Reversing Heart Failure: Diastolic Recoil in a Proposed Cardiac Support Device

Abstract

Congestive heart failure (CHF) holds millions in the grip of an endless cycle of decreased cardiac output and degenerative remodeling, often with little hope of recovery. Diastolic dysfunction, or failure of the heart to properly fill, is a contributing factor to all cases of CHF and is the sole cause of many cases. By storing energy during systole that can be released during diastole, the addition of a diastolic recoil component to an existing systolic support device could aid in inducing restorative remodeling and, thus, interrupt the downward spiral of heart failure. In this study we use an indicator of diastolic function-the end-diastolic pressure-volume relationship (EDPVR)-to demonstrate in vitro the ability of a prototype device to positively impact the entire heart cycle. The support device alone shifts the EDPVR of a model heart towards smaller volumes. When the diastolic recoil component is employed, the EDPVR is shifted towards lower pressures at low volumes, indicating stiffer diastolic recoil. We conclude the device provides bi-phasic support of our model heart, constraining over-filling of the ventricles and augmenting ventricular recoil.