Afib: Rhythm or rate control

Ask the doctor

Q. I was diagnosed with atrial fibrillation and my cardiologist prescribed metoprolol [Lopressor], which I understand is also used to treat angina. But I rarely have any chest pain. I was wondering if I should instead be getting another kind of medication to treat my condition?

A. During a bout of atrial fibrillation (afib), the heart beats very rapidly and irregularly. As a result, the heart may not pump effectively, which may cause symptoms such as breathlessness and fatigue. These episodes may be occasional and fleeting, or they may last hours, days, months, or even years.