The American Heart Association's "Top 10 Research Advances for 2005" list (see related story) is just the tip of the iceberg when it comes to what's new in the field. Below is another small sampling of recent discoveries and studies that will hopefully add to our medical arsenal in the fight against heart disease and stroke. - At the American Heart Association's annual scientific sessions in Dallas in mid-November, Johns Hopkins scientists presented their latest findings on creating a biologic pacemaker. In guinea pig experiments, the scientists fused common connective tissue cells taken from lungs with heart muscle cells to create a safe and effective biological pacemaker whose cells can fire on their own and naturally regulate the muscle's rhythmic beat. "This work with fibroblasts could pave the way to an alternative to implanted electronic pacemakers," says Dr. Eduardo Marbán, professor and chief of cardiology at Hopkins and its Heart Institute. "Such a 'biopacemaker' is a potentially important option for patients at too high a risk for infection or who are physically too small to accommodate mechanical pacemakers." The Hopkins findings are among several approaches scientists are taking to develop biopacemakers. What makes this approach different, says Hee Cheol Cho, PhD, a postdoctoral cardiology research fellow at Hopkins, is that the fibroblasts are found throughout the body, even in skin. "They proliferate well and grow fast and when fused with heart muscle, form cells that are very stable." Of other approaches, he adds, "It is very difficult to guide stem cells into forming exactly the kind of cell needed, but not so with fibroblasts." - Johns Hopkins researchers also presented their findings on stem cell research at the American Heart Association's annual scientific sessions. Stem cells derived from human heart tissue develop into multicellular, spherical structures called cardiospheres that express the normal properties of primitive heart tissue, smooth muscle and blood vessel cells, according to the research. In a related study, cells grown in the laboratory from these cardiospheres and injected into the hearts of mice following a lab-induced heart attack migrated straight to damaged tissue and regenerated, improving the organ's ability to pump blood throughout the animal's body. "The findings could potentially offer patients use of their own stem cells to repair heart tissue soon after a heart attack, or to regenerate weakened muscle resulting from heart failure, perhaps averting the need for heart transplants," says Marbán, senior author of both studies. "By using a patient's own adult stem cells rather than a donor's, there would be no risk of triggering an immune response that could cause rejection." -The same philosophy used to make better cars and computer chips can also save the lives of heart attack patients, according to a study published in the October issue of the Journal of the American College of Cardiology. The study was led by University of Michigan Cardiovascular Center co-director Dr. Kim Eagle, FACC, and sponsored by the American College of Cardiology as part of the Guidelines Applied in Practice (GAP) initiative. The study involved 2,857 patients, of whom 1,489 were treated after the initiative started. After implementing quality improvement measures, 26 percent fewer patients died in the first year after their heart attack. The steps included a checklist that doctors, nurses and patients in 33 Michigan hospitals had to complete before each patient could leave the hospital. The checklist, based on national heart-care guidelines, helped make sure that patients got crucial drugs, tests and lifestyle advice that could help prevent another heart attack. "Medicine based on memory alone is unreliable," Eagle says. "Guidelines for care, when embedded into a system used by doctors, nurses and patients alike, can improve care and translate into improved outcomes for patients." The new results are the first to show that increased use of proven therapy and patient-involvement techniques can actually reduce the risk of death soon after patients leave the hospital. - New research suggests patients who develop antibodies to the anti-clotting drug heparin nearly double their risk of death or serious complication after heart surgery. "Complications after heart surgery are typically attributed to the surgery alone," says Dr. Thomas Slaughter, co-principal investigator on the project and a professor of anesthesiology at Wake Forest University Baptist Medical Center. "Our study examined whether development of heparin antibodies before surgery poses an independent risk." The study, which involved 466 patients scheduled to undergo either coronary artery bypass or valve replacement surgery, was reported in the December issue of Journal of Thoracic and Cardiovascular Surgery. Conducted by investigators at Wake Forest University Baptist and Duke University medical centers, it is the first study to convincingly demonstrate a relationship between heparin antibodies and complications after cardiac surgery. Heparin is administered intravenously during many procedures, including kidney dialysis, heart catheterization or angioplasty, as well as during heart and vascular surgeries. Estimates suggest that nearly half of patients treated with heparin develop the antibodies, which may last for months. The researchers theorize that in patients with heparin antibodies, subsequent treatment with heparin activates blood components that cause clotting and inflammation, increasing the risk for heart attacks, heart rhythm problems, strokes and other complications. "While it is too early to recommend universal testing for the antibodies, our study is the most definitive evidence to date that heparin antibodies increase the risk for death and complications associated with cardiac surgery," said Slaughter. - A Mayo Clinic research team discovered that heart attack patients have a 44-fold increased risk of stroke in the 30 days following the heart attack compared with the general population. "While our research reaffirmed the risk of stroke among patients with heart disease, the surprise was that the risk was so high in the month after a heart attack," says Dr. Veronique Roger, the Mayo Clinic cardiologist who led the study. Researchers reviewed the medical records of 2,160 patients who received care for a heart attack at Mayo Clinic between 1979 and 1998 to see whether the patients had a stroke and/or died after the heart attack. Patients were followed for about six years. In addition to the high risk in the first 30 days, the stroke risk remained two to three times higher than expected during the first three years following the heart attack. Older age, previous stroke and diabetes increased the risk for stroke. The results can serve as a wake-up call to healthcare providers to know about this increased risk. Further studies will help define what can more specifically be done to prevent strokes after heart attacks, Roger says.