Novel ICD System Deemed Safe for Full-Body MRI
(HealthDay News) — A novel implantable cardioverter-defibrillator (ICD) system specifically designed for full-body magnetic resonance imaging (MRI) is safe, according to a study published online May 14 in the Journal of the American College of Cardiology. The research was published to coincide with the annual meeting of the Heart Rhythm Society, held from May 13 to 16 in Boston.
Michael R. Gold, M.D., Ph.D., from the Medical University of South Carolina in Charleston, and colleagues conducted a multicenter, randomized trial of a novel ICD system. Participants were enrolled and underwent MRI with 1.5 Tesla of the chest, cervical, and head regions (175 individuals) or to a one-hour waiting period without MRI (88 individuals). The primary safety objective was >90 percent freedom from MRI-related events composite end point within 30 days after MRI. Ventricular pacing capture threshold (VPCT) and ventricular sensing amplitude were the primary efficacy end points.
The researchers found that the safety end point was met (100 percent freedom from the composite end point; P < 0.0001). Both efficacy end points were met; there was a minimal difference in the proportion of patients who demonstrated a ≤0.5 V increase in VPCT (100 and 98.8 percent in MRI and control groups, respectively) or a ≥50 percent reduction in R-wave amplitude (99.3 and 98.8 percent, respectively). After MRI there were 34 ventricular tachycardia/ventricular fibrillation events in 24 subjects, with no impact on sensing, detection, or treatment.
"These data supports that the system is safe and the MRI scan does not adversely affect electrical performance or efficacy," the authors write.
Several authors disclosed financial ties to medical device companies, including Medtronic, which funded the Evera MRI Study.