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We report a case of a 44-year-old male who underwent an electrophysiological study for symptomatic supraventricular tachycardia (SVT) with wide QRS complex. The SVT was diagnosed as an antidromic atrioventricular reentrant tachycardia (AVRT) via antegrade conduction of left-sided accessory pathway (AP). However, the QRS morphology changed during the SVT, and then the SVT was terminated spontaneously. The mapping of AP was performed during sinus rhythm, and the radiofrequency application successfully eliminated the AP, which rendered tachycardias non-inducible. This was a rare case of antidromic AVRT during which the QRS morphology changed., (© 2024 Wiley Periodicals LLC.)

Aims: Catheter ablation (CA) of atrial fibrillation (AF) improves left ventricular ejection fraction (LVEF) in patients with heart failure with reduced ejection fraction (HFrEF). The impact of ST-segment depression before CA on LVEF recovery and clinical outcomes remains unknown. In the present study, we aimed to investigate the relationship between ST-segment depression during AF rhythm before CA and improvement in the LVEF and clinical outcomes in persistent atrial fibrillation (PerAF) patients with HFrEF., Methods and Results: The present study included 122 PerAF patients (male; 98 patients, 80%, mean age: 69 [56, 76] years) from the Osaka Rosai Atrial Fibrillation ablation (ORAF) registry who had LVEF < 50% and underwent an initial ablation. The patients who underwent percutaneous coronary intervention or coronary artery bypass grafting within the past 1 month were not included in the enrolled patients. We assigned the patients based on the presence of ST-segment depression before CA during AF rhythm and evaluated improvement in the LVEF (LVEF ≥ 15%) 1 year after CA and the relationship between ST-segment depression and heart failure (HF) hospitalization/major adverse cardiovascular events (MACE), which are defined as a composite of HF hospitalization, cardiovascular death, hospitalization due to coronary artery disease, ventricular arrhythmia requiring hospitalization and stroke. The percentage of patients with improvement in the LVEF 1 year after CA was significantly lower in the patients with ST-segment depression than those without (58.6% vs. 79.7%, P = 0.012). Multiple regression analysis showed ST-segment depression was independently and significantly associated with improvement in the LVEF 1 year after CA (HR: 0.35; 95% CI: 0.129-0.928, P = 0.035). Kaplan-Meier analysis showed that the patients with ST-segment depression significantly had higher risk of HF hospitalization and MACE than those without (log rank P = 0.022 and log rank P = 0.002, respectively). Multivariable Cox proportional hazards analysis showed that ST-segment depression was independently and significantly associated with a higher risk of MACE (HR: 2.82; 95% CI: 1.210-6.584, P = 0.016)., Conclusions: ST-segment depression before CA during AF rhythm was useful prognostic predictor of improvement in the LVEF and clinical outcomes including HF hospitalization and MACE in PerAF patients with HFrEF., (© 2024 The Author(s). ESC Heart Failure published by John Wiley & Sons Ltd on behalf of European Society of Cardiology.)

Background: Residual non-pulmonary vein (PV) foci are significantly associated with atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI). However, we previously reported among patients with non-PV foci induced only once, none experienced AF recurrence. Thus, we aimed to investigate the correlation between the residual induction number of non-PV foci and ablation outcome in paroxysmal AF patients., Methods and Results: We investigated 55 paroxysmal AF patients with residual non-PV foci after PVI and ablation of non-PV-foci. Study patients were classified into the residual one-time induction of non-PV foci (residual OTI-nPVF) group (n = 23) and residual repeatedly induced non-PV foci (residual RI-nPVF) group (n = 32). Furthermore, the residual RI-nPVF group was divided into the low inducibility group (n = 10) and high inducibility group (n = 22) according to the presence or absence of non-PV foci provoked by two sets of drug induction tests (non-PV foci inducibility). In addition, the latter was divided into the ablation group (n = 14) or observation group (n = 8). The 2-year AF recurrence-free rate in the residual RI-nPVF group was significantly lower compared to the residual OTI-nPVF group (53% vs. 90%, p = 0.018). There was no significant difference of the 2-year AF recurrence-free rates in the inducibility of non-PV foci (p = 0.913) and the presence or absence of ablation (p = 0.812) in the residual RI-nPVF group., Conclusions: Among paroxysmal AF patients, the presence of residual RI-nPVF was associated with higher AF recurrence compared to residual OTI-nPVF. Furthermore, within residual RI-nPVF subgroup, non-PV foci inducibility or ablation of some residual RI-nPVF did not affect ablation outcome., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: It has not been fully elucidated which patients with persistent atrial fibrillation (PerAF) should undergo substrate ablation plus pulmonary vein isolation (PVI). This study aimed to identify PerAF patients who required substrate ablation using intraprocedural assessment of the baseline rhythm and the origin of atrial fibrillation (AF) triggers., Methods and results: This was a post hoc subanalysis using extended data of the EARNEST-PVI trial, a prospective multicenter randomized trial comparing PVI-alone and PVI-plus (i.e., PVI with added catheter ablation) arms. We divided 492 patients into 4 groups according to baseline rhythm and the location of AF triggers before PVI: Group A (n=22), sinus rhythm with pulmonary vein (PV)-specific AF triggers (defined as reproducible AF initiation from PVs only); Group B (n=211), AF with PV-specific AF triggers; Group C (n=94), sinus rhythm with no PV-specific AF trigger; Group D (n=165), AF with no PV-specific AF trigger. Among the 4 groups, only in Group D (AF at baseline and no PV-specific AF triggers) was arrhythmia-free survival significantly lower in the PVI-alone than PVI-plus arm (P=0.032; hazard ratio 1.68; 95% confidence interval 1.04-2.70)., Conclusions: Patients with sinus rhythm or PV-specific AF triggers did not receive any benefit from substrate ablation, whereas patients with AF and no PV-specific AF trigger benefited from substrate ablation.

