CHICAGO -- A study suggests that angioplasties can be safely done at hospitals regardless of whether they have cardiac surgery departments, a finding that could extend the lifesaving procedure to thousands of U.S. heart attack patients.

The study, which appeared in Wednesday's Journal of the American Medical Association, challenges the conventional notion that angioplasties should only be performed at hospitals with a special cardiac unit.

The study involved giving three months of angioplasty training to staffers at 11 of such hospitals. Angioplasty, in which a tiny balloon is used to open a clogged artery, is considered the best treatment for heart attacks.

Following the training, researchers found that angioplasty patients fared about as well in regular hospitals as those who undergo the procedure at surgery-ready hospitals.

About two-thirds of U.S. heart attack patients each year do not get angioplasties because they are taken to hospitals without cardiac surgery units. In fact, most U.S. hospitals do not have such units. Both St. Francis Medical Center and Southeast Missouri Hospital in Cape Girardeau offer cardiac surgery and angioplasty procedures to patients.

The study offers hope to heart attack victims without access to such special departments.

Angioplasty is not considered surgery. It typically involves threading a thin tube, or catheter, tipped with a deflated balloon into an artery, where the balloon is inflated to clear a blockage. Small tubes called stents often are installed during the procedure to keep the artery propped open; 70 percent of angioplasty patients studied received them.

At six weeks and six months after their heart attacks, patients treated with angioplasty had 40 percent lower rates of death, strokes and recurrent heart attacks than those given the clot-dissolving medication Activase. They also had shorter hospital stays, and none had complications requiring surgery.