The American Heart Association, Dallas, Texas

Heart Disease Research at The American Heart Association

ByABC News
March 3, 2009, 2:59 PM

— -- Hi. My name is Daniel Jones, and I am the president of the American Heart Association.

Diseases of the heart are the No. 1 killer in America, and stroke is No. 3. The American Heart Association strongly believes that learning more about these diseases is the best way to reduce disability and death. That's why research is an association-wide priority. The American Heart Association is second only to the National Heart, Lung, and Blood Institute (NHLBI) in funding heart research.

To support research, the American Heart Association has invested almost $2.7 billion since 1949 and $145 million in 2005-06 alone. The association currently funds about 2,500 scientists around the United States.

American Heart Association-funded breakthroughs include the first artificial heart valve, techniques and standards for CPR, implantable pacemakers, treatment for infant respiratory distress syndrome, cholesterol inhibitors, microsurgery and drug-coated stents. The association has funded the winners of seven Nobel Prizes.

In recent years, funding from the American Heart Association and NHLBI has enabled University of California-Los Angeles researchers to identify a new molecule that may help regulate the delivery of fats to cells for energy and storage. The finding could lead to a better understanding of how we use fats from the foods we eat.

Digested fats travel to the small intestine, where they are packaged into chylomicrons, which are large, spherical particles filled with triglycerides. The chylomicrons then travel through the bloodstream delivering triglycerides that feed skeletal muscles and the heart — and to adipose tissue that stores the triglycerides for energy. As the chylomicroms pass through the inside walls of capillaries, they are caught by molecules called proteoglycans, which hold chylomicrons steady while the newly-delivered triglycerides are broken down by the enzyme lipoprotein lipase (LpL). The broken-down triglyceride products are then taken up and used by cells.

"Previously, we didn't know what molecule in the capillaries facilitated the capture of chylomicrons and facilitated the interaction with lipoprotein lipase," said Dr. Stephen Young, author of the study and investigator at the David Geffen School of Medicine at UCLA. "We think that we've found the missing piece of the puzzle."

American Heart Association funding from 1985 to 1994 laid the groundwork for these studies.

In Minnesota, a scientist development grant from the American Heart Association's Greater Midwest Affiliate helped fund research that discovered that aerobic arm exercises can delay the onset of leg pain that makes walking even short distances difficult for many people with peripheral arterial disease (PAD).

"This is the first study showing that arm-only aerobics can provide results comparable to those seen with treadmill training," said Diane Treat-Jacobson, Ph.D., R.N., lead author of the study and an assistant professor at the University of Minnesota School of Nursing in Minneapolis.

PAD is a progressive atherosclerotic disease in which plaque builds up and narrows the arteries in the extremities (usually the legs), limiting blood supply to the muscles during exertion. Starved for oxygen, these (usually calf) muscles can cramp and hurt after patients walk even short distances. The leg pain goes away with a few minutes of rest. PAD affects more than 8 million Americans, including about 20 percent of people older than 65 years.

Earlier studies have shown that progressive exercise training on a treadmill can help postpone the onset of leg pain or cramps, known medically as claudication, and can extend the distance patients can walk. In this study, researchers used an arm ergometer, a table-top device akin to bicycle pedals operated with the arms, rather than the legs.

The team measured how far 35 PAD patients (average age 67) could walk on a treadmill without leg pain, and how far they could continue to walk before pain forced them to stop. Then they randomly divided the patients into a control group that didn't exercise and three exercise groups. One group exercised on the treadmill, one on the arm ergometer, and the third group used both. M

The three groups exercised three times a week for 12 weeks in one-hour supervised sessions. After three months of training, patients in all three exercise groups improved in the total distance they could walk, ranging from 150 to 330 meters (equivalent to two to three and a half blocks). Both treadmill and arm exercisers showed similar improvement in the distance they could walk without pain: more than 100 meters, or about one and a half blocks.

"We were happy to discover that upper-body aerobics can help patients with PAD increase the distance they can walk without pain," Treat-Jacobson said. "We need additional studies to confirm the results, better understand why and how this works, and also identify the best training regimen for patients. In the meantime, our results provide evidence that aerobic upper-body exercise is a pain-free alternative for patients with PAD who cannot or do not wish to perform treadmill exercises because of leg pain or some other disability."

Click here for more information on research funded by the American Heart Association.