Nir Uriel, MD, MSc, is an authority on heart failure, heart transplantation and clinical management of circulatory assist devices, like the left ventricular assist device, or LVAD. He was recently appointed associate professor of medicine and medical director of the heart failure program at the University of Chicago Medicine.
Uriel, 42, came to the University of Chicago from his former position as an assistant professor of medicine and director of research for the mechanical circulatory support program at Columbia University. Science Life spoke to him recently about his research, what he hopes to accomplish at UChicago, and what he does when he’s not being a physician.
What specific areas of research will you focus on at UChicago?
The field is evolving, but let me start with mechanical circulatory support, or the LVAD, which is a complete shift in the way we think about how to treat heart failure. With this device, we can support people not only until the next stage, which would be a bridge to transplant, but we can support them for as long as they can live, using is as a destination therapy. However, it changes their physiology. We are human beings—we are not supposed to be half-machine. There is an interface between a pump and the body that creates a new physiology. That has been one focus of my research.
I was involved in establishing the understanding the role of the pump in changing the hematological system, not just the heart, and looking at what happens to all of the patients that are supported with continuous flow devices. I was involved in understanding a little bit better how the heart was changing, the change in the body’s metabolic state because of those devices. We are trying to develop algorithms for how to treat this new thing that we now have, a body plus a pump, because now all the things we knew about medicine do not apply. We need to start all over again. What we knew about blood pressure is not applicable to those patients, because those pumps flow at a continuous speed instead of beating like a natural heart. So we don’t have a systolic and diastolic blood pressure of, say, 100 over 80. Instead we have one measurement. What does that mean? So in the last 5 years I have been focusing on developing an algorithm to learn how to understand what changes in those patients, and how to use it.
Because it’s not how our bodies are built. They now have this component of their body that’s a machine pumping blood at one continuous rate.
Exactly, and not only that, it changes the essence of what we are. Instead of a heart rate of 60, you have a pump turning at a set speed of 10,000 revolutions per minute. Our body is used to the normal up and down, beating motions of the heart. The blood vessels for example, if you don’t have the stretch and relax, stretch and relax of a normal heart rhythm, they start to change. So I was involved in a lot of research understanding those changes, and how to manage even the basic stuff like blood pressure for those patients.
What do you have to do to adjust for those changes in the body?
I developed a test where we use ECHO cardiography to visually monitor the heart while we change the speed of the pump. That way we can see the relationship between increasing the speed and what happens inside the heart. But as much as it’s gained popularity in order to set the speed and troubleshoot the device, this test is still limited because it’s two-dimensional. And part of the strength of the University of Chicago is an unbelievable, world-renowned imaging department, from ECHO to MRI, with specific focus on 3D software that is not available anywhere else. Utilizing this test with 3D imaging will take us to a completely different place, and do what we call reverse remodeling to bring the heart back to its natural shape.
What does that allow you to do? Could you somehow recover the heart to a healthy state?
So what is the Holy Grail? First we need to understand why we put in those pumps. Do I want to live with a pump like that? Do you want to live with a pump like that? If we need to, we will do it, but we want our own heart to work. So the Holy Grail in cardiology and heart failure in general is what we call recovery—to recover your own heart, not a transplanted heart, not a machine.
When a heart is going through the process of heart failure, it becomes bigger and bigger and bigger. This is called remodeling. What you do with the pump is suction the blood out and reverse remodel. But how much is the right way? How much do you really need to know not to overshoot it? This is a question. The heart is not only about volume, it’s about shape and power, and how you can create a specific shape to have the best power. At the University of Chicago, the head of the cardiac imaging department, Roberto Lang, MD, is world famous in the field of 3D imaging, and we’re going to utilize both techniques together and see if we can understand how to reverse remodel the heart.
At some point would you be able to take a patient off the pump?
This is the goal, to be able to wean patients from this device and let them live without it. This is something that is already being done in multiple places in the world, but unfortunately not something we can do successfully for the majority of our patients. Eventually we want to find a way to give our patients the best chance to recover their own heart.
