title: Echocardiography Combined With Cardiopulmonary Exercise Testing for the Prediction of Outcome in Idiopathic Pulmonary Arterial Hypertension.
abstract: BACKGROUND
  Right ventricular (RV) function is a major determinant of exercise intolerance and outcome in idiopathic pulmonary arterial hypertension. The aim of the study was to evaluate the incremental prognostic value of echocardiography of the right ventricle and cardiopulmonary exercise testing (CPET) on long-term prognosis in these patients.
  
  
  METHODS
  One hundred and thirty treatment-naïve patients with idiopathic pulmonary arterial hypertension were enrolled and prospectively followed. Clinical worsening (CW) was defined by a reduction in 6-min walk distance plus an increase in functional class, or nonelective hospitalization for PAH, or death. Baseline evaluation included clinical, hemodynamic, echocardiographic, and CPET variables. Cox regression modeling with c-statistic and bootstrapping validation methods were done.
  
  
  RESULTS
  During a mean period of 528 ± 304 days, 54 patients experienced CW (53%). Among demographic, clinical, and hemodynamic variables at catheterization, functional class and cardiac index were independent predictors of CW (model 1). With addition of echocardiographic and CPET variables (model 2), peak O2pulse (peak V˙o2/heart rate) and RV fractional area change (RVFAC) independently improved the power of the prognostic model (area under the curve, 0.81 vs 0.66, respectively; P = .005). Patients with low RVFAC and low O2pulse (low RVFAC + low O2pulse) and high RVFAC + low O2pulse showed a 99.8 and 29.4 increase in the hazard ratio, respectively (relative risk, 41.1 and 25.3, respectively), compared with high RVFAC + high O2pulse (P = .0001).
  
  
  CONCLUSIONS
  Echocardiography combined with CPET provides relevant clinical and prognostic information. A combination of low RVFAC and low O2pulse identifies patients at a particularly high risk of clinical deterioration.
authors.affiliation: Department of Cardiovascular and Respiratory Science, Sapienza University of Rome, Italy. Electronic address: roberto.badagliacca@uniroma1.it.
authors.forename: Roberto
authors.initials: R
authors.lastname: Badagliacca
authors.affiliation: Department of Cardiovascular and Respiratory Science, Sapienza University of Rome, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Papa
authors.affiliation: Department of Cardiovascular and Respiratory Science, Sapienza University of Rome, Italy.
authors.forename: Gabriele
authors.initials: G
authors.lastname: Valli
authors.affiliation: Department of Cardiovascular and Respiratory Science, Sapienza University of Rome, Italy.
authors.forename: Beatrice
authors.initials: B
authors.lastname: Pezzuto
authors.affiliation: Department of Cardiovascular and Respiratory Science, Sapienza University of Rome, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Poscia
authors.affiliation: Department of Cardiovascular and Respiratory Science, Sapienza University of Rome, Italy.
authors.forename: Giovanna
authors.initials: G
authors.lastname: Manzi
authors.affiliation: Department of Experimental Medicine, Sapienza University of Rome, Italy.
authors.forename: Elisa
authors.initials: E
authors.lastname: Giannetta
authors.affiliation: Department of Cardiovascular and Respiratory Science, Sapienza University of Rome, Italy.
authors.forename: Susanna
authors.initials: S
authors.lastname: Sciomer
authors.affiliation: Department of Clinical Medicine, Sapienza University of Rome, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Palange
authors.affiliation: Department of Cardiology, Erasme University Hospital, Brussels, Belgium.
authors.forename: Robert
authors.initials: R
authors.lastname: Naeije
authors.affiliation: Department of Cardiovascular and Respiratory Science, Sapienza University of Rome, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Fedele
authors.affiliation: Department of Cardiovascular and Respiratory Science, Sapienza University of Rome, Italy.
authors.forename: Carmine Dario
authors.initials: CD
authors.lastname: Vizza
mesh_terms: D004452:Echocardiography; D005080:Exercise Test; D065627:Familial Primary Pulmonary Hypertension / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D018497:Ventricular Dysfunction, Right / Q000000981:diagnostic imaging / Q000503:physiopathology
keywords: cardiopulmonary exercise test; clinical worsening; echocardiography; pulmonary arterial hypertension; right ventricular systolic function