Papworth Hospital pioneers non-beating heart transplants that could save many more lives
PUBLISHED: 09:17 16 December 2017 | UPDATED: 10:20 16 December 2017
Iliffe Media Ltd
Surgeon Pedro Catarino explains how a new technique could help meet demand for more organs
On December 3, 1967, the world’s first successful human heart transplant was performed in Cape Town, South Africa.
Fifty years on, a study has supported a technique pioneered by surgeons at Papworth Hospital using non-beating hearts – which could help to significantly increase the number of transplants carried out there and around the world.
“I think we could double the numbers here within two years,” said Pedro Catarino, clinical director of transplantation and consultant cardiothoracic and transplant surgeon at Papworth Hospital.
Since Sir Terence English completed the UK’s first successful heart transplant at Papworth in 1979, the hospital has completed 1,481 such operations.
But the number of transplants has been falling as improvements in medical science and road safety reduce the availability of donor organs.
“The normal heart donor is somebody who is brain dead,” Mr Catarino told the Cambridge Independent. “They are patients on intensive care who have had a head injury. They are legally dead but their heart is still beating.
“We take them into an operating theatre. When all the organ retrieval teams are ready we deliberately stop the heart. We stop the blood flow and inject the heart with a preservation solution which stops it being damaged by the period when it does not have a blood supply. That gives us a good four hours to take the heart and put it in the recipient.”
Until recently, surgeons have only been able to use such donors following the diagnosis of brain death (DBD).
But in March 2015, consultant cardiothoracic surgeon Stephen Large led a Papworth team as it performed Europe’s first transplant using a heart from a circulatory determined dead donor (DCD) – a person confirmed dead because their heart had stopped beating.
Since then, Papworth has carried out 37 such procedures, increasing the number of heart transplants carried out there by a third.
“With DCD, these patients are not brain dead but are very ill. They are almost always in intensive care. They have had treatment and the team have realised it has become futile. There is a discussion with the family, usually after quite a few days of treatment,” said Mr Catarino.
“If they decide to withdraw treatment, they let the various organ retrieval teams know. We send people to the hospital. The patient dies over a period of perhaps 30 minutes to two hours, because their heart stops.
“They are diagnosed as dead the way most people are – they have no pulse, no heartbeat, no heart sounds.
“Then there’s a stand-off period, which in the UK is five minutes. You wait that time, then reconfirm that there is no pulse or heartbeat. All the organs will have had no blood supply.
“This is not a ‘prepared’ situation, unlike with a brain-dead donor. These patients are warm so their organs decay during that period. Different organs have different tolerances.
“It takes at least 30 minutes to get the heart out and restart the blood supply. You have a half-hour where it has no blood or oxygen and we thought they would never really work because they would be too damaged. But what the Papworth research programme showed was that these hearts really do work. The heart has a better tolerance than the liver for this period of warm ischaemia – when the heart is warm but has no blood or oxygen.
“It relies on you taking the heart out and putting it on a pump. The blood is taken from the donor themselves and is pumped around an oxygenator and into the heart, which is resuscitated over a period of a couple of hours. We can use that heart for transplantation.”
After the heart is removed from a donor, it is placed into a Transmedia Organ Care System (OCS) – sometimes called the ‘heart-in-a-box’ – for transportation.
“It’s warm and it has blood flowing through the coronary artery. You can watch it beat,” said Mr Catarino. “The machine is enclosed and has a sterile case. It’s raced with blue lights to Papworth. During the time it’s travelling, we are preparing the recipient. They go to theatre, have anaesthetic and monitoring lines and their heart is removed.
“They are put on a heart-lung machine and are ready when the device arrives at Papworth. We take the heart off the machine, sew it in and there’s another 30-35 minutes where it doesn’t have a blood supply between going from the recipient to being reperfused in the recipient, but we’ll cool it and inject preservative solution to cover that time.”
It was a discovery by Mr Large back in 2006 that paved the way for this new approach.
“The breakthrough came when he saw something called auto reanimation, where the heart stops for a while and then starts beating again,” explained Mr Catarino.
“He thought if he could perfuse the heart that would encourage it to be reanimated and he did this in a donor in 2006.
