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Epicardial adipose tissue (EAT) has been reported to promote myocardial fibrosis and to affect intracardiac conduction. The PR interval reflects the conduction from the atria to the Purkinje fibers and may be associated with the EAT volume, especially in persistent atrial fibrillation (AF) patients. We aimed to investigate the relationship between the EAT and PR interval in patients with persistent AF. We enrolled 268 persistent AF patients who underwent catheter ablation (CA) and divided the patients into two groups: the normal PR interval group (PR interval less than 200 ms: Group N) and long PR interval group (PR interval 200 ms or more: Group L). We then analyzed the association between the total EAT volume around the heart and PR interval and calculated the ratio of the duration of the P wave (PWD) to the PR interval (PWD/PR interval). Moreover, we investigated whether a long PR interval was associated with the outcomes after ablation. The total EAT volume was significantly larger in Group L than Group N (Group N: 131.4 ± 51.8 ml vs. Group L: 151.3 ± 63.3 ml, p = 0.039). A positive correlation was also observed between the PWD/PR interval and EAT volume in Group L (r = 0.345, p = 0.039). A multivariate analysis also revealed that a long PR interval was independently associated with AF recurrence after CA (hazard ratio [HR] 2.071, p = 0.032). The total EAT volume was associated with a long PR interval, and a long PR interval was a significant risk factor for recurrence after ablation in persistent AF patients., (© 2023. Springer Nature Japan KK, part of Springer Nature.)

We aimed to develop a hemostatic device with physiological evidence that allows ambulation soon after atrial fibrillation (AF) ablation. We measured right femoral vein pressure in 57 participants to clarify why groin post-venipuncture rebleeding often occurs during the transition from supine to sitting under compression bandage application and found that it increased more than threefold when raising the upper body (8.6 ± 4.1 to 27.6 ± 6.9 mmHg; P < 0.001). Based on that data, we created a novel hemostatic belt. Its capability test including 25 participants demonstrated that the belt gave much higher compression pressures on the right groin while sitting than the compression bandage (59.5 ± 14.9 vs. 8.1 ± 4 mmHg; P < 0.001), achieving pressures above the maximum femoral vein pressure in 92% of participants. A randomized trial comparing the belt with compression bandage in 74 AF patients demonstrated that the belt reduced time to ambulation without any rebleeding (340 [92.5-360] vs. 360 [360-360] min; P < 0.001) and satisfied more patients. The novel hemostatic belt provided a much higher compression pressure on the right groin during the sitting position than the conventional compression bandage, achieving a pressure above the maximum femoral vein pressure in 92% of the participants., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: There is a concern about worsening anemia after atrial fibrillation (AF) ablation in anemic patients. We aimed to clarify whether or not patients with anemia who are on an oral anticoagulant therapy are more likely to lose blood after AF ablation., Methods: We studied AF patients in 3 cardiovascular centers who skipped a single dose of a direct oral anticoagulant prior to the ablation, and compared the drop in the hemoglobin level 24 hours after the procedure and bleeding complications between the patients with and without preexisting anemia., Results: We identified 183 (15.7%) patients with anemia at baseline out of 1163 patients. The reduction in the hemoglobin level (-0.39±0.71 vs. -0.93±0.9 g/dL; p<0.001) was smaller in the anemic than non-anemic patients. A fall in the hemoglobin level of ≥2 g/dL, which is a guideline-defined significant hemoglobin drop, was less common in anemic patients (1.6% vs. 11.3%; p<0.001). A female gender [odds ratio (OR) 1.62, confidence interval (CI) 1.07-2.45; p=0.02], persistent or long-standing persistent versus paroxysmal AF (OR 1.67, CI 1.13-2.49; p=0.01), ORBIT score ≥3 (OR 3.5, CI 1.34-8.94; p=0.01), and preexisting anemia (OR 0.02, CI 0.004-0.14; p<0.001) were independently associated with the fall in the hemoglobin level of ≥2 g/dL. No difference was noted in the rate of major bleeding complications (1.6% vs. 1.2%; p=0.72)., Conclusions: Paradoxically, patients with preexisting anemia may be less likely to lose blood following AF ablation., Competing Interests: Declaration of Competing Interest None declared., (Copyright © 2021. Published by Elsevier Ltd.)

