Preservation of Cardiac Extracellular Matrix by Passive Myocardial Restraint

Congestive heart failure is a burgeoning problem, especially in older adults, affecting nearly 0.1% of subjects >65 years old, accounting for nearly 20% of all hospitalizations in this age group, and costing the healthcare system a bundle.1 Several experimental observations have demonstrated an important role for progressive dilation and geometric remodeling of the left ventricle in worsening cardiac pump function.2 The results of experimental studies on the adverse implications of ventricular dilation and remodeling have been confirmed in clinical and epidemiological studies of depressed ventricular function and congestive heart failure in humans.2,3 Studies of the natural history of left ventricular dysfunction provide evidence to directly implicate left ventricular dilation and remodeling to an adverse clinical outcome in patients with congestive heart failure. Ventricular dilation and remodeling impose an increased mechanical disadvantage to the pump function by increasing wall stress and consequently the hemodynamic load and by contributing to mitral regurgitation and possibly arrhythmogenesis in patients with congestive heart failure independently of the neurohormonal status. Therapeutic trials have also shown that the majority of clinically useful and approved treatment modalities in heart failure attenuate or reverse ventricular dilation and remodeling.4–8 Despite multiple drug therapies, including neurohormonal blockade, progressive ventricular dilation and adverse remodeling frequently continue in many patients with depressed ventricular function. Although orthotopic cardiac transplantation is highly successful in alleviating heart failure and improving survival, limited donor supply, organ rejection, and complications related to immunosuppressive therapy continue to limit the utility of this procedure. In recent years, several new nonpharmacological approaches for attenuation and or reversal of ventricular dilation and remodeling have been introduced, including partial ventricular resection or the Batsita procedure, the endoventricular patch repair or the Dor procedure, and cardiac resynchronization therapy with biventricular pacing.9 The idea for a passive restraining device to …