“The donor’s heart wasn’t suitable for transplantation and the family agreed for him to do it.”
When the donor’s heart stopped from natural causes, Mr Large forced blood to flow back through it and managed to reanimate it.
“He measured the pressure in the heart and how much work it could do and saw it was generating enough power to be used in a clinical transplant. After that, Papworth started research into this,” said Mr Catarino.
A new research paper reveals the survival rate and recovery of 28 DCD recipients were comparable to those of matched DBD recipients – who would have been eligible for DCD – over a 25-month period. One-year survival rates for both sets of patients were 92 per cent.
Mr Large welcomed the results.
He said: “It’s great news. The results show the DCD procedure is at least as good as conventional DBD heart transplantation. We know that 56 per cent of people on the waiting list don’t get transplanted because there are not enough donors. It’s a stark illustration of just how vital these extra donor organs are.”
In addition to the 37 DCD transplants at Papworth, Harefield in London and Wythenshawe Hospital in Manchester have carried out small numbers of the operations, while St Vincent’s Hospital in Sydney, Australia, also uses the technique.
Mr Catarino added: “I think it will become more widespread, not only in the UK but internationally. Many centres have approached us to help.”
The process has been in use with lungs, kidneys and livers for years.
“No-one thought that if you were declared dead because your heart had stopped that the organ would be suitable to keep somebody else alive,” said Mr Catarino, who carries out about 12-15 heart transplants a year.
Heart transplantation has evolved significantly since the first procedure. Until the early 1980s, donors had to be in the same hospital as the recipient.
“Now you wouldn’t imagine moving the donor,” said Mr Catarino. “We have better organ preservation, better ways of looking after the heart. It means we can reach a donor heart in most places in the UK and get it back and transplanted within the four hours we have to do it.
“Our biggest problem is the availability of donors, and then obtaining family consent. Around 43 per cent of families say no – even when the would-be donor is on the donor register.”
He expects further development of the DCD technique in the coming years, with more work to improve the heart’s tolerance to the period when it has no blood supply, so more organs can be used.
“Five years ago, I thought heart transplants were going to be historical and be replaced by something else,” he said. “But the various artificial heart pumps, which have been around for many years and have been through several generations, are still way behind heart transplantation.
“They are behind on survival statistics and also on the quality of life for people who get them.
“If you have heart failure, you will get the best results by having a heart transplant. You can run your local 10k. We’ve had patients who have gone to the Arctic Circle or climbed Kilimanjaro. You don’t get that with mechanical devices. And things like stem cells are still way off.
“So I think we are looking at heart transplants as the number one treatment for heart failure for at least another decade.”
Heart transplants ‘have become procedural’
Professor John Wallwork, chairman of Papworth Hospital Foundation Trust, who performed Europe’s first successful heart-lung transplant at Papworth in 1984, said heart transplantation had become almost routine. Now, 80 per cent of patients are expected to live for at least five years.
“When the first heart transplants were done the patients became celebrities,” he said. “The nice thing now is that people can have the operation and then go back to living their normal lives. In a way, the operation itself has become procedural; the focus is keeping people alive for many years, and that’s the way we run the transplant service at Papworth.”
The DCD approach will give many more people a chance at life, he added.
“Donor numbers are falling – mainly because of improvements in road safety and better management of health conditions like high blood pressure,” he
“There used to be around 400 heart transplants carried out every year in the UK. Last year there were 178. The DCD procedure has managed to take hearts from donors we wouldn’t normally have used and offer many more people a second chance at life.”
29 - the number of people currently on Papworth’s active heart transplant waiting list
54 - the average age of a patient on Papworth’s active heart transplant waiting list
87 the percentage of men on Papworth’s active heart transplant waiting list
6 - the age of the youngest ever heart transplant patient at Papworth
70 - the age of the oldest ever heart transplant patient at Papworth
47 - the number of heart transplant operations at Papworth in the 2016/2017 financial year
1,481 - the total number of heart transplants at Papworth to date
37 - the number of DCD heart transplants at Papworth to date
178 - the number of heart transplants carried out in the UK last year