Where do we go from here? Beyond the MagnaSafe trial: A focus beyond a 'safety-first' notion. An MRI study in 500 consecutive patients

Abstract

Background: In patients with conventional pacemakers or ICD's, MRI is infrequently performed due to safety concerns. Recent reports have allayed many of these concerns. However, the additive clinical value of scanning patients with cardiac implants has not been established.

Objective: Assessing the additive value of thoracic and non-thoracic MRI in patients with implantable cardiac devices.

Methods and results: Prospective data were analyzed in 500 patients with implanted cardiac devices that underwent MRI over a 12 year period at a single institution (Allegheny General Hospital, Pittsburgh, PA). A set of three questions were answered following scan interpretation by both the MRI technologist and interpreting MRI physician(s): 1) Did the primary diagnosis change? 2) Did 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 guiding therapy. Scans encountered were neurological/neurosurgical 354 (70.8%), cardiac 98 (19.6%) and orthopedic 48 (9.6%) in nature. In 431 (86%) MRI added additional information to the primary diagnosis and in 277 (55.4%) MRI changed the primary diagnosis. In 304 (60.8%) cases management changed, 265 (53%) due to a change in diagnosis and in 39 (7.8%) due to providing additional information. No safety issues were encountered and no adverse effects of MRI scan were noted.

Conclusions: MRI in patients with implanted cardiac devices was of additive value to diagnosis and management thereby informing risk-benefit considerations.

Condensed abstract: 500 patients with implanted cardiac devices who underwent a MRI examination over a 12 year period were followed prospectively. Imaging primarily focus on three anatomical regions (neurological/neurosurgical, cardiac and orthopedic) providing added information to the primary diagnosis in 431 (86%) cases and changing the primary diagnosis in 277 (55.4%) cases. In 304 (60.8%) cases management changed with 265 (53%) being due to a change of diagnosis and in 39 (7.8%) due to providing additional information. No safety issues were encountered using a defined protocol.

Conclusions: MR imaging retains its diagnostic yield in patients with implanted devices.

Keywords: ICD; Implantable devices; Magnetic resonance imaging; Pacemakers.