(WASHINGTON) -- The heart attack death of Kara Kennedy, the latest in the tragedy-touched Kennedy dynasty, may have been related to the aggressive cancer treatment she underwent about a decade ago, say her brother and a cardiologist.
The 51-year-old daughter of the late Sen. Edward M. Kennedy died Sept. 16 while working out at her Washington, D.C., gym.
"Depending upon where the lung cancer was, her heart could have taken a direct hit," said Dr. Sharonne N. Hayes, a cardiologist and founder of the Women's Heart Clinic at the Mayo Institute.
More details on Kara Kennedy's death are expected to be released by the Edward M. Kennedy Institute for the United States Senate as funeral arrangements are being made for Wednesday.
Kara Kennedy was diagnosed with lung cancer in 2002 and was initially told it was inoperable. But with her father's help, she found a surgeon at Brigham and Women's Hospital in Boston who removed part of her right lung, followed by chemotherapy and radiation.
Her brother, former Rhode Island Rep. Patrick Kennedy, 44, said the grueling treatments had left his sister physically weakened.
For cancer patients who have aggressive chemotherapy and radiation, particularly in the chest, "there are some real heart risks," according to Hayes, who did not treat Kara Kennedy. "The heart muscle can be weakened."
"This is probably widely underappreciated," she said. "People are so fearful of cancer, but in order to save people from cancer, other organs are put at risk -- the heart, in particular."
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