Abstract 14534: Right Heart Load Adaptability is Predictive of Outcomes in Patients With Pulmonary Arterial Hypertension
Introduction: Right heart failure is a major cause of death in patients with pulmonary arterial hypertension (PAH). This study aimed at defining right ventricular (RV) adaptation to afterload, and assessing the link with long-term outcomes.
Hypothesis: We hypothesized that load-adaptation would be prognostic in patients with PAH.
Methods: Eighty-five consecutive patients with PAH underwent echocardiography within 4 hours before catheterization, from 2000 and 2009. End-systolic area (RVESA) index, fractional area change (RVFAC), tricuspid annular plane systolic excursion (TAPSE), and free-wall longitudinal strain were measured. Load was defined by vascular resistance index (PVRI), capacitance index (PACI), arterial elastance and RV estimated wall stress (RV systolic pressure x RVESA x 0.5)/(end-systolic length x wall thickness). Regression models were used to define the relationship between function and load; and Cox models to determine correlates of death or lung transplant during follow-up (5 years).
Results: Relationships between function metrics and afterload followed curvilinear fits (all p<0.01). PVRI, PACI and wall stress were more strongly associated to RVFAC and RVESAI than TAPSE or strain. Load-adaptation indices were derived from the power functions. Estimated single-year survival rates were 84.7% at 1 year, and 63.5% at 5 years. Using multivariate analysis, RVESAI/PVRI0.35, RVESAI/PACI-0.43 and RVESAI/WS0.48 were significantly correlated to the combined endpoint (Hazard Ratio per standard deviation 1.65 95%CI [1.20-2.27], 1.75 [1.26-2.49], 1.54 [1.10-2.14], all p≤0.01), independently of right atrial pressure. Adding load-adaptability index level was able to re-stratify patients with moderate to severe RV enlargement or dysfunction (Figure).
Conclusions: Right ventricular adaptation to afterload can be modeled by curvilinear functions, defining prognostic load-adaptation indices.
Author Disclosures: M. Amsallem: None. D. Boulate: None. Z. Kooreman: None. M. Aymami: None. G. Fadel: None. A. Denault: None. M.V. McConnell: None. O. Mercier: None. E. Fadel: None. M. Rabinovitch: None. R.T. Zamanian: None. F. Haddad: None.
- © 2016 by American Heart Association, Inc.