Transcription:
Advanced Imaging Options for Heart Disease

Melanie Cole (Host): New advances in heart imaging can help doctors better identify heart disease. My guest is Dr. Jamie Bourque. He's a cardiologist at UVA Health System. Welcome to the show, Dr. Borque. Tell us what are some of the advanced imaging options available at UVA to identify heart disease.

Dr. Jamie Bourque (Guest): Well, thank you very much for having me. We have several advanced imaging options available now, including Cardiac Magnetic Resonance Imaging or Cardiac MRI, which gives very detailed images of the structure and function of the heart and has some additional features, such as scar imaging that is particularly useful; Cardiac Computed Tomography which allows us to look at the coronary arteries in a non-invasive fashion, without actually having to put a catheter in the body. But the one that I'm particularly excited about and that we recently started using is an advanced form of stress-test imaging called Cardiac Positron Emission Tomography, or Cardiac PET for short.

Melanie: And what exactly is that? How does it differ from the standard imaging?

Dr. Bourque: Cardiac PET stress testing allows us to more accurately diagnose chest pain that we think is due to coronary artery disease more quickly that our standard stress imaging and also with less radiation. Those are all advantages, but the most exciting feature is its ability to image the microvasculature—that is, the small blood vessels that supply the heart. Using this technique, we can identify the cause of chest pain in patients with convincing symptom but who have a negative workup, including a cardiac cauterization. These patients have previously been told there is nothing wrong with their heart, but we now know that sometimes that is not the case. They may have coronary microvascular dysfunction, and this test allows us to look for that.

Melanie: So it gives you a better view of those micro-vessels that we didn't have before.

Dr. Bourque: Yeah. Previously, there was no way to actually assess those vessels, and this is now an option that is available to us.

Melanie: So who benefits most from these new imaging techniques?

Dr. Bourque: Again, patients who have a negative cardiac workup previously but may have continued symptoms, or who had a stress test that was previously equivocal, as in they weren't quite sure whether it was positive or negative, which can sometimes happen with our stress testing. Those sorts of patients particularly benefit from Cardiac PET Imaging. However, because of its improved diagnostic accuracy in patients who have multi-vessel disease, it's also very useful in patients who have diabetes and kidney disease, as well as patients who may carry a little more weight.

Melanie: So in the Cardiac PET stress test, are there limiting factors as in a regular stress test, where maybe the quadriceps start to burn early, or the person can't keep up with the treadmill? Are there those limiting factors, or have those been removed?

Dr. Bourque: It's a good question. Unfortunately, the current tracers available don't allow us to use exercise for stress. By the time the patient got on the table after exercising, the tracer would already be gone, which is good because it means low radiation for the patient, but it's unfortunate we can't use exercise. There are some imaging tracers in the research pipeline that will allow exercise stress, but for the moment, what we do is we give a medication that dilates the blood vessels, and that simulates stress on the heart. It's very safe but also allows us to stress the heart without actually having them walk on a treadmill.

Melanie: So Dr. Bourque, what would you recommend for heart imaging exams that patients should undergo routinely, and how often?

Dr. Bourque: It turns out that most of our cardiac imaging really should only be done when a patient is symptomatic. So they may have chest pain or shortness of breath. There are very specific instances where noninvasive imaging may be helpful, such as someone with a very significant family history in multiple cardiac risk factors, or someone who is particularly high risk and plans to undergo non-cardiac surgery. But for most patients, we actually would wait to do any imaging until they had symptoms. This has really been an advance in our field. Cardiac imaging is something that has been overused to the significant expense of patients and insurance companies, and then, also, significant expenditures to patient time and effort. For the most part, patients should really be symptomatic before undergoing these tests.

Melanie: Are there different rules for men versus women?

Dr. Bourque: Basically, men do have a higher risk of coronary disease. However, that difference has been shrinking, partly due to the sort of rise of obesity, increased tobacco use in women. While that might have been the case in the past, it's less true now.

Melanie: If someone is experiencing chest pain, shortness of breath, how do you determine? Do you go right into testing? How do you determine whether this is anxiety? Because we're a very stressed out society these days, Dr. Bourque, and sometimes those symptoms can be associated with a number of different other conditions.

Dr. Bourque: Absolutely. There's no question that both chest pain and shortness of breath can be due to non-cardiac reasons, or even to cardiac reasons other than decreased blood flow to the heart. The initial screen that we do is with a careful history in physical. And oftentimes, in talking with patients and finding out when they have their symptoms and the quality of their symptoms we're able to make a determination, "Well, that chest pain that you get when you're just sitting still on the couch and it's worse after a fatty meal, that's probably not coronary disease, whereas chest pain or shortness of breath that comes on three minutes or every time you go up a flight of stairs, or every time you walk up a hill, causing you to sweat and pant and have to stop at the top and resting makes it better, that's very concerning symptomatology."

Melanie: What about other imaging tests that have been used previously, like carotid ultrasounds or looking at cholesterol levels, plaques in arteries? Are we still using these, even CRP?

Dr. Bourque: Those are all good methods for risk stratification for patients. Again, those sorts of testing are probably better, as you were saying before, for the asymptomatic patient, where we may want to look at someone who has a family history, or who has multiple cardiovascular risk factors and do plaque imaging. Or actually, the most effective method we have right now is calcium scoring, which is a non-invasive cardiovascular imaging test, relatively inexpensive. We do offer that at UVA. But usually, looking at blood pressure, blood glucose, cholesterol, all of the standard cardiac risk factors gives us a pretty good idea of who to test. CRP can be used in patients where you sort of have a borderline, "Should we treat this patient or not?" after looking at their risk factors? The CRP, Calcium Scoring, which we do offer, Carotid Intima-Medial Thickness Measurement, but calcium scoring is probably a better method.

Melanie: Why should patients choose patients choose UVA for their heart care?

Dr. Bourque: I'm biased, but I do believe that UVA is an excellent choice for anyone who's looking for compassionate care and for a comprehensive evaluation of their heart by highly trained physicians using the latest tools that are available anywhere. I believe that our up-to-date knowledge and our cutting-edge diagnostic testing and the treatments that we have available make us the clear choice for cardiac care.

Melanie: Dr. Bourque, give us your best advice in the last minute for preventing heart disease, and maybe then, we don't have to come see you.

Dr. Bourque: Absolutely. I think that the best thing that folks can do to prevent heart disease are to watch their risk factors. Get an annual physical, monitor the blood pressure, monitor cholesterol, watch your diet. A Mediterranean diet, we know now, is probably the best way to go. Keep one's weight down, keep from becoming overweight. And probably, most importantly—and I know you like to hear this as an exercise physiologist—we need to get out and exercise more. And I think if patients do all of those things...

Melanie: Thank you so much. If they do all of those things, then maybe they can help to prevent heart disease in this Heart Health Month. You're listening to UVA Health System Radio. For more information, you can go to uvahealth.com. This is Melanie Cole. Thank you so much for listening.