Cancer treatment linked to cardiac issues

Chemotherapy, radiation and other targeted cancer treatments are lifesaving measures for many patients. But what doctors are discovering now is these treatments are wreaking havoc on cancer survivors’ hearts. 

Thirty years ago this wasn’t a big issue because survival rates for cancer weren’t nearly as high as they are now. A 2014 report by the American Cancer Society, in collaboration with the National Cancer Institute, estimated there are almost 14.5 million cancer survivors alive in the U.S., and that number is expected to grow to almost 19 million by 2024.

That means more and more cancer patients are going into long-term remission or are being cured, and living longer lives. So now doctors are having to treat survivors for damage their life-saving treatments inflicted.

“It’s a major set of issues that weren’t a problem 30 years ago, because we didn’t have that many survivors,” said Dr. Steven Lipshultz, chief pediatrician at Children’s Hospital of Michigan, in a US News article.

New specialty

To combat this problem, two of the biggest specialties have joined together. Cardiologist and oncologists are creating “cardio-oncology” clinics where their focus is to identify types of cancer patients most likely to suffer heart damage from their treatments.

What the doctors at these clinics have found is that when a specific class of cancer-fighting agents – anthracyclines – combine with iron they form molecules that create holes in heart cells permanently damaging large areas of tissue setting the stage for heart failure.

To combat this, doctors give the drug dexrazoxane which, according to the US News story, “locks up iron and carriers it out of circulation during chemotherapy.” When patients get dexrazoxane the number of dead and dying heart cells is dramatically reduced, noted Dr. Lipshultz.

Sounds great right?

It’s a step in the right direction, but according to the experts cardio-protective drugs are “an imperfect shield” and more studies need to be done.

Childhood cancer patients

One patient population where cardiac problem are cropping up more and more is in adults who’ve had childhood cancers.

As adults they feel great and have a clean bill of health, and then some major event causes physical or psychological stress and the patient has a heart attack.

Problem is you don’t expect to see a 25-year-old patient in your emergency room (ER) who’s having a heart attack so they’re often sent away, noted Dr. Lipshultz. But it’s something that ER docs and nurses have to be more aware of.

Basic guidelines

While cardio-oncology is a major breakthrough and has been spreading in academic research centers, it’s been slow to move through community hospitals – especially on the West Coast – where a large portion of cancer patients are treated every day.

That makes it all the more important for cancer survivors and their doctors to take every step possible to lower their risk for heart failure.

To help survivors out, Vanderbilt University doctors developed an ABCDE checklist patients whose cancer’s in remission and their doctors can use to promote heart health.

The letters stand for:

• Awareness of heart disease symptoms
• Blood pressure control
• Cholesterol lowering and smoking Cessation
• Diet, Diabetes treatment and Dose knowledge of chemotherapy and radiation, and
• Exercise and Echocardiogram heart screening.

“It’s a simple checklist that every patient can remember and every primary care physician can use no matter where they are,” said Dr. Javid Moslehi, director of cardio-oncology at Vanderbilt University Medical Center, in a separate US News article.

What makes all of this challenging is every patient is unique. Not all cancer survivors will develop heart disease, and those who do can exhibit different symptoms to no symptoms at all.

Patients’ risk profiles are based on multiple factors – age, other conditions, chemotherapy dose, chemotherapy type, chest radiation dose and the amount of heart tissue that receives radiation.

Until further research is done, cardiac monitoring at regular intervals (every one to five years) is vital to this patient population’s survival.