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Introduction: Posterior wall isolation (PWI) combined with pulmonary vein isolation (PVI) has proven effective for persistent atrial fibrillation (AF). However, when performing PWI, creating transmural lesions with subendocardial ablation is sometimes difficult. Endocardial unipolar voltage amplitude had a higher sensitivity than bipolar voltage mapping for identifying intramural viable myocardium in the atria. In this study, we aimed to retrospectively investigate the correlation between the residual potential in the posterior wall (PW) following PWI for persistent AF and atrial arrhythmia recurrence using endocardial unipolar voltage. Methods: This was a single‐center observational study. Patients who underwent PVI and PWI for persistent AF in the first procedure between March 2018 and December 2021 at the Tokyo Metropolitan Hiroo Hospital were included in this study. The patients were divided into two groups based on the presence of residual unipolar PW potentials after PWI with a cutoff of 1.08 mV and the recurrence of atrial arrhythmias was compared. Results: In total, 109 patients were included in the analysis. Forty‐three patients had residual unipolar potentials after PWI and 66 patients had no residual unipolar potentials. The atrial arrhythmia recurrence rate was significantly higher in the group with residual unipolar potential (41.8% vs. 17.9%, p = 0.003). The residual unipolar potential was an independent predictor of recurrence (odds ratio: 4.53; confidence interval: 1.67–12.3, p = 0.003). Conclusion: Residual unipolar potential after PWI for persistent AF is associated with recurrent atrial arrhythmias. [ABSTRACT FROM AUTHOR]

Introduction: In patients with coronary artery disease, a high coronary artery calcium score (CACS) correlates with atrial fibrillation (AF); however, the association between left atrial (LA) remodeling progression and coronary arteriosclerosis is unclear. This study aimed to evaluate the relationship between LA remodeling progression and the CACS. Methods: This retrospective study enrolled 148 patients with AF (paroxysmal AF, n = 94) who underwent catheter ablation. Voltage mapping for the left atrium and coronary computed tomography for CACS calculations were performed. The ratio of the LA low‐voltage area (LA‐LVA), defined by values less than 0.5 mV divided by the total LA surface without pulmonary veins, was calculated. Patients with LA‐LVA (<0.5 mV) >5% and ≤5% were classified as the LVA (n = 30) and non‐LVA (n = 118) groups, respectively. Patient characteristics and CACS values were compared between the two groups. Results: LA volume, age, CHA2DS2VASc score, and percentage of female patients were significantly higher, and the estimated glomerular filtration rate was lower in the LVA group than in the non‐LVA group. The CACS was significantly higher in the LVA group (248.4 vs. 13.2; p =.001). Multivariate analysis identified the LA volume index and CACS as independent predictors of LA‐LVA (<0.5 mV) greater than 5%. The areas under the receiver operating characteristic curves for predicting LA‐LVA (<0.5 mV) greater than 5% with CACS were 0.695 in the entire population, 0.782 in men, and 0.587 in women. Conclusion: Progression of LA remodeling and coronary artery calcification may occur in parallel. A high CACS may indicate advanced LA remodeling, especially in men. [ABSTRACT FROM AUTHOR]

Introduction: It is important to consider recurrent arrhythmia after catheter ablation for persistent atrial fibrillation (AF) for planning an ablation strategy. However, the studies are limited to pulmonary vein isolation (PVI) plus posterior wall isolation (PWI), which were reported to improve procedural outcomes. The objective of this study is to evaluate the effect of PWI on recurrent arrhythmia. Methods: This is an observational study on patients with persistent AF comparing PVI plus PWI and PVI only strategies. In PVI plus PWI group, linear ablation of the left atrium roofline and bottom line were performed to achieve PWI after PVI. Some patients with AF recurrence underwent the second procedure. The presence of recurrent arrhythmia and results of the second procedures were evaluated. Results: A total of 181 patients (mean age, 66.9 ± 10.2 years; male, 76.8%) were included. PVI plus PWI group and PVI only group consisted of 90 and 91 patients, respectively. AF recurrence was observed in 28 of 90 (31.1%) patients with PVI plus PWI and in 43 of 91 (47.3%) with PVI only, and log‐rank test did not show any significant difference (p =.35). The occurrence of recurrent persistent AF was significantly lower in PVI plus PWI group than in PVI only group (5/90; 5.6% vs. 18/91; 20.9%, p =.002). There was no significant difference between the two groups in recurrent paroxysmal AF and atrial tachycardia (AT). Conclusion: PWI, in addition to PVI, for persistent AF was significantly related to fewer episodes of recurrent persistent AF, and it did not increase recurrent AT. [ABSTRACT FROM AUTHOR]

