Q&A: Could I have atrial fibrillation and not know it?

A: Atrial fibrillation (AFib) is the most common type of abnormal heart rhythm. It occurs when the top chambers of the heart, the atrium, beat too quickly and irregularly.

Symptoms of AFib include having a racing heart or palpitations, being short of breath, generally not feeling well, and being fatigued.

In patients with no symptoms, a doctor might hear the abnormal rhythm when listening to the patient’s heart with a stethoscope.

The most common way to diagnose AFib is with an electrocardiogram (EKG). Doctors might also suspect AFib in some patients with cryptogenic stroke, which is a stroke without an identifiable cause. In these patients, we can implant a small loop recorder device under the skin in the chest to monitor the patient’s heart continuously to check for AFib. A third of patients with cryptogenic stroke are diagnosed with AFib.

Once AFib has been diagnosed, the most important thing to determine is the patient’s risk for stroke. In general, patients with AFib have a five times higher risk of stroke compared with patients without AFib. Other risk factors for stroke include having high blood pressure, diabetes, vascular disease, a prior stroke, or a history of congestive heart failure. Women and those over age 65 are also at greater risk.

If a patient with AFib is found to have a high risk for stroke, we prescribe them blood thinners — known as anticoagulants — to reduce the risk of blood clots. For those who cannot take blood thinners, we can often use a catheter-based procedure to reduce stroke risk. This procedure involves closing the left atrial appendage, which is a sack-like structure that comes off the left atrium, by putting a catheter inside the heart and placing a plug-like device to close it. In addition, minimally invasive surgical procedures are available that close the appendage by placing a loop around it or a clip over it.

In some patients with AFib, we perform an electrical cardioversion. We give the patient an electrical shock on the outside of the chest while he or she is under sedation. The shock can reset the heart to a normal rhythm. After the procedure, most patients are prescribed sodium channel blockers or potassium channel blockers to maintain the proper rhythm and suppress the abnormal electrical signals that cause AFib.

If these options don’t resolve AFib, we can also perform an ablation. During the ablation we insert a catheter through the veins in the groin and move it into the heart to burn specific tissues in the top chamber of the heart that are triggering AFib. The scarring of these heart tissues interrupts the abnormal electrical signals and helps the patient’s heartbeat stay in rhythm.

Devender Akula is a cardiac electrophysiologist at the AtlantiCare Heart & Vascular Institute in Pomona, N.J.