Washington: It has been proved that chances of a heart attack shoot up 21-fold within the first 24 hours after the loss of a loved one.

The risk of heart attack remained eight times above normal even during the first week after the death of a loved one, slowly subsiding, but still remaining elevated for at least a month, according to a new research.

"Some people would say a 'broken heart' related to the grief response is what leads to these physiologic changes," says study author Murray Mittleman, cardiologist at the Beth Israel Deaconess Medical Centre.

"So that emotional sense of the broken heart may actually lead to damage, leading to a heart attack and a physical broken heart of a sort," adds Mittleman, also associate professor of medicine at Harvard Medical School.

Researchers interviewed 2,000 patients who suffered myocardial infarctions, or heart attacks, over a five-year period.

While there is widespread anecdotal evidence, a few studies have looked at the acute effect of bereavement and grief on myocardial infarction (heart attacks). Patients were queried about potentially triggering events, including losing someone close to them in the past year.

"Bereavement and grief are associated with increased feelings of depression, anxiety and anger, and those have been shown to be associated with increases in heart rate and blood pressure. And changes in the blood that make it more likely to clot, all of which can lead to a heart attack," says Elizabeth Mostofsky, post-doctoral fellow in cardiology at Beth Israel.

Mostofsky and Mittleman think that being aware of the heightened risk can go a long way toward "breaking the link between the loss of someone close and the heart attack."