Treatment for chaotic heartbeat

Dear Dr. Roach: I am a 72-year-old man. I thought I was in excellent health until I was diagnosed with atrial fibrillation in a routine physical exam with an EKG about six months ago. I was and continue to be asymptomatic. I am 6 feet, 1 inch tall and weigh 173 pounds. I do weight training and stretches at the gym two or three times each week and get cardio exercise by bicycling. My resting heart rate is always around 50.

My family physician prescribed 120 mg of diltiazem. I take aspirin 325 mg. The diltiazem was later reduced to 30 mg. In both cases it produced unwelcome side effects. The cardiologist took me off all medications (except aspirin) and said to limit my physical activity. Although I feel good and seem to have no other health issues, I am concerned. — D.B.

Atrial fibrillation is an abnormal heart condition where the normal rhythm is replaced by a chaotic and unpredictable heartbeat. Atrial fibrillation is treated with either “rhythm control” or “rate control,” in addition to reducing risk of stroke, which is elevated in all people with AFib. Rhythm control uses electricity or medications to try to return the heart to normal rhythm. In rate control, the person is allowed to stay in AFib, but medications are given to keep the heart rate from going too fast, if necessary. It doesn’t seem to be necessary in you. It sounds like the cardiologist reached the conclusion that the side effects from diltiazem were not worth a bit of protection from a fast heart rate. Protection from stroke is still important to consider. A cardiologist will look at an individual’s risk for stroke (one tool for doing so is the CHADS-VASc score). While most people will need to be on a powerful medicine like warfarin or apixaban (Eliquis), some people are at low-enough risk that aspirin alone is sufficient. It sounds like aspirin alone is appropriate for you.