Some cot deaths linked with heart condition

A study suggests 5 per cent of sudden infant death syndrome cases may be caused by an electrical problem in which the heart recharges itself too slowly.

About 3000 infants die each year in the United States of SIDS, the sudden and unexplained death of an infant under the age of one year.

Previous research has also suggested sleeping on the stomach, nervous system problems related to breathing, abnormal metabolism in the liver and flaws in the heart's electrical channels could be among the causes.

The American Academy of Paediatrics recommends infants be placed on their backs to sleep, and studies have indicated that change has reduced the incidence of SIDS.

The study, released last week at the American Heart Association meeting in Chicago, found that in one out of 20 cases of SIDS, the baby has a problem similar to a heart condition called long Q-T syndrome that sometimes causes sudden death in young people and adults.

With long Q-T syndrome, the heart electrically recharges itself too slowly or in a disorganised way, ahead of the next heartbeat, and that can sometimes cause the heart to stop pumping.

An estimated one in 5000 people may suffer from the syndrome.

The researchers, led by Michael Ackerman, from the Mayo Clinic, performed a genetic autopsy on every unexplained infant death investigated in Arkansas from September 1997 to August 1999.

There were 93 cases.

"Long Q-T syndrome is sometimes called the perfect killer, because it leaves no clues," Dr Ackerman said.

"Neither does SIDS."

Dr Ackerman urged medical examiners to store tissue in cases of sudden infant deaths in a way that would allow researchers to carry out a molecular autopsy in order to continue to study the possible causes of SIDS.

- REUTERS

Herald feature: Health