Question: Massachusetts Subscriber Answer: Remember that CPT guidelines state that you must report a Category III code when it's available for a service -- reporting an unlisted Category I code instead would be incorrect. The benefit of reporting a Category III code is that the AMA uses the codes to gather usage data which may encourage the CPT panel to create a Category I code for the service. Bonus tip: You shouldn't append modifiers 26 (Professional component) and TC (Technical component) to these codes. If the cardiologist provides the global service, report 0178T (... with interpretation and report). If a facility performs the technical component and the cardiologist performs interpretation and report only, you should assign 0180T (... interpretation and report only) for the cardiologist. The facility would report 0179T (... tracing and graphics only, without interpretation and report).