Background: The optimal duration of atrial fibrillation (AF) persistence for predicting poor outcomes after catheter ablation of long-standing AF (LsAF) and the best ablation strategy for these patients remain unclear., Objective: We aimed to assess the impact of the duration of AF persistence on outcomes after catheter ablation of AF., Methods: We analyzed the Efficacy of Pulmonary Vein Isolation Alone in Patients with Persistent Atrial Fibrillation (EARNEST-PVI) trial data comparing pulmonary vein isolation (PVI) alone (PVI-alone) with additional linear ablation or defragmentation (PVI-plus) in persistent AF (PerAF). Patients who received catheter ablation by contact force-sensing catheter were enrolled in the study. In patients with LsAF, the optimal cutoff duration of AF persistence was evaluated. With use of the threshold, patients with LsAF were divided into 2 groups and compared with PerAF <1 year for arrhythmia-free survival after a 3-month blanking period., Results: The optimal cutoff duration was 2.4 years. Of 458 patients, arrhythmia-free survival rates for LsAF 1-2.4 years were comparable to those of PerAF (hazard ratio [HR], 1.01; 95% CI, 0.67-1.52). However, LsAF >2.4 years had a higher recurrence risk than PerAF (HR, 2.22; 95% CI, 1.42-3.47). In LsAF >2.4 years, the PVI-plus strategy showed advantages over the PVI-alone strategy (HR, 0.36; 95% CI, 0.14-0.89). However, the interaction effect between LsAF 1-2.4 years and LsAF >2.4 years did not reach statistical significance (P = .116)., Conclusion: Whereas LsAF 1-2.4 years has similar outcomes to those of PerAF, LsAF >2.4 years was linked to higher arrhythmia recurrence risks. For LsAF >2.4 years, the PVI-plus strategy showed a potential to be superior to the PVI-alone strategy., Competing Interests: Disclosures Drs Minamiguchi, Dohi, Nakatani, Hikoso, and Sakata have received grants from Medtronic, Johnson & Johnson, and Abbott during the conduct of the study. Other authors have nothing to disclose related to the submitted work. Conflict of interest outside the submitted work is found in a supplemental file., (Copyright © 2024 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

A case of successful catheter ablation of paroxysmal atrial fibrillation and atrial tachycardia is reported. After pulmonary vein isolation, atrial tachycardia was induced by the use of isoproterenol and burst pacing from the catheter in the right atrium. An attempt was made to create a three-dimensional (3D) map of the atrial tachycardia, but the atrial tachycardia was terminated in the middle of the mapping. The 3D map was insufficient but indicated that the superior vena cava was involved in the circuit. When the intracardiac electrograms were reviewed, it was found that the atrial tachycardia was initiated with orthodromic capture of superior vena cava potentials and it was considered that the atrial tachycardia involved the superior vena cava-right atrium junction. Accordingly, superior vena cava isolation was performed. After that, atrial fibrillation and atrial tachycardias were not induced by the use of isoproterenol and burst pacing. In this case, an intracardiac electrogram at the time of induction of the tachycardia was helpful for understanding the circuit of the tachycardia., (© 2024. The Author(s), under exclusive licence to Springer Medizin Verlag GmbH, ein Teil von Springer Nature.)

Pulmonary vein isolation (PVI) causes changes in P-wave parameters. However, the difference in changes in P-wave parameters including P-wave vector magnitude (Pvm) between radiofrequency catheter ablation (RFCA) and cryoballoon ablation (CBA) remains unknown. Paroxysmal atrial fibrillation (PAF) patients who underwent only PVI were enrolled. Pvm was calculated by the square root of the sum of the squared P-wave amplitude in leads II and V6 and one-half of the P-wave amplitude in V2. The patients were divided into 2 groups: RFCA and CBA. ΔPvm was calculated as ΔPvm (mV) = (Pvm at pre-PVI)-(Pvm at post-PVI). The following factors were evaluated: (1) differences in the ΔPvm between the 2 groups, (2) relation between late arrhythmia recurrence and ΔPvm in RFCA and CBA groups, and (3) the impact of relevant factors on ΔPvm. The study population included a total of 426 patients with PAF (RFCA, 167 patients; CBA, 259 patients). ΔPvm was significantly larger in CBA than in RFCA (p <0.001). Kaplan-Meier analysis showed late arrhythmia recurrence was significantly higher in patients with low ΔPvm (<0.019 mV) than high ΔPvm (≥0.019 mV) in RFCA (Log-rank p <0.001), and low ΔPvm (<0.033 mV) than high ΔPvm (≥0.033 mV) in CBA (Log-rank p <0.001). Multiple regression analysis showed that CBA and heart rate change were independently and significantly associated with ΔPvm (p <0.001 and p <0.001, respectively). In conclusion, ΔPvm was significantly larger in CBA than RFCA during procedure. Low ΔPvm had a higher risk of late arrhythmia recurrence in RFCA and CBA., Competing Interests: Declaration of competing interest The authors have no competing interests to declare., (Copyright © 2024 Elsevier Inc. All rights reserved.)

