Radiofrequency catheter ablation may be used to treat atrial fibrillation in those who do not respond to treatment with medication or electrical cardioversion. During this procedure, a thin catheter is inserted in a blood vessel and the end is threaded into the heart. The catheter tip can generate electrical current and heat. The cardiologist performing the procedure uses the catheter to make pinpoint burns in the tissue on the inside surface of the heart. The pinpoint burns interrupt the electric signals from the tissue that cause atrial fibrillation.

The same procedure is used to perform pulmonary vein ablation, which also treats atrial fibrillation. In this case, the atrial fibrillation originates from tissues inside the pulmonary vein.