Researchers Evaluate Safer, More Convenient Heart Disease Test
May 22, 2000 -- Last Friday, Jose Armstrong had a magnetic resonance imaging
test (MRI) for heart disease. He lay in a narrow chamber for about an hour,
bombarded by FM radio waves, while his doctors observed the blood flow through
his heart, giving him occasional instructions though earphones.
Later the same day, Armstrong had an angiogram -- another, much more common
way to evaluate the heart. His doctors injected a local anesthetic into his
groin, inserted very thin tubing into an artery, and pushed it upward until it
entered blood vessels in his heart. A dye was injected into the tube, and
X-rays allowed his doctors to see whether the arteries in his heart were
Both of these tests are somewhat unusual experiences, Armstrong says.
"The MRI can be intimidating, because you lie in a narrow, enclosed space.
But fortunately I'm not claustrophobic. During the angiogram, you feel a rush
of heat when they release the dye into your artery." Most importantly,
Armstrong adds, "the angiogram is an intrusion into your body, while the
MRI gives your doctors a picture of your heart without any intrusion."
Armstrong, 65, lives in Ponce, Puerto Rico. He was visiting his daughter in New
York City when he developed chest pain and went to Mt. Sinai Medical Center for
"The angiogram is the currently accepted diagnostic tool for coronary
artery blockages," says Zahi Fayad, PhD, who has been studying MRIs and
heart disease for 10 years. "We also did an MRI on Mr. Armstrong as part of
our ongoing research, so we can compare the results of the two tests."
Fayad is assistant professor of medicine at Mt. Sinai School of Medicine in New
York City and director of cardiovascular imaging at Mount Sinai Medical
A just-released study says MRI can be an effective way to evaluate patients
after they have had an angioplasty -- which is a procedure to open blocked
heart arteries. About 500,000 people have angioplasties each year. During this
procedure, a tiny balloon is inserted into closed heart arteries and inflated
to open them back up. Unfortunately, in about a third of cases, the arteries
close back up within six months. Currently, the angiogram is the accepted test
to see whether this has happened. However, because it involves threading a fine
tube into the heart, it carries some risks.
"We've developed a rapid, noninvasive, low-risk way to find out, if
you've had an angioplasty, whether your arteries have blocked up again,"
says W. Gregory Hundley, MD, lead author of the study. "You don't have to
have an angiogram, and the result is equivalent." Hundley is assistant
professor of internal medicine (cardiology) and radiology at Wake Forest
University Baptist Medical Center in Winston-Salem, N.C.