CT Heart Scans Cut X-ray Dose To Patients, Study Says

Heart scans that detect blocked arteries can bea year in 1980, according to a 2007 review in the New
performed with half the amount of radiation exposureEngland Journal of Medicine. About 800,000 of the
to patients to make them safer, according toprocedures in 2006 were heart scans, according to a
Bloomberg news.recent study in Health Physics.
The Michigan study measured the radiation dose fromHigh cumulative doses of medical radiation may raise
heart CT scans of 4,862 patients in 15 hospitals fromthe risk of cancer, though researchers aren’t
July 2007 to April 2008. A quality control programcertain how much radiation may cause malignancy,
lowered the median radiation dose -- expressed insaid Gilbert Raff, the lead author of today’s study.
units known as millisieverts --to 10 from 21, according toResearch in the Feb. 4 issue of the Journal of the
a study in the Journal of the American MedicalAmerican Medical Association estimated radiation from
Association. The full body scans produced good qualitya cardiac CT heart scan equals 600 chest x-rays. At
diagnostic images, the study authors said.the outset of the study, scans delivered a dose of
Use of computed tomography, or CT, scans of allradiation equal to what a person would get from
organs is growing rapidly and accounts for half of theseven years of background radiation from the sun and
collective dose of medical radiation U.S. patientsfrom elements in the earth including radon.
received in 2006, the American Heart Association saidRadiation dosages were reduced by lowering the tube
in a February statement. The association urgedvoltage of the scanning equipment, and slowing the
doctors to keep doses of radiation from heart scanspatients’ heart rate with beta blocker drugs an hour
“as low as reasonably achievable,” and to usebefore the procedure. Cardiac CT imaging is gaining
them appropriately.popularity because of its efficiency and economy, a
Cardiologists use CT heart scans to detect arterytop Los Angeles cardiologist says. CT scans are
blockages that may lead to heart attacks and otherfaster, less invasive and cheaper than some older
problems. Cardiovascular disease, the top cause ofimaging procedures, costing about $750 or one-tenth
death in the industrialized world, led to 864,480 deathsthe cost of a cardiac catheterization, it is estimated.
in the U.S. in 2005, according to the heart association.The research was funded by Blue Cross/Blue Shield
The number of CT tests in the U.S. surged to anof Michigan.
estimated 62 million a year in 2006 from about 3 million