The impact of the P-wave morphology on clinical outcomes postcatheter ablation (post-CA) and recurrent arrhythmia characteristics or electrophysiologic findings in patients with paroxysmal atrial fibrillation (PAF) remains unclear. Patients with PAF who underwent cryoballoon ablation were enrolled. In 12-lead electrocardiography recorded within 1 month before CA, the P-wave duration (Pd) and P-wave vector magnitude (Pvm) (square root of the sum of the squared P-wave amplitude in leads II, V 6 , and one-half of the P-wave amplitude in V 2 ) were measured and divided into 2 groups: patients with high and low Pd/Pvm based on a statistically calculated cut-off value. We evaluated the incidence of late recurrence of atrial fibrillation (LRAF), myocardial injury (high-sensitive troponin I), and the electrophysiologic findings in repeat ablation sessions. This study included 269 patients with PAF. The median follow-up duration was 697 days. The cut-off value of the Pd/Pvm for predicting LRAF was 740.7 ms/mV (area under the curve = 0.81, sensitivity = 58.2%, and specificity = 89.6%). Multivariable Cox proportional hazards analysis showed that high Pd/Pvm (>740.7 ms/mV) was significantly associated with LRAF (p <0.001). The high-sensitive troponin I level was significantly lower, and the ratio of DR-FLASH score >3 was significantly higher in those with high than low Pd/Pvm (p = 0.044 and p = 0.002, respectively). In the repeat ablation sessions, the Pd/Pvm in patients with atrial tachycardia-induced or spontaneously occurring during the repeat CA sessions was significantly higher than in those without (p = 0.009). There was a significant difference between the Pd/Pvm and low-voltage area (p <0.001). In conclusion, the Pd/Pvm is significantly associated with LRAF after cryoballoon ablation in patients with PAF and predicts left atrial low-voltage areas and atrial tachycardia inducibility., Competing Interests: Declaration of Competing Interest The authors have no competing interests to declare., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: Mitral regurgitation (MR) is associated with an increased risk of developing atrial fibrillation (AF) and high AF recurrence ratio after ablation. Left atrial appendage (LAA) is involved in left atrium (LA) pressure modulation and LAA peak flow velocity (LAAV) is validated as an indicator of LA contractile and reservoir function. LA function is related to the MR pathology, but the relationship between LAAV and improvement in MR after ablation remains unknown., Methods: The present study included AF patients with moderate or severe MR from the Osaka Rosai Atrial Fibrillation ablation (ORAF) registry. We evaluated MR severity one-year post-ablation and assigned the patients based on MR improvement (at least a one-grade improvement in MR over one year) and investigated the impact of the relevant factors, including LAAV, on MR improvement., Results: This study population included a total of 289 patients [paroxysmal AF (PAF), 112 patients; persistent AF (PerAF), 177 patients]. Kaplan-Meier analysis demonstrated that the patients with MR improvement had a significantly lower risk of late arrhythmia recurrence than those without (log-rank p < 0.001). MR improvement was observed in 56.3 % (63/112) of PAF patients and 55.4 % (98/177) of PerAF patients. Multiple regression analysis showed that LAAV was an independent and significant determinant of MR improvement post-ablation in both PAF and PerAF patients (p = 0.037 and p = 0.018, respectively), in addition to age and hemoglobin in PerAF patients (p = 0.045 and p = 0.048, respectively)., Conclusion: LAAV can predict an improvement in MR after catheter ablation in both PAF and PerAF patients., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Purpose: Ablation index (AI)-guided ablation improves the incidence of arrhythmia recurrence as compared to conventional contact force (CF)-guided ablation. The aim of this study was to elucidate the differences in the biomarkers associated with myocardial injury and inflammation between conventional CF-guided and AI-guided ablation., Methods: Atrial fibrillation (AF) patients who underwent pulmonary vein isolation (PVI) from the Osaka Rosai Atrial Fibrillation ablation (ORAF) registry were enrolled. We divided the patients into two groups: conventional CF-guided PVI (CF group) and AI-guided PVI (AI group). The differences in biomarkers associated with myocardial injury and inflammation, and long-term durability of PVI between the two groups were evaluated., Results: This study population included a total of 794 patients (CF-guided, 241 patients; AI-guided, 553 patients). Total application time was significantly shorter, and total application number was significantly smaller in AI than CF group. High-sensitive troponin I (hs-TnI) post-ablation was significantly higher in AI than CF group (p < 0.001), even after taking the total application number and total application time into consideration. No significant differences in inflammatory markers changes from pre- to post-ablation were observed between the two groups. AI-guided ablation was significantly associated with the hs-TnI post-ablation by multiple regression analysis. The PV reconnection ratio was significantly smaller in AI than CF group (p = 0.037)., Conclusions: AI-guided ablation had the ability to create larger lesions than CF-guided ablation despite no increase in inflammation and achieved the better PVI durability than that of CF-guided., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The impact of cryoballoon ablation (CBA) for atrial fibrillation (AF) in patients with enlarged left atrium (E-LA) has not been sufficiently clarified. A total of 306 patients underwent an initial CBA for paroxysmal AF between February 2017 and March 2022 in our hospital. These patients were categorized into 2 groups according to the preprocedural left atrium (LA) diameter (LAD): E-LA group with LAD ≥40 mm and normal LA (N-LA) group with LAD <40 mm. We compared late recurrence (LR, defined as a recurrence of atrial tachyarrhythmia more than 3 months after the ablation) between the 2 groups. In addition, we made a further classification of the E-LA group into a severely E-LA (SE-LA) group with LAD ≥50 mm and mildly enlarged LA (ME-LA) group with LAD <50 mm and compared LR in the SE-LA, ME-LA, and N-LA groups. In the patients who experienced a second ablation procedure owing to LR, subsequent recurrences were also evaluated. After initial CBA, there was no significant difference in recurrence-free survival between E-LA and N-LA groups (p = 0.447). In contrast, the SE-LA group showed the lowest incidence of recurrence-free survival in the SE-LA, ME-LA, and N-LA groups (p = 0.012). However, when we analyzed recurrences after the ablation including second ablation procedure, there were no significant differences in recurrence-free survival among these 3 groups (p = 0.103). In conclusion, patients with paroxysmal AF with enlarged LA showed favorable outcomes compared with those with N-LA after CBA., Competing Interests: Declaration of Competing Interest The authors have no competing interests to declare., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: An ablation index (AI)-guided pulmonary vein isolation (PVI) or 2nd generation cryoballoon (CB)-PVI has been shown to reduce the atrial fibrillation (AF) burden by 99% despite the absence of ablation of non-pulmonary vein (PV) triggers in patients with paroxysmal AF. The purpose of this study was to investigate the effects of PVI alone strategy using 2nd generation CB compared with AI-guided PVI with an additional induction test and subsequent AF trigger ablation., Methods and Results: We investigated 223 patients with symptomatic paroxysmal AF who underwent an initial PVI between August 2018 and August 2020. The study patients were divided into 2 groups: CB-PVI without an induction test (CB-PVI alone group, n = 82) and AI-guided PVI with an induction test and subsequent additional ablation of non-PV triggers (AI-PVI plus group, n = 141). In the AI-PVI plus group, a total of 62 non-PV triggers were induced in 38 patients, and non-PV triggers in 22 patients were completely ablated. The procedure time and left atrium dwell time were significantly shorter in the CB-PVI alone group than AI-PVI plus group. There were no significant differences in the incidence of procedural complications between the 2 groups (P = 0.650). The AF free survival rate in the CB-PVI alone group and AI-PVI plus group was 80% vs. 80% at 24 months (P = 0.969)., Conclusions: An PVI alone strategy using advanced generation CB did not differ in the clinical outcomes compared with an AI-guided PVI strategy with an induction test and subsequent ablation of non-PV triggers in the patients with paroxysmal AF., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

The impact of catheter ablation of atrial fibrillation (AFCA) on left ventricular (LV) diastolic function is still unknown. This study aimed to develop a novel risk score to predict LV diastolic dysfunction (LVDD) 12 months after AFCA (12-month LVDD) and to evaluate whether the risk score was associated with cardiovascular events (cardiovascular death, transient ischemic attack/stroke, myocardial infarction, or heart failure hospitalization). We studied 397 patients with nonparoxysmal AF with preserved ejection fraction who underwent initial AFCA (age: 69 years, women: 32%). LVDD was diagnosed if more than 2 of 3 variables (average E/e' ratio >14, septal e' velocity <7 cm/s or lateral e' velocity <10 cm/s, and tricuspid valve regurgitation velocity >2.8 m/s) were present. The 12-month LVDD was observed in 89 patients (23%). A total of 4 preprocedural variables (woman, average E/e' ratio ≥9.6, age ≥74 years, and left atrial diameter ≥50 mm [WEAL]) were identified as predictors of 12-month LVDD on multivariable analysis. We developed a WEAL score. The prevalence of 12-month LVDD increased as WEAL scores increased (p <0.001). There was a statistically significant difference in cardiovascular events-free survival between those at high risk (WEAL score: 3 or 4) and those at low risk (WEAL score: 0, 1, or 2). (86.6% vs 97.2%, log-rank p = 0.009). The WEAL score before AFCA is useful to predict 12-month LVDD after AFCA in patients with nonparoxysmal AF with preserved ejection fraction and is associated with cardiovascular events after AFCA., Competing Interests: Declaration of Competing Interest The authors have no conflicts of interest to declare., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Introduction: Little has been reported on the predictors and outcomes of improvement of tricuspid regurgitation (TR) after radiofrequency catheter ablation (RFCA) for persistent atrial fibrillation (AF)., Methods: We enrolled 141 patients with persistent AF and moderate or severe TR assessed by transthoracic echocardiography (TTE) who underwent an initial RFCA between February 2015 and August 2021. These patients underwent follow-up TTE at 12 months after the RFCA, and were categorized into two groups based on the improvement (defined as at least one-grade improvement of TR) and non-improvement of TR: IM group and Non-IM group, respectively. We compared the patient characteristics, ablation procedures, and recurrences after the RFCA between the two groups. In addition, we examined the major event (defined as admission for heart failure or all-cause death) more than 12 months after the RFCA., Results: IM group consisted of 90 patients (64%). A multivariate analysis revealed that age <71 years old and absence of late recurrence (LR, defined as recurrence of atrial tachyarrhythmia between 3 and 12 months after the RFCA) were independently associated with the improvement of TR after the RFCA. Furthermore, IM group had the higher incidence of major event-free survival than Non-IM group., Conclusions: Relatively young age and absence of LR were good predictors of improvement of TR after the RFCA for persistent AF. In addition, the improvement of TR was related to better clinical outcomes., (© 2023 Wiley Periodicals LLC.)

