Objectives: The objective of this study was to compare the physiological determinants of ejection fraction (EF)-ventricular size, contractile function, and ventricular-arterial (VA) interaction-and their associations with clinical outcomes in chronic heart failure (HF).
Background: EF is a potent predictor of HF outcomes, but represents a complex summary measure that integrates several components including left ventricular size, contractile function, and VA coupling. The relative importance of each of these parameters in determining prognosis is unknown.
Methods: In 466 participants with chronic systolic HF, we derived quantitative echocardiographic measures of EF: cardiac size (end-diastolic volume [EDV]); contractile function (the end-systolic pressure volume relationship slope [Eessb] and intercept [V0]); and VA coupling (arterial elastance [Ea]/Eessb). We determined the association between these parameters and the following adverse outcomes: 1) the combined endpoint of death, cardiac transplantation, or ventricular assist device (VAD) placement; and 2) cardiac hospitalization.
Results: Over a median follow-up of 3.4 years, there were 76 deaths, 52 transplantations, 14 VAD placements, and 684 cardiac hospitalizations. EF was independently associated with death, transplantation, and VAD placement (adjusted hazard ratio [HR]: 3.0; 95% confidence interval [CI]: 1.8 to 5.0 comparing third and first tertiles), as were EDV (HR: 2.6; 95% CI: 1.5 to 4.2); V0 (HR: 3.6; 95% CI: 2.1 to 6.1); and Ea/Eessb (HR: 2.1; 95% CI: 1.3 to 3.3). EDV, V0, and Ea/Eessb were also associated with risk of cardiac hospitalization. Eessb was not significantly associated with any adverse outcomes in adjusted analyses.
Conclusions: Left ventricular size, V0, and VA coupling are associated with prognosis in systolic HF, but end-systolic elastance (Eessb) is not. Assessment of VA coupling via Ea/Eessb is an additional noninvasively derived metric that can be used to gauge prognosis in human HF.
Keywords: CI; CV; EDV; EF; ESP; ESPVR; ESV; Ea; Ea/Ees(sb); Ees; Ees(sb); HF; HR; IQR; LV; LVOT; N-terminal pro–B-type natriuretic peptide; NT-proBNP; NYHA; New York Heart Association; SV; V(0); V(100); VA; VAD; arterial elastance; coefficient of variation; confidence interval; ejection fraction; end-diastolic volume; end-systolic elastance; end-systolic elastance, single beat; end-systolic pressure volume; end-systolic pressure-volume relationship; end-systolic volume; hazard ratio; heart failure; interquartile range; left ventricular; left ventricular outflow tract; mechanics; stroke volume; ventricular assist device; ventricular volume at an end-systolic pressure of 100 mm Hg; ventricular volume at an end-systolic pressure of 0 mm Hg; ventricular-arterial; ventricular-arterial coupling, single beat.
Copyright © 2013 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.