We have started receiving denials from Aetna Medicare when billing out ERCP w/ stent removal (43275) and ERCP w/ stone removal (43264). We have appealed several claims and explained the difference in the procedures performed. ICD Z46.59 is billed with the stent removal and ICD K80.50 is willed the stone removal. Is anyone else having this problem getting payment from Aetna Medicare. Any help is appreciated.