Side Effect: Atrial Fibrillation

• Atrial fibrillation (often called “AFib”) is a type of arrhythmia, or irregular heartbeat, that originates in the atria, the upper chambers of the heart.
• AFib is a problem when the atria quiver instead of contracting effectively, which can lead to a fast and irregular heartbeat (also known an abnormal rate and abnormal rhythym).
• According to the American Heart Association, AFib affects between 2.7 and 6.1 million Americans, and its prevalence is expected to increase as the population ages.

Symptoms of AFib can include:

• heart palpitations (an often uncomfortable and noticeable feeling in your chest from your heart beating too fast)
• shortness of breath
• chest pain or pressure
• weakness
• fatigue
• dizziness

Some people with AFib may not experience any symptoms at all. To determine if you have AFib, your doctor will order a non-invasive test called an electrocardiogram (also known as an ECG or EKG) to measure the electrical signals from your heart.

• AFib can occur in people of all ages, but it is more common in adults older than 65 and in people with underlying heart conditions, such as high blood pressure, heart failure, or coronary artery disease.
• Cancer and cancer treatment can also put patients at an increased risk.
  • Research has shown that the likelihood of experiencing AFib is 2.3 times greater in patients with cancer, and those with colon, prostate, lung, and breast cancers are at highest risk for developing this heart condition.

The following chemotherapy agents are also known to increase the risk of AFib:

• Daunorubicin
• Doxorubicin
• Cisplatin
• Cyclophosphamide
• Capecitabine
• Fluorouracil (5-FU)
• Rituximab
• Cetuximab
• Romidepsin
• Lenalidomide
• Bortezomib
• Ibrutinib
• Ponatinib
• Sorafenib
• Sunitinib
• Paclitaxel
• Docetaxel

• Not all cases of AFib can be prevented. However, it can help to control underlying risk factors such as high blood pressure and diabetes.
• You can also lower your overall risk by avoiding triggers such as excessive alcohol intake, smoking, and stress.
• Eating a heart-healthy diet and remaining physically active can also help prevent it from developing.

Treatment for AFib may depend on the type and stage of cancer, as well as your overall health status. Options may include medications such as:

• Beta blockers to slow the heart rate
  • Examples include: metoprolol, propranolol
• Calcium channel blockers to slow the heart rate
  • Examples include: diltiazem, verapamil

These medications are intended to reduce the risk of blood clots by restoring your heart’s ability to pump blood more effectively. Importantly, these medictions may interact with other medications you are taking so ask a pharmacist before you start them to reduce the risk of side effects.

• If your risk of a blood clot (and stroke) are high despite taking heart rate and heart rhythm medications, your physician may also prescribe a blood thinner such as warfarin, apixaban, rivaroxaban, or dabigatran, to reduce the risk of clotting.
  • Procedures, such as cardioversion, to restore normal heart rhythm or catheter ablation, to destroy any abnormal tissue causing AFib, might also be considered.
  • In more severe cases a pacemaker might be required to help your heart maintain a normal rhythm.