(Ivanhoe Newswire) – Researchers may be able to predict future severe
heart attacks in patients with known, stable coronary artery disease (CAD)
using coronary calcium scoring, according to a new study.
"The amount of calcium in the coronary vessels, as measured by CT, is of
high predictive value for subsequent serious or fatal heart attack in these
patients, independent of the patient's age, sex and other coronary risk
factors," the study's lead author, Marcus Hacker, M.D., of the Department of
Nuclear Medicine, leader of the research unit for nuclear cardiology and
assistant medical director at Ludwig Maximilians University in Munich,
Germany was quoted as saying.
CAD, the most common type of heart disease, is the leading cause of death in
the U.S. for both men and women, killing more than 500,000 Americans each
year. CAD is a condition in which plaque, consisting of cholesterol,
calcium, fat and other substances, builds up inside the arteries that supply
blood to the heart. When plaque builds up in the coronary arteries, blood
flow to the heart is reduced and may lead to arrhythmia, heart attack or
heart failure.
Single photon emission computed tomography (SPECT) myocardial perfusion
imaging is a diagnostic procedure that provides excellent three-dimensional
images of the coronary arteries to assist in the diagnosis and treatment of
CAD. Currently, calcium scoring—measuring the amount of calcium in the
arteries—is used to screen cases of suspected CAD, but is not used in cases
of known CAD. Dr. Hacker and colleagues set out to determine if calcium
scoring would lend additional prognostic value to SPECT findings in patients
with known, stable CAD.
For the study, 260 patients with CAD underwent coronary artery calcium
scoring in addition to SPECT myocardial perfusion imaging. Over a five-year
period, the patients were followed up for severe cardiac events, meaning
cardiac death or non-fatal heart attacks. Twenty-three of the 260 patients
had fatal or severe heart attacks, and 40 others underwent bypass surgery.
The results showed that patients with an initial calcium score greater than
400 were at significantly increased risk for severe heart attack.
"We found that coronary calcium seems to play an important role in
predicting subsequent heart attack or sudden cardiac death, and adds
prognostic value to SPECT findings," co-author Christopher Uebleis, M.D.,
member of the research unit for nuclear cardiology at Ludwig Maximilians
University was quoted as saying.
Dr. Hacker pointed out that combining calcium scoring and SPECT can identify
patients with known CAD who are at greatest risk for serious or fatal heart
attacks. "In these patients,” he said, “intensified medical therapy, shorter
follow-up intervals and, if necessary, bypass procedures may be required to
prevent future severe cardiac events."
SOURCE: Radiology, July 28, 2009
