WASHINGTON, Feb. 1 (Xinhua) -- Some breast cancer therapies may put patients at an increased risk of cardiovascular diseases including heart failure, the American Heart Association (AHA) warned Thursday.

In a scientific statement published in its journal Circulation, the AHA said that breast cancer survivors, especially older women over the age of 65, are more likely to die from cardiovascular disease than breast cancer.

"Any patient who is going to undergo breast cancer treatment, whether they have heart disease at the beginning or not, should be aware of the potential effects of the treatments on their heart," said Laxmi Mehta, chair of the writing group for the new scientific statement.

"This should not deter or scare patients from undergoing breast cancer treatment, but should allow them to make informed decisions with their doctor on the best cancer treatment for them," said Mehta, who is director of the Women's Cardiovascular Health Program and an associate professor of medicine at the Ohio State University.

For example, HER-2 targeted therapies can cause weakening of the heart muscle, a condition known as heart failure.

In some cases, the reduction in heart function is temporary and cessation of the treatment or the addition of heart medicines can improve function, but in some breast cancer patients, heart failure can be permanent, the AHA said.

"Because of this, the early development of heart failure can signal a need to slow down and/or alter a patient's breast cancer treatment because of the risk for worsening the condition or the development of permanent heart failure," it wrote in a press release.

It also noted that administering common chemotherapy agents in new ways may reduce heart disease risks.

Studies have shown that when a chemotherapy drug called doxorubicin is administered slowly, rather than all at once, patients may have a lower risk of heart failure.

In addition, a drug called dexrazoxane that could reduce cell damage has recently been approved for patients with metastatic breast cancer who receive high doses of doxorubicin.

Other treatments, such as radiation, can affect the heart arteries and cause the development of coronary artery disease or blockages, said the AHA.

Some breast cancer treatment agents, such as anthracyclines, can result in abnormal heart rhythms that in some patients are benign but in others can lead to life-threatening heart rhythms.

And, some treatments -- like antimetabolites -- can cause spasm of the heart arteries, which can cause chest pain symptoms but could lead to heart attacks as well.

The AHA said there are lifestyle choices, primarily diet and exercise, that could help decrease the risks of developing both diseases.

About 47.8 million women in the U.S. have cardiovascular diseases, compared with about three million with breast cancer.

According to the AHA, many of these people "regard breast cancer as the primary threat to women's health," so "it is important to recognize the overlap of heart disease and breast cancer as both entities impact survival."