The chemotherapy that Karen Zucker received following breast cancer surgery helped her beat back the disease. But it also injured her heart.
If left untreated, the damage to her heart — a well-known side effect of chemotherapy in some patients — would have shortened her life as surely as her cancer.
"I was at a point where I was out of breath just walking," Zucker, 53, said of her stamina, which weakened as she underwent chemotherapy following a double mastectomy. "I thought it was my lungs."
Her doctors at UConn Health in Farmington quickly set the record straight when tests showed it was her heart that was failing.
The cardio-toxic effects of chemotherapy, while considered rare by medical experts, can be devastating for some cancer patients. Chemotherapy can weaken heart muscle, alter normal heart rhythms, increase blood pressure or cause coronary artery spasms that could trigger a heart attack.
The cardiac risks of chemotherapy and radiation have been recognized for decades but when measured against the more devastating potential of cancer, they seemed until recently medically less important.
"In the past if you were given a diagnosis of cancer, it was almost like a death sentence," said Dr. Agnes Kim, a cardiologist who heads the cardio-oncology program at UConn Health. "The long-term side effects kind of took second place."
With the advent of better cancer treatments, women are living longer and thus safeguarding their hearts has become an added concern.
"Now we have a lot of cancer survivors, and the side effects are very important, especially the cardiac side effects," Kim said. "You can be a cancer survivor, then be a heart failure patient. That's what we are trying to prevent."
Kim is a member of the team of cardiologists, oncologists and surgeons who treated Zucker. While studying to become a cardiologist, Kim, relying on personal initiative, added the relatively new field of cardio-oncology that focuses on heart disease, cancer and their treatment to her studies.
"A lot of it I had to learn on my own and by talking with oncologists," Kim said.
Cardio-oncology, a medical discipline that's come of age in the past five or so years, is the study of the relationship between cancer, cancer treatment and heart disease, Kim said. The higher incidence of heart disease among cancer survivors led to the growth of this specialty.
When Kim arrived at UConn Health in 2014, there was no formal cardio-oncology program so she helped launch a cardio-oncology clinic. She is now the director. There are two such clinics in the state that are recognized by the American College of Cardiology (ACC). The second is at Smilow Cancer Hospital at Yale New Haven Health in New Haven.
If there were ever a cancer patient likely to develop cardiac problems stemming from her cancer treatment, it would be Karen Zucker.
Zucker, a biomedical researcher at UConn Health who lives in Newington, was 18 when she was diagnosed with Hodgkin's lymphoma, a cancer of the lymphatic system, which is part of the body's immune system. Her treatment included radiation therapy that zapped the lymphoma cancer but also affected her heart.
"My lungs were radiated, my breasts were radiated," Zucker said. This put her heart in the direct line of fire of the radiation.
"They have found now through research that girls, especially in their young 20s, that because of the radiation they became a very high risk for breast cancer," Zucker said. Lacking any of the genetic risk factors for the disease, Zucker suspects that the radiation led to her developing breast cancer, which was discovered during a routine mammogram in December 2015.
Aware of the increased risk to Zucker's heart that chemotherapy could pose, Kim with Dr. Susan Tannenbaum, chief of hematology and oncology, and Dr. Karen Hook, a hematology and oncology specialist, devised a treatment plan that included closely monitoring the output of Zucker's heart before, during and after her chemotherapy.
When Zucker's heart showed signs of weakening due to the cancer treatment, a result made more likely because of the earlier radiation treatment, the team adjusted the chemotherapy dosage and added two cardiac medications typically given to patients with heart disease. These helped restore much of the heart function Zucker had lost during treatment and enabled her to take aqua-therapy at the Hospital for Special Care in New Britain.
An article published last year in the American Cancer Society's CA: A Cancer Journal for Clinicians, reported that a comprehensive review of breast cancer survivors in the United States found that these women had a "significantly increased risk of death caused by CVD (cardiovascular disease) exceeding their risk of death from the initial cancer or from recurrent disease."
"…CVD is not always caused by toxicity from cancer therapy exposures, and it can be a normal disease process in older adults. However, the impact of cancer therapies on CVD in the general adult cancer population is largely unknown."
That unknown is the risk that patients like Zucker must accept. The risk also is growing rapidly.
Kim said there are "thousands of new cancer drugs that are being developed and FDA approved" and with them comes a "potential for cardiac toxicity as well."
Though the radiation therapy Zucker had 35 years ago in 1982 took out the immediate threat of Hodgkin's lymphoma, it likely triggered a genetic mutation that led to her developing breast cancer by 2015. Without the radiation treatments she would not have lived for long.
"If I had had that 10 years earlier, they said, there wouldn't have been anything they could have done for me," said Zucker, who enjoys flower gardening and bird watching in her spare time. "I would have died."
Fast forward to today and consider the potential harm chemotherapy will cause to some hearts and weigh that against the harm caused by breast cancer. What will they say 35 years from now about today's chemotherapies, all of which are toxic, more or less, to the heart?
"You could look back and say they made the wrong call," Zucker said, referring to the full-chest radiation treatments she received. "But that's all they had then."
In the past, cancer patients "were basically treated and left alone and many years down the road they were developing heart failure," Kim said. "If you catch this cardiac dysfunction during treatment or right after treatment and you start them on cardiac medications right away, you can prevent heart failure."