The controversy over advanced cardiovascular imaging: relative roles of radiologists, cardiologists, and other physicians in CT and MRI of the cardiovascular system.

PURPOSE: There is considerable conflict between radiologists and cardiologists over who has the experience and knowledge to perform computed tomography (CT) and magnetic resonance imaging (MRI) of the cardiovascular (CV) system. The purpose of this study was to determine the relative roles of the different specialties in these procedures.

METHOD AND MATERIALS: The nationwide 2003 Medicare Physician Supplier Procedure Summary Master Files were used to study all 8 codes for CT angiography and all 12 codes for magnetic resonance angiography and MRI of the heart. The database provides information on the number of studies performed in each code and the specialties of the physician providers. All professional component and global claims were tabulated, but technical-component-only claims were excluded because that would have led to double counting studies.

RESULTS: In 2003, in the Medicare fee-for-service population, a total of 266,142 CV CT studies were performed. Radiologists performed 257,581 (96.8%), and cardiologists performed 1,246 (0.5%). Primary care physicians (PCPs) and radiation oncologists each performed more of these studies than cardiologists: 1,879 and 1,389, respectively. Independent diagnostic testing facilities (IDTFs) and multispecialty groups together performed 2,398 (0.9%); although Medicare lists each of them as a medical "specialty," the actual specialty of a provider cannot be determined. A total of 110,743 CV MRI studies were performed. Radiologists did 100,788 (91.0%), and cardiologists did 3,257 (2.9%). In addition, IDTFs and multispecialty groups together performed 4,644, PCPs 753, and radiation oncologists 537.

CONCLUSION: Cardiologists had only minimal roles in CV CT and MRI in 2003. Their procedure volume was so small that it raises a question as to whether they could be gaining meaningful experience or providing meaningful training to fellows. Radiologists strongly dominated in the use of these modalities for imaging CV structures.