March 26 (HealthDay News) -- New details about the symptoms and outcomes of a relatively rare but potentially life-threatening condition called broken heart syndrome have been collected by U.S. researchers into a registry of people treated for the syndrome.

Two-thirds of the 70 people in the new registry -- nearly all postmenopausal women -- had suffered an extremely stressful emotional or physical event just before they arrived at a hospital with heart attack-like symptoms. About 20 percent of them were critically ill and required emergency room treatment to keep them alive, but all had a full recovery, the researchers said.

"It can be difficult for cardiologists and emergency room physicians to diagnose and manage patients with broken heart syndrome," Dr. Richard Regnante, an interventional cardiology fellow at The Miriam Hospital in Providence, R.I., and lead author of the study, said in a news release from the hospital. "However, this data will help us better understand the disease process and could play a major role in developing and tailoring more effective short- and long-term treatment strategies."

A report on the registry and its findings is in the April 1 issue of the American Journal of Cardiology.

Unlike heart attacks, broken heart syndrome -- officially known as Takotsubo cardiomyopathy -- occurs most often in spring and summer months. Symptoms typically mimic a heart attack and usually occur after someone has been through an intense emotional or physical event -- a domestic argument, bad news about a family member, severe physical illness or a car accident.

It's believed that the symptoms of broken heart syndrome are caused by the heart's reaction to a surge of adrenaline and other stress hormones that cause part of the heart to temporarily weaken or become stunned.

But, with quick treatment, it seems that broken heart syndrome is temporary and completely reversible, the researchers said.

"Although there is much we're still learning about broken heart syndrome, we do know that it is rarely fatal as long as patients are fully supported with medications, respirators and other critical devices in the first 48 hours," Regnante said.

SOURCE: The Miriam Hospital, news release, March 26, 2009