: RN
authors.lastname: Channick
authors.forename: Nicholas W
authors.initials: NW
authors.lastname: Morrell
authors.forename: C Gregory
authors.initials: CG
authors.lastname: Elliott
authors.forename: Paul B
authors.initials: PB
authors.lastname: Yu
keywords: VEGF receptor-1; angiogenesis; biomarkers; endoglin; pulmonary arterial hypertension