The first baby to undergo a partial heart transplant will hopefully be spared repeated surgical interventions as the implanted tissue is growing with him.
The first-in-human partial heart transplant has been hailed a success, demonstrating valve growth during follow-up for more than one year.
The procedure marked the world’s first partial heart transplant, offering hope for infants with irreparable heart valve dysfunction.
A study on the case is published in the Journal of the American Medical Association.
Joseph W Turek, the lead author and chief of paediatric cardiac surgery at Duke Health, the academic and health care system based in North Carolina, US, said: ‘This publication is proof that this technology works, this idea works and can be used to help other children.’
The study also found the procedure requires about a quarter of the amount of immunosuppressant medication than a full heart transplant, potentially saving patients from detrimental side effects that might compound over decades.
Turek said the innovation has paved the way for a domino heart transplant, where one heart can save two lives.
During a domino heart transplant, a patient with healthy valves but needs stronger heart muscle receives a full heart transplant; their healthy valves are then donated to another patient in need, creating a domino effect.
He said: ‘You could potentially double the number of hearts used to benefit children with heart disease. Of all the hearts that are donated, roughly half meet the criteria to go on to be used for full transplant, but we believe there’s an equal number of hearts that could be used for valves.
‘If you introduce the donated hearts that weren’t being used in the supply chain and add the valves from domino heart transplants, that can create a substantial change.’
The partial heart transplant procedure has been performed 13 times at four centres around the world, including nine at Duke, several of which have been domino heart transplants.
Typically, these infants undergo recurrent implant exchanges until an adult-sized valve can accommodate their growing bodies.
Conducted at a paediatric referral centre, the transplant involved a recipient neonate with persistent truncus arteriosus and irreparable truncal valve dysfunction and a donor neonate with hypoxic-ischemic brain injury.
This pioneering procedure focused on transplanting a portion of the heart containing the aortic and pulmonary valves.
According to the case report, echocardiography revealed adaptive growth and excellent hemodynamic function of the transplanted valves in the recipient child, even after one year post-transplantation.
The success of this procedure suggests that partial heart transplants could revolutionise the treatment of neonates with irreparable heart valve dysfunction.
However, the postoperative care included a rigorous regimen of immunosuppressive therapies to prevent rejection of the transplanted tissue.
Despite the promising outcomes, concerns remain regarding the long-term viability of the transplanted tissue and the potential for rejection.
Monitoring of transplant markers and assessing the integration of donor and recipient cells in the vascular endothelium are crucial areas for future investigation.
Turek said bringing this innovation to a clinical trial would be the next step to achieving the volume of procedures that would significantly change the availability of hearts.
The Brett Boyer Foundation supported preclinical data. In addition to Turek, study authors include Lillian Kang, Douglas Overbey, Michael Carboni, and Taufiek K Rajab.
