Learn the signs of heart damage from cancer treatment

For some patients who’ve undergone specific types of cancer treatment, it may seem like entering remission is a sign that they’ve reached the finish line. But the process of receiving certain anti-cancer therapies can create unintended problems in the heart and cardiovascular system during treatment and in the years that follow.

Chemo and other cancer treatments can cause heart problems

Chemotherapy, targeted therapies, radiation and immunotherapies can truly be lifesavers for patients with cancer. But in the pursuit of eliminating cancer cells, these anti-cancer therapies can create an unintended side effect called “cardiotoxicity,” or heart damage caused by treatment.

“We see many patients during cancer treatment who have changes in heart muscle function (cardiomyopathy) and changes in ischemia (coronary artery disease). Patients can develop electrical disturbances in the heart, and certain types of targeted therapy can increase the risks of atrial fibrillation and valve disease. Plus, the cancer itself can create heart problems,” said Dr. Suparna Clasen, medical director of cardio-oncology at IU Health and director of clinical research operations at the Krannert Cardiovascular Research Center at the IU School of Medicine. “A lot of my research focuses on looking for early or aggressive CV disease among patients who’ve undergone cancer treatment.”

When anti-cancer therapies can cause heart problems

It’s important to monitor the heart and understand the risks cancer treatment poses at every stage of care. Cardio-oncology specialists like Drs. Clasen and Abhishek Khemka monitor patients for heart and blood vessel problems at three stages of their care:

1. Patients who are already at risk for heart problems. When a patient with cancer begins treatment with an increased risk of developing cardiovascular disease (CVD), such as those with hypertension, high cholesterol, diabetes, tobacco use, obesity, sleep apnea and kidney disease, they will be monitored throughout their care. Their care teams will work with patients to optimize their cardiovascular care as much as possible throughout their cancer journey to reduce the likelihood of developing heart problems.
   
   
2. Patients who develop CVD during cancer treatment. If a patient develops problems like heart failure or coronary artery disease during treatment, the doctor will work with the patient to manage CVD in partnership with the medical oncologist, radiation oncologist and other specialists involved in care. Patients can also develop cardiac risk factors during treatment, such as high blood pressure or diabetes, which lead to CVD later.
   
   
3. Patients who develop CVD after cancer treatment is complete. As treatments improve and more patients live longer after cancer diagnoses, they can experience late side effects from anti-cancer therapy. For example, a patient who receives high doses of radiation therapy to the chest may experience symptoms of heart or valvular disease decades after their initial exposure.

Depending on the type of anti-cancer therapy used, patients may be a good candidate for a clinical trial to help researchers better understand the effects on the heart.

“We are currently enrolling patients into various clinical trials based on their oncology exposure. For example, we have a clinical trial for people who treated with these amazing miracle drugs called immune checkpoint inhibitors. These drugs have really changed the landscape of anti-cancer therapy and saved countless lives, but a very small percentage of patients go on to develop something quite catastrophic, like myocarditis or inflammation of the heart muscle,” Dr. Clasen said. “We want people to have access to as many treatment options as they need, but we also want to catch those rare but quite severe side effects.”

Anti-cancer therapies that can cause cardiotoxicity include:

• Chemotherapy, such as anthracyclines, cisplatin, and others
• Immunotherapy, such as immune checkpoint inhibitors
• Targeted therapy, such as HER-2 and VEGF inhibitors
• Hormone therapy, such as androgen deprivation therapy
• Radiation therapy directed at the chest (including areas around breasts, lungs, esophagus and chest lymph nodes)

Symptoms of heart damage from cancer treatment

People can develop symptoms of CVD, or they can present with no symptoms at all, such as a patient who feels fine despite having high blood pressure or uncontrolled sugars. It’s important to continue the care plan provided by the oncologist and maintain follow-up appointments with a primary care physician to monitor for late or long-term cardiovascular problems. Patients should also keep an eye out for new concerns.

Symptoms of heart problems can include:

• Shortness of breath
• Chest discomfort
• Swelling in legs or feet
• Difficulty lying flat at night
• Getting winded more than usual
• Swelling in legs, ankles or abdomen

Patients who experience chest pain, unconsciousness, breathing problems or rapidly increasing symptoms should seek emergency care and follow up with their primary care provider or oncologist.

Preventing heart disease

While cardiotoxicity is unavoidable in some cancer treatments, there are steps patients can take after treatment is complete to lower the risk of developing CVD, such as coronary artery disease, congestive heart failure, arrhythmias, cardiopulmonary disease, valve disease and pericardial disease.

By focusing on cardiometabolic health, or how patients feed and fuel their body, they can manage risk factors for CVD. Aside from unavoidable risks like cardiotoxicity from cancer treatment, nearly all of CVD is preventable. One way to remember how to improve cardiometabolic health is through “ABCDE”:

• Awareness of your risk factors and lifestyle choices, such as family history, and abstain from tobacco and excessive alcohol use
• Blood pressure monitoring
• Cholesterol monitoring
• Diabetes management
• Exercise

Much follow-up care provided by cardio-oncologists involves educating patients on these risk factors and helping them find ways to modify their lifestyles to create more healthy habits following cancer treatment.

Through increased awareness of the risk factors of cardiotoxicity in cancer treatment and the benefits of cardiometabolic health, patients who are undergoing cancer care or survivorship can lessen the odds of CVD throughout their lives.