Extending a Donor Heart's Life
Dr. Stepheny Zani - 2 February 2026
First author, Dr. Fulin Wang
If you ever watched a medical TV show before you probably can imagine this scenario: in a surgical room there is an organ donor in a bed and next to them, in another bed, is the recipient, quickly receiving the donated organ within minutes. In reality, however, donors and recipients are not in the same hospital, maybe not in the same city or even in the same country. Doctors rush to transport the organ while keeping it alive for the next hours before it is transplanted. What happens during those hours is crucial to ensure organ survival and only the first step towards a successful transplant.
We need to consider two key points when talking about transplants. One is the availability of donated organs. The second, the survival of the organ until it is transplanted. To address the shortage of donated organs, several countries have approved donations after circulatory death (DCD) - when the heart stops beating. However, the hearts were usually not considered for transplant, due to a problem called ischemia-reperfusion damage. Quite literally it means the heart has trouble when blood flow to the heart is reduced and then returned to normal.
More recently, we’ve seen an increase in the DCD hearts being transplanted in the US, UK and Australia, but in Canada, the number still remains low. Now that DCD hearts are approved for transplantation, we need to improve organ survival, enhancing the chances of a successful transplant.
When an organ is transplanted, in the recipient’s body it is referred to as a “graft”. For the transplant to be successful the recipient’s body needs to accept the new organ. Graft rejection is a challenge faced by transplant surgeons and researchers trying to find ways to improve transplant outcomes. Finding ways to improve graft survival of these hearts is a crucial step in this life-saving effort.
One way to increase heart viability outside the body - also known as ex situ - is to perfuse them with nutrients and medicines to support their survival. This overly simplified description refers to a procedure appropriately named ex situ perfusion. In a previous study, Drs. Fulin Wang and Michael Zaugg revealed that a specific perfusion formula based on pharmacological principles, using a mixture of Intralipid/sevoflurane/remifentanil, preserved the function and viability of porcine hearts. They saw an increase in metabolism that stabilized the cells and prevented lipid accumulation inside the cells.
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With this in mind, in their recent publication in the Journal of Heart and Lung Transplantation Dr. Zaugg’s team led by Dr. Fulin Wang, dove deeper into the benefits of perfusion focusing on the molecular changes happening in the heart after circulatory death. Their results were so dramatic they may change how we see transplants in the hospital and maybe even on TV.
It’s best to point out that when heart muscle loses oxygen and nutrients, the cells tend to die off. When these vital requirements are restored, the heart also becomes inflamed and undergoes a process called remodelling to regain what has been lost. The group found that porcine hearts tend to experience high levels of inflammation and poor remodelling when ex situ, similar to what happens in heart failure. When the hearts are perfused with the formula, there is still that inflammation and remodelling, but to a lesser degree that is beneficial to the heart’s survival.
But there’s more.
The two different formulas used to perfuse the hearts led to the production of different molecular messengers that regulate survival, such as microRNAs. microRNAs modulate gene transcription, consequently deciding genes will be more or less expressed. In the case of untreated hearts their microRNA profile pointed towards an injured heart, linked with inflammation and cellular death. Therefore, compared to treated hearts, not having the drug cocktail in their bath severely impaired the hearts impacting their future survival post transplant.
Their work reveals that although ex situ perfusion might still cause some damage to the heart, using a cardioprotective drug cocktail prevented severe damage, increasing the viability of the hearts for a posterior transplant. The authors know that more work is needed to validate the findings in humans, but their work shows promise in improving donated organ survival. While we keep wondering if the medical TV shows are true to reality with patients successfully recovering after hours waiting for a heart coming from afar, this team has shown that, in this case, the waiting hours in between may ultimately determine transplant success.