Background: ST-segment depression suggests the presence of coronary artery disease (CAD) during sinus rhythm, but the clinical significance, including the outcomes after catheter ablation (CA), in atrial fibrillation (AF) patients remain unknown., Methods: The present study included persistent AF (PerAF) patients from the Osaka Rosai Atrial Fibrillation ablation (ORAF) registry who underwent an initial ablation and had no history of CAD. We assigned the patients based on the presence of ST-segment depression before CA and evaluated the impact of relevant factors on ST-segment depression and the relationship between ST-segment depression, including leads locations (anterior leads, inferior leads, and lateral leads) or depression type (upsloping, horizontal, and downsloping) or the degree of ST-segment depression and late recurrence of AF (LRAF)., Results: This study population included a total of 551 patients of whom 189 had ST-segment depression. The median follow-up duration was 397 days and LRAF occurred in 195 patients. By multiple regression analysis, diabetes mellitus, hemoglobin, brain natriuretic peptide, left ventricular ejection fraction, and left atrial diameter were significant determinants of ST-segment depression before CA. Kaplan-Meier analysis demonstrated that the patients with ST-segment depression had a significantly greater risk of LRAF than those without (p < 0.001). Multivariate Cox proportional hazards analysis showed ST-segment depression was independently and significantly associated with a higher risk of LRAF (p < 0.001). The patients with ST-segment depression ≥0.15 mV had a significantly higher risk of LRAF than those with ST-segment depression ≥0.15 mV (p < 0.001). No significant differences among the ST-segment depression lead locations and ST-segment depression type were observed., Conclusion: Non-ischemic ST-segment depression during AF rhythm was significantly associated with LRAF post CA in PerAF patients., Competing Interests: Declaration of competing interest None., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Little has been reported on the predictors of maintenance of sinus rhythm (SR) after radiofrequency catheter ablation (RFCA) for long-standing persistent atrial fibrillation (AF). We enrolled 151 patients with long-standing persistent AF (defined as AF lasting more than 12 months) who underwent an initial RFCA between October 2014 and December 2020 in our hospital. These patients were categorized into 2 groups on the basis of the absence and presence of the late recurrence (LR, defined as a recurrence of atrial tachyarrhythmia between 3 and 12 months after RFCA): SR group and LR group. The SR group comprised 92 patients (61%). In the univariate analysis, there were significant differences in gender and preprocedural average heart rate (HR) between the 2 groups (p = 0.042 and p = 0.042, respectively). A receiver operating characteristics analysis revealed that a cut-off value of preprocedural average HR to predict the maintenance of SR was 85 beats/min (sensitivity: 37%, specificity: 85%, area under curve: 0.58). A multivariate analysis showed that preprocedural average HR ≥85 beats/min was independently associated with the maintenance of SR after RFCA (odds ratio 3.30, 95% confidence interval 1.47 to 8.04, p = 0.003). In conclusion, a relatively high preprocedural average HR might be a prognostic factor of maintenance of SR after RFCA for long-standing persistent AF., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Little has been reported on the impact of radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF) in patients with left atrial enlargement (LAE). A total of 706 patients underwent an initial RFCA for AF between September 2014 and September 2019 in our hospital. These patients were categorized into two groups according to the pre-procedural left atrial diameter (LAD) measured by transthoracic echocardiography (TTE): LAE group with LAD ≥ 50 mm and non-LAE group with LAD < 50 mm. We compared the patient characteristics, ablation procedures, and late recurrence of AF (LRAF, defined as a recurrence of atrial tachyarrhythmia between 3 and 12 months after the RFCA) between the two groups. In addition, we performed follow-up TTE at 12 months after RFCA and investigated the factors associated with left atrium (LA) reverse remodeling in each group. LAE group and non-LAE group consisted of 155 and 551 patients, respectively. There were no significant differences in ablation procedures, procedure-related complications, and the incidence of LRAF between the two groups. Furthermore, non-PAF was identified as an independent predictor of LA reverse remodeling in LAE group by multiple regression analysis (P = 0.020). RFCA might be an effective and safe procedure even in patients with LAD ≥ 50 mm, using the contemporary 3D-guided mapping and ablation technologies. Moreover, RFCA can lead to LA reverse remodeling in 1 year if they have non-PAF before ablation., (© 2022. Springer Japan KK, part of Springer Nature.)

Background: Although much has been discussed about the early recurrence of atrial fibrillation (ERAF) after cryoballoon ablation (CBA), the clinical impact of very early recurrence of atrial fibrillation (VERAF) after CBA remains unclear. This study aimed to investigate the impact of VERAF after CBA., Methods: We enrolled 236 consecutive patients who underwent an initial CBA for paroxysmal atrial fibrillation between February 2017 and December 2020 in our hospital. These patients were categorized into three groups: VERAF group who experienced an initial recurrence of atrial tachyarrhythmia within 48 h after CBA, late-ERAF (LERAF) group who experienced an initial recurrence of atrial tachyarrhythmia between 48 h and 3 months after CBA, and non-ERAF (NERAF) group who did not experience a recurrence of atrial tachyarrhythmia within 3 months after CBA. We investigated the late recurrence of AF (LRAF, defined as recurrence of atrial tachyarrhythmia more than 3 months after CBA), and the incidence of non-pulmonary vein (PV) triggers in the patients who experienced a repeat ablation procedure due to LRAF., Results: VERAF group had a higher incidence of freedom from LRAF than LERAF group (p = 0.032) and a lower incidence of freedom from LRAF than NERAF group (p = 0.002). Moreover, VERAF group had the highest incidence of non-PV triggers at repeat ablation procedure among the three groups (p = 0.003)., Conclusions: While ERAF was a predictor of LRAF, VERAF was less related to LRAF among the patients with ERAF after CBA. Furthermore, VERAF might be associated with non-PV triggers., (© 2022 Wiley Periodicals LLC.)

