Advances in Real-Time MRI–Guided Electrophysiology

Abstract

Purpose of ReviewTheoretical benefits of real-time MRI guidance over conventional electrophysiology include contemporaneous 3D substrate assessment and accurate intra-procedural guidance and evaluation of ablation lesions. We review the unique challenges inherent to MRI-guided electrophysiology and how to translate the potential benefits in the treatment of cardiac arrhythmias.Recent FindingsOver the last 5 years, there has been substantial progress, initially in animal models and more recently in clinical studies, to establish methods and develop workflows within the MR environment that resemble those of conventional electrophysiology laboratories. Real-time MRI-guided systems have been used to perform electroanatomic mapping and ablation in patients with atrial flutter, and there is interest in developing the technology to tackle more complex arrhythmias including atrial fibrillation and ventricular tachycardia.SummaryMainstream adoption of real-time MRI-guided electrophysiology will require demonstration of clinical benefit and will be aided by increased availability of devices suitable for use in the MRI environment.

Acute enhancement of necrotic radio‐frequency ablation lesions in left atrium and pulmonary vein ostia in swine model with non‐contrast‐enhanced T1‐weighted MRI

“…In the conventional EP setting, the proposed non-CE imaging technique for acute identification of necrotic RF ablation lesions may be useful to assess the completeness of treatment before discharging the patient. In future settings where ablation treatment could be carried out in the MR scanner, [58][59][60] non-CE imaging assessment of lesions may be carried out multiple times, to direct additional treatment to areas of incomplete ablation and potentially reduce arrhythmia recurrence.…”

Updating the Risk Stratification for Sudden Cardiac Death in Cardiomyopathies: The Evolving Role of Cardiac Magnetic Resonance Imaging. An Approach for the Electrophysiologist

“…The first necessary step in this algorithm is to incorporate CMR into 3D-EAM in order to transfer anatomical data from one software environment to the other. Potential causes of a mismatch include different rhythms during different image acquisition timings, as well as different loading conditions, leading to slight geometric alterations in chamber geometry [117], as it has been shown in several studies [55,118,119]. Regarding the association between scar features and measured voltages, a correlation between both bipolar and unipolar values with scar nature (dense/border, transmurality) has been reported [118].…”

Advancements in Imaging for Atrial Fibrillation Ablation: Is There a Potential to Improve Procedural Outcomes?

“… 43 The major advantages of real-time cardiac MRI include providing real-time information on lesion formation and supporting a reduction in fluoroscopy; however, the technology of real-time cardiac MRI in the EP laboratory is still in its infancy. Several centers have reported conducting simple atrial flutter ablations under cardiac MRI guidance 44 but significant improvements in workflow and noise and image artifact control with suitable electrogram recordings, mapping, and ablation in the strong electromagnetic field associated with this imaging modality have to be resolved before its wide acceptance can proceed.…”