Cardiology Coding Alert

But you can override an MUE when the cardiologist performs and documents a medically necessary number of services that exceed the limit. Check your payer's reporting preference.

HCPCS offers modifier GD (Units of service exceeds medically unlikely edit value and represents reasonable and necessary services). But there is little information available on proper use of this modifier.

A CMS FAQ states that "since each line of a claim is adjudicated separately against the MUE value for the code on that line, the appropriate use of Current Procedural Terminology (CPT) modifiers to report the same code on separate lines of a claim will enable a provider/supplier to report medically reasonable and necessary units of service in excess of an MUE value."

CMS notes that modifiers 76 (Repeat procedure by same physician) and 77 (Repeat procedure by another physician) are among your options, as are the anatomical modifiers, such as RT (Right side). You may also use modifier 59 (Distinct procedural service), but CMS cautions you to use this only if no other modifier is appropriate.

You also may need to supply documentation showing medical necessity for the additional units.

For example, suppose the cardiologist performed percutaneous transluminal coronary angioplasty (PTCA) on four vessels. Code 92982 (Percutaneous transluminal coronary balloon angioplasty; single vessel) has an MUE of 1. Code +92984 (... each additional vessel [List separately in addition to code for primary procedure]) has an MUE of 2. So to report the fourth vessel PTCA, you would need to add your payer's preferred modifier and include proof of the patient's need for PTCA in all four vessels.