MONDAY, Sept. 21 (HealthDay News) -- People suffering from the flu may be at higher risk for having a heart attack, especially those with heart disease and diabetes, British researchers report.

Because both seasonal and the pandemic H1N1 swine flu are circulating this fall and winter, people at risk for heart attacks are urged to get a seasonal flu shot and an H1N1 flu shot, which may reduce the chance of getting the flu and thereby lower the risk for a heart attack, experts say.

"Influenza is most concerning because of its secondary complications," said Dr. Marc Siegel, an associate professor of medicine at New York University School of Medicine in New York City.

"Most of the time with influenza, death or hospitalization isn't because of the influenza, it's because influenza puts you in a weakened state -- it's a stress on the system," he said. "So, it is not surprising that you would have the increased risk of a myocardial infarction during or right after an influenza infection."

In addition, the flu virus may have a negative effect directly on the heart, Siegel said. "Flu stresses and strains the system," he added.

To determine the risk of heart attack among those with flu, a research team led by Andrew C. Hayward, a senior lecturer in infectious disease epidemiology at the UCL Centre for Infectious Disease Epidemiology in London, looked at 39 studies conducted between 1932 and 2008.

The studies showed an increase in deaths from heart disease and more heart attacks during flu season. In fact, excess deaths because of heart disease averaged 35 percent to 50 percent, according to the report in the October issue of The Lancet Infectious Diseases.

But the studies also showed that getting a flu shot reduced the risk of dying from heart disease or suffering a heart attack, Hayward's group found.

"We believe influenza vaccination should be encouraged wherever indicated, especially in those people with existing cardiovascular disease. Further evidence is needed on the effectiveness of influenza vaccines to reduce the risk of cardiac events in people without established vascular disease," Hayward's team concluded.

Dr. Gregg C. Fonarow, a professor of cardiology at the University of California, Los Angeles, agreed that flu shots appear to reduce the risk of heart attacks.

"It has long been hypothesized that influenza infection results in an acute inflammatory response that can also trigger the onset of cardiovascular events such as heart attack and stroke in vulnerable individuals," Fonarow said.

A number of observational studies have suggested more cardiovascular events occur in patients with influenza than otherwise expected and that individuals who receive annual flu shots are much less likely to have fatal or nonfatal cardiovascular events or be hospitalized for heart failure, he said.

"Guidelines from the American Heart Association and American College of Cardiology strongly recommend that all individuals with cardiovascular disease receive annual influenza vaccination," Fonarow said.

However, Dr. Pascal James Imperato, dean and distinguished service professor at the School of Public Health at the State University of New York Downstate Medical Center in Brooklyn, said the role of flu shots in preventing heart attack has not been proven conclusively.

"The role of severe respiratory infections in precipitating myocardial infarctions in vulnerable individuals is well-established," Imperato said. "However, the role of influenza vaccines in protecting such individuals is less clear from the limited scientific evidence available."

More information

For more information on flu, visit the Flu.Gov.

FRIDAY, Sept. 18 (HealthDay News) -- Radiologists have developed a way to gain better insight into signs of heart disease by using cardiac CT scans that detect narrowed arteries and low blood flow.

CT scans use X-rays to create cross-sectional images of the body's internal anatomy. The scans can detect blockages in coronary arteries, but it's hard to tell if they're actually preventing blood from flowing to the heart.

In a new study, published Sept. 15 in the Journal of the American College of Cardiology, researchers at Massachusetts General Hospital explained how to gain more detailed pictures of what is going on inside the body, potentially giving doctors more information about the best treatment.

The research, based on tests in 34 cardiac patients, "is among the first demonstrations of the use of cardiac CT to detect both coronary artery stenosis and resulting myocardial ischemia simultaneously in a single examination," Dr. Ricardo C. Cury, a cardiac imaging specialist at the hospital's Heart Center and the study's principal investigator, explained in a hospital news release.

Though other scanning technologies, including nuclear perfusion imaging, provide information that can help guide patient treatment, such methods can lead to either false-negative or false-positive findings, Cury explained in the news release. The new technique "could improve diagnostic accuracy while potentially reducing costs and radiation exposure," he said.

"Since our study was relatively small, we need to test this approach in a larger multicenter trial," Cury added.

More information

The U.S. Centers for Disease Control and Prevention has more on heart disease.

THURSDAY, June 18 (HealthDay News) -- New research suggests a relationship between low levels of omega-3 fatty acids and an increased risk of depression in heart patients.

The study, reported online in the Journal of Psychotherapy and Psychosomatics, looked at 987 adults with coronary heart disease. Among those with the lowest levels of omega-3 fatty acids, 23 percent suffered from depression. But among those with the highest levels of the fatty acid in their blood, only 13 percent were diagnosed with depressive symptoms.

The findings of this study support the previously reported association between low levels of omega-3 fatty acids and depression in non-hospitalized patients with stable coronary heart disease, according to a news release from the journal. The types of omega-3 measured in the study were docosahexaenoic acid and eicosapentaenoic acid, and the patients' age, sex and race was factored in, the study authors noted.

Omega-3 fatty acids are found in cold water fish, various nuts and other foods, as well as in supplements. Over the years, numerous studies have suggested significant health benefits in consuming omega-3, such as improved cardiac health, reduced cancer risk and improved immune function, according to information from the U.S. National Institutes of Health.

In the new study, led by researchers at the University of California San Francisco, each unit decrease or increase in omega-3 was reflected in a corresponding rise or lowering of depressive symptoms.

Though data strongly suggest an association, the researchers noted that they cannot make a definitive link until they study the connection in a larger and more diverse population. In addition, more research needs to be done to determine how a patient's education and socioeconomic status impacts the link between omega-3 levels and depression, the researchers concluded.

More information

Learn more about omega-3 fatty acids at the U.S. National Library of Medicine.

WEDNESDAY, June 17 (HealthDay News) -- Telephone or Internet-based interventions may help heart attack survivors and other cardiac patients improve their heart health and reduce their risk of future cardiac events, Australian researchers say.

They reviewed published randomized trials evaluating the use of phone- or Internet-based interventions in cardiac rehabilitation programs. Two of the interventions were Internet-based; all others were by telephone.

"We aimed to determine if, in a world increasingly dominated by electronic technology, interventions for preventing recurrent coronary disease could be delivered in innovative ways to enable more people to access effective secondary prevention," the study's lead author, Lis Neubeck of Concord Repatriation General Hospital in Sydney, said in a news release from the European Society of Cardiology.

"Our analysis, which involved more than 3,000 patients across 11 studies, suggests that the electronic age is indeed providing effective alternatives for the delivery of preventive health change," Neubeck added.

The researchers found that patients who took part in these telehealth interventions had a 30 percent lower death rate than patients without the interventions. The telehealth patients also had lower total cholesterol levels, lower levels of systolic blood pressure and lower rates of smoking.

The study appears in the June issue of the European Journal of Cardiovascular Prevention & Rehabilitation.

People are "increasingly time-poor," which can make it difficult for them to attend cardiac-rehabilitation programs at hospitals or other facilities, according to Neubeck, who stated: "Utilizing electronic technologies has the potential to increase access for these services without compromising outcomes."

More information

The U.S. National Heart, Lung, and Blood Institute has more about cardiac rehabilitation.