Using normothermic machine perfusion in simultaneous heart and liver transplants could save more lives

March 26, 2024

The use of combined heart and liver transplantation (CHLT) to treat multi-organ disease and organ failure is becoming more common today, as advances in surgical techniques and immunosuppression have increased the success rate of this complex procedure, and the aging population creates a greater need for cardiac interventions such as coronary artery bypass surgery combined with liver transplantation.

Common indications for CHLT include:

• Familial amyloidosis.
• Cardiac cirrhosis caused by congenital heart disease or dilated cardiomyopathy.
• Homozygous familial hypercholesterolemia.

The CHLT procedure is challenging for several reasons:

• Hemodynamic instability after transplantation.
• Prolonged organ ischemia during organ preservation.

“We felt that these challenging CHLT cases were perfect situations to benefit from machine perfusion techniques,” said Christopher P. Crome, MD, a transplant surgeon at Mayo Clinic in Jacksonville, Fla. Dr. Crome and his colleagues describe their use of normothermic machine perfusion (NMP) in a case series published in Transplantation Direct.

what's new?

“The ability to pump oxygenated blood to organs outside the body is a relatively new technology in the United States. These devices finally received FDA approval in Q4 2021,” said Dr. Crome, lead author of the paper. “We have adopted machine perfusion technology at Mayo Clinic. This approach allows us to perform CHLT cases that historically many centers have hesitated to perform. Multi-organ transplants are technically complex surgeries, but Mayo Clinic excels in this area thanks to our strong interdisciplinary team.”

In the CHLT procedure, the NMP provides the following functions:

• This allows for longer preservation times, hemodynamic stability after cardiac surgery, and weaning from cardiopulmonary bypass.
• There will be fewer metabolic disturbances due to hepatic reperfusion, such as hyperkalemia, fluid overload, and acidosis, and the burden on the newly transplanted cardiac graft and the revascularized heart will be reduced.

Reducing concerns about cold ischemia time allows for a larger donor pool: “We can harvest organs from further away, which is a big advantage,” says Dr. Crome.

Case series review

In all three cases, surgery was performed safely using hepatic NMP. In addition to liver failure, the patients had heart failure or coronary artery disease. The three surgeries were performed between 2022 and 2023. The patients were male and were 54, 58, and 63 years old at the time of transplantation.

Two patients underwent CHLT surgery and one underwent coronary artery bypass grafting (CABG) and liver transplantation. In the more difficult cases of hepatectomy, there was no need to rush with NMP. In all three cases, no post-reperfusion syndrome (PRS) or early graft dysfunction (ESD) occurred.

The successful use of NMP in three cases led to changes in Mayo Clinic's CHLT protocol. NMP is now routinely used in heart transplants and combined CABG and liver transplants. Mayo Clinic is saving more lives by taking advantage of new technologies early and accepting organ donations from a wider range of donors.

For more information

Das I et al. Use of extracorporeal normothermic machine perfusion in combined heart and liver transplant surgery. Transplant Direct 2024;10(2):e1574.

Refer the patient to Mayo Clinic.