How can therapy for heart attack patients help cancer survivors?

Heart disease and cancer – ruthless conditions that are the nation's leading causes of death – can sometimes intertwine. Certain cancer treatments can directly damage the heart, while others leave survivors dealing with weight gain or loss of fitness.

One way to potentially counteract these heart-related risks is to adopt a cardiac rehab plan like the one heart attack survivors follow.

That's the strategy behind cardio-oncology rehabilitation, an emerging health care specialty that could be instrumental in treating the cardiovascular-related problems that arise in cancer survivors, according to a new scientific statement from the American Heart Association published Monday in the journal Circulation.

Thanks to advances in early detection and treatment, there are nearly 17 million cancer survivors in the United States. But many are 1.3 to 3.6 times more likely to die from a cardiovascular-related event compared to someone who has never had cancer. Cancer survivors also are 1.7 to 18.5 times more likely to develop diabetes, high blood pressure, high cholesterol or other heart disease risks.

"There are still cancer patients and health care providers who don't understand the link between heart disease and cancer, so we're trying to educate them," said Dr. Susan Gilchrist, chair of the statement's writing committee and a cardiologist at the University of Texas MD Anderson Cancer Center in Houston.

The new report explains how certain factors – such as a patient's age, the type of cancer and whether chemotherapy was involved – can make a difference in a person's risk for cardiovascular disease, she said.

"We need to do a better job of explaining the issue, and I think this document helps people understand who's at higher risk and, if they are at higher risk, what can we do about it as both oncologists and cardiologists so we don't keep separate silos," Gilchrist said.

Cardiovascular risks go up for cancer survivors for various reasons. Some people already may have cardiovascular risk factors, but not know about them at the time of their cancer diagnosis or during treatment.

Other times, the heart muscle is weakened by the drugs, radiation or other treatments used to eliminate the cancer.

"Many patients, after they receive their cancer therapy, need help getting their heart back to a stronger and healthier functional status," said Dr. Randal Thomas, a member of the statement's writing committee.

That's where cardiac rehabilitation comes into play.

Cardiac rehab is a medically supervised program for people who have had a heart attack or some type of heart surgery. It involves exercise training, education about lifestyle changes and counseling to help reduce stress and anxiety.

"Cardiac rehab is a great way to systematically alter the lifestyles, particularly exercise, and cardiovascular risk factors at play for a cancer patient," Gilchrist said. "And cardiac rehab already exists – you don't have to re-invent the wheel. It exists all across the United States, both in community and academic hospitals."

But because cardio-oncology rehab is an evolving field that has only existed for a handful of years, getting insurance to pay for it has been a problem.

"This scientific statement is a first step to pave the way for reimbursement for patients with cancer within the (cardiac rehab) model," its authors wrote.

The statement also calls for more research to show cardio-oncology rehabilitation works. Past studies have shown exercise may help people regain some of the cardiorespiratory fitness lost during cancer treatment. Research also suggests programs modeled after cardiac rehab can improve a survivor's muscular strength and quality of life.

"There's definitely a need for more studies to look at new populations and methods and when is the best time to initiate therapy," said Thomas, medical director of the cardiac rehabilitation program at the Mayo Clinic in Rochester, Minnesota, where a cardio-oncology rehab program is currently available for breast cancer survivors.

"But at the same time, it's a really good time for patients and health care providers to communicate with policymakers, including government leaders, about the importance of covering what we already know can be beneficial to patients recovering from cancer."

Gilchrist, who heads up one of the nation's few programs in this area, said there's an overlap between cardiovascular disease and factors that drive cancer.

"Cardiac rehab is about getting people to exercise more. We know exercise helps people live longer. It keeps people out of the hospital. It lowers the risk of cancer mortality for several types of cancer. It also prevents cardiovascular disease," she said. "So providing structured exercise to cancer patients, systematically across the U.S., would be a tremendous win for society in general."