Doctors must learn to spot hearts broken by stress rather than by classic heart disease.© Punchstock

Being 'broken-hearted' as a result of emotional trauma may be a more apposite turn of phrase than we imagined. US researchers have shown how sudden emotional stress can release hormones that stun the heart into submission, resulting in symptoms that mimic a typical heart attack.

People suffering from stress cardiomyopathy, or 'broken-heart syndrome', seem to be having a heart attack: they have chest pain, fluid in the lungs, shortness of breath and heart failure. But although the ability of the heart to pump is significantly reduced and the heart muscle is weakened, it is not killed, or infarcted, as in a classic attack.

"The tissue is alive," says Hunter Champion of Johns Hopkins Hospital in Baltimore, Maryland, who led the study. "It's just not moving."

In 1999, Champion and a fellow Johns Hopkins cardiologist, Ilan Wittstein, noticed something unusual about certain heart-attack patients. They were particularly struck by results from postmenopausal women who had experienced an intense emotional event before their attack, such as the loss of a loved one or a court appearance. These patients had unique electrocardiogram and ultrasound patterns, lacked coronary artery disease and recovered quickly.

Between November 1999 and September 2003, Champion and Wittstein gathered biochemical and imaging data for 19 patients suffering from stress cardiomyopathy and compared them with 7 classic heart-attack patients.

The researchers found that initial levels of hormones called catecholamines (particularly adrenaline) in the patients with broken heart syndrome were 2 to 3 times greater than those in classic heart-attack patients, and between 7 and 34 times greater than in healthy people.

"This is the first time the strong association of elevated catecholamine levels and this syndrome has been shown," says Champion.

Japan ahead

Stress cardiomyopathy has been known for ten years in Japan, where it is called takotsubo cardiomyopathy, after an octopus trap with a round bottom that resembles the appearance of a stunned heart.

The disease has so far gone relatively unrecognized in the West, but studies such as Champion's are bringing it to the fore, says Barry Maron, a cardiologist at the Minneapolis Heart Institute Foundation, Minnesota. Maron describes the disease in this month's Circulation¹ and Champion's study is being published online by the New England Journal of Medicine².

It will be important that doctors appreciate the difference between broken-heart syndrome and classic heart disease when examining patients, says Maron. "It is a separate disease entity that has to be distinguished in differential diagnosis."

By spotting broken-heart sufferers, "unnecessary procedures could be averted", says Champion, referring to defibrillator implants. What's more, as doctors learn to recognize the syndrome's unique features, more cases are likely to be documented. "This may be the tip of the iceberg," says Champion. "It may occur much more frequently than we think."

The next step for the Johns Hopkins team is to work out the mechanism by which stress hormones stun the heart. They also aim to set up a stress cardiomyopathy registry to gather information from broken-hearted patients. This, Champion hopes, could reveal whether there is a genetic predisposition for the disease, and why older women seem to be more vulnerable. 

cardiologist at Johns Hopkins School of Medicine

cardiologist at Johns Hopkins School of Medicine

• References

  1. Sharkey S., et al. Circulation 111, 472 - 479 (2005). | Article | PubMed |
  2. Wittstein I., et al. N Engl J Med 352, (2005). | Article | PubMed |