February 28, 2005

ACR Radiology Coding Source™ January-February 2005

Coronary CT Angiography

Early in the evolution of coronary CT angiography, when the work and practice expense were not clearly established, the American College of Radiology recommended that coronary CTA be coded as a conventional chest CT angiogram, using CPT® code 71275 (Computed tomographic angiography, chest, without contrast material(s), followed by contrast material(s) and further sections, including image post-processing). Since that time, it has become apparent that the CT techniques for high-quality coronary CTA are vastly different from the examinations described by 71275 with respect to field of view, slice thickness, gating requirements, reconstruction algorithms, and even scanner requirements. For this reason 71275 should not be used to describe dedicated CT and CTA of the heart and coronary vasculature. Instead, the ACR now recommends that the unlisted CPT code 76497 (Unlisted computed tomography procedure (eg, diagnostic, interventional)) be used to describe the CT evaluation of the coronary vasculature, as well as the other special cardiac CT and CTA examinations under development.

Coronary CTA is typically performed as a stand-alone examination dedicated to the evaluation of the coronary arteries, and it has the potential to supplant conventional catheter angiography for many patients. The CTA of the chest code, 71275, was valued to address imaging and angiographic reconstruction of the noncoronary thoracic vessels (eg, rule out pulmonary embolism and aortic dissection). It was not valued to address coronary artery evaluation. The typical acquisition and post-processing protocols used for pulmonary embolism or aortic dissection do not supply the information needed for exclusion of coronary artery occlusive disease. To obtain this additional information, acquisition and post-processing algorithms dedicated to evaluation of coronary vessels are used instead of those employed for a conventional CTA of the chest examination. That is why the ACR is now recommending that the unlisted code 76497 be used to describe coronary CTA. The use of the unlisted procedure code is used in the CPT® process to collect data on new procedures to determine the extent of use across the United States.

In certain emergency cases of acute chest pain, CTA is occasionally used to evaluate for the presence of pulmonary embolism, aortic dissection, and coronary artery stenosis. This application of CTA, commonly referred to as a "triple ruleout™ study," consists of a combination of two separate noninvasive examinations: CTA examination of the aorta and pulmonary vasculature, and CTA examination of the coronary vasculature. When a CTA study is performed to evaluate the aorta, pulmonary vasculature, and coronary vasculature, it is recommended that 71275 be reported to describe the conventional CTA (ie, evaluation of the aorta and pulmonary vessels), and that the unlisted procedure code 76497 be reported to describe the examination of the coronary circulation. CPT® codes 71275 and 76497 are not mutually exclusive and may be reported by the same physician for the same patient on the same date of service.

The ACR is working with the American College of Cardiology to create a new CPT® code to describe coronary CT angiography. The earliest a new code could be developed is 2007 for a Category I code or 2006 for a Category III code. Until a new code is created, the position of the ACR is that, unless a specific payer has advised otherwise (some private payers are requesting use of the temporary HCPCS code S8093), coronary CT angiography should be coded as an unlisted computed tomography procedure (76497).

For a detailed discussion of CTA and CT in conjunction with CTA, please reference the May/June 2003 ACR Radiology Coding Source™ feature article. For the coding of other specific thoracic vascular CT and MR applications, please reference this table.