thoracodorsal artery perforator flap CPT

Any suggestions for coding a pedicled thoracodorsal artery perforator flap? This procedure was performed in order to repair the site following excision of a 13 x 10 cm axillary tumor. What is confounding me is the pedicled artery flap, as I have only coded muscled flap closures...Thank you SO much for any insight!