A novel catheter ablation strategy for non-paroxysmal atrial fibrillation combining cryoballoon, radiofrequency, and Marshall-vein ethanol ablations.

BACKGROUNDS: Catheter ablation for non-paroxysmal atrial fibrillation (non-PAF) remains challenging and more effective strategy has been required to reduce postoperative arrhythmia recurrences. This study aims to investigate the efficacy and safety of a novel extensive ablation strategy for non-PAF, that is based on a combination of cryoballoon (CBA), radiofrequency (RFA), and Marshall-vein ethanol ablations (EA-VOM). METHODS: The study was a single-center, retrospective observational study. We enrolled 171 consecutive patients who underwent de-novo catheter ablation for non-PAF under conscious sedation with a novel extensive ablation strategy that included CBA for pulmonary vein isolation (PVI) and left atrial roof ablation (LARA), RFA for mitral isthmus (MI) ablation, superior vena cava isolation, and other linear ablations and EA-VOM. Recurrence of atrial arrhythmias over 1 year, procedure outcomes, and procedure-related complications were investigated. RESULTS: A total of 139 (81.3%) patients remained in sinus rhythm during 1-year follow-up. Of the 139 patients, 51 patients (29.8%) received antiarrhythmic drugs. The mean procedure time was 204 ± 45 min. PVI and LARA ablation by CBA and MI block by RFA and EA-VOM were completed in 171 (100%) and 166 (97.1%) patients, respectively. No serious procedure-related complications were observed except for one case of delayed pericardial effusion. CONCLUSION: Approximately 80% of the study patients were AF-free during 1-year follow-up period after a single procedure based on the novel extensive ablation strategy combining CBA, RFA, and EA-VOM. This strategy for non-PAF may be preferred in terms of maintenance of sinus rhythm, safety even in high-risk patients, and relatively short procedure time.

Peri-procedural anticoagulation in patients with end-stage kidney disease undergoing atrial fibrillation ablation: results from the multicentre end-stage kidney disease-atrial fibrillation ablation registry.

AIMS: The optimal anticoagulation regimen in patients with end-stage kidney disease (ESKD) undergoing atrial fibrillation (AF) catheter ablation is unknown. We sought to describe the real-world practice of peri-procedural anticoagulation management in patients with ESKD undergoing AF ablation. METHODS AND RESULTS: Patients with ESKD on haemodialysis undergoing catheter ablation for AF in 12 referral centres in Japan were included. The international normalized ratio (INR) before and 1 and 3 months after ablation was collected. Peri-procedural major haemorrhagic events as defined by the International Society on Thrombosis and Haemostasis, as well as thromboembolic events, were adjudicated. A total of 347 procedures in 307 patients (67 ±9 years, 40% female) were included. Overall, INR values were grossly subtherapeutic [1.58 (interquartile range: 1.20-2.00) before ablation, 1.54 (1.22-2.02) at 1 month, and 1.22 (1.01-1.71) at 3 months]. Thirty-five patients (10%) suffered major complications, the majority of which was major bleeding (19 patients; 5.4%), including 11 cardiac tamponade (3.2%). There were two peri-procedural deaths (0.6%), both related to bleeding events. A pre-procedural INR value of 2.0 or higher was the only independent predictor of major bleeding [odds ratio, 3.3 (1.2-8.7), P = 0.018]. No cerebral or systemic thromboembolism occurred. CONCLUSION: Despite most patients with ESKD undergoing AF ablation showing undertreatment with warfarin, major bleeding events are common while thromboembolic events are rare.

Five-Year Impacts of Antithrombotic Therapy Based on 10-Year Clinical Outcomes of Cypher™ Stent Implantation.

INTRODUCTION: Few researchers have investigated the optimal long-term antithrombotic therapy regimen, especially after first-generation drug-eluting stent (DES) use. This study aimed to evaluate the impact of mid-term antithrombotic therapy on long-term outcomes in patients treated with the first sirolimus-eluting coronary stent (Cypher™). METHODS: Between 2004 and 2009, 1021 patients underwent Cypher™ implantation at our institute; among them, 567 patients had available data on antithrombotic therapy at year 5. We assessed patients' antithrombotic therapy at year 5 post Cypher™ implantation and examined their association with adverse events from year 5 to year 10 post Cypher™ implantation. RESULTS: Patients with dual-antiplatelet therapy (DAPT) at year 5 had significantly lower risk of stent thrombosis (ST) than those with single-antiplatelet therapy (SAPT) (hazard ratio [HR] 0.24, p = 0.034). The HR of major bleeding in DAPT, compared to SAPT, was high, but the difference was not significant (HR 1.72, p = 0.26). Risk of major bleeding was significantly higher in patients on oral anticoagulants (OAC) than in those in other groups (OAC/SAPT; HR 5.31, p = 0.0048, OAC/DAPT; HR 3.08, p = 0.022), without significant reduction in the risk of cardiovascular events. CONCLUSIONS: The incidence of ST after Cypher™ implantation in patients with DAPT at year 5 was significantly lower than that in SAPT. However, the risk of bleeding was higher with DAPT than with SAPT. Moreover, the risk of major bleeding was significantly higher in patients on anticoagulant therapy than in other patients. New options for the use of antithrombotic drugs after percutaneous coronary intervention warrant further studies on the optimal antithrombotic therapy for first-generation DES.

