Computerized Scan Detects Heart Disease
TUESDAY April 28, 2009 -- A computerized chest scan successfully singles out those people coming into emergency rooms with chest pains who have serious heart disease, a new study indicates.
Of the 368 people in the study, computed tomography angiography (CTA) was 100 percent effective in identifying the 31 who actually had acute coronary syndrome, according to a report in the April 28 issue of the Journal of the American College of Cardiology. None of the people who were cleared by the scans had a coronary event in the following six months.
"The study really shows that in this population, CTA is useful and would be good to tremendously improve triage of these patients," said study author Dr. Udo Hoffman, an associate professor of radiology at Harvard Medical School and Massachusetts General Hospital.
Triage -- identifying who needs immediate care and who doesn't -- is of increasing importance as hospitals try to cut medical costs. Many people who come to emergency rooms with chest pains now undergo a series of tests, often being hospitalized. Even though CTA is expensive, at about $1,500 a test, it could save money by eliminating unnecessary hospitalization.
The people in the study were at relatively high risk of coronary disease. Yet the CTA scan, which gives a 64-slice image of the heart, found that most of them did not require immediate hospitalization and further testing.
The case for using CTA for triage in suspected heart disease is not completed, Hoffman said. "The next step is a randomized trial," he said. "We have to look at physician behavior, how physicians will adopt this technology."
But, he added, "I think in places where there is a lot of expertise, there may be enough evidence to use it."
That certainly is true at the University of Pennsylvania, said Dr. Judd Hollander, clinical research director of emergency medicine, and a member of a group that has done a number of studies on CTA in triage of suspected coronary disease.
"We use it a ton in our institution, and I think clinical use of it is growing," Hollander said. "Use is growing faster than data, because all the early reports look great."
But the key to success is using the scan in appropriate cases, Hollander said. "If you apply it to everyone who walks in the door with a tinge of chest pain, it might actually increase risk," he said, which comes in part from the radiation exposure necessary for CTA.
"I would use it on people who, in a physician's judgment, are at high enough risk to warrant admission into the hospital," Hollander said. "With CTA, you switch testing from the hospital tomorrow to the emergency room today, and save that admission."
A report on the University of Pennsylvania's use of the scans in the emergency room, published last month, shows that "real costs from CTA are cheaper than doing other tests," he said.
A randomized trial would provide final proof of CTA effectiveness, Hollander and Hoffman agreed. Such a trial has been started at the University of Pennsylvania, Hollander said. But even before results of a randomized trial are available, "CTA is being used for triage in a lot of places, given the pressure to control health-care costs today," Hollander said.
The why and how of CTA are explained by the Cleveland Clinic.
Posted: April 2009