Blood vessel damage from treatment

Coronary artery disease and atherosclerosis. The interiors of healthy blood vessels are usually smooth, but radiation can roughen them inside. These rough spots provide sites for fatty deposits (plaques) to develop in coronary arteries and other arteries and veins. Calcium deposits can harden the plaques, resulting in atherosclerosis (hardening of the arteries). When this happens in the coronary arteries in the heart, it is called coronary artery disease.

Survivors of Hodgkin lymphoma have been studied extensively due to the risk of vascular injury in the field of radiation (e.g., carotid arteries in the neck). An inflammatory process that damages the endothelial lining of the blood vessels is suspected. In these studies, survivors of Hodgkin lymphoma who did not have neck irradiation also had increased premature carotid artery disease, and the reason is not yet understood.

Atherosclerosis can cause three problems:

1) The fatty deposits narrow the blood vessels, reducing flow of blood.

2) Layers of plaque decrease the strength and elasticity of the arteries.

3) Plaques roughen the lining of the vessel, allowing platelets to form clots at the rough spots.

If a clot breaks free, it can block blood flow in narrow arteries, reducing or stopping the supply of oxygen to that area. When oxygen is slowed to areas of the heart, angina (chest pain) results. If the clot blocks a coronary artery completely, it causes a heart attack.

Healthy lifestyle can make a difference

The tendency to develop atherosclerosis is related not only to treatment for childhood cancer, but also to family history, weight, and lifestyle choices such as diet, exercise, and smoking.

• Smoking vastly increases the risk of heart disease. The nicotine in cigarettes increases the heart rate and accelerates plaque formation that narrows arteries. It also damages the lungs, reducing their efficiency. Consequently, the heart must pump faster to deliver adequate oxygen to the cells of the body. Vaping is more intense than smoking.

• A diet high in saturated fat can lead to high levels of cholesterol. This can increase the chance of developing fatty deposits in the arteries, making a heart attack or stroke more likely. Health experts now suggest eating as little dietary cholesterol as you can, under 300 milligrams (mg) a day (see below for foods recommended for a heart healthy diet).

• Exercise helps maintain a healthy weight, increases lung capacity, and strengthens body muscles, including the heart. A note of caution is that if you received anthracyclines or radiation to the heart, you should consult your follow-up healthcare provider prior to starting an exercise program.

• High blood pressure based on your age (any blood pressure greater than 140/90) is a risk factor for heart disease and promotes atherosclerosis. High blood pressure is the initial sign of heart changes. Your physician may prescribe medications to lower your blood pressure.

A healthcare provider who specializes in treating survivors of childhood cancer cautions:

A significant problem that we are just beginning to understand is the effect of cranial radiation and chemotherapy in promoting premature coronary artery disease. Leukemia (ALL) survivors, especially those treated with cranial radiation, have an increased incidence of obesity and are more likely to be physically inactive. Obesity and physical inactivity at a young age are significant risk factors for the development of high blood pressure, diabetes, and dyslipidemia (high LDL cholesterol, low HDL cholesterol, high triglycerides) and these aid in the development of premature coronary artery disease. Because of this, it is essential that survivors exercise, eat a prudent diet, and get regular follow-up.

Activities you can do to help slow the atherosclerotic process and keep blood pressure low include:

• Eat a diet low in saturated fats, cholesterol, salt, and processed foods with reduced amount of meat, poultry, dairy products (except for low-fat yogurt and kefir), limit whole eggs (use egg-whites or egg substitutes).

• Eat more whole grain breads, oats, bran, fruits, and vegetables.

• Eat foods high in fiber, such as potatoes, turnips, sweet potatoes, peas, beans (especially black beans), lentils, and nuts (almonds, walnuts, pistachios).

• Exercise regularly (30 minutes every day).

• Keep body fat low and monitor your body mass index (BMI) with your health care provider. BMI is a screening tool based on height and weight that helps health care providers evaluate weight categories that may lead to health problems.

• Limit alcohol intake (including beer).

Medical problems such as hypothyroidism, high blood pressure, high cholesterol, and diabetes can increase your risk of developing atherosclerosis.

Raynaud’s phenomenon can also develop in long-term survivors with vascular disease. This is when the fingers and toes become white or bluish due to spasms of the arteries leading to the hands. It is usually precipitated by cold or emotion, and affected individuals often have a genetic predisposition for developing Raynaud’s. This may also occur in survivors treated with vincristine/bleomycin. The condition is usually chronic, but it may improve slowly over several years in some survivors.

Signs and symptoms of coronary artery disease/heart attack

Coronary artery disease. Risk of coronary artery disease and heart attack is lower for patients who had lower doses of radiation using modern techniques, and higher for patients treated with high doses of radiation and no heart shielding.

Signs and symptoms of coronary artery disease are as follows:

• Chest pain (or pressure-like sensation)

• Chest, neck, or jaw pain upon exertion

• Indigestion upon exertion

• Shortness of breath upon exertion

Heart attack and decreased oxygen. Symptoms of inadequate oxygen to the heart and heart attack are as follows:

• Crushing chest pain

• Pain or numbness down the left arm

• Shortness of breath

• Sweating

• Nausea

• Feelings of impending doom

Many of these signs and symptoms can be caused by other illnesses or conditions; however, it is prudent to get an evaluation if any of these symptoms are present. Do not ignore any of these symptoms; seek medical attention right away.

Screening and detection for coronary artery disease

Screening and detection for coronary artery disease includes some of the tests described above for the heart. A stress test is also needed. Routine cholesterol screening for those at risk for coronary artery disease is also essential.

Medical and surgical management

Medical management should involve frequent surveillance for symptoms in at-risk survivors. You and your healthcare provider should refer to the guidelines and recommended screening schedules online at: Children’s Oncology Group, Long-Term Follow-Up Guidelines for Survivors of Child, Adolescent, and Young Adult Cancers, V6 (Oct 2023). See Resources for website and link.

A variety of medications and lifestyle modifications are used to treat coronary artery disease. Advanced coronary artery disease is sometimes treated with a coronary artery bypass graft (open heart surgery) or balloon dilation angioplasty.