An issue was published in Coding Clinic, Third Quarter 2014 regarding a modified left atrial Maze procedure performed during a coronary artery bypass graft surgery. The published advice was to assign code 02570ZK, Destruction of left atrial appendage, open approach, to capture the Maze procedure. In light of the advice published in Fourth Quarter 2014, what is the correct body part value when the left atrium is ablated during an open maze procedure, the left atrium or the conduction mechanism?
The conduction mechanism is the pathway for the electrical impulses throughout the heart that govern cardiac rhythm, whereas the left atrium is one of four muscular chambers of the heart. The ablation procedure is directed at the pathway for electrical impulses rather the muscular wall of the heart itself. The atrium is not being destroyed.
Code 02580ZZ, Destruction of conduction mechanism, open approach, is the correct code assignment for the modified left atrial Maze procedure. The focus of the procedure is ablation of the conduction mechanism (aberrant arrhythmia), not ablation of the atrial muscle. The part that is being treated is the conduction mechanism (electrical pathway), and it is the correct body part rather than atrium or atrial appendage. The Maze procedure and other types of ablative procedures performed in the electrophysiologic laboratory relate to the conduction mechanism, which involves various parts of the heart, including the atria.
According to the ICD-10-PCS guidelines, physicians are not required to use the terminology in PCS. Guideline A11 says, “Many of the terms used to construct PCS codes are defined within the system. It is the coder’s responsibility to determine what the documentation in the medical record equates to in the PCS definitions. The physician is not expected to use the terms used in PCS code descriptions, nor is the coder required to query the physician when the correlation between the documentation and the defined PCS terms is clear.”