At present, it remains unclear whether the effect on cryoinjury can be strongly exerted by contact of the balloon with the pulmonary vein (PV) ostium. The present study included 204 paroxysmal atrial fibrillation (PAF) patients who underwent an initial pulmonary vein isolation (PVI) using a cryoballoon from the Osaka Rosai Atrial Fibrillation ablation (ORAF) registry. The total balloon contact angle was measured from the equator line (sum of the angles of the upper side and bottom side in all PVs) under fluoroscopic imaging. The patients were stratified into three tertile groups according to the total balloon contact angle. We evaluated the relationship between the total balloon contact angle and clinical outcomes, including the value of acute myocardial injury marker (high-sensitive cardiac troponin I [hs-TnI]), arrhythmia recurrence, and PV reconnections in the repeated ablation. The total balloon contact angle was significantly associated with the hs-TnI value among the tertile groups (p < 0.001) and a multiple regression analysis showed that the total balloon contact angle significantly correlated with the hs-TnI value (standardized beta-coefficient = 0.572, p < 0.001). The balloon contact angle in PVs with PV reconnections was significantly lower than in those without (p = 0.044), while no significant differences in the recurrence of atrial fibrillation among the tertile groups were observed in the enrolled patients. The total balloon contact angle was significantly associated with the acute myocardial injury marker, hs-TnI. The total balloon contact angle was significantly associated with PV reconnections after cryoballoon ablation in patients who underwent a repeat ablation., (© 2022. Springer Japan KK, part of Springer Nature.)

Purpose: Early recurrence of atrial tachyarrhythmias (ERAT) cause various symptoms and predict worse outcomes after pulmonary vein isolation (PVI). This study aimed to clarify whether ablation index (AI)-guided PVI, which is a novel technology of radiofrequency ablation, could reduce ERAT as compared to conventional contact force (CF)-guided PVI., Methods: Consecutive atrial fibrillation (AF) patients who underwent initial PVI from September 2014 to August 2019 were enrolled. We divided the patients into two groups: patients who underwent AI-guided PVI (AI group) and those who underwent CF-guided PVI (CF group). Using propensity score matching (PSM), we adjusted for the patient backgrounds. We compared the incidence of ERAT and late reconnection rate of isolated pulmonary veins (PVs) during second session between the two groups. ERAT was defined as any atrial tachyarrhythmias ≥ 30 s during a 90-day blanking period., Results: A total of 697 AF patients (paroxysmal 51%) were enrolled. After the PSM, both groups included 229 patients. The incidence of ERAT was significantly lower in the AI group than that in the CF group (21.5% vs. 36.1%, P < 0.001). Total 118 patients (25.7%) experienced late recurrence of atrial tachyarrhythmias (LRAT) after blanking period. LRAT free survival rate was significantly higher in patients without ERAT than those with ERAT (88.1% vs. 42.0%, P < 0.001). The rate of PV reconnection was lower in the AI group than that in the CF group (45.8% vs. 71.4%, P = 0.028). Multivariate analysis demonstrated that AI-guided PVI was independently correlated with ERAT (OR = 0.415, 95%CI = 0.269-0.639, P < 0.001)., Conclusions: AI-guided PVI can reduce ERAT as compared to conventional CF-guided PVI., (© 2021. Springer Science+Business Media, LLC, part of Springer Nature.)

Introduction: Local impedance (LI) drop during radiofrequency (RF) application is monitored to assess the lesion formation. Recently, a novel ablation catheter has been introduced to clinical setting, which is capable of monitoring LI and catheter contact parameters including contact force (CF) and contact angle (CA). This study aimed to clarify the correlation between LI drop and catheter contact parameters., Methods and Results: This prospective study included 15 paroxysmal atrial fibrillation (AF) patients who underwent initial pulmonary vein isolation (PVI). First-pass encircling point-by-point PV ablation was performed by using a 4.5-mm irrigated ablation catheter, with monitoring LI, CF, and CA. RF energy was applied for 30 s at each site with 30 W. Stable ablation points were analyzed to examine the correlation between LI drop and catheter contact parameters. Among 903 ablation points, 499 stable ablation points (55.2%) were analyzed. CA showed good correlation with LI drop (ρ = 0.418, p < .001). Maximum CF, minimum CF, average CF, and initial CF all showed weak correlation with LI drop (ρ = 0.201, p < .001; ρ = 0.224, p < .001; ρ = 0.258, p < .001; and ρ = 0.212, p < .001, respectively). Multivariate analysis demonstrated that CA was an independent factor of LI drop among the catheter contact parameters (β = 0.139, 95% CI = 0.111-0.167, p < .001). The LI drop in the blocked segments was significantly higher than that in the electrical conduction gap segments (27.3 ± 9.8 vs. 19.6 ± 6.4 Ω, p < .001) CONCLUSION: In clinical PVI use, both CF and CA were correlated with LI drop. More parallel CA could induce higher LI drop, which may lead to effective lesion formation., (© 2022 Wiley Periodicals LLC.)

Radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) causes myocardial injury and induces high-sensitive cardiac troponin I (hs-TnI) release into the systemic circulation. Several factors are considered to be associated with myocardial injury after ablation, but few studies showed the relationship between the value of myocardial injury marker after the RFCA and relevant factors. AF patients who underwent primary RFCA were enrolled from the Osaka Rosai Atrial Fibrillation ablation (ORAF) registry. The relationship between hs-TnI after the RFCA and PV reconnection (PVR) was evaluated. The impact of relevant factors, including baseline patient characteristics, detail of procedure on myocardial injury was investigated. This study included 407 patients (median age was 71 years, the ratio of female was 30.7%). Late arrhythmia recurrence was observed in 111 patients (27.3%) and 66 patients were underwent repeated ablation. PVR was observed in 33 patients (50.0%). The hs-TnI level was significantly lower in the patients with PVR than those without PVR (1.150 ng/ml vs 1.921 ng/ml, p = 0.040). Paroxysmal AF and age were significantly associated with acute myocardial injury after the RFCA (standardized beta coefficient = 0.206 and p < 0.001, standardized beta coefficient = - 0.114 and p = 0.043, respectively). The hs-TnI after RFCA was significantly higher in PAF patients than PerAF (p < 0.001), even if application number and total application time were taken into consideration. Acute myocardial injury after RFCA was significantly lower in the patients with PVR than those without PVR. Age and AF type were significantly and strongly associated with acute myocardial injury after the RFCA., (© 2021. Springer Japan KK, part of Springer Nature.)

