Reverse of Left Ventricular Volumetric and Structural Remodeling in Heart Failure Patients Treated With Cardiac Resynchronization Therapy

Reverse changes in cardiac substrate oxidation in dogs recovering from heart failure

“…Specifically, we found that: 1) baseline hemodynamics returned to control level, while ejection fraction and ␤-adrenergic response were still partially depressed compared with control; 2) LV was still dilated, its walls, as well as cardiomyocyte cross-sectional area, were thinner than control, and heart weight was increased; and 3) baseline FFA and glucose oxidation were normalized, but showed no increase in response to pacing stress, while activities of aconitase and citrate synthase remained lower than control. The increasing use of cardiac support devices and resynchronization therapy to sustain cardiac function in HF patients has stimulated a strong interest in the processes of reverse remodeling (7,17,25). In particular, a remarkable cellular and molecular plasticity of failing myocardium in response to mechanical unloading has been shown in tissue samples harvested from patients supported by LV assist devices and awaiting cardiac transplant (3,5,11,32).…”

“…In conclusion, cardiac energy substrate utilization is normalized in the early stage of post-HF recovery at baseline, but not under stress conditions. dilated cardiomyopathy; fatty acids; glucose; tachypacing THE CAPACITY OF THE FAILING heart to recover and restore, at least in part, a normal structure and function has been well demonstrated, both in animal models (12,13,26,28) and in patients (3,25). In pacing-induced heart failure (HF), an established model of dilated cardiomyopathy, hemodynamic and neurohormonal alterations, as well as myocyte function, return to control level within the first 2 wk of recovery after discontinuation of cardiac stimulation (28).…”

The Year in Heart Failure

“…In the CARE-HF study population, greater interventricular mechanical delay, more severe cardiac dyssynchrony, and low systolic blood pressure appeared to obtain greater benefits from CRT (86). Clearly, "responders" to CRT often demonstrate reversal of cardiac remodeling and morphologic as well as molecular improvement (87)(88)(89). The results of the PROSPECT (Predictors of Response to Cardiac Resynchronization Therapy) study (90) demonstrated that in the 69% of the 426 patients who improved following CRT, no single echocardiographic measure of dyssynchrony was reliable in predicting responders, which can be attributable in part to interobserver variability when making these measurements.…”

Mechanistic Evaluation of Echocardiographic Dyssynchrony Indices

“…Analogously, simulated CRT response was defined as the "acute" change of LVESV after restoration of synchronous ventricular activation and subsequent simulation of 50 cardiac cycles, allowing hemodynamic stabilization. In this approach, dyssynchronyinduced structural and contractile remodeling as well as resynchronization-induced reverse remodeling [33][34][35] have not been taken into account.…”