Advancements in Donor Heart Preservation Methods: A Review of Approaches

Heart transplantation remains the gold standard for end-stage heart failure, yet access is limited by geography, organ shortages, and preservation technology. In Canada, long wait times and organ underutilization persist due to the use of static cold storage (SCS), the current standard. Although SCS is cost-effective and technically simple, its short ischemic window and the inability to monitor heart function restrict donor heart viability. This review examines the evolution of preservation methods, with a focus on SCS and novel machine perfusion systems that aim to address the limitations of SCS. Hypothermic machine perfusion (HMP) and normothermic machine perfusion (NMP) both provide extended preservation times and metabolic support. HMP delivers cold, oxygenated or non-oxygenated perfusate to minimize ischemia, while NMP maintains the donor heart at body temperature in a semi-physiological state, allowing for functional monitoring and therapeutic reconditioning. Various technologies have already demonstrated success in large animal models and select clinical trials, with promising results for extended preservation intervals and DCC heart use. Normothermic regional perfusion (NRP) is a method for initial resuscitation of the DCC heart, by restoring circulation in situ before procurement and reducing ischemic injury. Its adoption in Europe and the United States (U.S.) has accelerated DCC heart donation while maintaining excellent outcomes. With new ethical guidelines supporting Canada's use, pilot programs are now possible. To improve transplant equity and maximize heart utilization, Canada can invest in machine perfusion research, infrastructure, and national implementation strategies. These technologies offer not only extended viability but also decrease waitlist mortality.