Ask Dr. Z

I have a couple of ablation cases that are confusing to me and wonder if these should be considered unlisted codes or if they are like the other ablations and are diagnosis-driven. I have one case that is left atrial and right atrial ablation for numerous atrial macroreentrant atrial flutters, vein of Marshall alcohol ablation for mitral isthmus-dependent flutter, antral pulmonary vein isolation, and CAFE ablation for atrial fibrillation. The other case is an epicardial ablation with a subxyphoid access for VT. My question is, do we use unlisted codes for the alcohol ablation and the epicardial ablation to capture the extra work ? Or should I consider using a -22 modifier?