Abstract: Background: During epicardial mapping, determination of appropriate ablation sites in low voltage areas (LVA) is challenging because of large epicardial areas covered by adipose tissue. Objective: To evaluate the impedance difference between epicardial fat and the epicardial LVA using multiple detector computed tomography (MDCT). Methods: We enrolled patients who underwent ventricular tachycardia (VT) ablation via the epicardial approach after endocardial ablation failure. After the procedure, MDCT‐derived images of epicardial fat were loaded to the mapping system. Then, all points acquired during sinus rhythm were retrospectively superimposed and analyzed. Results: This study included data from 7 patients (62.5 ± 3.9 years old) who underwent eight epicardial VT ablation procedures. After the procedure, MDCT‐derived images of epicardial fat were registered in eight procedures. Retrospective analysis of 1,595 mapping and 236 ablation points was performed. Of the 1,595 mapping points on the merged electroanatomical and epicardial fat maps, normal voltage area (NVA) and low voltage area (LVA) without fat had lower impedance than those with fat (NVA without fat 182 ± 46 Ω vs. NVA with fat 321 ± 164.0 Ω, P  =  0.001, LVA without fat 164 ± 69 Ω vs. LVA with fat 248 ± 89 Ω, P  =  0.002). Of the 236 ablation points, initial impedance before ablation was higher on epicardial fat than on epicardial LVA without fat (134 ± 16 Ω vs. 156 ± 28 Ω, P  =  0.01). Conclusions: Real time epicardial impedance evaluation may be useful to determine effective epicardial ablation sites and avoid adipose tissue. However, the number of patients in the present study is limited. Further investigation with a large number of patients is needed to confirm our result. [ABSTRACT FROM AUTHOR]

Scar-Related Left Atrial Anterior Wall Reentry. Introduction: Macroreentrant atrial tachycardia (MRAT) has been described most frequently in patients with prior cardiac surgery. Left atrial tachycardia and flutter are common in patients who undergo atrial fibrillation ablation; however, few reports describe left atrial MRAT involving the regions of spontaneous scarring. Here, we describe left atrial MRAT in patients without prior cardiac surgery or catheter ablation (CA) and discuss the clinical and electrophysiological characteristics of tachycardia and outcome of CA. Methods and Results: An electrophysiological study and CA were performed in 6 patients (3 men; age 76 ± 6 years) with MRAT originating from the left atrial anterior wall (LAAW). No patient had a history of cardiac surgery or CA in the left atrium. Spontaneous scars (areas with bipolar voltage ≤ 0.05 mV) were observed in all patients. The activation map showed a figure-eight circuit with loops around the mitral annulus (4 counterclockwise and 2 clockwise) and a low-voltage area with LAAW scarring. The mean tachycardia cycle length was 303 ± 49 milliseconds. The conduction velocity was significantly slower in the isthmus between the scar in the LAAW and the mitral annulus than in the lateral mitral annulus (0.17 ± 0.05 m/s vs 0.94 ± 0.35 m/s; P = 0.003). Successful ablation of the isthmus caused interruption of the tachycardia and rendered it noninducible in all patients. Conclusion: Spontaneous LAAW scarring is an unusual cause of MRAT, showing activation patterns with a figure-eight configuration. Radiofrequency CA is a feasible and effective treatment in such cases. (J Cardiovasc Electrophysiol, Vol. 24, pp. 404-412, April 2013) [ABSTRACT FROM AUTHOR]

Objectives: The present study was performed to investigate the clinical implications of an implantable cardioverter-defibrillator (ICD) in patients with vasospastic angina (VSA) resuscitated from lethal ventricular arrhythmia. Background: The prognosis of VSA is known to be good with medication; however, ventricular arrhythmia and cardiopulmonary arrest are rare but life-threatening complications of this disease. The ICD is a proven modality for patients with ventricular arrhythmia, but the clinical implications in this population remain to be elucidated. Methods: We conducted a retrospective, observational, multicenter study involving patients with an ICD due to documented ventricular arrhythmia and VSA diagnosed by acetylcholine provocation test. All patients were followed up for appropriate ICD therapy, sudden cardiac arrest, or death from all causes. Results: Twenty-three patients were included in the present study and completely followed up. All patients are still alive. During a follow-up of 2.9 years (median 2.1 years), 4 ventricular fibrillations and 1 episode of pulseless electrical activity occurred in 5 patients (21.7%). There were no statistically significant differences in patient characteristics between the recurrence and nonrecurrence groups, including medication, smoking status, and whether the patient was or was not free of symptoms after ICD implantation. Conclusions: Patients with VSA and lethal ventricular arrhythmia are a population at high risk for recurrence of cardiopulmonary arrest, and there is no reliable indicator for predicting recurrence of ventricular arrhythmia. Insertion of an ICD with medication for VSA is appropriate for this high-risk population. [Copyright &y& Elsevier]