Advances in heart transplantation: Normothermic regional perfusion and beyond

 

In a significant effort to modernize the organ transplantation system and increase efficiency and cost effectiveness, Zachary Kon, MD, surgical director of advanced heart failure and cardiac transplantation at Hofstra/Northwell, is spearheading a transformation of how organs are collected, preserved and transplanted. He outlined the current standard of care to organ collection and explained new technology that could improve patient care. 

The current standard of care is "very inefficient, very hectic, very non-collaborative, and it's definitely ripe for improvement," Kon told Cardiovascular Business.

He said new technologies like thoracoabdominal normothermic regional perfusion (NRP), which allow organs to continue to be perfused inside the donor at normal body temperatures, can help expand the time an organ can be used for a transplant. He said the creation of regional transplant teams to harvest organs locally would also enable greater efficiencies and cost savings. 

Current challenges in organ transplantation

Kon highlighted the inefficiencies in the current organ transplant system, describing it as outdated and hectic. When a donor matches a recipient, the transplant center often sends a team, sometimes on a chartered flight, to the donor hospital. This process is costly and carries a risk of the organ being deemed unusable upon evaluation, resulting in a significant loss of time and resources.

Historically, organs have been preserved by cooling them to near-freezing temperatures, usually between 0-4 degrees Celsius, a practice dating back to the inception of organ transplantation. While this method of putting organs on ice in a cooler is simple and effective for short periods, it is less optimal for longer durations and traveling long distances. More advanced preservation methods involve sophisticated pumping systems that maintain a blood-based perfusate, aiming for better temperature control and reducing the organ's ischemic time—the period during which the organ is deprived of blood flow, nutrients and oxygen.

"We are trying to do a better job with preservation. Some of them are very sophisticated pumping systems that will allow preservative or a blood-based perfusion to go through that organ in order to preserve it better. Some of them are cold, some of them are warm, some of them are just targeting better temperatures. So it's really easy to put something on ice, but it's a little bit more sophisticated to get to what probably is the right temperature, which is somewhat above those temperatures that you receive with ice," Kon said. 

Different organs can last longer outside the body awaiting transplant

Kon noted that different organs have different tolerances for how long they can be out of the body without the nutrients the cells need to survive. He said the heart is particularly sensitive and has a very short period for transportno more than four or five hours

However, kidneys can be outside the body for much longer periods beefier suffering damage, as long as 24 to 36 hours. He said this can sometimes be extended further depending on what platform is being used to preserve it. 

"The reason that those time frames are so important is because they directly correlate to the function of the organ when it's actually put in the recipient. Putting it on ice probably is associated with the least tolerance to that period, whether it's short or long," Kon explained. 

Introduction of normothermic regional perfusion for heart transplants

Kon is pioneering the use of NRP, a method that significantly improves organ preservation and recovery outcomes. NRP involves perfusing the donor's organs with warm, oxygenated blood after circulatory death, thereby reducing ischemic injury and improving organ viability. This method not only enhances the quality of the organs, but also increases the number of organs that can be successfully transplanted from a single donor.

Kon is CEO and co-founder of ProCure On Demand, an organ recovery and logistics company that uses NRP. Kon said they wanted to try and revise how the current organ transplant system works to make it more efficient and cost-effective, while at the same time improving patient outcomes by providing more viable organs. 

He said it offers answers to several key issues in the current way organs are explanted and preserved during transport. 

"NRP in the United States predominantly was started as an effort to get a subset of hearts called donation after circulatory death (DCD) hearts. This is a category of donors where historically we've never been able to utilize those hearts in the United States because it's kind of a black box of what happened to them. Did they get injured? Is the heart going to work? So NRP allows us to better evaluate them," Kon explained. 

He said the average yield of organs from DCD historically was 1 to 1.4 organs per donor. But using NRP, he said their experience is now 3 or more organs.

How NRP works to perfuse donor organs

Kon said the transplant recovery teams wait for patient to die and then go into the OR to prepare the body. The organs of interest are then perfused, including the heart, lungs, liver, kidneys, and pancreas. This allows nutrients and blood flow to return, mitigating some of the injury likely that would otherwise happen if you then suddenly just put them on ice and shipped them off, Kon explained. 

The NRP process typically involves the use of a full bypass modified circuit with a reservoir, allowing complete decompression of the venous system and maintaining optimal perfusion pressures. This is preferred over extracorporeal membrane oxygenation (ECMO) due to its ability to maintain low venous pressure and create pulsatile blood flow, which Kon said is believed to be more beneficial for organ health.

This process also allows for in-vivo practical assessments of the heart. "We can actually look at the heart and see how well it squeezes, see what kind of pressure it can produce. We look at an echo while we're doing this to really assess it in a very savvy way that just isn't practical or isn't possible using other methods," he said. 

Competition for organs can impact professionalism

Another big advantage of NRP, Kon said, is the shift toward a more collaborative and professional environment in the donor operating room. Traditionally, multiple transplant teams might work simultaneously, leading to a chaotic and competitive atmosphere. NRP, however, allows a single, highly skilled team to manage the perfusion process and buy more time for the organs. This results in better outcomes for all organs involved, not just the heart, Kon said.

"That lack of collaborative spirit can be associated with uncomfortable situations and certainly worse outcomes for any given organ as people are literally competing to try and utilize and preserve their organ the best they can," Kon explained. He said this can sometimes lead to a lack of professionalism and added stress. 

Another ongoing concern is that the person actually sent to evaluate and explant the organ is often the most junior member on the surgical team. 

"Because of that, they're now in the most stressful possible situation being told to compete with other people to get their organ. So you can imagine that just adds to the confrontation," Kon explained. 

To try to overcome this experience gap, Kon has tried to create a regional or local on-demand marketplace for highly vetted, highly skilled surgeons who can do a better job to evaluate these organs in a collaborative and professional manner. He said creating these types of local experts can help boost their volume of experience to make evaluations and organ removal much faster than teams that only perform a handful of these evaluations each year. 

Future of NRP in DCD organ donation

Kon envisions a future where NRP becomes the standard of care for all DCD organ donations in the United States. He emphasizes the importance of having regional, highly specialized teams to manage the NRP process, rather than hospitals attempting to perform these procedures sporadically. This approach ensures consistency, reliability, and cost-effectiveness, ultimately leading to better patient outcomes and more efficient use of resources, he said.

Dave Fornell is a digital editor with Cardiovascular Business and Radiology Business magazines. He has been covering healthcare for more than 16 years.

Dave Fornell has covered healthcare for more than 17 years, with a focus in cardiology and radiology. Fornell is a 5-time winner of a Jesse H. Neal Award, the most prestigious editorial honors in the field of specialized journalism. The wins included best technical content, best use of social media and best COVID-19 coverage. Fornell was also a three-time Neal finalist for best range of work by a single author. He produces more than 100 editorial videos each year, most of them interviews with key opinion leaders in medicine. He also writes technical articles, covers key trends, conducts video hospital site visits, and is very involved with social media. E-mail: dfornell@innovatehealthcare.com

Around the web

Eleven medical societies have signed on to a consensus statement aimed at standardizing imaging for suspected cardiovascular infections.

Kate Hanneman, MD, explains why many vendors and hospitals want to lower radiology's impact on the environment. "Taking steps to reduce the carbon footprint in healthcare isn’t just an opportunity," she said. "It’s also a responsibility."

Philips introduced a new CT system at ECR aimed at the rapidly growing cardiac CT market, incorporating numerous AI features to optimize workflow and image quality.

Trimed Popup
Trimed Popup