Purpose: Thromboembolic or hemorrhagic complications related to atrial fibrillation (AF) ablation are rare, and thus, it is difficult to compare their frequency across different direct oral anticoagulants (DOACs). We aimed to compare the intra-ablation blood coagulability and post-procedural hemoglobin fall as alternatives to those complications across 4 DOACs., Methods: We enrolled AF patients younger than 65 years old in 3 cardiovascular centers who skipped a single dose of apixaban, dabigatran, edoxaban, and rivaroxaban, prior to the ablation. Endpoints included the activated clotting time (ACT), heparin requirement during the ablation, and drop in the hemoglobin level 24 h after the procedure., Results: The time-course curves of the ACT differed significantly across the patients with apixaban (N = 113), dabigatran (N = 130), edoxaban (N = 144), and rivaroxaban (N = 81), with its highest level in the dabigatran group (P < 0.001). The average ACT was greater in the dabigatran group than in the other groups (312.3 ± 34, 334.4 ± 44, 308.1 ± 41, and 305.8 ± 34.7 s; P < 0.001). A significant difference was noted in total heparin requirement across the patient groups (3990.2 ± 1167.9, 3890.4 ± 955.3, 4423.8 ± 1051.6, and 3972 ± 978.7 U/m 2 /h; P < 0.001), with its greatest amount in the edoxaban group. The reduction in the hemoglobin level was similar (- 0.93 ± 0.92, - 0.88 ± 0.79, - 0.89 ± 0.97, - 0.95 ± 1.23 g/dL; P = 0.94). No inter-group difference was noted in the rate of major or minor bleedings (0.9%, 2.3%, 1.4%, and 3.7%; P = 0.51), and no thromboembolic events were encountered., Conclusion: A difference in DOACs may have an impact on intra-ablation anticoagulation; however, it may not be on the procedural blood loss in the setting of a single skip., (© 2020. Springer Science+Business Media, LLC, part of Springer Nature.)

Periprocedural bleeding and thromboembolic events are worrisome complications of catheter ablation for atrial fibrillation (AF). Periprocedural anticoagulation management could decrease the risk of these complications. However, evaluation of the complications from pulmonary vein isolation using cryoballoon related to different anticoagulation strategies is limited. Therefore, we aimed to compare prothrombotic responses as assessed on the basis of D-dimer levels between the uninterrupted and interrupted apixaban therapies during cryoballoon ablation. Ninety-seven consecutive patients with paroxysmal AF scheduled to undergo cryoballoon ablation were randomly assigned in a 1:2 ratio to uninterrupted apixaban therapy (Group 1, n = 32) or interrupted apixaban therapy (Group 2, n = 65). D-Dimer levels were measured immediately before the ablation, at the end of the ablation, and 24 and 48 h after the procedure. No statistical difference was observed in the baseline characteristics between the two groups. The rates of hemorrhagic complications were similar in both groups (major bleeding: 3.1 vs. 1.5%; p = 0.61, and minor bleeding: 3.1 vs. 4.6%; p = 0.73, respectively). No thromboembolic events occurred in either group. However, D-dimer levels 48 h after the ablation increased more markedly following the procedure in Group 2 than in Group 1 (from 0.58 ± 0.16 to 1.01 ± 0.42 μg/mL vs. 0.58 ± 0.20 to 0.82 ± 0.25 μg/mL; p = 0.01). In conclusion, uninterrupted apixaban therapy during the periprocedural period of cryoballoon ablation for AF did not increase the risk of bleeding in this study and might reduce the periprocedural risk of subclinical hypercoagulable state.

