American College of Cardiology

Risk of Heart Problems Climbs During Winter Months
(ANAHEIM, CALIF.)—Winter is an especially risky time for people with heart disease, according to research presented on March 12 at the American College of Cardiology 49th Annual Scientific Session in Anaheim, Calif. Data from more than 1,200 patients showed that the size of a heart attack was one-third larger during winter and spring than during other seasons, according to a report by Dr. Robert Kloner, who directs research at the Heart Institute at Good Samaritan Hospital in Los Angeles. A separate study, led by Dr. Michael Gold, of the University of Maryland, Baltimore, showed that arrhythmias were far more common during winter. The researchers analyzed data from patients who had an implantable cardioverter-defibrillator—a device that treats patients who develop a seriously abnormal cardiac rhythm by delivering an electrical shock to the heart—and found that the device delivered shocks 40 percent more often during the winter.

A third study showed that flu vaccination may provide some protection against heart attacks during the winter. Dr. Morteza Naghavi and colleagues at the University of Texas Health Sciences Center in Houston found that, among 233 patients with heart disease, the risk of a heart attack was reduced by 67 percent among those who had received a flu vaccine.

The reason for the increased risk in winter is unclear, but the researchers said it may be related to an increase in risk factors, such as body weight and blood pressure; inflammation of the walls of arteries as a result of infection; the response of the cardiovascular system to the cold; or exertion from such activities as snow shoveling.

Laser Treatment Looks Promising to Treat Sickest Heart Patients
(ANAHEIM, CALIF.)—Two studies presented on March 12 at the American College of Cardiology 49th Annual Scientific Session in Anaheim, Calif., suggest that laser treatment can improve the health of the very sickest heart patients, who are otherwise considered inoperable.

In one study, the laser treatment, which creates small channels in blood-deprived heart muscle, significantly improved heart function and exercise capacity in patients with inoperable coronary heart disease, according to result of a large randomized clinical trial that compared percutaneous transmyocardial revascularization (PTMR) and medical treatment. None of the 325 patients in the trial was a candidate for balloon angioplasty or bypass surgery because of the severity of disease. A year later, substantially more PTMR-treated patients had fewer symptoms or no symptoms at all compared to the medical group, said Dr. Emerson Perin of the Texas Heart Institute in Houston. Patients treated with PTMR also had increased ability to exercise on a treadmill, whereas medically managed patients had a decline in exercise capacity.

In another study, using an electromagnetic mapping system to identify areas of reduced blood flow in the heart, cardiologists increased blood flow with the laser treatment, which led to improved heart function and reduced symptoms in patients who had inoperable heart disease. Dr. Ran Kornowski of Washington Hospital Center in Washington, D.C., reported that 70 percent of the 77 patients treated with the map-guided system maintained the improvement during six months of follow-up evaluation, including an increase in treadmill exercise time. The improvement apparently does not relate improved blood flow, however, according to results of imaging studies that assessed blood flow before and after the procedures. The studies showed no difference in flow after treatment, indicating the laser procedure improves heart function by some other means, said Dr. Robert Hendel of Northwestern University Medical Center in Chicago.

Future Looks Bright for Growing Blood Vessels With Genes and Proteins
(ANAHEIM, CALIF.)—Implantation of genetic material from a growth-stimulating gene resulted in significant improvement in chest pain and exercise ability in a group of patients with severe coronary heart disease, according to a study released on March 12 at the American College of Cardiology 49th Annual Scientific Session in Anaheim, Calif. In a related study, investigators found similar, positive results with a protein-based technique.

In the gene study, a total of 30 patients were treated with three different doses of vascular endothelial growth factor-2 DNA. Three months after treatment, 70 percent of the patients had improved by at least two classes on an index of chest pain, and treadmill exercise time had increased significantly, said Dr. Jeffrey Isner of St. Elizabeth's Medical Center in Boston. The therapy also reduced the frequency of chest pain episodes and the use of nitroglycerin to treat chest pain, presumably by stimulating the growth of new blood vessels in the heart.

In another study, treatment with a protein that promotes blood vessel growth reduced the frequency of chest pain in patients with severe coronary heart disease that was not amenable to surgery or balloon angioplasty, according to findings from a multicenter clinical study. Overall, treatment with fibroblast growth factor-2 (FGF-2) did not improve heart function or reduce episodes of angina, or chest pain, said Dr. Michael Simons of Beth Israel Deaconess Medical Center in Boston. However, when researchers analyzed the data according to the severity of coronary disease, they found that the sickest patients derived significant benefit from FGF-2. Specifically, the treatment improved angina in patients who had the worst chest pain before treatment. “This is an encouraging trial because we now have an idea of which patients are likely to benefit most from this treatment, and it sets the stage for the next round of studies,” said Dr. Simons.