MRA 3-D Imaging To Diagnose Heart Disease  

	June 22, 1999 - A new technique called magnetic
resonance angiography (MRA) allows doctors to take 3-D
images of the heart. These pictures help diagnose coronary
heart disease without doing a heart cath. MRA uses magnetic
pulses to provide clear 3-D pictures of the blood vessels
that supply blood to the heart.
	Researchers performed MRA in 8 healthy adults and
5 patients with confirmed coronary heart disease. Among
patients with heart disease, the images did correspond
with the patient's degree of disease.
	The new procedure takes 10-30 minutes and does not
require x-rays or injections, according to results published
in the June 22nd issue of Circulation: Journal of the
American Heart Association. Conventional angiography requires
a heart cath, during which a small tube is inserted into the
body via a major vessel in the groin and is guided into the
heart. A series of x-rays is taken while dye is injected
into the coronary arteries to see if blockages are present.
	Cardiac cath takes less than an hour for most
patients, but they must recover for 4 or more hours before
being discharged from the hospital. Heart cath also carries
a risk of infection and bleeding, and in a very small number
of cases, heart attack and stroke.
	MRA takes about 30 minutes and may cost a lot less.
The study's author says, "We have multiple methods to test
patients for coronary heart disease. However, we have no
methods to image the coronary arteries themselves that do not
require injecting dye." With the new MRA technique, 2 sets
of images are taken: one for the blood vessels on the left
side of the heart and one for the right side, with each set
of images taking 10 to 15 minutes.
	Researchers first reported that MRA could be used
for coronary artery imaging in 1993 but patients had to hold
their breath 30 to 40 times for about 16 to 20 seconds each
time and images were not clear enough to be useful. A study
has begun to test the accuracy of this technique compared to
x-ray angiography at 8 medical centers.