For patients undergoing heart transplantation, outcomes are comparable whether or not the donor’s heart was still beating at the time of organ removal, new research shows.
The trick is to get the heart beating again when you have a “nonbeating donor,” said Stephen Large, MBBS, from Papworth Hospital in Cambridge, United Kingdom.
“We’ve got 30 minutes to recover the blood supply to the donor heart from the onset of ischemia — that’s the maximum time,” he told Medscape Medical News.
The use of organs from donors after circulatory-determined death is controversial in many countries, but the supply of organs increases dramatically in places where the practice is accepted, Large explained.
“We already have a 35% increase,” he reported, adding that his team has performed 44 such procedures.
He presented one of three studies on the practice at the International Society for Heart and Lung Transplantation 2018 Scientific Sessions in Nice, France.
In their study, Large and his colleagues compared outcomes in 62 patients — 31 who received a heart after the donor experienced brain death with 31 who received a heart after the donor experienced circulatory death. The hearts were retrieved using direct procurement and perfusion or normothermic regional perfusion followed by continuous machine perfusion.
Rates of survival until hospital discharge were similar in the circulatory-death and brain-death groups (93% vs 97%). Thirty-day survival was 100% in both groups.
Hemodynamic performance — cardiac output, cardiac index, central venous pressure, and pulmonary artery diastolic pressure — was similar in the two groups, as was the need for inotropic support after transplantation.
Median hospital stay was shorter in the circulatory-death than in the brain-death group (20 vs 27 days). However, the need for extracorporeal membrane oxygenation was slightly higher in the circulatory-death group (13% vs 6%).
During another session, 10-year outcomes for patients with obstructive or restrictive chronic lung allograft dysfunction who underwent lung transplantation were presented by Greg Snell, MD, from Alfred Hospital in Melbourne, Australia.
Circulatory-Death Donors in Australia
Whether the donation was made after circulatory death or after brain death, results were similar, Snell reported.
Since the use of organs after circulatory-death was widely adopted, time on the wait list is shorter in Melbourne, he reported during the President’s Debate.
Snell deliberated with Howard Eisen, MD, from the Drexel University College of Medicine and Hahnemann University Hospital in Philadelphia, who, in the spirit of debate, defended the state of Pennsylvania, where transplants after circulatory-death have not been widely adopted.
The number of patients who die on the wait list is much lower in the state of Victoria than in Pennsylvania (4% vs 19%). “Circulatory-determined death donors make up about 41%” of donors in Victoria, whereas “in Pennsylvania, they are 7%,” Snell pointed out.
The use of these donations does not decrease donations after brain death. “If anything, circulatory-determined death creates more talk and more involvement of the donation teams, and you get more donations after brain death as well,” he explained.
Ex vivo perfusion is key to putting the beat back into the heart after circulatory-determined death.
The first human transplantation using a nonischemic method of heart preservation was described during another session by Johan Nilsson, MD, PhD, from Skåne University Hospital in Sweden.
Ex Vivo Perfusion
Nilsson’s team used a mini heart–lung machine that supplied the donor heart with an oxygenated, hyperoncotic, nutrient hormone solution with erythrocytes during transportation. This extends preservation from 4 hours to at least 12, Nilsson reported.
The real advances in transplantation after circulatory death are coming from new technologies, as perfusion machines make their way to the market, said Large.
“We’re expecting an explosion of extracorporeal perfusion machines coming out this year,” he reported. As technology prolongs perfusion times for heart, lung, liver, and kidney, it is likely that the community will become much more “liberal in taking organs.”
“In the United Kingdom, we turn down three of every four hearts offered, the principle reason being poor function,” Large explained. “There are so many areas to explore and improve.”
Large, Snell, and Nilsson have disclosed no relevant financial relationships.
International Society for Heart and Lung Transplantation (ISHLT) 2018 Scientific Sessions: Abstracts 7 and 8, presented April 11, 2018; abstract 314, presented April 14, 2018.
Follow Medscape on Twitter @Medscape and Ingrid Hein @ingridhein
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