title: Pulmonary Arterial Capacitance Is an Important Predictor of Mortality in Heart Failure With a Preserved Ejection Fraction.
abstract: OBJECTIVE
  The purpose of this study was to determine the predictors of mortality in patients with pulmonary hypertension (PH) associated with heart failure with preserved ejection fraction (HFpEF).
  
  
  BACKGROUND
  PH is commonly associated with HFpEF. The predictors of mortality for patients with these conditions are not well characterized.
  
  
  METHODS
  In a prospective cohort of patients with right heart catheterization, we identified 73 adult patients who had pulmonary hypertension due to left heart disease (PH-LHD) associated with HFpEF (left ventricular ejection fraction ≥50% by echocardiography); hemodynamically defined as a mean pulmonary artery pressure ≥25 mm Hg and pulmonary artery wedge pressure >15 mm Hg. PH severity was classified according to the diastolic pressure gradient (DPG). Cox proportional hazards ratios were used to estimate the associations between clinical variables and mortality. Receiver-operating characteristic curves were used to evaluate the ability of hemodynamic measurements to predict mortality.
  
  
  RESULTS
  The mean age for study subjects was 69 ± 12 years and 74% were female. Patients classified as having combined post-capillary PH and pre-capillary PH (DPG ≥7) were not at increased risk of death as compared to patients with isolated post-capillary PH (DPG <7). A baseline pulmonary arterial capacitance (PAC) of <1.1 ml/mm Hg was 91% sensitive in predicting mortality, with better discriminatory ability than DPG, transpulmonary gradient, or pulmonary vascular resistance (area under the curve of 0.73, 0.50, 0.45, and 0.37, respectively). Fifty-seven subjects underwent acute vasoreactivity testing with inhaled nitric oxide. Acute vasodilator response by the Rich or Sitbon criteria was not associated with improved survival.
  
  
  CONCLUSIONS
  PAC is the best predictor of mortality in our cohort and may be useful in describing phenotypic subgroups among those with PH-LHD associated with HFpEF. Acute vasodilator testing did not predict outcome in our cohort but needs to be further investigated.
authors.affiliation: Department of Medicine, Tufts Medical Center, Boston, Massachusetts.
authors.forename: Nadine
authors.initials: N
authors.lastname: Al-Naamani
authors.affiliation: Department of Medicine, Tufts Medical Center, Boston, Massachusetts.
authors.forename: Ioana R
authors.initials: IR
authors.lastname: Preston
authors.affiliation: Tufts Clinical and Translational Science Institute, Boston, Massachusetts.
authors.forename: Jessica K
authors.initials: JK
authors.lastname: Paulus
authors.affiliation: Department of Medicine, Tufts Medical Center, Boston, Massachusetts.
authors.forename: Nicholas S
authors.initials: NS
authors.lastname: Hill
authors.affiliation: Department of Medicine, Tufts Medical Center, Boston, Massachusetts. Electronic address: kroberts@tuftsmedicalcenter.org.
authors.forename: Kari E
authors.initials: KE
authors.lastname: Roberts
mesh_terms: D000368:Aged; D006328:Cardiac Catheterization; D005260:Female; D006333:Heart Failure / Q000150:complications / Q000401:mortality* / Q000503:physiopathology; D006801:Humans; D006976:Hypertension, Pulmonary / Q000209:etiology; D008297:Male; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D011446:Prospective Studies; D011651:Pulmonary Artery / Q000503:physiopathology; D011669:Pulmonary Wedge Pressure / Q000502:physiology*; D012372:ROC Curve
keywords: heart failure with preserved ejection fraction; pulmonary heart disease; survival; vasodilation