January - April 2008 Issue
Advanced Cardiac Imaging Reveals Heart Problems
Michael Cinquegrani, MDMedical College of Wisconsin Interventional Cardiologist
Interim Director, Cardiovascular Medicine
Named one of the “Best Doctors in America®” 2007 by Best Doctors, Inc.
Cardiac imaging has advanced to the point where physicians can obtain detailed information about the heart in a non-invasive manner. While echocardiography (ultrasound), MRI and CT scans have been used for years, new technology makes these imaging techniques particularly useful for diagnosing heart disease. Dr. Michael Cinquegrani discusses the benefits of these advanced imaging methods.
Q. What new advances exist in cardiac imaging?The imaging techniques we’re using now have been evolving for a long time. Echocardiography, MRI and cardiac CT have been present for some time, but all of them have evolved to the point where they are now very useful tools, particularly when applied to the right patients. Echocardiography, for instance, is very good at looking at the heart’s structure and physiology — how the heart works mechanically; it helps us to find many disorders related to the structure and function of the heart. Now we have 3-D echo, which gives even more structural information about cardiac anatomy. The echo ultrasound probe can be applied from the transthoracic approach (from the top of the chest) as well as the transesophogeal approach (from within the esophagus), and we’ve been working in both of those areas.
Cardiac MRI looks at the heart in a little different way. It also can give information about the structure of the heart, some of which is complementary to what you can get with echo, but it looks more at the tissue of the heart and can help differentiate some things that may be hard to see with echo. One thing we use it for is to look at whether the tissue of the heart is viable, meaning is it permanently damaged from a heart attack?
Cardiac CT has evolved into 64-slice technology, which allows for 64 high-resolution images in a very short period of time. That’s important because the heart is a moving object. We make images of the coronary arteries by using an intravenous injection of X-ray contrast and then doing a very rapid scan of the heart. We can “light up” the coronary arteries and sometimes see them just as well as on a direct angiogram.
Q: What are the benefits of this new technology?Echocardiography is a very important tool in our assessment of patients with various cardiac diseases, both structural heart disease and valve disease. We can also use echocardiography to evaluate coronary artery disease because we can use it during stress testing. Cardiac MR can also be used with stress testing, and we’re going to get some experience with that in the near future. The 64-slice CT can be used in certain situations in which heart catheterization is not a viable option to diagnose a problem.
Q: Do these new techniques and technologies replace other cardiac imaging and procedures?A lot of these tests are complementary. You might get certain information that would be comparable to what you would get from another test, say a CT or an echo. We try to pick the test that’s likely to answer the question we’re asking without having to use every imaging method at our disposal. It’s our responsibility to determine the right test for the right patient.
Q. Do these new technologies lead to better treatment options and better patient outcomes?Before you can decide on a course of treatment, you need to make an accurate diagnosis. Getting a proper diagnosis allows you to follow the most appropriate treatment path, which, in turn, will hopefully lead to the best outcome for the patient. Today’s imaging is at a level where, with any of these methods, you can see things in the heart that would not have been possible to see even 15 years ago.
Q: There are a lot of ads for $199 heart scans. Is this a good idea?Those scans are actually CT scans of the chest that look at the amount of calcium in the coronary arteries. This can tell you if you have atherosclerosis, or hardening of the arteries. It doesn’t tell you if you have tight blockages or if you’re going to have a heart attack. Only in a very broad sense does it say, yes, you’re at risk for those problems. For a lot of people, you know by their basic risk factor profile whether they’re likely to have coronary artery disease. You can almost predict the results of the test based on the profile. So for a lot of people, these scans don’t add that much more information. People who are interested in a heart scan should really have a conversation with their general physician regarding the potential value.
Source: Every Day
Date: Jan - April 2008 Issue