Background: Atrial fibrillation (AF) recurrence after radiofrequency catheter ablation (RFCA) still remains a serious issue. Ca2+ handling has a considerable effect on AF recurrence. The histidine-rich calcium-binding protein (HRC) genetic single nucleotide polymorphism (SNP), rs3745297 (T>G, Ser96Ala), is known to cause a sarcoplasmic reticulum Ca2+ leak. We investigated the association between HRC Ser96Ala and AF recurrence after RFCA in paroxysmal AF (PAF) patients., Methods and Results: We enrolled PAF patients who underwent RFCA (N = 334 for screening and N = 245 for replication) and were genotyped for HRC SNP (rs3745297). The patient age was younger and rate of diabetes and hypertension lower in the PAF patients with Ser96Ala than in those without (TT/TG/GG, 179/120/35; 64±10/60±12/59±13 y, P = 0.001; 18.5/ 9.2/8.6%, P = 0.04 and 66.1/50.0/37.1%, P = 0.001, respectively). During a mean 19 month follow-up, 57 (17.1%) patients suffered from AF recurrences. The rate of an Ser96Ala was significantly higher in patients with AF recurrence than in those without in the screening set (allele frequency model: odds ratio [OR], 1.80; P = 0.006). We also confirmed this significant association in the replication set (OR 1.74; P = 0.03) and combination (P = 0.0008). A multivariate analysis revealed that the AF duration, sinus node dysfunction, and HRC Ser96Ala were independent predictors of an AF recurrence (hazard ratio [HR], 1.04, P = 0.037; HR 2.42, P = 0.018; and HR 2.66, P = 0.007, respectively)., Conclusion: HRC SNP Ser96Ala is important as a new genetic marker of AF recurrence after RFCA., Competing Interests: The authors have declared that no competing interests exist.

Introduction: The single nucleotide polymorphism (SNP) rs2106261 in the transcription factor gene ZFHX3 (16q22), a major regulator of inflammation, has been reported linking to atrial fibrillation (AF) by genome-wide association studies. Inflammation is known to be a strong predictor of atrial fibrillation recurrence after ablation, so we examined the association of the ZFHX3 SNP rs2106261 to inflammation marker expression and recurrence after AF ablation., Methods: We genotyped ZFHX3 SNP rs2106261 and compared the minor (T) allele frequency between 362 paroxysmal AF (PAF) patients underwent pulmonary vein isolation (PVI) and 627 non-AF controls. We also analyzed associations between ZFHX3 SNP rs2106261 genotype and recurrence rate after pulmonary vein isolation and the inflammation markers., Results: The minor (T) allele frequency of the ZFHX3 SNP rs2106261 was significantly higher in AF patients than non-AF controls (odds ratio 1.52, p = 2.2×10-5). Multivariable analysis revealed that the minor allele (T) decreased AF recurrence rate after pulmonary vein isolation (hazard ratio 0.53, p = 0.04). Further, neutrophil/lymphocyte (N/L) ratio, C-reactive protein (CRP), and interleukin-6 (IL-6) expression levels were lower in PAF patients with the ZFHX3 SNP rs2106261 minor allele (TT+TC) than in CC patients (N/L ratio: CC 2.22 ± 0.08, TT+TC 1.98 ± 0.06, p = 0.018; CRP: CC 0.103 ± 0.009 mg/dl, TT+TC 0.076 ±0.007 mg/dl, p = 0.016; IL-6: CC 60.3 ± 3.0 pg/ml, TT+TC 52.8 ± 2.3 pg/ml, p = 0.04)., Conclusions: The ZFHX3 SNP rs2106261 minor allele is associated with lower AF recurrence rate after pulmonary vein isolation. Low baseline inflammation conferred by this allele may reduce AF recurrence risk., Competing Interests: The authors have declared that no competing interests exist.

Background: It is uncertain whether rate or rhythm control is more favorable for patients experiencing tachycardia-induced cardiomyopathy (TIC) secondary to rapid atrial fibrillation (AF)., Methods and Results: We compared the electrophysiological and hemodynamic properties and outcome after AF ablation in 20 patients with a history of decompensated TIC who maintained sinus rhythm or had paroxysmal AF (group 1), 32 with a history of decompensated TIC who had persistent or longstanding persistent AF (group 2), 377 without TIC who had paroxysmal AF (group 3), and 225 without TIC who had persistent or longstanding persistent AF (group 4). The corrected sinus node recovery time was more prolonged in group 2 than in groups 1, 3, or 4 (1,066 ± 946 vs. 416 ± 188, 450 ± 322 and 590 ± 329 milliseconds; P < 0.001, respectively). The mean left atrial pressure in group 2 was greater than that in groups 1, 3, or 4 (13.9 ± 6.5 vs. 7.5 ± 3.1, 8.2 ± 4.1 and 10.8 ± 4.2 mmHg; P < 0.001, respectively). The left ventricular ejection fraction assessed after the recovery from the decompensation was more decreased in group 2 than in group 1; however, it almost returned to normal if sinus rhythm was maintained after the AF ablation in group 2. The presence of a history of TIC did not predict an AF recurrence after the ablation., Conclusions: Heart rate control during AF without sinus conversion may result in an incomplete cure of TIC, suggesting the advantages of rhythm control with ablation in patients with TIC., (© 2014 Wiley Periodicals, Inc.)

