Abstract
PURPOSE: Ischemic myocardial contracture (IMC) or "stone heart" is a condition with rapid onset following circulatory death. It inhibits transplantability of hearts donated upon circulatory death (DCD). We investigate the effectiveness of hemodynamic normalization upon withdrawal of life-sustaining therapy (WLST) in a large-animal controlled DCD model, with the hypothesis that reduction in cardiac work delays the onset of IMC. METHODS: A large-animal study was conducted comprising of a control group ([Formula: see text]) receiving no therapy upon WLST, and a test group ([Formula: see text]) subjected to a protocol for fully automated computer-controlled hemodynamic drug administration. Onset of IMC within 1 h following circulatory death defined the primary end-point. Cardiac work estimates based on pressure-volume loop concepts were developed and used to provide insight into the effectiveness of the proposed computer-controlled therapy. RESULTS: No test group individual developed IMC within [Formula: see text], whereas all control group individuals did (4/6 within [Formula: see text]). CONCLUSION: Automatic dosing of hemodynamic drugs in the controlled DCD context has the potential to prevent onset of IMC up to [Formula: see text], enabling ethical and medically safe organ procurement. This has the potential to increase the use of DCD heart transplantation, which has been widely recognized as a means of meeting the growing demand for donor hearts.