Background: The detailed electrophysiological characteristics of atrial fibrillation (AF) initiating non-pulmonary vein (PV) triggers excluding origins from the superior vena cava (SVC) and left atrial posterior wall (LAPW) (Non-PV-SVC-LAPW triggers) remain unclear. This study aimed to clarify the detailed electrophysiological characteristics of non-PV-SVC-LAPW triggers., Methods: Among 446 AF ablation procedures at 2 institutions, patients with reproducible AF initiating non-PV-SVC-LAPW triggers were retrospectively enrolled. The trigger origin was mapped using the self-reference mapping technique. The following electrophysiological parameters were evaluated: the voltage during sinus rhythm and at the onset of AF at the earliest activation site, coupling interval of the trigger between the prior sinus rhythm and AF trigger, and voltage change ratio defined as the trigger voltage at the onset of AF divided by the sinus voltage., Results: Detailed electrophysiological data were obtained at 28 triggers in 21 patients. The median trigger voltage at the onset of AF was 0.16mV and median trigger coupling interval 182msec. Normal sinus voltages (≧0.5mV) were observed at 16 triggers and low voltages (<0.5mV) at 12 triggers. The voltage change ratio was significantly lower for the normal sinus voltage than low sinus voltage (0.20 vs. 0.60, p = 0.002). The trigger coupling intervals were comparable between the normal sinus voltage and low sinus voltage (170ms vs. 185ms, p = 0.353)., Conclusions: The trigger voltage at the onset of AF was low, regardless of whether the sinus voltage of the trigger was preserved or low., Competing Interests: The authors have declared that no competing interests exist.

Background: Little has been reported on the impact of very early recurrence of atrial fibrillation (VERAF) after radiofrequency catheter ablation (RFCA)., Methods: We enrolled 201 consecutive patients who underwent an initial RFCA of atrial fibrillation (AF) between September 2014 and April 2019 in our hospital and experienced early recurrence of AF (ERAF, defined as recurrence of atrial tachyarrhythmia within 3 months after RFCA). These patients were categorized into three groups: Group A who experienced recurrence of atrial tachyarrhythmia only within 48 h after RFCA, Group B who experienced recurrence of atrial tachyarrhythmia both within 48 h and between 48 h and 3 months after RFCA, and Group C who experienced the first recurrence of atrial tachyarrhythmia between 48 h and 3 months after RFCA. We compared the patient characteristics, ablation procedure and procedure-related complications, and clinical outcomes among the three groups. In addition, we investigated the pulmonary vein (PV) reconnections in the patients who experienced a repeat ablation procedure due to late recurrence of AF (LRAF, defined as recurrence of atrial tachyarrhythmia between 3 and 12 months after RFCA)., Results: The Group A, B, and C consisted of 54, 40, and 107 patients, respectively. The inflammatory markers on the second day of RFCA were significantly higher in Group A. Moreover, Group A had a lower incidence of LRAF (p < 0.001) and PV reconnections at repeat ablation procedure (p = 0.023)., Conclusions: VERAF may have better clinical outcomes including lower incidence of LRAF and PV reconnections among patients with ERAF., Competing Interests: Declaration of Competing Interest None., (Copyright © 2021. Published by Elsevier Ltd.)

Background: Cryoballoon ablation (CBA) and laser balloon ablation (LBA) were developed as alternatives to conventional radiofrequency ablation for paroxysmal atrial fibrillation (PAF). Pathological findings after ablation such as myocardial injury and inflammation are thought to be different between CBA and LBA. However, the different impact of myocardial injury and inflammation after ablation on short- and mid-term outcomes remains unclear., Methods: Consecutive PAF patients who underwent CBA and LBA were enrolled from the Osaka Rosai Atrial Fibrillation ablation (ORAF) registry. The difference of the acute myocardial injury marker (hs-TnI), and changes of inflammation markers (C reactive protein; ΔCRP, and white blood cell; ΔWBC) after catheter ablation and the difference of the short-term (within 3 months after ablation) and mid-term (from 3 months to 6 months after ablation) outcomes were evaluated between the two groups., Results: The CBA and LBA groups consisted of 55 and 56 patients, respectively. After propensity score matching, CBA and LBA groups consisted of 37 patients, respectively. Hs-TnI value was significantly higher in CBA than LBA group, while ΔCRP and ΔWBC were significantly higher in LBA than CBA group. In the propensity score-matched pairs, the LBA group had a significantly greater risk of short-term arrhythmia recurrence than the CBA group, whereas no significant difference of mid-term arrhythmia recurrence were found between the two groups., Conclusion: Myocardial injury and inflammation status differ between CBA and LBA groups. LBA group had stronger inflammation after ablation and had a significantly greater risk of short-term arrhythmia recurrence after PVI than CBA group., Competing Interests: Declaration of competing interest None., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Although several studies have suggested that catheter ablation (CA) of atrial fibrillation (AF) can improve left ventricular ejection fraction (LVEF) in patients with heart failure with reduced ejection fraction (HFrEF), the predictor of improvement of LVEF is unclear. A total of 401 patients with persistent AF underwent an initial CA between September 2014 and October 2019 in our hospital. Among them, we analyzed consecutive patients with moderately or severely reduced LVEF (< 50%) measured by transthoracic echocardiography (TTE) within 2 months before CA and underwent follow-up TTE during sinus rhythm at 6 months or more after CA. These patients were categorized into two groups: improve group (I group) with the absolute improvement of LVEF ≥ 10% at follow-up TTE, and non- improve group (NI group) with the absolute improvement of LVEF < 10% at follow-up TTE. We compared patient characteristics, ablation procedures, and clinical outcomes between the two groups. 81 patients were analyzed, and I group consisted of 48 patients (59%). In the univariate analysis, absence of ischemic cardiomyopathy, left ventricular end-diastolic diameter (LVEDD), and absence of recurrence of AF between 3 and 6 months after CA were associated with improvement of LVEF. A receiver operating characteristics analysis determined the suitable cut-off value for LVEDD was 53 mm (sensitivity: 62.2%, specificity: 86.2%, area under curve: 0.762). A multivariate analysis showed that LVEDD < 53 mm was independently associated with improvement of LVEF (odds ratio 2.58, 95% confidence interval 1.29-6.12; P = 0.021). In conclusion, LVEDD < 53 mm might be an independent predictor of improvement of LVEF after CA of persistent AF in HFrEF patients.

