Cardiac MRI stress testing in the reduction of radiation exposure for patients undergoing ischemic evaluation

Background Cardiac diagnostic testing is responsible for a significant portion of non-therapeutic radiation exposure in the United States. The major source of cardiac-related radiation exposure is nuclear based myocardial perfusion imaging (MPI). Furthermore, a higher radio-isotope dose is necessary for MPI in obese patients, a growing segment of the population. As of January 1, 2014, the American Society of Nuclear Cardiology (ASNC) recommended that measures be taken to ensure a mean dose of ≤9.0 mSv per MPI study, a goal which has been difficult for many institutions to achieve. This study was designed to assess the role of cardiac MRI (CMR) stress imaging in reducing radiation exposure in a “real-world” setting, particularly the growing subset of obese patients.