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  • Acknowledgement br Introduction Pulmonary veins PVs have bee

    2019-04-26

    Acknowledgement
    Introduction Pulmonary veins (PVs) have been reported to be the major site of ectopic foci initiating paroxysmal atrial fibrillation (AF) [1]. Pulmonary vein isolation (PVI) is an established therapy eliminating those foci [2,3]. Non-PV ectopic foci from the superior vena cava (SVC) or coronary sinus have also been reported [4,5]. Thus, an SVC isolation (SVCI) is considered to improve the rhythm outcome in patients with those foci [6]. However, the following procedural complications have also been documented after and during an SVCI: sinus V5 Tag injury, right phrenic nerve injury, and SVC stenosis [7–9]. Therefore, the assessment of the arrhythmogenicity of the SVC would be necessary before the procedure. The relationship between PV arrhythmogenicity and its anatomy has been reported [10–12]. However, the relationship between the SVC arrhythmogenicity and its anatomy has not been well discussed [13,14]. We hypothesized that dilatation of the SVC could be associated with SVC arrhythmogenicity. To avoid overestimating arrhythmogenicity at the SVC, we sought to assess the arrhythmogenic response induced by a simple extra stimulus pacing (scan pacing) at the SVC as a surrogate index of the arrhythmogenicity. And then, we also analyzed the relationship between the arrhythmogenic response and the anatomical dilatation of the SVC assessed by computed tomography (CT) images.
    Material and methods
    Results
    Discussion
    Conclusion
    Conflict of interest
    Acknowledgments
    Introduction Catheter-based pulmonary vein isolation (PVI) has become a widely accepted means of treating symptomatic drug-refractory atrial fibrillation (AF) [1]. However, for terminating persistent AF (PerAF), extensive ablation, including ablation at sites of complex fractionated atrial electrograms (CFAEs) and high dominant-frequency (DF) and/or multiple linear ablations may also be necessary [2–5]. CFAEs and/or high DF sites have been shown to be effective targets for AF termination, which suggests the importance of these sites in the maintenance of AF [2,5–8]. CFAEs and high DF sites theoretically represent abnormal substrates; however, sinus rhythm (SR) voltage recorded at the CFAE sites has been shown to be normal [9]. It has also been shown that most CFAE and high DF sites identified during AF do not correspond with high DF sites or low voltage areas identified during SR [10]. In the present study, we compared left atrial (LA) CFAEs and high DF sites identified during AF and LA bipolar voltage recorded during AF and SR by comparing LA bipolar electrograms obtained from both high-density mobile-catheter mapping and fixed-position basket-catheter mapping.
    Material and methods
    Results
    Discussion
    Conclusions
    Conflict of Interest
    Introduction Atrial fibrillation (AF) is the most commonly sustained arrhythmia and has been treated for years by using conventional radiofrequency ablation in a point-by-point fashion [1,2]. However, due to emerging technology, several single-device techniques have been used as alternatives in the therapy of pulmonary vein isolation (PVI). Within the scope of single-device techniques, cryoballoon ablation (CBA) has played a prominent role; it is a well-established technique for the ablation of paroxysmal atrial fibrillation (PAF), but is less commonly used for the ablation of persistent atrial fibrillation (PersAF) [3–5]. The isolation of pulmonary veins (PVs) is effective as a form of treatment for both PAF and PersAF. The elimination of all pulmonary vein potentials (PVPs) is the main goal in overcoming the arrhythmia. Mapping catheters can rapidly and effectively identify the site of first activation of the exiting PVPs, thus guiding radiofrequency ablation for effective, clinically efficient, and safe AF ablation procedures. For mapping electrical conduction between the left atrium and PVs, the most common tool is a conventional spiral catheter. The distal end of the catheter is an open, circular loop (with a loop diameter range of 15–25mm) equipped with either 10 or 20 electrodes. Standard spiral catheters are mainly used in conventional point-by-point radiofrequency ablation procedures.