Background: It is unclear whether balloon size can influence lesion formation. The aim of this study was to evaluate the impact of balloon size on lesion formation during laser balloon procedures in an in vitro model., Methods and results: Laser energy was applied to chicken muscle using a first generation laser balloon. Laser ablation was performed with 2 different balloon sizes (18 mm and 32 mm) using 2 different power settings (12 W/20 s and 8.5 W/20 s) on the chicken muscle. The lesion characteristics, including maximum lesion depth, maximum lesion diameter, surface diameter and depth at maximum diameter, were compared between the 18-mm and 32-mm balloon groups at 12 W/20 s and 8.5 W/20 s, respectively. We created 40 lesions using laser energy at 12 W/20 s and 80 lesions at 8.5 W/20 s. At both power settings, the maximum lesion depth and the depth at the maximum diameter were larger in the 18-mm than in the 32-mm balloon group. At both power settings, the maximum lesion diameter and the surface diameter were smaller in the 18-mm than in the 32-mm balloon group., Conclusions: The balloon size could affect the lesion formation during laser balloon ablation. The lesion with the larger balloon size was wider and shallower than the lesion with the smaller balloon size.

Right bundle branch block (RBBB) is one of the most frequent alterations of the electrocardiogram. Several studies have shown that RBBB is a risk factor of cardiovascular diseases. However, the clinical outcomes after pulmonary vein isolation (PVI) in patients with RBBB remain unclear. We enrolled consecutive atrial fibrillation (AF) patients who underwent PVI from the Osaka Rosai Atrial Fibrillation (ORAF) registry. We excluded patients with other wide QRS morphologies (left bundle branch block, ventricular pacing, and unclassified intraventricular conduction disturbances) and divided them into 2 groups: RBBB (QRS duration ≥120msec) and No-RBBB (QRS duration <120) groups. We compared the incidence of late recurrence of AF and/or atrial tachycardia (AT) (LRAF) between the 2 groups using a propensity score-matched analysis and evaluated the risk of LRAF using Cox regression model. We finally analyzed 671 consecutive AF patients. The RBBB group consisted of 50 patients (7.5%) and the No-RBBB group of 621 patients. Median follow-up duration was 734 [496, 1,049] days. Hypertension and diabetes mellitus were significantly higher in RBBB group than No-RBBB group. Among the 46 matched patients pairs, Kaplan-Meier analysis demonstrated that RBBB group had a significantly greater risk of LRAF than the No-RBBB group (p = 0.046). The Cox regression model revealed significantly higher risks of LRAF (HR, 2.30; 95% CI, 1.00 to 5.33; p=0.044) in RBBB group compared with No-RBBB group. Non-PV AF triggers were significantly higher in RBBB group than No-RBBB group (p = 0.048). In conclusion, RBBB can be an important predictor of LRAF after PVI., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Various predictors of atrial fibrillation (AF) recurrence have been shown based on the baseline characteristics before catheter ablation (CA). This study aimed to develop a novel scoring system for predicting very late recurrences of AF (VLRAFs) after an initial CA, taking the postprocedural clinical data into account and reassessing VLRAFs in 12-month patients' condition using previously known preprocedural predictors of AF recurrences. We retrospectively studied 327 patients who underwent an initial CA with freedom from AF for over 12 months. We elucidated the predictors of VLRAFs and created a new score to predict VLRAFs in the discovery AF cohort (n = 181). Thereafter, we investigated whether the new scoring system could accurately predict VLRAFs in the validation AF cohort (n = 146). In the discovery AF cohort, VLRAFs were observed in 53 patients (29%) during the follow-up period (mean follow-up duration: 55 months). The univariate and multivariate Cox proportional-hazards model demonstrated that non-pulmonary vein foci, early recurrences of AF (ERAFs), atrial premature contraction (APC) burden ≥ 142/24 hours, and minimum prematurity index of the APCs ≤ 48% were associated with VLRAFs after CA. We created a new scoring system to predict VLRAFs, the n-PReDCt score (non-pulmonary vein: 1 point, early recurrences of AFs (Recurrences of AF in early phase after CA): 1 point, APC burden ≥ 142/24 hours: 1 point, and minimum prematurity index (= Coupling interval) of the APCs of ≤ 48%: 1 point). The n-PReDCt score was significantly associated with VLRAFs by a Kaplan-Meier analysis in the discovery AF and validation AF cohorts (p < 0.0001 and p < 0.0001, respectively)., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Introduction: It has not been clarified how to identify the electrophysiological junction between right atrium (RA) and superior vena cava (SVC). The aim of this study was to identify the electrophysiological RA-SVC junction according to slow conduction or conduction bock and to examine the electrophysiological SVC isolation procedure., Methods: Seventy-three consecutive atrial fibrillation patients who underwent SVC mapping using a CARTO 3 system were enrolled in this study. Slow conduction or conduction block between the RA and SVC was identified by adjusting the lower threshold criteria of the early meets late function and was described as a white line. The SVC isolation was performed along the white line and with pacing maneuvers to confirm direct SVC capture., Results: Activation mapping (1296 ± 631 points) was obtained in 66 patients (90%) in 4.6 ± 1.8 min. Slow conduction or conduction block was observed in all patients. The threshold for detecting slow conduction or conduction block was 24 ± 8 ms. The location of the electrophysiological RA-SVC junction was higher in the anterior portion (anterior-septal, anterior, and anterior-lateral) than in the posterior portion (posterior-septal, posterior, and posterior-lateral) (-2.3 ± 6.2 mm vs. 7.1 ± 6.3 mm, p < .001). The SVC isolation at the electrophysiological RA-SVC junction was successful in all patients without any injury to the sinus node function. Asymptomatic phrenic nerve injury was observed in three patients (4.5%)., Conclusion: In all patients, the electrophysiological RA-SVC junction determined by slow conduction or conduction block was identified and the electrophysiological SVC isolation was performed successfully and safely., (© 2020 Wiley Periodicals LLC.)

Background: The method to perform a precise mapping of non-pulmonary vein (PV) triggers has not been fully investigated. The purpose of this study was to assess the efficacy of self-reference mapping for eliminating non-PV triggers in a large series of patients including the long-term outcomes., Method: Among 446 atrial fibrillation (AF) ablation procedures in 431 patients at 2 institutions, we prospectively enrolled patients who had reproducible non-PV triggers. Non-PV triggers from the left atrial posterior wall (LAPW) and superior vena cava (SVC) were excluded. Ablation procedure and long-term clinical outcomes were evaluated. The origin of non-PV triggers were detected using a self-reference mapping technique, which does not require any other reference catheters. Instead of using signals obtained from a fixed intracardiac catheter as the reference, an operator repeatedly moved a multi-electrode catheter to the earliest site creating a new reference each time to map the non-PV trigger., Results: A total of 32 non-PV triggers excluding origins from the LAPW and SVC were induced in 23 patients. All triggers were mapped using a self-reference mapping technique with 11.0 ± 10.2 min and eliminated by radiofrequency ablation with 10.7 ± 10.0 points application. No major complications were observed. During the follow-up (529 ± 270 days), 18 patients (77%) were free from atrial tachyarrhythmias after a 3-month blanking period. Three patients received additional ablation procedures. No non-PV triggers ablated during the previous procedure were observed., Conclusions: A novel self-reference mapping technique is useful for eliminating non-PV triggers for the short- and long-term outcomes., Competing Interests: Declaration of competing interest The authors declare no conflict of interest for this article., (Copyright © 2020 Elsevier B.V. All rights reserved.)

