title: RV-pulmonary arterial coupling predicts outcome in patients referred for pulmonary hypertension.
abstract: OBJECTIVE
  Prognosis in pulmonary hypertension (PH) is largely determined by RV function. However, uncertainty remains about what metrics of RV function might be most clinically relevant. The purpose of this study was to assess the clinical relevance of metrics of RV functional adaptation to increased afterload.
  
  
  METHODS
  Patients referred for PH underwent right heart catheterisation and RV volumetric assessment within 48 h. A RV maximum pressure (Pmax) was calculated from the RV pressure curve. The adequacy of RV systolic functional adaptation to increased afterload was estimated either by a stroke volume (SV)/end-systolic volume (ESV) ratio, a Pmax/mean pulmonary artery pressure (mPAP) ratio, or by EF (RVEF). Diastolic function of the RV was estimated by a diastolic elastance coefficient β. Survival analysis was via Cox proportional HR, and Kaplan-Meier with the primary outcome of time to death or lung transplant.
  
  
  RESULTS
  Patients (n=50; age 58±13 yrs) covered a range of mPAP (13-79 mm Hg) with an average RVEF of 39±17% and ESV of 143±89 mL. Average estimates of the ratio of end-systolic ventricular to arterial elastance were 0.79±0.67 (SV/ESV) and 2.3±0.65 (Pmax/mPAP-1). Transplantation-free survival was predicted by right atrial pressure, mPAP, pulmonary vascular resistance, β, SV, ESV, SV/ESV and RVEF, but after controlling for right atrial pressure, mPAP, and SV, SV/ESV was the only independent predictor.
  
  
  CONCLUSIONS
  The adequacy of RV functional adaptation to afterload predicts survival in patients referred for PH. Whether this can simply be evaluated using RV volumetric imaging will require additional confirmation.
authors.affiliation: Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
authors.forename: Rebecca R
authors.identifier: http://orcid.org/0000-0001-6038-0568
authors.initials: RR
authors.lastname: Vanderpool
authors.affiliation: Heart & Vascular Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, USA Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA Department of Critical Care Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Pinsky
authors.affiliation: Free University of Brussels, Brussels, Belgium.
authors.forename: Robert
authors.initials: R
authors.lastname: Naeije
authors.affiliation: Department of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
authors.forename: Christopher
authors.initials: C
authors.lastname: Deible
authors.affiliation: School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
authors.forename: Vijaya
authors.initials: V
authors.lastname: Kosaraju
authors.affiliation: Heart & Vascular Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
authors.forename: Cheryl
authors.initials: C
authors.lastname: Bunner
authors.affiliation: Heart & Vascular Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Mathier
authors.affiliation: Department of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
authors.forename: Joan
authors.initials: J
authors.lastname: Lacomis
authors.affiliation: Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, USA Heart & Vascular Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, USA Department of Pulmonary, Allergy, and Critical Care Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
authors.forename: Hunter C
authors.initials: HC
authors.lastname: Champion
authors.affiliation: Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, USA Heart & Vascular Institute, University of Pittsburgh, Pittsburgh, Pennsylvania, USA Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
authors.forename: Marc A
authors.initials: MA
authors.lastname: Simon
mesh_terms: D000222:Adaptation, Physiological; D000328:Adult; D000368:Aged; D062186:Arterial Pressure; D006328:Cardiac Catheterization; D003971:Diastole; D018572:Disease-Free Survival; D015150:Echocardiography, Doppler; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology* / Q000628:therapy; D053208:Kaplan-Meier Estimate; D016040:Lung Transplantation; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D011446:Prospective Studies; D011651:Pulmonary Artery / Q000503:physiopathology*; D012017:Referral and Consultation; D012307:Risk Factors; D013318:Stroke Volume; D013599:Systole; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016278:Ventricular Function, Right; D017725:Ventricular Pressure