 After that, I go across. This is called drive-through procedure, where I do the right flutter ablation, which not everybody does. Just like McDonald's. Then I go across the septum, which is the wall between the top chambers, poke a little hole that closes on its own, nothing to worry about. It's how we do this procedure. Come into the left upper chamber, go into those veins, and I freeze in those veins using cryo-balloon ablation.