Quantitative analysis of the isolation area after larger-size laser balloon ablation

Background The visually guided laser balloon ablation is a balloon-based catheter ablation technology used for atrial fibrillation (AF) ablation in recent years. This balloon catheter consists of a compliant balloon that has the capability of real-time endoscopic visualization of the targeted pulmonary vein (PV). The sizeable balloon is usually inflated to obtain optimal PV occlusion. The isolation area after laser balloon (LB) ablation was reported to be smaller than that after cryoballoon ablation. However, when LB is inflated with its maximum pressure, it can visualize wide-area PV antrum. Thereby, we suspected that larger-size LB can create wider isolation area. Purpose The aim of this study is to quantitatively evaluate the isolation area after LB ablation at the size larger than appropriate size for ablation in the pulmonary vein carina region. Methods We assessed 66 patients with AF who underwent LB ablation at the larger inflation size in our hospital during the period from July 2018 to July 2019. After LB ablation, we created voltage maps with a circular mapping catheter and calculated isolation areas with CARTO system. Results Figure shows a larger LB with its maximum pressure. PV antrum isolation was extended to the posterior wall in all patients. The left- and right-sided pulmonary vein antrum isolation area were 15.1±3.9 and 19.4±4.3 cm2, respectively. Conclusion LB at the larger inflation size with its maximum pressure can isolate wider-area circumferential PV antrum than previously reported. This method may be a new way of pulmonary vein antrum isolation. Left atrial voltage mapping after PVI. Funding Acknowledgement Type of funding source: None

LEFT ATRIAL MECHANICAL FUNCTION AND ITS DISORDERS AFTER PULMONARY VEIN ANTRUM ISOLATION

The article presents new insights into the left atrial mechanical function, its main components and remodeling mechanisms after pulmonary vein antrum isolation. Left atrium is a cardiac chamber that transports blood. Being a complex «organ» both in anatomical and functional terms, it responds to hemodynamic derangements, the impact of humoral and vegetative factors. Structural, mechanical and electrical remodeling of the left atrium play a key role in the arrhythmogenesis of atrial fibrillation, as well as in the mechanism of arrhythmia maintenance. Left atrial mechanical dysfunction following catheter ablation of atrial fibrillation significantly affects intracardiac hemodynamics, worsens patients' well-being, and increases the risk of thromboembolic complications both in the immediate and long-term postoperative period.

Percutaneous Treatment of Non-paroxysmal Atrial Fibrillation: A Paradigm Shift from Pulmonary Vein to Non-pulmonary Vein Trigger Ablation?

Pulmonary vein antrum isolation is the most effective rhythm control strategy in patients with paroxysmal AF. However, catheter ablation of non-paroxysmal AF has a lower success rate, even when persistent isolation of pulmonary veins (PVs) is achieved. As a result of arrhythmia-related electophysiological and structural changes in the atria, sites other than the PVs can harbour triggers. These non-PV triggers contribute to AF relapse. In this article, we summarise the rationale and current evidence supporting the arrhythmogenic role of non-PV triggers and our ablation approach to patients with non-paroxysmal AF.