Using electrodes to test the electrical activity of the heart is unlikely to help doctors figure out who is at risk of coronary heart disease, according to new recommendations from a government-backed panel.

The United States Preventive Services Task Force wrote on Monday that there's no good evidence the test, called an electrocardiogram, or ECG, helps doctors predict heart risks any better than traditional considerations such as smoking, blood pressure and cholesterol in people with no symptoms.

"It could potentially be helpful if we had evidence that doing a test like an ECG or an exercise ECG would better classify the people who are at high risk" of heart disease, said Dr. Joy Melnikow, a member of the task force from the University of California, Davis.

"Then we could intervene more actively with the very high-risk group which has the highest potential to benefit," she told Reuters Health.

But as of now, Melnikow added, no studies have shown that's the case.

The task force recommends against ECG screening of people considered at low risk for heart disease and says there's not enough information to rule one way or the other on those at intermediate or high risk.

On the other hand, there are both costs and possible harms associated with screening healthy adults, Melnikow pointed out.

Her group's statement was published Monday in the Annals of Internal Medicine.

"The concern is that if people are already at low risk of heart disease and they have one of these tests, if they have an abnormality on the test it's more likely it will be a false-positive result," she said. "But an abnormal result, whether it's a false positive or true positive, generally leads to additional testing, and it's the additional tests that could have some risk."

While ECGs - sometimes called EKGs - themselves are safe, non-invasive and run for about $50, the follow-up tests can involve passing a tube through the heart or other more intensive, costly procedures.

The new recommendations are an update of the USPSTF's 2004 guidelines, which also called for no screening in low-risk adults and said there was insufficient evidence to assess the risks and benefits for screening intermediate- and high-risk people.

Heart disease causes almost one in four deaths in the U.S., according to the Centers for Disease Control and Prevention. In 2008, coronary heart disease in particular killed over 400,000 Americans. The disease is caused by build-up of plaque in the arteries that bring blood to the heart.

Dr. Rita Redberg, a cardiologist at the University of California, San Francisco and editor of the journal Archives of Internal Medicine, said labeling someone as having heart disease when they have no symptoms can also be a problem, and is another downside of screening healthy adults.

"If you're feeling well and don't have heart disease and your doctor is suggesting getting a resting or a stress ECG, have a good discussion about what would be the benefits for you," Redberg, who wasn't involved in the new paper, told Reuters Health.

"This document is certainly suggesting that there aren't any."

Melnikow said instead of asking for tests, people concerned about their heart health can discuss diet, lifestyle and family history risks with their doctor. Then, the doctor can use a risk calculator to determine their chance of getting heart disease - and treat them appropriately.

"Everyone can benefit from being physically active," she said. "Everyone can benefit from not smoking, and people can discuss with their doctors whether they could benefit from taking medication to lower their blood pressure or lower their cholesterol."