Abstract 9569: Assessment of Bi-ventricular Functional Reserve During Dobutamine Stress Offers a Significant Prognostic Impact for Patients With Dilated Cardiomyopathy
Background: Right ventricular (RV) function has been increasingly recognized as an important prognostic factor for heart failure patients as well as left ventricular (LV) function. The objective of this study was thus to investigate the prognostic importance of RV functional reserve in patients with dilated cardiomyopathy (DCM), and whether combined assessment of bi-ventricles can further enhance the prognostic evaluation.
Methods: Seventy-three DCM patients with ejection fractions of 32±9% were recruited, and speckle-tracking echocardiography was used to assess both RV and LV functional reserve under dobutamine stress (20 mg/kg/min). RV contractile function was determined as peak global longitudinal strain from RV free wall (RV-free), whereas LV contractile function was calculated by averaging of peak global longitudinal strain from standard apical views (GLS). Event-free survival was tracked over an 18-month.
Results: Multivariate Cox proportional-hazards analysis revealed that RV-free during dobutamine stress (ΔRV-free) as well as that in GLS (ΔGLS) were the two major independent predictors of cardiovascular events (p<0.001 and p=002, respectively). The Kaplan-Meier curve analysis disclosed that patients with RV reserve (ΔRV-free ≥16.5%) and with LV reserve (ΔGLS ≥10.0%) had a significantly better prognosis than those without (log rank p<0.01, respectively). Of special interest was that a pattern of both RV and LV functional reserve was associated with favorable outcome, whereas a pattern of neither RV nor LV functional reserve was associated with poor outcome (event rate: 2.3% vs. 82%, p<0.001). Patients with heterogeneous pattern of either RV or LV functional reserve had an intermediate risk of cardiac events (26.3%).
Conclusions: RV functional reserve as well as LV was associated with prognostic impact in patients with DCM. Combined assessment of bi-ventricular functional reserve may play a key role for better management of such patients.
- © 2013 by American Heart Association, Inc.