Rotors as Drivers of Atrial Fibrillation and Targets for Ablation
Atrial fibrillation (AF) is the most common arrhythmia targeted by catheter ablation. Despite significant advances in our understanding of AF, ablation outcomes remain suboptimal, and this is due in large part to an incomplete understanding of the underlying sustaining mechanisms of AF. Recent developments of patient-tailored and physiology-based computational mapping systems have identified localized electrical spiral waves, or rotors, and focal sources as mechanisms that may represent novel targets for therapy. This report provides an overview of Focal Impulse and Rotor Modulation (FIRM) mapping, which reveals that human AF is often not actually driven by disorganized activity but instead that disorganization is secondary to organized rotors or focal sources. Targeted ablation of such sources alone can eliminate AF and, when added to pulmonary vein isolation, improves long-term outcome compared with conventional ablation alone. Translating mechanistic insights from such patient-tailored mapping is likely to be crucial in achieving the next major advances in personalized medicine for AF.
KeywordsAtrial fibrillation Ablation Focal sources Rotors Substrate Trigger
This work was supported by grants to S. Narayan from the NIH (HL70529, HL83359, HL103800) and the Doris Duke Charitable Foundation.
Compliance with Ethics Guidelines
Conflict of Interest
Amir A. Schricker and Gautam G. Lalani declare that they have no conflict of interest.
David E. Krummen has received fellowship support from Biosense-Webster, Biotronik, Medtronic, and St. Jude Medical and consultant’s fees from Boston Scientific. Sanjiv Narayan is co-author of intellectual property owned by the University of California Regents and licensed to Topera Inc. Topera does not sponsor any research, including that presented here. S. Narayan holds equity in Topera; has received honoraria and fellowship support from Biotronik, Medtronic, and St. Jude Medical; has received consultant’s fees from the American College of Cardiology and Elsevier; and has received royalties from UpToDate.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
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