Mild Elevation of Pulmonary Arterial Pressure as a Predictor of Mortality

Rationale: Normal mean pulmonary arterial pressure (mPAP) is 14.0 ± 3.3 mm Hg (mean ± SD). The prognostic relevance of mildly elevated mPAP not fulfilling the definition of pulmonary hypertension (PH; mPAP ≥ 25 mm Hg) has not been prospectively evaluated in a real-world setting.Objectives: To assess the association of resting mPAP with all-cause mortality in a retrospective and a prospective cohort of patients with unexplained dyspnea and/or at risk of PH.Methods: Prognostic cutoffs were calculated by means of 1) classification and regression tree (CART) analysis without any preset thresholds, and 2) preset thresholds on the basis of literature data defining mPAP as lower-normal (≤mean + 1 SD), upper-normal (between mean + 1 SD and mean + 2 SD), borderline (between mean + 2 SD and 25 mm Hg), and manifest PH (≥25 mm Hg). We performed univariate and multivariate survival analysis adjusted for age and comorbidities.Measurements and Main Results: We enrolled 547 patients, of whom 137, 56, 64, and 290 presente...