Atrial fibrillation is thought to start in the large veins that bring blood from the lungs to the left atrium of the heart (called the pulmonary veins).
Once the catheters are in the left atrium, they destroy some of the tissue where the pulmonary veins enter the left atrium. This prevents the abnormal heart beats that start deep in these veins from reaching the left atrium and causing the atrial fibrillation.
Cardiac ablation works to treat atrial fibrillation in about 70 to 80% of cases (about 7 to 8 out of 10 people) the first time it’s done. If it doesn’t work the first time, your doctor may want you to have the procedure again as it often works better the second time.