Richard Channick, MD - phaware® interview 547

The Silent Rise of Chronic Pulmonary Embolism and the Tech That’s Changing Everything

From portable ECMO to catheter breakthroughs, the treatment of pulmonary embolism has come a long way. Dr. Richard Channick takes us behind the scenes of cutting-edge interventions and shares the empowering truth: even community hospitals now have lifelines to expert centers. The care you need might be closer than you think.

Hello, I'm Rich Channick. I'm Professor of Medicine at UCLA Medical Center and Co-Director of the Pulmonary Vascular Disease Program at UCLA. I've been there for the last six and a half years, but have been involved with pulmonary hypertension for over 30 years from my fellowship in the '80s onward. I've gotten to see all the evolution and changes that have occurred in this exciting field.

Today, I'd like to talk to you about a session at a recent CHEST meeting in Boston, where we discussed, among other things, chronic thromboembolic disease and the best treatment for those patients. These are people who've had a blood clot or pulmonary embolism as we call it, but for some reason those blood clots have not gone away and they become chronic or more like scar tissue inside the arteries of the lungs. Depending on how much clot there is and how the patient is doing, there may be intervention needed.

The good news is that they're very effective treatments for patients with chronic thromboembolic disease. Those treatments have been well known. There's a surgery called a pulmonary thromboendarterectomy or PTE surgery that can be curative. There's catheter procedures. There's even medication. What about patients who have some blood clots but they don't have pulmonary hypertension? So they have these chronic blood clots, but it's not enough to cause elevated resting pulmonary pressures. That's an interesting area, because those patients may have symptoms and they may be limited by that chronic blood clot, but it's not to a severity where they have right heart enlargement or really high pressures. But still, there may be some patients that treatment is warranted. That's kind of what we discussed.

What would be the reason to do a surgery for instance on somebody who had chronic thromboemboli with no pulmonary hypertension? There's some ways to look at that using some more sophisticated testing like cardiopulmonary exercise testing, where a patient gets on a bicycle and you see how far the person can pedal and measure a bunch of things when you collect the gas, if they're wearing a mask and whatnot. Those are ways to evaluate patients to determine if for instance surgery would be an option for somebody who has chronic thromboembolic disease without pulmonary hypertension.

It's also important because these are more common than we think. CTEPH as we call it, chronic thromboembolic pulmonary hypertension, is relatively rare, but CTED, or chronic thromboembolic disease, is probably quite a bit more common. It also points out something very important that I've always pushed is that after a patient has an acute pulmonary embolism and close to a million people by the way have pulmonary emboli in a year in the US, there needs to be a very structured follow-up six, eight weeks after that acute pulmonary embolism to really evaluate has the patient returned to baseline, are they fully recovered, or do they have any persistent symptoms? Those are patients you're going to want to follow a lot more closely.

A lot of what I do is to really develop a system for systematic follow-up after an acute pulmonary embolism. The system from when I first started doing this, which was much more haphazard for following patients after acute pulmonary embolism, has really been revolutionized. I was fortunate enough, when I was in Boston in about 2011 at Mass General Hospital to develop something called PERT or pulmonary embolism response team. This was something that we came up with to try to do just that, organize how patients are not just managed acutely, but followed up after the acute pulmonary embolism; to have a multidisciplinary team and an organized process for treating these patients optimally.

PERT concept is something that's really taken off around the world, actually, where these teams are in hundreds and hundreds of hospitals. We have a consortium of PERT teams that we meet every year. It's really kind of been a revolutionary change since how I remember it in the '80s to where we are now, which is very satisfying.

One of the changes or evolutions we've seen in pulmonary embolism is really the availability and application of advanced technologies. I mentioned surgery, the catheter procedures, even medication. I think that this is an example where the technology has really made a big difference. For instance, ECMO or extracorporeal membrane oxygenator, it's almost like a heart-lung machine, which has been around for many decades, but with improvements in technology it's been made more portable, lower complication rate. Now, we're using it acutely to treat life-threatening pulmonary emboli, not uncommonly. That was another thing we talked about is what are the indications? When would we put a patient on an ECMO machine in the setting of pulmonary embolism and how we would do that?

It's not available at every hospital. So, like a lot of high-level technologies, small community hospitals may not have access to it, whereas big hospitals do. Actually, that's another advantage or value of the whole PERT concept is that a hospital that may be smaller, a community hospital, may in many cases have a relationship with a large PERT center. We've set up this sort of hub-and-spoke model and actually now have just initiated an accreditation program for the pulmonary embolism response team consortium. Similarly, what we did with PHA many years ago, (The Pulmonary Hypertension Association), where we can look at different centers and seeing what they can offer patients for pulmonary emboli and do they have a relationship with surrounding hospital? Things like transfer of care for patients. So, if a patient has a big pulmonary embolism and is close to a small hospital and it's a life-threatening situation, there's a mechanism for transferring those patients to larger places.

The centers of expertise in pulmonary embolism in terms of the ability to perform open-heart surgery to remove these blood clots has really expanded over the years. We do have to distinguish the acute blood clots from chronic blood clots. CTEPH for chronic blood clots is a little more difficult, because these clots are kind of grown into the wall of the vessel. You really need a surgeon with a lot of experience and that's why, for instance, UC San Diego where the surgery is pioneered, still remains still the very largest program by far, but there definitely are now programs around the country that have developed that expertise. I think that that's really a good thing because back in the day, and I was in San Diego for over 20 years, patients aren't always in a position to fly across the country to have a procedure. They're too sick and they don't have the means, whatever.

It's really been critical that these regional centers developed. We built one in Boston when I was there, which served a huge need in people in the New England area, for instance, to have a center. Now, it's all around the country I would say. 10, 12, maybe, at least, regional centers.

Pulmonary emboli can present in a number of ways. Certainly shortness of breath, chest pain, lightheadedness. You may think about a pulmonary embolism. There's certain risk factors. Blood clots form usually in the legs and then they break off and go to the lungs. Things that may make it a risk to develop a blood clot in the leg like prolonged immobility. So, you're lying in bed because you're sick or you just had a recent surgery. There are certain things like orthopedic procedure, specifically, where you have a very high risk of getting a blood clot in the leg. Most of the time, orthopedic surgeons, they'll give you what we call prophylactic medications, either shots or pills, to prevent blood clots from developing. Certainly, you want to make sure that your doctor has addressed that and hasn't overlooked it for instance.

You need to really be sure that if you have orthopedic surgery or any prolonged immobility, you should at least discuss having blood thinners to prevent blood clots. Certainly, when there are symptoms that develop; swollen leg, the things I mentioned, you need to seek medical attention, because, not to scare people, but the mantra is that if a patient makes it to the hospital with acute pulmonary embolism, they have a very high likelihood of doing fine, of surviving.

It's the next one that you worry about. You don't want to sit at home thinking you're going to get better and then the next one happens, because then that can be a very bad situation. If you have these symptoms and they're not easily explained, you should go to the hospital.

My name is Dr. Richard Channick and I'm aware that my patients are rare.

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