This study aimed to evaluate the predictors of very late recurrence of atrial fibrillation (VLRAF) after an initial AF catheter ablation (CA) by analyzing the follow-up Holter electrocardiogram. We retrospectively studied patients (n = 253, mean age: 66 years, woman: 30%, paroxysmal AF: 73%) without recurrence of AF within 12 months and the use of antiarrhythmic drugs. In the Holter electrocardiogram analysis, the atrial premature complexes (APCs) burden, the profile of the APCs run and prematurity index of the APCs were evaluated. Fifty-one patients (20%) had VLRAF during the follow-up period (mean follow up: 46 months). Patients with VLRAF had a significantly greater APCs burden (0.318% [0.084 to 1.405] vs 0.132% [0.051 to 0.461], p = 0.022), longer number of APCs run (5 [3 to 11] vs 4 [0 to 7], p = 0.019), and shorter minimum prematurity index of the APCs (47 ± 7 vs 51 ± 6, p = 0.001) than those without VLRAF. The optimal cutoff value for the APCs burden, maximum number of APCs run, and minimum prematurity index of the APCs to predict VLRAF was 0.159%, 10, and 48%, respectively. The minimum prematurity index of the APCs (≤48%) was significantly associated with VLRAF in the multivariate analysis. In conclusion, the minimum prematurity index of the APCs (≤48%) at 12 months after CA was shown to be an independent predictor of VLRAF in patients without antiarrhythmic drugs. Although the index is a very simple parameter automatically calculated by analysis software, it can be an important index for following patients after CA over the long-term., (Copyright © 2020 Elsevier Inc. All rights reserved.)

It is unclear whether uninterrupted oral anticoagulants (OACs) are acceptable in elderly patients as compared to non-elderly patients. This study aimed to assess the clinical impact of an uninterrupted OAC strategy during atrial fibrillation (AF) ablation in elderly patients. We enrolled 439 consecutive patients who underwent AF ablation with an uninterrupted OAC strategy at our institute. The incidence of bleeding and thromboembolic complications during the AF ablation or within 4 weeks after and the anticoagulation status during the AF ablation were compared between the elderly (age ≧ 75, n = 144) and non-elderly groups (n = 295). There were 22 bleeding complications in the elderly group and 31 in the non-elderly group (15% vs. 11%, p = 0.162) and 3 major bleeding complications in the elderly group and 2 in the non-elderly group (2% vs. 0.7%, p = 0.336). Thromboembolic events were observed in 1 patient in the elderly group and 2 in the non-elderly group (0.7% vs. 0.7%, p = 1.000). The ACT at the end of the procedure was longer in the elderly group than in the non-elderly group (350 s vs. 341 s, p = 0.007) and the proportion of a prolonged ACT of > 400 s (27% vs. 18%, p = 0.046) was more frequent in the elderly group than non-elderly group. A propensity score matched population excluding the age and body weight, revealed that the anticoagulation status during AF ablation was comparable between the two groups. Thus, in the patients undergoing AF ablation with uninterrupted OAC strategy, bleeding complications in elderly patients were similar to those in non-elderly patients. The anticoagulation status during the procedure in elderly patients was more prolonged than that in non-elderly patients.

Backgrounds: Several studies have shown the serum high sensitive cardiac troponin I (hs-TnI) a biomarker of myocardium injury, and C-reactive protein (CRP), a biomarker of inflammation, are associated with worse cardiovascular outcomes. We evaluated the relationship between the hs-TnI level in patients with paroxysmal atrial fibrillation (PAF) after pulmonary vein isolation (PVI) and atrial fibrillation (AF) recurrence., Methods and Results: We enrolled 263 consecutive PAF patients who underwent PVI from May 2017 to April 2018. We investigated the difference in the relationship between the myocardial injury marker (serum hs-TnI), inflammatory marker (CRP, white blood cell) at 36 to 48 hours after the PVI, and early or late recurrence of AF (ERAF; <3 months and LRAF; from 3 months to 1 year) between the radiofrequency ablation group (R group) and cryoballoon ablation group (C group). The R group consisted of 147 patients and the C groups consisted of 116 patients. The serum hs-TnI level in R group was significantly lower than in the C group (2.33 vs 5.08 ng/mL; P < .001), while the CRP was significantly higher in the R group than C group (2.02 vs 1.10 mg/dL; P < .001). The incidences of an ERAF/LRAF were similar between the two groups., Conclusion: Cryoballoon ablation may cause more myocardial injury than radiofrequency catheter ablation, on the contrary, radiofrequency catheter ablation, may cause more inflammation than cryoballoon ablation. However, these phenomena may not affect the recurrence of AF after the PVI in patient with PAF., (© 2020 Wiley Periodicals, Inc.)

A 35-year-old woman was referred for treatment of a supraventricular tachycardia. The tachycardia was diagnosed as a slow-fast form of atrioventricular nodal reentrant tachycardia. Radiofrequency ablation targeting the antegrade slow pathway was performed at the posterior septum of the right atrium. After the radiofrequency ablation, ventricular extrastimulus pacing was performed to assess the retrograde slow pathway, which was suggested before the ablation. The prolongation of the VA interval with a 10 ms decrease in the S2 pacing interval was 60 ms and retrograde dual pathways were suspected. However, the HA interval did not change and a prolongation of the VA interval was caused by the prolongation of the VH interval and no additional ablation was required., (Copyright © 2019 Elsevier Inc. All rights reserved.)

A 70-year-old woman was admitted for treatment of supraventricular tachycardia. Ventriculoatrial conduction was revealed through programmed ventricular stimulation; the coronary sinus ostium (CSos) was the earliest atrial activation site. The fast-slow forms of atrioventricular nodal reentrant tachycardia (AVNRT) were induced by ventricular extra-stimuli. During tachycardia, the earliest atrial activation site was located at the bottom of CSos. Radiofrequency (RF) energy application to this site resulted in the delay of local electrical potential, prolongation of tachycardia cycle length, and a shift of the earliest retrograde activation site to the roof of CSos. Subsequent ablation induced a similar shift to the inferior tricuspid annulus and to the right posterior septum. Finally, RF energy application to the right posterior septum resulted in the termination of tachycardia, which was not induced afterward. Multiple shifts in the earliest retrograde atrial activation site along the tricuspid annulus after each slow pathway ablation suggested that annular tissue plays a substantial role as a substrate for AVNRT.