Prophylactic catheter ablation for ventricular tachycardia reduces morbidity and mortality in patients with implantable cardioverter–defibrillator devices

Abstract Background Although the use of implantable cardioverter–defibrillator/cardiac resynchronization therapy device with a defibrillator (ICD/CRT‐D) is the principal therapy for patients with life‐threatening ventricular tachyarrhythmias/ventricular fibrillation (VT/VF), prophylactic VT ablation may reduce arrhythmic episodes and mortality in patients with an ICD/CRT‐D. In this retrospective study, the prognoses among patient groups with different results of attempted VT ablation were compared. Methods The study population consisted of 151 consecutive patients with an ICD/CRT‐D and structural heart disease. The mean age was 64±9 years, and 63 of the 151 patients were women. Of the 151 patients, 117 cases underwent catheter ablation procedure for elimination of monomorphic VT. The 151 patients were divided into 3 groups based on the results of the ablation or whether ablation was attempted, i.e., success, failure, and not‐attempted groups (n=87, 30, and 34, respectively). The event rate of VT/VF and total mortality were compared among the 3 groups. Results During a follow‐up period of 31±22 months, VT/VF episodes and death occurred in 45 (30%) and 16 (11%) patients, respectively. When comparing the 3 groups, the rates of VT/VF episodes and death were significantly lower in the success group than in the failure and not‐attempted groups (16.1%, 46.7%, 50.0%, p=0.0001 and 6.9%, 20.0%, 11.8%, p=0.0213, respectively). Conclusion In patients with an ICD/CRT‐D implant for VT/VF, prophylactic ablation of monomorphic VT may reduce morbidity and mortality

Morphological Properties of Atrial Fibrillation Waves in Patients with Left Ventricular Dysfunction—Spectral Analysis of Atrial Fibrillation Waves in Dilated Cardiomyopathy—

AbstractIntroduction: Although the atrial fibrillation cycle length (FCL) is considered to shorten in persistent atrial fibrillation (AF) as a result of electrical remodeling, whether a long-term change remains in FCL in patients with left ventricular (LV) dysfunction is uncertain. Morphological properties of AF waves were analyzed in patients with dilated cardiomyopathy (DCM). Methods and Results: The study population consisted of 43 patients with persistent AF, and they were divided into a DCM group (n = 14) and a control group (n = 29). Fibrillation waves from surface ECG lead V1 were purified by subtracting the QRS-T complex template. Power spectral analysis was performed by Fast Fourier Transformation, and the mean FCL was determined by the peak power frequency in 20 epochs at each recording. The LV ejection fraction was lower in the DCM group (50 ± 18%) than the control (63 ± 8%, p = 0.001). The mean FCL was shorter in the DCM group (132 ± 14 ms) than the control (151 ± 23 ms, p = 0.007) and there was a significant correlation between the FCL and LV dimensions (p = 0.03). Conclusion: In patients with persistent AF and LV dysfunction, FCL was shorter in comparison with the control, and seemed to be influenced by LV dimensions

Variation in heart rate range by 24‐h Holter monitoring predicts heart failure in patients with atrial fibrillation

Abstract Aims The analysis of heart rate (HR) changes, such as the HR variability or HR turbulence, has been reported as a marker of cardiovascular events during sinus rhythm; however, those relationships during atrial fibrillation (AF) remain controversial, and those parameters are not commonly used in AF patients. We sought to investigate the relationship between a simple index focused on the HR and heart failure (HF) events in patients with permanent AF. Methods and results We enrolled 198 patients with permanent AF and evaluated the HR range, defined as the maximum HR minus the minimum HR on 24‐h Holter electrocardiogram recordings. The patients were divided into two groups, i.e., the larger (n = 101) and smaller (n = 97) HR range (HRR) groups, determined by the median value. The HF events were defined as hospitalizations for HF or urgent hospital visits due to exacerbations of one's HF status. The observation period of this study was set at 5 years from registration. The median age was 73 (68–77) years, and 29% were female. The median HRR was 84 (63–118) beats per minutes (bpm). During the observational period of 1825 days (median), HF events occurred in 37 (0.047 per patient‐year) patients. In a log‐rank test, the larger HRR group had more frequent HF events than the smaller HRR group (P = 0.0078). In the adjusted Cox proportional hazards model using the significantly different factors from the univariate analysis (Model 1) and factors and medications associated with HF (Model 2), the larger HRR group had a higher prevalence of HF events than the smaller HRR group for both models [Model 1, adjusted hazard ratio = 3.21, 95% confidence interval (CI) 1.593–6.708, P = 0.0009; Model 2, adjusted hazard ratio = 3.12, 95% CI 1.522–6.685, P = 0.002]. When analysed using the time‐dependent Cox proportional hazards model, the HRR was associated with HF with a statistically significant difference in both the univariate and multivariate analyses [hazard ratio = 1.01, 95% CI 1.006–1.020, P = 0.0002; Model 1, adjusted hazard ratio = 1.02, 95% CI 1.011–1.027, P < 0.0001; Model 2, adjusted hazard ratio = 1.01, 95% CI 1.008–1.021, P = 0.0003). There was no significant difference in the chronotropic medications between the two groups. Conclusions In patients with permanent AF, a larger HRR was associated with HF events

Atrial late potentials are associated with atrial fibrillation recurrence after catheter ablation

Abstract Background Previous studies have identified noninvasive methods for predicting atrial fibrillation (AF) recurrence after catheter ablation (CA). We assessed the association between AF recurrence and atrial late potentials (ALPs), which were measured using P‐wave signal‐averaged electrocardiography (P‐SAECG). Methods Consecutive patients with paroxysmal AF who underwent their first CA at our institution between August 2015 and August 2019 were enrolled. P‐SAECG was performed before CA. Two ALP parameters were evaluated: the root‐mean‐square voltage during the terminal 20 ms (RMS20) and the P‐wave duration (PWD). Positive ALPs were defined as an RMS20 115 ms. Patients were allocated to either the recurrence or nonrecurrence group based on the presence of AF recurrence at the 1‐year follow‐up post‐CA. Results Of the 190 patients (age: 65 ± 11 years, 37% women) enrolled in this study, 21 (11%) had AF recurrence. The positive ALP rate was significantly higher in the recurrence group than in the nonrecurrence group (86% vs. 64%, p = .04), despite the absence of differences in other baseline characteristics between the two groups. In the multivariate analysis, positive ALP was an independent predictor of AF recurrence (odds ratio: 3.83, 95% confidence interval: 1.05–14.1, p = .04). Conclusions Positive ALP on pre‐CA P‐SAECG is associated with AF recurrence after CA