Echocardiography Combined With Cardiopulmonary Exercise Testing for the Prediction of Outcome in Idiopathic Pulmonary Arterial Hypertension

• Published in: Chest Vol. 150; no. 6; pp. 1313 - 1322
• Main Authors: Badagliacca, Roberto, MD, PhD, Papa, Silvia, MD, Valli, Gabriele, MD, Pezzuto, Beatrice, MD, Poscia, Roberto, MD, PhD, Manzi, Giovanna, MD, Giannetta, Elisa, MD, PhD, Sciomer, Susanna, MD, Palange, Paolo, MD, Naeije, Robert, MD, Fedele, Francesco, MD, Vizza, Carmine Dario, MD
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-12-2016
• Subjects: cardiopulmonary exercise test; clinical worsening; Echocardiography; Exercise Test; Familial Primary Pulmonary Hypertension - diagnostic imaging; Familial Primary Pulmonary Hypertension - physiopathology; Female; Hemodynamics; Humans; Male; Middle Aged; Predictive Value of Tests; Prognosis; Prospective Studies; pulmonary arterial hypertension; Pulmonary/Respiratory; right ventricular systolic function; Ventricular Dysfunction, Right - diagnostic imaging; Ventricular Dysfunction, Right - physiopathology; mean pulmonary artery pressure; HR; LV; 6-min walk; LV-EIs; PVR; AUC; RVFAC; RVEDA; clinical worsening; left ventricular; WHO; P ET co 2; V ˙ E; V ˙ co 2 peak; World Health Organization; right ventricular; RVESA; left ventricular systolic eccentricity index; RV end-systolic area; TAPSE; cardiopulmonary exercise testing; IPAH; RA; tricuspid annular plane systolic excursion; peak carbon dioxide output; cardiopulmonary exercise test; pulmonary vascular resistance; right ventricular systolic function; mPAP; CPET; RV; echocardiography; RV end-diastolic area; end-tidal carbon dioxide; pulmonary arterial hypertension; 6MW; RV fractional area change; heart rate; SV; V ˙ o 2 peak; area under the curve; idiopathic PAH; left ventricular diastolic eccentricity index; stroke volume; minute ventilation; CW; peak oxygen uptake; PAH; right atrium; LV-EId; V˙co2 peak; V˙o2 peak; PETco2; V˙E
• ISSN: 0012-3692; 1931-3543
• DOI: 10.1016/j.chest.2016.07.036

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 O2 pulse (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 O2 pulse (low RVFAC + low O2 pulse) and high RVFAC + low O2 pulse 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 O2 pulse ( P  = .0001). Conclusions Echocardiography combined with CPET provides relevant clinical and prognostic information. A combination of low RVFAC and low O2 pulse identifies patients at a particularly high risk of clinical deterioration.