The Future of Heart Health
Stem cell transplantation, accessible defibrillators among innovative research
MONDAY, Nov. 24, 2003 (HealthDayNews) -- The blizzard of new findings presented at the American Heart Association's recent annual meeting show just how far science is progressing: There are now defibrillators that are easier to use than a VCR and techniques that may enable a damaged heart to repair itself.
"It's always exciting. We're always moving forward," says Dr. Edwin C. Weiss, a clinical assistant professor of medicine at New York University School of Medicine in New York City, who attended the meeting. "We've got to move forward. If we just stay stable, we're moving backwards."
Highlights of the meeting also signal the direction of future research:
- One of the most exciting areas is that of stem cell transplantation, says Dr. Augustus Grant, president of the American Heart Association. Hearts that are damaged -- by a heart attack, for instance -- lose some of their ability to contract and pump blood. The traditional treatment has been to use drugs to try to counteract the damage, but that method doesn't actually rejuvenate the heart.
Now, however, researchers can inject stem cells derived from a person's own bone marrow into a damaged heart to see if the cells will generate the heart.
"These strategies are designed to alter the repair process so that lost muscle cells are replaced by cells that have the potential to lead to a new generation of new muscle cells and preserve function," says Grant, co-director of the Heart Station and professor of medicine at Duke University Medical Center in Durham, N.C.
- Something similar is happening in the area of heart valves.
Researchers are taking stem cells from a person's vein and placing them on the scaffold of a valve donated by someone else. The donated valve has been stripped of its lining and consists only of the collagen that holds it together. The stem cells grow on the valve so that it soon is covered by the person's own cells. That valve does not actually go in the heart, but rather replaces a pulmonary valve, which services the lung. The pulmonary valve, in turn, goes into the aortic valve.
"You want a more durable valve in the aortic position," Weiss explains. After a while, the collagen base also is replaced by the recipient's own collagen. The procedure has been done in a small number of people, with promising results.
- Public access defibrillators, which now are available in places such as airports, restaurants and bus and train stations, apparently are saving a great many lives. "People should be learning to use them, should be asking questions to their doctors and public officials and having them put in," Weiss says. "They're making quite a difference."
- Researchers have confirmed the efficacy of a new type of stent, which is used to prop open arteries. The stent is coated with medication that helps reduce the inflammation and scarring that can cause arteries with regular stents to close up again. There have been reports of deaths from the stents, which were approved in April, but apparently not at rates higher than those seen in the clinical trials.
"This is very good news because it is supporting what the early research data did show: a significant reduction in restenosis of the stent area," Weiss says.
- Dual-chamber devices are "clearly showing an improvement in survival in patients and an improvement in quality of life," Weiss says. "They have really shown that they are incredibly useful adjuncts to the current therapy that we use to treat heart failure."
Despite such optimistic reports, the meeting also presented troubling news -- namely, figures on a rising tide of obesity, diabetes and metabolic syndrome, especially in children.
"The number of people that need stents and pacemakers are a small proportion of the people who have gathering obesity [and] who are putting themselves at risk of diabetes, stroke and kidney failure," Weiss says.
One in eight children has metabolic syndrome, a precursor to diabetes, heart disease and other troubles, researchers report. More and more adults and children alike are obese.
"Doctors really need to be on target," Weiss says. "We need to emphasize healthy lifestyle. It may not be new, but it's the most important thing that came out of the meeting."