Jul 17, 2018
Richard Channick, MD discusses pulmonary embolism or blood clots in the lungs, and how they can progress to CTEPH (Chronic Thromboembolic Pulmonary Hypertension).
I'm Rich Channick. I'm from Mass General Hospital in Boston, and I run the pulmonary hypertension program there.
Today we're going to talk about pulmonary embolism or blood clots in the lungs, and how they can progress to chronic thromboembolic pulmonary hypertension, or what we call CTEPH.
CTEPH is a very important cause of pulmonary hypertension because it is a curable form of PH. Because of that, physicians really don't want to miss this diagnosis and patients want to be very aware of what are the signs and symptoms of CTEPH, but it all starts with an acute pulmonary embolism. Acute pulmonary embolism or blood clots that go to your lungs are very, very common. They happen in over half a million, maybe even a million people in the U.S. a year. Most people who have an acute pulmonary embolism will get over it, and the body will dissolve the clot and the symptoms will go away, but there is a percentage of patients that won't happen in, and they'll start to develop more shortness of breath. They just don't feel the same afterwards.
In patients like that, where they don't get over the acute pulmonary embolism and are still symptomatic, one needs to consider CTEPH. It turns out that even though that's how we'd like it to be, many times this diagnosis is missed. We've actually looked at this and found that there's about a two to three year delay in diagnosis between when a patient first develops symptoms and when they get the proper diagnosis of CTEPH. Many of these patients, at least half of them have a clear history of an acute pulmonary embolism in the past, but the physician and even the patient didn't realize that this could be a problem, CTEPH. So it becomes very important to try to raise awareness for the diagnosis.
We looked at this in a study a couple years ago where we looked at insurance claims for different diagnoses. What we found was very scary, actually. Of all the patients who were diagnosed with pulmonary embolism, at least in an insurance claim, that at two years eight to ten percent of those patients had a subsequent diagnosis of pulmonary hypertension in an insurance claim. Now, there could've been other causes of pulmonary hypertension, but it could've been CTEPH. When we looked at the testing that was ordered for those patients, whereas the testing you're supposed to get is a V/Q scan of the lungs, only about less than 10% of patients had gotten any kind of scans. So the physicians were not ordering the tests looking for what the patient could have. This doesn't tell us for sure how often the problem is occurring, but it certainly suggests that it may be a much more important problem than we're aware of. It's really critical for patients to understand this.
We've had many patients over the years that it was the patient that came to the doctor saying, "I think this is what I have." They had read or heard about CTEPH. They had been told maybe by other doctors that there was nothing wrong with them or they had asthma. Some of the usual misdiagnoses that patients get, but they saw something or heard something about CTEPH. They remembered they had had a pulmonary embolism in the past. They're like, "I have this," and they turned out to have operable CTEPH, which was then cured with surgery.
The other aspect of the disease that's becoming increasingly important is that there actually are other treatment options besides surgery for some patients with CTEPH. Whereas in the past, you either had to open heart surgery, which again can be curative, or there was nothing that could be done with inoperable disease or who had other medical problems that prevented them from going through surgery and anesthesia.
But now there are two important advances. There's medication. There's one medication, which is FDA approved for patients with CTEPH who are inoperable or who still have PH after surgery, and then there are other drugs, we think, that likely will be approved for the same kind of indication. Then lastly, there's a new procedure called balloon angioplasty in which the vessels can be opened up with balloons, and that has been shown to really, in some cases, cure or markedly improve the pulmonary hypertension, and balloon pulmonary angioplasty is becoming increasingly popular as an alternative treatment for some patients with CTEPH.
Balloon pulmonary angioplasty has been around for a while, but it hadn't been done for quite a while. There was a report about 15 years ago on some CTEPH patients undergoing it, but there were a lot of complications, severe ones, so people stopped doing it. The Japanese, several groups, published recently then a paper showing a modification of the technique to make it safer. With their experience, other centers started doing it. It's still relatively uncommon and certainly it should still be done at expert centers in CTEPH, but several expert centers in the US, including my center, are doing these regularly and successfully. Now, we need to find out what the long-term effects are, whether it's sustainable. We'll clearly need more long-term data, but I think definitely there's a future for this procedure.
An important question is what is the role of medical therapy maybe with balloon angioplasty? That's actually an area of active study. We certainly have many patients who undergo this procedure who are also on medical therapy for CTEPH. Whether that adds to the procedure and you get more of a benefit is being looked at, but certainly that's actually a fairly common scenario.
I'm Rich Channick, and I'm aware that I'm rare.
Learn more about pulmonary hypertension at www.phaware365.global. Never miss an episode with the phaware® podcast app. Follow us @phaware on facebook, twitter, instagram, youtube & linkedin Engage for a cure: www.phaware.global/donate #phaware #phawareMD