Pacemakers and magnetic resonance imaging: no longer an absolute contraindication when scanned correctly

Until recently, cardiac pacemakers and implantable cardioverter defibrillators were considered an absolute contraindication for magnetic resonance imaging. Given the significant increase in implanting such devices, these contraindications will preclude MRI scanning in a large patient population. Several recent reports have addressed the safety and feasibility of MRI in the presence of cardiac implantable devices.

To summarize our experience with MRI scanning in the presence of pacemakers and implantable cardioverter defibrillators.

Eighteen patients (15 males and 3 females, median age 59) were scanned using a 1.5 T MRI scanner. A clinical discussion was held to verify the absolute medical necessity of the study before performing the scan. Scan supervision included device interrogation and programming beforehand, patient monitoring during, and device interrogation and reprogramming after the scan. Full resuscitation equipment was available outside the MRI suite.

Thirty-four scans were performed, and all but one were of diagnostic quality. Anatomic regions included the brain (N = 26), cervical spine (N = 2), lumbar spine (N = 1), cardiac (N = 2), abdomen (N = 1), abdomen and pelvis (N = 1) and pelvis (N = 1). None of the patients reported any side effects and no life-threatening events occurred during or following the scans. Five cases of device spontaneous reversion to backup mode were recorded (four in the same patient). Device replacement was not required in any patient.

In this small cohort of patients MRI scanning in the presence of cardiac implantable devices was safe. MRI in these patients is feasible although not recommended for routine scans. Scans should be considered on a case-to-case basis and performed in a dedicated specialized setup.