Newswise &emdash; Medical College of Wisconsin physicians at Froedtert Hospital are using the most powerful medical CT scanner in the world to research the potential for noninvasive approaches to diagnosing and treating heart disease. The initial results of the study are already changing the way cardiac medicine is practiced.
A team led by Dennis Foley, M.D., professor of radiology at the Medical College, and chief of digital imaging at Froedtert Hospital, and David Marks, M.D., associate professor of medicine at the Medical College, and director of the cardiac catheterization laboratory at Froedtert Hospital, is using the LightSpeed volume computed tomography (VCT) scanner for the study, which will involve about 150 patients. The world’s first LightSpeed was manufactured by GE Healthcare (a business unit of General Electric Company) and installed at Froedtert Hospital in June 2004.
The Lightspeed can scan the heart in about five heartbeats, less than 10 seconds. Previous generations of CT scanners showed 16 or 32 pictures or “slices” per scan; the newest Lightspeed VCT produces 64 slices that are obtained in synchrony with the patient’s heart beat in 350 milliseconds and results in a tremendously sharp three-dimensional image.
“In the cardiac arena, this unprecedented speed allows us to capture an outstanding picture of a patient’s beating heart without having the patient undergo an angiogram. This truly has the potential to transform the way doctors are able to diagnose and treat heart disease,” says Dr. Foley.
Angiograms generally take about 45 minutes. A patient is sedated, a small catheter is inserted into a patient’s blood vessels, and dye is injected that makes the vessels visible on x-rays. With the new procedure, in just a few minutes with no sedation, a patient can have a single scan that the doctor can use to assess three major cardiac dangers: clogged arteries, a torn aorta or pulmonary embolism.
In the study, patients will have both an angiogram and a Lightspeed VCT scan, and clinicians will compare the results. They will in essence be their own controls. Information on a patient’s heart will first be gathered using the VCT and compared to information received from the cardiac catheterization, the gold standard with which diagnostic and treatment decision are made.
“We have a new technology that’s very exciting, but we want to be sure it’s being used in the right way. First, we’re going to review the Lightspeed’s accuracy to be sure it is comparable to an angiogram. Then we’re going to look at its long-term health care and economic implications. With the enhanced diagnostic information there may be a tendency to suggest more procedures. Over the course of a year, we’ll follow these patients and find out what’s happened to them,” says Dr. Marks.
In addition, the results of the study will guide clinicians in the use of the technique as a stand along diagnostic tool. It may also help in the diagnostic evaluation of emergency patients.
GE Healthcare has worked for more than two decades with Medical College physicians at Froedtert Hospital to test prototypes of their new technology.