But we need to remember that the patient can live a good, healthy life with those devices. Once we develop all those algorithms for how to find the right speed, how to treat their blood pressure, how to deal with bleeding, how the blood system works differently, how to treat diabetes, we can treat those patients better.
What if the device doesn’t work, or they can’t recover?
Then the next step is a heart transplant, which is another focus of my research. As someone who has doing heart transplantion for many years, you look at it as a beautiful miracle that usually results in the majority of patients having an excellent quality of life. However, heart transplant has always, and will always be a boutique medicine. In the United States we do something like 2,000 transplants a year. We still struggle with lack of enough donors, and the number has not changed. We have 6 million people in America with heart failure, but we have only 2,000 transplants a year. This is why there has been greater use of the LVAD pumps.
However, if you can do a transplant, you want to take the person who will be able to live the longest time and with least complications as possible. Another part of my research has been to learn about high-risk patient selection for heart transplants. The first successful transplant was in 1967 by Christiaan Barnard, but in the beginning it was more like an experiment. We didn’t have the understanding about how to deal with the immune system and rejection, so in the beginning the candidates were those who had only heart disease. Today, however, a lot of people survive cancer, but then years down the road because of the chemotherapy and radiation they develop heart failure and need a heart transplant. Should we say no? In the beginning we said no, but now we say yes. When the HIV epidemic started, it was also a no-no for transplants. But now more than one million people in the United States live with HIV and have the same, or a little bit shorter, life expectancy than people that don’t have HIV. However, they develop cardiac disease much more frequently. Should we say no to them too?
What’s the general attitude about those high-risk transplants?
In a study that’s going to be published in the coming Journal of Heart Lung Transplantation, we sent a survey to all the transplant centers in North America asking if they would evaluate a patient with advanced heart failure and HIV. Does this patient have equal access to care? And unfortunately we found dramatic differences between the centers. We learned that actually the majority of the centers say no even without evaluation, and even the others that say yes had never done it. So the thing we will hopefully initiate here is to understand the real need in our HIV population with heart failure, and evaluate how many of those patients we are missing.
Is it common to use the LVAD as a bridge to a heart transplant, or is it meant to be a replacement or destination therapy?
Originally when the LVADs were born, they were meant to be a bridge to transplantation. They were not born to be a destination therapy. One of the cornerstone studies followed patients with very advanced heart failure who either got an LVAD or just had standard medical therapy, and they showed dramatic difference. For the people who had medical care, the 2-year survival was only 8 percent. On the other hand, the patients with the LVAD in this specific study, 25 percent of them survived after 2 years. So not that it’s a lot, but it’s 4 times more.
When the continuous flow LVADs came onto the market, the 2 year survival jumped to 56 percent, and today we can even reach almost 70 percent survival. So that’s the reason we feel comfortable with those devices as a destination therapy.
What’s one big thing you’d like to accomplish in the next 5 years?
In 5 years, I want to see the University of Chicago heart failure program as the preeminent program in the Midwest, and maybe in the country. I think we have all the ingredients to make it happen. We have a phenomenal surgical division here run by Valluvan Jeevanandam, MD, who is one of the best surgeons you can get in the world. We have a very excited and motivated heart failure and transplant cardiology team. I want to see in 5 years that when a patient has heart failure, they wouldn’t blink when they asked, “Should I go to the University of Chicago?” I really believe we have the opportunity and we have the skill set to be one of the leading institutions in heart failure in the world.
What do you do when you’re not being a physician?
Being a physician is not a profession. It is who you are, it never leaves you, however, in order to decompress myself and find myself some quiet time, it’s sports. Sports relax me. I truly believe that both on a medical side and on the Zen aspect of it. Swimming and cycling are my strongest passions, and sometimes I combine those to do triathlons. Sometimes in New York I would go to the MOMA or the Guggenheim just to grab one exhibition, to see one artist take it to the next level, and to see how we can explore to a new horizon. That’s always inspiring and it gives you complete relief and takes you to different places.
But definitely the most important thing is to be with family. You have to have your own time, because you need to compress to let it go. We are dealing with life and death on a daily basis, and when I’m going I home I want to only deal with life, only good things.