Heart attacks occur when blood flow through the arteries to the
heart (coronary arteries) is blocked for a long enough time to
damage or kill a portion of heart muscle. Within days to months
after the heart attack, doctors sometimes inject dye through a
catheter into the coronary arteries (heart catheterization) to
see where they are narrowed or blocked. Doctors do the
catheterization to find out whether patients need major
procedures (coronary artery bypass graft surgery or angioplasty)
to help prevent future heart attacks and chest pain (angina).
Some patients with heart attacks do not need catheterizations.
They may have very low risks for future problems, or they may
have other illnesses, such as liver failure, which preclude
heart surgery. Some, but not all, research suggests that women
in the United States have catheterizations after heart attacks
less often than men. Even if women have these procedures less
often than men, we do not know whether the procedures are
inappropriately underused in women com