Letter from the Editor in Chief

DOI: 10.19102/icrm.2015.061001

MOUSSA MANSOUR, MD, FHRS, FACC

Editor-in-Chief

Dear Readers,

This issue of the Journal contains two excellent articles which relate to rotor mapping and ablation, a topic that has received significant attention lately. The article by Tomassoni et al. describes a single center experience with the RhythmView™ system (Topera Inc., Menlo Park, CA). They reported that rotor ablation results in a promising long-term success rate in a patient population with previous ablation when performed in addition to pulmonary vein isolation (PVI). The second article by Kurian et al. describes custom-made software that uses data from stationary and roving multipolar catheters to create panoramic three-dimensional maps of atrial fibrillation (AF) enabling direct visualization of rotors.

The strong interest in rotor mapping and ablation over the recent years probably stems from the non-satisfactory success rate with ablation of persistent AF. Circumferential PVI is one of the primary treatments for symptomatic drug-refractory paroxysmal AF. However, the clinical success rate observed with this approach alone has not been realized in patients with persistent AF. As a result, investigators have attempted different alternative approaches for ablation of persistent AF, one of which is rotor mapping and ablation.

The concept of one or few rotors driving AF is intriguing and is based on robust pre-clinical studies of AF mapping in animal and experimental models. However, the data from clinical trials have not been as conclusive as the animal studies. The information on the number of rotors and their stability has been conflicting. Some studies have shown that rotors last in excess of 30 minutes, while others revealed that the reentrant electrical activity is limited to one or two rotations. Moreover, the result of rotor ablation has also been significantly different among these studies, ranging from termination of AF with few minutes of radiofrequency ablation at one extreme, to no effect on the cardiac rhythm at the other end of the spectrum. These inconsistent findings have resulted in uncertainty and hesitation in the field of rotor mapping and ablation.

The success rate achieved with PVI in patients with paroxysmal AF using new technology such as force sensing catheters and second generation cryo-balloon, combined with adenosine infusion and high-frequency jet ventilation, is currently approaching that of ablation for common supraventricular tachycardia. As a result rotor mapping and ablation in this patient population will have negligible effect. What is more needed is a large well designed randomized multicenter clinical study comparing PVI alone, to PVI in addition to rotor ablation in patients with persistent AF. Such a study may help clarify the uncertainty surrounding rotor ablation and ablation.

Best regards and I hope you enjoy reading this issue of the Journal.

Regards,

Editor-in-Chief

Moussa Mansour, MD, FHRS, FACC
Editor-in-Chief
The Journal of Innovations in Cardiac Rhythm Management
MMansour@InnovationsInCRM.com
Director, Cardiac Electrophysiology Laboratory
Director, Atrial Fibrillation Program
Massachusetts General Hospital
Boston, MA