Yes, you should read up on catheter ablation. It is mechanically scarring the tissue lining the left atrium, and the idea is to leave scars around the pulmonary veins where they exit into the rear wall of the atrium. That is where 90% of all AF comes from...incursions of atrial endothelial tissue into the mouths of the four veins (two from each lung). That tissue helps to transmit electrical signals that get into the veins and the result is more beats than there should be. The ablation procedure is done through the femoral vein, near your groin, and they run the catheter up into the right atrium. They pierce the septum between the two atria, and run a small needle at the end of the catheter up against the mouths of those veins and begin to make many spot burns using radio frequency. Those burns will heal over several weeks of what is called the 'blanking period', but what remains is scarred tissue. The electrical impulsed can't run over or through the scarred tissue, so they become dammed, or blocked. End of atrial fibrillation!