Fragmented QRS on far-field intracardiac electrograms as a predictor of arrhythmic events.

BACKGROUND: Studies suggest that fragmented QRS (fQRS) can predict arrhythmic events in various cardiac diseases. However, the association between fQRS recordings on intracardiac electrogram (EGM) and ventricular arrhythmic events remains unknown. METHODS: We enrolled 51 patients (age, 62 ± 12 years; 40 men) with an implantable cardioverter-defibrillator (ICD) and structural heart disease and evaluated surface electrocardiogram (ECG) and EGM measurement of fQRS and the association between fQRS and arrhythmic events. RESULTS: fQRS was detected on surface ECG and ICD-EGM in 12 (23.5%) and 15 (29.4%) patients, respectively. fQRS was detected more frequently on ICD-EGM in patients with fQRS on surface ECG than in patients without fQRS (7/12 [58.3%] vs 8/39 patients [20.5%], P = .01). Appropriate ICD therapies were documented in 16 patients. Among these patients, fQRS was detected more frequently on surface ECG and ICD-EGM in patients with appropriate ICD therapies (8/16, 50.0%; P = .001 and 11/16, 68.9%; P < .001). Nonsustained ventricular tachycardia was significantly more frequent in patients with appropriate ICD therapies (15/16, 93.8%; P = .04). Multiple logistic regression analysis showed that fQRS on ICD-EGM was a predictor of arrhythmic events (P = .03). Kaplan-Meier survival analysis revealed that ICD therapies were significantly more frequent among patients with fQRS on both surface ECG and ICD-EGM than among those without fQRS (66.7% vs 6.6%, P < .001). CONCLUSION: The presence of fQRS on ICD-EGM can be a predictor of arrhythmic events in ICD patients. Surface ECG and ICD-EGM measurement may help predict ventricular arrhythmic events.

Left ventricular lead placement using inner guiding catheter alone in cardiac resynchronization therapy device implantation.

BACKGROUND: Subselection inner catheters (Inner-Cath) are used adjunctively with outer guiding catheters (Outer-Cath) during cardiac resynchronization therapy (CRT) device implantation. This study aims to investigate the feasibility and efficacy of left ventricular lead placement (LV-LP) guided by Inner-Cath alone. METHODS: A total of 74 patients undergoing de novo CRT implantation were investigated. LV-LP was initially guided by Inner-Cath in 42 patients (Inner-Cath group) and Outer-Cath in 32 patients (Outer-Cath group). In the Inner-Cath group, a 7Fr Inner-Cath was advanced to the coronary sinus through a 7 Fr sheath inserted in a subclavian vein. In the Outer-Cath group, 9Fr or 10Fr Outer-Caths were used. Success rate of LV-LP, additional use of inner or outer catheters and procedure-related complications were compared between groups. RESULTS: LV-LP was successful in all patients in the Inner-Cath group, while LV-LP had to be abandoned in two patients (6.3%) of the Outer-Cath group due to CS perforation caused by Outer-Cath manipulation. Procedure time was significantly shorter in the Inner-Cath group (148 vs. 168 min; p = .024). Deployment of both an inner and outer cath became necessary less frequently for the Inner-Cath group (4.8% vs. 56.3%; p < .001). Mechanical CS injuries due to guiding catheter manipulation were only observed in the Outer-Cath group (0% vs. 15.6%, p = .013). CONCLUSION: LV-LP guided by Inner-Cath alone was feasible in over 95% of the patients without severe complications. This methodology for LV-LP may be preferable in CRT candidates with severe LV dysfunction in terms of shorter procedure time, smaller guiding sheath, and less procedure-related complications.

Efficacy of catheter ablation of focal sources in persistent atrial fibrillation.

