Mini heart attacks may stop big damage

Briefly cutting off the flow of blood to arteries around the heart can offer protection from major heart attacks, a new study says. Researchers said the technique could show a way toward drugs that protect those at high risk for heart attacks and strikes. For now, it could help prevent damage during bypass surgeries. Fatty deposits build up in the walls of blood vessels. When they burst, it can cause blockages that cut off blood supply, known as ischemia. That causes cells in the heart to die. But when blood flow comes back, the reperfusion throws off cell chemistry, which can destroy cells. So, even when the blood supply returns, there is still a risk of heart failure. The technique of quickly cutting off then restoring the flow seems to prepare the cells, according to a news release. The process is called ischemic preconditioning. The new research found a molecule that seems to be involved in providing the protection. It occurs naturally, but doctors want to harness it to protect people at risk. "Obviously, this natural response, when it follows a major heart attack, is often too little too late. Our hope is that boosting the effect in patients at high risk, perhaps by administering (the molecule) beforehand, will reduce heart attack damage in the future. Even sooner, we may be able dramatically reduce reperfusion injury suffered in surgical settings," said Dr. Paul S. Brooks of the University of Rochester Medical Center. The work appears in the journal Cardiovascular Research.