Chemicals released in response to overwhelming emotional stress can be temporarily toxic to the heart, effectively stunning the muscle and producing symptoms similar to a typical heart attack, including chest pain, fluid in the lungs, shortness of breath and heart failure.

Researchers at Johns Hopkins have discovered that sudden emotional stress can result in severe, but reversible, heart-muscle weakness that looks and feels like a classic heart attack. Patients with broken heart syndrome often are misdiagnosed with a massive heart attack when, indeed, they have suffered from a days-long surge in adrenalin (epinephrine) and other stress hormones that temporarily "stun" the heart.

Toxic Chemicals Released

"Our study should help physicians distinguish between stress cardiomyopathy and heart attacks," says study lead author and cardiologist Ilan Wittstein, M.D., an assistant professor at The Johns Hopkins University School of Medicine and its Heart Institute. "And it should also reassure patients that they have not had permanent heart damage."

In the Hopkins study, to be published in The New England Journal of Medicine online February 10, the research team found that some people may respond to sudden, overwhelming emotional stress by releasing large amounts of catecholamines (notably adrenalin and noradrenalin, also called epinephrine and norepinephrine) into the blood stream, along with their breakdown products and small proteins produced by an excited nervous system.

These chemicals can be temporarily toxic to the heart, effectively stunning the muscle and producing symptoms similar to a typical heart attack, including chest pain, fluid in the lungs, shortness of breath and heart failure.

Fast, Complete Recovery Common

Upon closer examination, though, the researchers determined that cases of stress cardiomyopathy were very different clinically from a typical heart attack.

"After observing several cases of 'broken heart' syndrome at Hopkins hospitals -- most of them in middle-aged or elderly women -- we realized that these patients had clinical features quite different from typical cases of heart attack, and that something very different was happening," says Wittstein. "These cases were, initially, difficult to explain, because most of the patients were previously healthy and had few risk factors for heart disease."

For example, examination by angiogram showed no blockages in the arteries supplying the heart. Blood tests also failed to reveal some typical signs of a heart attack, such as highly elevated levels of cardiac enzymes that are released into the blood stream from damaged heart muscle.

Magnetic resonance imaging (MRI) scans confirmed that none of the stressed patients had suffered irreversible muscle damage. Of greatest surprise, the team says, was that recovery rates were much faster than typically seen after a heart attack. Stressed patients showed dramatic improvement in their hearts