Cardiac (Heart) Late Effects

Most childhood cancer survivors do not experience heart problems as a result of their therapy. But certain treatments for childhood cancer may lead to heart disease later in life.

How the heart works

The heart is a muscular organ that pumps blood to the body’s organs. The heart is at the center of the circulatory system, which is made up of a network of blood vessels, such as arteries, veins, and capillaries.

An electrical system controls the heart and uses electrical signals to contract the heart's walls. When the walls contract, the heart pumps blood. Inlet and outlet valves in the heart chambers keep the blood flowing in the correct direction.

A healthy heart supplies the body with the right amount of blood at the rate needed to work well. If disease or injury weakens the heart, the organs won't get enough blood to work correctly.

Cancer treatments that can cause heart problems

Treatments including anthracycline medicines and chest radiation may lead to heart disease in childhood cancer survivors. Nearly 60 percent of all survivors of childhood cancer have had exposure to either anthracycline chemotherapy, chest radiation, or both.

Anthracyclines

Anthracyclines include:

• Doxorubicin (Adriamycin®)
• Daunorubicin/ daunomycin (Cerubidine®)
• Idarubicin (Idamycin®)
• Mitoxantrone (Novantrone®)
• Epirubicin

The risk of developing congestive heart failure increases with the amount of medicine given (dosage):

Chest radiation

Radiation that includes the heart in the area of treatment increases the risk of developing certain heart conditions.

The risk increases with the amount of chest radiation given (dosage).

Anthracyclines and chest radiation

Survivors who received both anthracyclines and chest radiation have the highest risk.

Other risk factors

Heart disease runs in some families.

Women after menopause have an increased risk.

Other health conditions may increase the risk of heart problems:

• Obesity
• High blood pressure
• High cholesterol or triglyceride levels in the blood
• Diabetes

Certain cancer treatments can increase the risk that survivors will develop these health conditions.

Heart problems that may occur

• Heart muscle weakening (cardiomyopathy)
  
• Coronary artery disease
• Stroke
• Abnormal heart rhythms (arrhythmia)
• Problems with heart valves (valvular stenosis or insufficiency)
• Problems with the membrane surrounding the heart (pericarditis or pericardial fibrosis)

Cardiomyopathy can progress over time and lead to heart failure. Other heart conditions can also lead to heart failure. This condition means the heart can’t pump enough blood to meet the body’s needs.

Signs and symptoms

• At first, survivors may not have symptoms, but heart disease may be present. Heart tests such as an echocardiogram (echo) are the only ways to detect heart disease at this point.

• As the heart disease progresses patients may have:
  • Shortness of breath
  • Dizziness
  • Lightheadedness
  • Fainting
  • Severe fatigue
  • Chest pain; sweating, nausea, or shortness of breath with chest pain
  • Swollen feet and ankles
  • Coughing and wheezing that doesn’t go away
  • Heart racing or throbbing
  • Irregular heartbeat

Cardiovascular Risk Calculator

What survivors can do

Cancer survivors can take steps to maintain heart health:

• Know your risk of developing heart problems. Ask your doctor if you have received treatments that increase your risk for heart disease.
• Have regular check-ups that include tests to check for heart problems.
• Share a copy of your Survivorship Care Plan, which includes a treatment summary, with health care providers.
• Consult with a cardiologist if there is evidence of heart disease.
• Lead a healthy lifestyle to prevent heart disease.
• Treat conditions that affect heart health.

Heart-healthy habits

Some lifestyle habits increase the risk of heart disease. These include lack of physical exercise and an unhealthy diet.

Habits that lessen heart disease risk:

• Regular exercise
• A healthy diet
• Not smoking

Exercise and eating a healthy diet can lessen the risk of developing these conditions. Everyone should lead a healthy lifestyle, but it is particularly important for cancer survivors who already have an increased risk of developing heart disease.