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Beyond Pulmonary Vein Isolation: the Role of Additional Sites in Catheter Ablation of Atrial Fibrillation

  • Invasive Electrophysiology and Pacing (EK Heist, Section Editor)
  • Published:
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Abstract

Purpose of Review

Pulmonary vein (PV) isolation is the cornerstone of atrial fibrillation (AF) ablation. However, the long-term procedural outcome remains suboptimal and there is a frequent need for repeat ablation procedure, especially in patients with non-paroxysmal AF. The review article summarizes the rationales, recent evidences, and strategies of ablation of extra-PV sites and its clinical outcomes.

Recent Findings

It is a consensus that durable PV isolations are a definite therapy in patients with paroxysmal AF. In non-paroxysmal AF, many laboratories still believe that adequate substrate ablation outside PVs is definitely required. Empirical linear ablation is not recommended because of difficulty in achieving complete linear block, unless macro-reentry atrial tachycardia developed during procedure. Most of laboratories applied complex fractionated atrial electrogram (CFAE) ablation after PV isolation in non-paroxysmal AF, but the efficacy is limited in the long-term follow-up studies. A combined approach using CFAE, non-linear similarity, and phase mapping strategy to identify rotors or focal sources for substrate modification increases the ablation outcome, when compared to CFAE ablation alone. Provocative test with mapping of non-PV triggers is also recommended in all patients to improve long-term ablation success.

Summary

Ablation beyond PV isolation is important, especially in non-paroxysmal AF patients, to modify the diseased atrial substrate and eliminate the non-PV triggers, which in turn improve the ablation outcome.

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Authors and Affiliations

  1. Division of Cardiology, Department of Medicine, Taipei Veterans General Hospital; Institute of Clinical Medicine, and Cardiovascular Research Institute, National Yang-Ming University, 201, Sec. 2, Shih-Pai Road, Taipei, Taiwan

    Li-Wei Lo, Yenn-Jiang Lin, Shih-Lin Chang, Yu-Feng Hu, Fa-Po Chung & Shih-Ann Chen

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Correspondence to Shih-Ann Chen.

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Conflict of Interest

Li-Wei Lo, Yenn-Jiang Lin, Shih-Lin Chang, Yu-Feng Hu, Fa-Po Chung, and Shih-Ann Chen declare that they have no conflict of interest.

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.

Funding

The present work was supported by the Taipei Veterans General Hospital (V102B-002, V102E7-003, V103C-042, V103C-126, V103E7-002, VGHUST103-G1-3-1, V104C-131, V104E7-003, VA105C-60), Ministry of Science and Technology (NSC 101-2911-I-008-001, NSC 102-2325-B-010-005, MOST 103-2314-B-075-062-MY3, MOST 104-2314-B-075-065-MY2), and Research Foundation of Cardiovascular Medicine (RFCM 100-02-011, 101-01-001, 104-01-009-01).

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Lo, LW., Lin, YJ., Chang, SL. et al. Beyond Pulmonary Vein Isolation: the Role of Additional Sites in Catheter Ablation of Atrial Fibrillation. Curr Cardiol Rep 19, 86 (2017). https://doi.org/10.1007/s11886-017-0884-4

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