Reverse remodeling and enhanced inotropic reserve from the cardiac support device in experimental cardiac failure.

Progressive chamber remodeling plays a major role in the pathophysiology of chronic cardiac failure. Recent studies have begun exploring the potential for a passive external containment to impede such progressive dilation. In dogs with ischemic dilated cardiomyopathy, surgical placement of a thin external polyester mesh led to reversal of chronic chamber dilation after 3 to 6 months. Systolic function was preserved compared with the earlier time point. Both end-systolic and end-diastolic chamber volumes were reduced by about 20%, whereas end-diastolic pressure and chamber diastolic stiffness were not altered. These findings differ from the natural progression of this model, which involves progressive dilation and systolic dysfunction. In conjunction with reverse remodeling, cardiac inotropic reserve to beta-receptor agonists was markedly enhanced. Furthermore, these changes were induced without adversely affecting Frank-Starling reserve, supporting the lack of constriction.