New drugs help heart attack victims

Dr. Lopaschuk

Thirty-five year old Barry Boroditsky was on his way to work one Monday morning when he felt pain in his chest, and shortness of breath. This was the second time he felt the pain and decided to go the hospital, just to be sure. As it turns out, he had a heart attack. Boroditsky is now thinking about what changes he will have to make in his life and what, if any, permanent damage he has suffered. He is naturally concerned about his future.

Dr. Gary Lopaschuk, professor and director of the Cardiovascular Research Group, may have the answer for Boroditsky and others. Lopaschuk and his colleagues have been working on a unique approach to helping those who have suffered heart attacks.

"This is a completely novel approach to treating heart attacks. Existing treatments either try to increase oxygen supply to the muscle, or to decrease the oxygen use. What this approach does is actually make the muscle more efficient. You get more work for less oxygen and therefore there is less energy demand and less likelihood the muscle will get injured following a heart attack," says Lopaschuk. "We're making the heart do more work with less oxygen."

The body normally uses a good balance of fat and sugars, or carbohydrates, as fuel for the heart muscles. Lopaschuk says during and following a heart attack, the heart uses too much fat and very little sugar. This makes the heart inefficient and can contribute to muscle damage after a heart attack. Lopaschuk says his new drug will help to correct this.

"These drugs will shift the fuel use of the heart towards sugar and away from fatty acids and put that balance of sugar and fat use back into place," he says. "One of the problems with a heart attack is often the muscle is injured and so the patient can have a symptom called congestive heart failure - where they don't have proper muscle function. What we hope this drug will do is lessen the likelihood of them developing heart failure by actually saving the muscle following a heart attack," says Lopaschuk. "The end result is that there will be less damage to the heart."

Lopaschuk has received support from AHFMR's Technology Commercialization Program, the MRC, the Heart and Stroke Foundation of Alberta and the Northwest Territories and the Canadian Diabetic Association. Lopaschuk started his own company called Metabolic Modulators Research Ltd. to help him commercialize the drugs and any spin-offs.

The new drugs are in clinical trials and while their use may be a few years away, Lopaschuk is excited about the range of use for the drugs. "We perceive this happening in a number of occasions. One is for patients who come into the emergency room after a heart attack. It can be used orally in the setting of angina where people get chest pain due to lack of oxygen to the heart and it can lessen the likelihood of getting an angina attack or lessen the severity of the angina attack, " says Lopaschuk. The drug also has applications in patients after cardiac surgery and in infants requiring heart operations.

Lopaschuk has been working with Heritage researcher and pediatric cardiovascular surgeon, Dr. Ivan Reybeka, and pediatric cardiologist, Dr. Ruth Collins-Nakai, to test some of the new compounds on desperately sick newborns. "The same problems that occur with an adult with a heart attack occur in an infant who has to undergo heart surgery-they use too much fat. The benefit is actually greater with this approach in infants," says Lopaschuk.

Lopaschuk says between 300 to 400 children have operations in Alberta every year for congenital heart defects, with Edmonton the surgical centre for much of Western Canada.

The results in infants have been promising. And helping them makes Dr. Lopaschuk's heart feel good.