Novel, Magnetically Guided Catheter for Endocardial Mapping and Radiofrequency Catheter Ablation

Abstract

Background-Ablation of complex arrhythmias would be greatly facilitated by more precise control of ablation catheters.A feasibility study was performed in animals to evaluate a novel magnetic guidance system (MGS) that generates a magnetic field to control the movement and position of a magnetic ablation catheter. Methods and Results-The MGS is composed of a digital biplanar fluoroscope within an array of superconducting electromagnets that surround the torso of the experimental animal and a computer control system that generates a composite magnetic field for directional catheter deflection. Magnetic catheter navigation was performed in dogs and pigs (20 to 30 kg). A 7F magnetic ablation catheter was used for intracardiac navigation and radiofrequency ablation. The performance of a standard 7F deflectable catheter was not affected by the MGS. The magnetic catheter was navigated successfully to 51 predefined targets throughout the heart in 6 animals. In 5 animals, the magnetic catheter, guided by a 3D computed tomogram, was successfully navigated to all pulmonary veins. Navigation accuracy was estimated as Ͻ1 mm displacement from the target. The magnetic catheter was used to ablate the atrioventricular node in 4 animals and to perform linear ablations across the endocardial surface underlying an epicardial multielectrode recording plaque in 4 animals. Conclusions-These results demonstrate that the MGS can navigate and stabilize an ablation catheter at endocardial targets. Linear or focal radiofrequency ablation with the magnetic catheter is not compromised by the magnetic field.

Initial Experience With Remote Catheter Ablation Using a Novel Magnetic Navigation System

“…6 The ablation catheter held a stable position even with changing cardiac rhythms (such as junctional beats) and complex atrial anatomy (giant coronary sinus ostium in a patient with persistent left superior caval vein). 7 The option of reapplication of a previously applied magnetic field vector allowed renavigation to a previously visited site and thereby shortened both mapping and fluoroscopy time.…”

“…Recently, a novel magnetic navigation system (MNS) was introduced that allows the use of a soft ablation catheter that can be guided and positioned precisely by magnetic fields to any desired site within the cardiac chambers in an animal model. 6 We report our initial experience using the MNS for completely remote-controlled catheter ablation in the right atrium in patients with documented AVNRT.…”

An in vivo comparison of radiofrequency cardiac lesions formed by standard and magnetically steered 4 mm tip catheters

“…7,[10][11][12][13][14][15][16] Comparison of standard vs. magnetic catheters Ablation lesions formed by magnetically steered catheters have similar characteristics to those from standard catheters. The only significant differences appear to be that the lesions from magnetically steered catheters are more round or oval rather than elongated, suggesting more constant catheter tissue contact.…”

The Amigo™ Remote Catheter System: From Concept to Bedside

“…9,10 This system requires the use of flexible catheters that incorporate a permanent magnet inside the tip, to allow for the manipulation of their movement through the adjustment of the magnetic field's orientation. [9][10][11] During use, the catheter is advanced and withdrawn using a motor-driven unit (Cardiodrive s ; Sterotaxis, Inc., St. Louis, MO, USA) and is maneuvered by the operator, who is in the control room, through a video workstation (Navigantt; Sterotaxis, Inc., St. Louis, MO, USA). 9,10 The Niobe s system (Sterotaxis, Inc., St. Louis, MO, USA) is exceptionally accurate in achieving catheter positioning and is unlikely to cause cardiac perforation 11 since it utilizes a soft catheter that is pulled towards the endocardium by an external magnetic field, rather than a mechanically driven rigid catheter.…”