Pranav Bhagirath

114 Chapter 6 Devices The availability of MR-compatible devices is currently extremely limited. The majority of the devices are used for investigative purposes and are yet to obtain regulatory approval. Instrumentation EP study A conventional EP study requires a recording and mapping system, stimulator and an RF generator. Currently there is no MRI-compatible equipment available commercially. As a result, every center has their customized solution. Several centers are investigating devices from Imricor Medical Systems (Burnsville, MN) and MRI Interventions (Irvine, CA). These companies are in the process of developing a range of MRI compatible devices with regulatory approval 24, 25, 31 . EAM An important component of the conventional EP studies is the EAM system that allow for catheter navigation inside realistic anatomical heart models. Recent studies have proposed modifications to create MRI compatible EAM systems 36 . The introduction of such an EAM system will offer the prospect of a fully integrated approach, suitable for MRI-based navigation, deployment of specific, targeted ablation, and immediate evaluation of therapy. Catheters Essential components in performing EP procedures are the diagnostic and ablation catheters. Both passive and active catheters have been used for investigational purposes in animals. However, due to safety concerns (heating) all human trials have been conducted using passive tracking only ( table 1 ). Although active tracking is not a pre- requisite for iCMR guided EP, active catheters can be used for device guided navigation. This feature eliminates operator interaction for manual scanning plane adjustment. In addition, the improved visibility of active catheters may contribute towards reducing procedural duration. Guidewire Performing interventional EP procedures may require the use of guidewires to facilitate the insertion of multiple sheaths and guidance of some catheters required during ablation. Passive guidewires have been successfully applied during cardiac interventions and are being investigated in larger trials 37 . The major limitation of using active guidewires is the potential of RF coupling due to the substantial length of these devices. This restriction has recently been addressed by the development of an