Question: How do pacemakers help prevent atrial fibrillation? Answer :There was a lot of hope a number of years ago that pacemakers would prove to be an effective treatment for atrial fibrillation. But in fact they're very ineffective, and they do not treat atrial fibrillation. There's only one situation where pacemakers play an important role in patients with atrial fibrillation, and that is in patients who have both atrial fibrillation and they have slow heart rhythms.