Abstract 14195: Diagnostic Value of MRI in Patients With Implanted Cardiac Devices: Does the Benefit Justify the Risk?

Abstract

Background: MRI is infrequently performed on patients with conventional pacemakers/ICD’s. Multiple recent studies and registries (MagnaSafe) have documented the safety of MRI in these patients, yet the diagnostic value of this approach has not been established remaining a critical issue to advance this field in an era of progressive MRI useage. Objective: 1) to examine a protocol to assess the diagnostic utility of thoracic and non-thoracic MRI in patients with implantable devices and 2) to determine if there is substantial benefit to the pt with regard to diagnosis and/or management. Methods: Over 8 years, 134 pts with PM/AICD’s underwent MRI (GE, 1.5T Milwaukee, WI) at a single institution. Specific criteria were followed for all pts to objectively define whether final diagnosis by MRI imaging enhanced patient care. A checklist of three questions was answered following scan interpretation by both the technologist and performing MRI physician(s):1) Did the primary diagnosis change? 2) Did the MRI provide additional information to the existing diagnosis? 3) Did patient management change? If ’Yes’ was answered to any of the above questions, it was considered that the MRI scan was of value to patient diagnosis and/or therapy. Results: All 134 pts underwent MRI/CMR without complications: avg scan time 24±9min including 42 pts with ICD’s, 5 pts with a retained lead and 87 non-MR conditional pacemakers. In 83% (n=112) MR added value to patient diagnosis and management. In 64% (n=86) MRI added additional valuable information to the primary diagnosis and in 19% (n=26) MRI was life-saving, changing the principal diagnosis and subsequent management of the pt. There were no deaths, arrhythmias or power-on-resets encountered and no adverse effects were noted in any pt. No post-procedure revisions or reimplantations of generator/lead were required. Conclusions: MR imaging in patients with implanted cardiac devices adds substantial value to patient diagnosis and management justifying the risk of the procedure. In this real-world patient population, we have shown that MR imaging retains its very high diagnostic yield. Risk-benefit ratios clearly justify the performance of MRI even in this higher risk population, that is, until such time as MR-conditional devices are universal.