(November 4, 2008 - Insidermedicine) The first month following a heart attack is the most critical time regarding the risk for sudden cardiac death, and those with heart failure continue to be at higher-than-average risk, according to research published in the Journal of the American Medical Association.

Here is some information about sudden cardiac death:

•    Also known as sudden arrest, it is death resulting from an abrupt loss of heart function that is generally unexpected.

•    While the most common cause of sudden cardiac death is underlying heart disease, it can happen in those with no known heart disease.

•    About 90% who die from sudden cardiac death have two or more of the arteries feeding the heart narrowed by the buildup of fatty material.

Researchers out of the Minneapolis Veterans Affairs Medical Center and Rochester Mayo Clinic examined outcomes among nearly 3,000 individuals who had a heart attack between 1979 and 2005. Patients were followed for an average of five years, through to the end of February 2008.

Overall, the risk for sudden cardiac death following a heart attack dropped by more than 40% for those who had their heart attack between 1997 and 2005, compared with those who had one between 1979 and 1987. Still, in the first month following a heart attack the risk was about four times higher than normal. After the first month, the risk leveled off but remained markedly elevated among those with heart failure.

We had a chance to speak with Dr. Veronique Roger, one of the authors of the study, who offered some further insight

Today’s research clarifies the pattern of risk for sudden cardiac death following heart attack. It demonstrates how this risk is increased in the month following a heart attack and how it remains increased among those with heart failure.