Exploiting the body's ability to fight a heart attack

"Scientists trying to find a way to better help patients protect themselves against harm from a heart attack are taking their cues from cardiac patients. The work has its roots in a perplexing curiosity that physicians have long observed in their patients: When faced with a heart attack, people who have had a previous one oftentimes fare better than patients who have never had one. Scientists have been working for 25 years to understand one reason why – a process known as ischemic preconditioning, where a temporary restriction of blood flow somehow strengthens cardiac tissues down the road. In the latest research, published online February 25 in the journal Circulation Research, a group led by Paul Brookes, Ph.D., and graduate student Andrew Wojtovich at the University of Rochester Medical Center have developed new methods in the effort to track down one of the key molecular agents involved. That molecule, known as the mitochondrial ATP-sensitive potassium channel, or mKATP, is central to ischemic preconditioning, but it has proven elusive for scientists seeking to isolate and describe it"

Simple, cheap procedure can limit size of heart attack: Researchers (Canada)

"Simply blowing up a blood pressure cuff around a person's arm when they're having a heart attack can reduce the amount of permanent heart muscle damage by up to half, an international team of researchers co-ordinated from the Hospital for Sick Children in Toronto has found. Although it goes by the rather unwieldy name "remote ischemic preconditioning" the technique, developed by a doctor at SickKids, is exquisitely simple, cheap and apparently safe. It involves inflating a standard blood-pressure cuff on the upper arm of someone having a heart attack for five minutes, and deflating it for another five minutes, repeating the cycle four times. The procedure exploits the most powerful, inborn protective mechanism the human body uses to protect its tissues from harm. Cutting off blood flow in the arm in short, brief bursts, then restoring it again, causes the body to release a substance in the blood that sends a message around the entire body that something bad is about to happen. It warns and protects the heart from subsequent damage by triggering changes in heart cells so that they can better resist the lack of blood flow. It also makes white blood cells react less aggressively, causing less damage after the heart attack. In a study published in this week's issue of the prestigious medical journal the Lancet, an international team co-ordinated by SickKids showed that, when done by a paramedic en route to hospital and a catheterization lab, ischemic preconditioning can reduce the size of heart attacks by 30 to 50 per cent"