INTRODUCTION: Recent studies suggest that atrial fibrillation (AF) is maintained by electrical activity arising from focal sources. We sought to test whether catheter ablation that targets focal sources can improve on current ablation protocols for persistent AF. METHODS AND RESULTS: In patients with persistent AF whose AF did not terminate with pulmonary vein (PV) isolation, the left atrium was mapped with a 20-pole high-density mapping catheter using CARTO® 3 navigation. If a site demonstrated centrifugal activation over at least three consecutive cycles, it was deemed a focal source and ablated. If AF remained, defragmentation was performed until AF was terminated. Freedom from atrial tachyarrhythmia was compared between the study patients and propensity score matched historical controls who had undergone conventional stepwise ablation. Of the 68 study patients, 2.9 ± 1.9 focal sources were identified in 60 patients. Focal sources displayed transient centrifugal activation patterns for a median of six consecutive cycles. Total radiofrequency duration was shorter in the study group (62 ± 16 minutes vs. 75 ± 24 minutes, P = 0.0003). During a 1-year follow-up period, 39 (57%) and 26 (38%) patients were free from atrial tachyarrhythmias in the absence of antiarrhythmic drugs in the study and control groups, respectively (hazard ratio: 1.85, 95% confidence interval: 1.17-2.96, P = 0.009). Improvement of clinical outcome was mainly driven by a decrease in recurrence of atrial tachycardia in the study patients (22% vs. 40%, P = 0.047). CONCLUSION: The results of this study suggest that focal sources are appropriate ablation targets in addition to the PVs in persistent AF.

Mechanisms of Diuresis for Acute Decompensated Heart Failure by Tolvaptan.

Tolvaptan, a vasopressin type 2 receptor antagonist, does not affect kidney circulation or cause worsening of renal function (WRF) in patients with acute decompensated heart failure (ADHF). Bioelectrical impedance analysis (BIA) can be used to evaluate intravascular volume by calculating the ratio of extracellular water (ECW) to intracellular water (ICW). There have been no reports examining the mechanisms of tolvaptan-induced diuresis using BIA. We investigated whether tolvaptan decreases excess volume while maintaining intravascular volume in ADHF patients.Study patients included 29 ADHF patients (age 48-95, men 69%) diagnosed between April 2013 and May 2016 and who underwent BIA before and after treatment. Fifteen patients were treated with tolvaptan in addition to conventional diuresis therapy (tolvaptan group), and 14 patients were treated with conventional diuresis therapy only (control group). In the control group, the numerical value of serum creatinine (Cre) significantly increased from 0.89 ± 0.22 mg/ dL to 1.07 ± 0.29 mg/dL (P = 0.004), and the ECW/ICW significantly decreased from 0.696 ± 0.036 to 0.673 ± 0.032 (P = 0.004). These values were not significantly different from those obtained for the tolvaptan group. Furthermore, regression analysis showed a negative correlation between ΔCre and ΔECW/ICW, which are the differences between values before and after treatment (ΔCre = -0.002-5.668 × ΔECW/ICW, r2 = 0.306, P = 0.002).Our findings suggest that WRF is caused by a reduction in intravascular volume and that tolvaptan treatment can decrease the excess volume while maintaining intravascular volume.

Novel Mapping Technique for Localization of Focal and Reentrant Activation During Atrial Fibrillation.

INTRODUCTION: Identification of wavefront propagation pattern during AF remains challenging in ablation procedures. We sought to test a novel combination of a new mapping technology called Ripple Map and high-density mapping to distinguish focal and reentrant activation during atrial fibrillation (AF). METHODS AND RESULTS: Subjects were patients undergoing ablation for persistent AF. If AF remained after isolation of the pulmonary veins, the left atrium (LA) was mapped by a high-density mapping catheter for later analysis, after which ablation was continued using a conventional stepwise approach. After the procedure, electrograms from the high-density mapping catheter were analyzed using Ripple Map, which is a new feature in the CARTO®3, and type of activation on ≥3 consecutive AF cycles was determined. High-density mapping was performed on 569 sites in 45 patients (13 ± 3 sites per patient). AF wavefront propagation determined by Ripple Map was in good agreement with analysis of manual annotation of bipolar electrograms. Ripple Map's representation of wavefront activation pattern, which could include local as well as far-field activity, allowed us to identify focal activation in 64 (11%) sites and 1 (0.2%) reentrant activation site. Radiofrequency delivery in atrial regions with activation sites identified as focal by Ripple Map resulted in termination of AF more often than regions without focal activation (22% vs. 7%, P = 0.015). CONCLUSION: This study demonstrated that Ripple Map enabled quick identification of AF wavefront activation pattern, potentially being helpful for determining ablation targets in persistent AF.