July 31, 2003 -- — Having your heart stop is a chilling experience, but for no one more so than Doug Bowerman.
Two years ago, Bowerman suffered from cardiac arrest. And while doctors were able to start his heart again, precious minutes had already ticked away without oxygen going to his brain.
Luckily, Bowerman was a candidate for an experimental cardiac arrest therapy where the body temperature is lowered almost 10 degrees. The procedure may have saved him from severe and incapacitating brain damage.
"I think I was very lucky that I was a candidate for that research, … and that I didn't have any neurological damage," Bowerman told ABC's Good Morning America.
Dr. James Grotta, the neurologist at the University of Texas-Houston Medical School who treated Bowerman, described the procedure's effectiveness: "The mortality rate [for cardiac arrest] is cut in half … and the percentage of patients who completely recover is doubled."
Hypothermia: More Than a Cold Shoulder
Across the nation, doctors are steadily perfecting the method of healing cardiac arrest patients using hypothermia.
The cooling therapy, which lowers a patient's body temperature up to 9 degrees Fahrenheit, has shown remarkable promise in protecting against brain damage after a heart stoppage.
Cardiac arrest victims are generally resuscitated as soon as possible with automatic ventricular defibrillators — the same paddles that have been popularized by Hollywood lore.
But problems arise when "the short pause in delivering oxygenated blood to the brain [results in] severe irreversible damage," explains Dr. Richard Stein, spokesperson for the American Heart Association, "such that the patient never regains consciousness."
Stein added that recent studies have suggested that depriving and then suddenly replenishing the brain's oxygen can lead to serious side effects.
But keeping revived patients under wraps — of cold blankets and ice packs, that is — may help prevent brain damage and promote recovery.
Studies have consistently demonstrated the effectiveness of hypothermic treatment in the absence of a heartbeat, so much so that the American Heart Association recently urged physicians around the world to start implementing the approach.
The Heart — A New Muscle to Ice
Researchers are trying to expand use of this cold concept to treat the heart itself, by minimizing damage in any part of the organ that has lost its blood supply due to a heart attack.
Dr. William O'Neill, director of the cardiovascular disease division at Beaumont Hospital in Royal Oak, Mich., is confident that lowering the temperature of blood flowing into the heart will significantly improve heart function and recovery.
According to O'Neill, hypothermia decreases the metabolic energy requirement of heart muscle and blunts the inflammatory response that is generally considered to be harmful to heart muscle.
"Physiologists have known for forty years that hypothermia is the most dramatic myocardial protective agent that exists," added O'Neill. "It is used often in open heart surgeries, but there has never been a way in conscious patients."
O'Neill's team appears to have found a way, and they are confident the procedure could reduce the size of heart attacks by as much as 65 percent.
Don't Try This at Home
With all this promise, relatives and friends of victims might wonder if they can do more to help. But doctors warn against taking this treatment into your own hands as you wait for the ambulance.
Dr. Joseph Ornato, chairman of emergency medicine at the Virginia Commonwealth University Health System in Richmond, notes most people can do little to change the body temperature of victims in the midst of cardiac arrest: "Placing any cooling material over a victim awaiting EMS arrival would be of no value since, with no circulation, it would not alter the core temperature."
Moreover, O'Neill warns that cooling heart attack victims without proper training and equipment can lead to intense shivering, with potentially harmful side effects.
Dr. Peter Shulman, cardiologist and professor at the University of Connecticut School of Medicine in Fairfield, echoes O'Neill's sentiments. "In the early phases of a heart attack, there are no data to suggest that cooling is beneficial. It's conceivable that it could be harmful."
So, it might be a while before you start seeing ice buckets in your local emergency room, since much remains to be learned before hypothermic therapy becomes widespread clinical practice.
Concludes O'Neill: "A year from now we'll have a much better understanding of who, when, and how to use cooling for heart attacks. Not every patient will benefit."