Patients who were treated for breast cancer or lymphoma are more than three times at risk of developing congestive heart failure, compared with patients who did not have cancer, finds a study.

Congestive heart failure is when the heart muscle does not pump blood as well as it should. The researchers found that risk of increased heart failure occurred as early as one year after cancer diagnosis, but continued 20 years after patients completed cancer treatment. Overall, one in 10 cancer patients developed heart failure by 20 years after cancer diagnosis. "The majority of patients do not develop heart failure, but our research helps us recognise the factors associated with it and the importance of appropriate heart care following cancer treatment," said lead author Carolyn Larsen, cardiologist at Mayo Clinic -- a US-based non-profit.

"Our research suggests that periodic cardiac imaging to monitor for heart damage may be needed for some cancer patients even if they have no signs of heart damage initially after chemotherapy," Larsen added. For the study, the team tracked heart failure cases in 900 breast cancer and lymphoma patients and 1,550 non-cancer patients. The results revealed that cancer patients were three times as likely to develop heart failure within five years of their diagnosis.

About seven out of every 100 cancer patients developed heart failure. Of those with cancer, patients who were also diabetic or received high doses of a type of chemotherapy called anthracycline had an even higher risk of heart failure. "We discovered that diabetes also was a strong risk factor, but we don't know what happens in the body that makes heart failure more likely in these patients," the researchers noted, emphasising the need for further research. The findings would be presented at the American College of Cardiology's 67^th Annual Scientific Session in Orlando.