September 16, 2015Open Access
View Full PaperEffects of Cardiac Resynchronization Therapy on Cardiac Remodeling and Contractile Function: Results From Resynchronization Reverses Remodeling in Systolic Left Ventricular Dysfunction (REVERSE)
Key Result
Cardiac resynchronization therapy in NYHA Class I/II heart failure reduced left ventricular volumes and volume intercept (P<0.01), which was associated with mortality (HR 1.90; 95% CI 1.01-3.59).
Study Design
Type
RCT (n=610)
Structured PICO
Does cardiac resynchronization therapy improve contractility, afterload, or volumes in patients with NYHA class I/II heart failure?
P
Population
610 patients with New York Heart Association class I/II heart failure from the REVERSE study
I
Intervention
Cardiac resynchronization therapy
O
Outcome
Changes in contractility, afterload, and chamber size (volume intercept, end-systolic and end-diastolic volumes) at 6 and 12 monthssurrogate
In patients with mild heart failure, cardiac resynchronization therapy favorably reduces left ventricular volumes and the volume intercept, which is associated with mortality, rather than directly improving contractility.
Main Result
p-value: p=<0.01
Abstract
BACKGROUND: Cardiac resynchronization therapy results in improved ejection fraction in patients with heart failure. We sought to determine whether these effects were mediated by changes in contractility, afterload, or volumes. METHODS AND RESULTS: In 610 patients with New York Heart Association class I/II heart failure from the Resynchronization Reverses Remodeling in Systolic Left Ventricular Dysfunction (REVERSE) study, we performed detailed quantitative echocardiography assessment prior to and following cardiac resynchronization therapy. We derived measures of contractility (the slope end-systolic elastance and the volume intercept of the end-systolic pressure-volume relationship, stroke work, and preload recruitable stroke work), measures of arterial load and ventricular-arterial coupling, and measures of chamber size (volume intercept, end-systolic and end-diastolic volumes). At 6 and 12 months, cardiac resynchronization therapy was associated with a reduction in the volume intercept and end-systolic and end-diastolic volumes (P<0.01). There were no consistent effects on end-systolic elastance, stroke work, preload recruitable stroke work, or ventricular-arterial coupling. In the active cardiac resynchronization therapy population, baseline measures of arterial load were associated with the clinical composite score (odds ratio 1.30, 95% CI 1.04 to 1.63, P=0.02). The volume intercept was associated with mortality (hazard ratio 1.90, 95% CI 1.01 to 3.59, P=0.047) and more modestly with the combined end point of mortality or heart failure hospitalization (hazard ratio 1.48, 95% CI 0.8 to 2.25, P=0.06). In contrast, end-systolic elastance, stroke work, preload recruitable stroke work, and ventricular-arterial coupling were not associated with any outcomes. CONCLUSION: In patients with NYHA Class I/II heart failure, cardiac resynchronization therapy exerts favorable changes in left ventricular end-systolic and end-diastolic volumes and the volume intercept. The volume intercept may be useful to gain insight into prognosis in heart failure. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov/. Unique identifier: NCT00271154.