Aims: Procedural sedation by non-anaesthesiologists with GABAergic anaesthetics has the potential risk of fatal respiratory depression. Dexmedetomidine works its sedative action via α2-adrenergic receptors, and is less associated with respiratory depression. We tested the usability of dexmedetomidine as a procedural sedative during ablation of atrial fibrillation (AF)., Methods and Results: Consecutive patients were randomized to be treated with dexmedetomidine (n = 43) or thiamylal (n = 44) as sedatives during AF ablation. Apnoeic and body movement events were monitored using a novel portable respiratory monitor, the SD-101, during the procedure. Although the majority of the patients receiving dexmedetomidine required rescue sedations with thiamylal, the respiratory disturbance index (RDI) defined as the total number of sleep-disordered breathing events divided by the recording time (10.4 ± 5.1 vs. 18.2 ± 8.1 events/h; P < 0.0001) and movement index defined as the number of body movement events per hour (7.6 ± 6.1 vs. 11.0 ± 5.5 events/h; P = 0.0098) were both significantly lower in the dexmedetomidine arm than in the thiamylal arm. A multivariate linear regression analysis including potential factors revealed that dexmedetomidine vs. thiamylal was solely and independently associated with the RDI (β = -0.62; P = 0.0031). The occurrence of hypotension [9 (21%) vs. 4 (9%); P = 0.14] and bradycardia [4 (9%) vs. 4 (9%); P = 1.0] were similar in the patients with dexmedetomidine and thiamylal., Conclusion: Procedural sedation with dexmedetomidine may assure safety and patient immobility during AF ablation, and therefore may be a potential alternative for that with GABAergic anaesthetics., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2013. For permissions please email: journals.permissions@oup.com.)

We aimed to examine what becomes of the coagulable state when warfarin is interrupted in patients undergoing ablation of atrial fibrillation (AF). We studied 62 patients with a CHADS2 score of 0 or 1 who underwent ablation for paroxysmal AF. Warfarin was discontinued the day before the ablation without heparin-bridging, and intravenous heparin was administered during the procedure in a conventional manner, and warfarin was then resumed after achieving hemostasis of the access site. The international normalized ratio (INR) values or D-dimer levels were measured at five different time points during the periprocedural period, and the periprocedural hemorrhagic and thromboembolic complications were assessed. The INR value constantly decreased after withdrawal of warfarin, and did not recover to the level before its discontinuation at the time of hospital discharge despite a short interruption of warfarin (mean ± SD, 1.75 ± 0.52 to 1.41 ± 0.27, p < 0.0001). However, the D-dimer level continued to increase over a period of 48 h after the ablation in spite of the administration of a sufficient amount of heparin during the procedure and a quick resumption of warfarin (mean ± SD, 0.57 ± 0.19 to 0.85 ± 0.36 μg/mL, p < 0.0001). The INR value measured just before the ablation had a significant inverse correlation to the D-dimer levels assessed just before (r = -0.304), immediately after (r = -0.440), 24 h after (r = -0.442) and 48 h after the ablation (r = -0.463). In conclusion, the risk of hyper-coagulability may increase during the early postprocedural period of AF ablation in patients who were inappropriately anticoagulated with warfarin.

Background: Restless patient is recalcitrant during ablation of atrial fibrillation (AF). We aimed to assess the association between patient movements during AF ablation and its outcome., Methods: We examined the body movement during AF ablation in 78 patients with the use of a novel portable respiratory monitor, the SD-101, which also has the ability to quantify the frequency of body movements., Results: The body movement index, defined as the number of the units of time with body movement events divided by the recording time (11.4 ± 6.5 events/h), was significantly correlated with the ablation time defined as the time from the first point of the ablation to the end of the procedure (1.2 ± 0.3h) (r=0.35; p=0.0014) and a total radiofrequency energy applied (56.6 ± 17.7 kW) (r=0.36; p=0.0015). A multiple linear regression analysis showed that non-paroxysmal AF (β=0.25; p=0.036) and the body movement index (β=0.36; p=0.0019) were independent determinants of the ablation time. The body movement index was similar in patients with and without recurrence of AF., Conclusions: Keeping patients motionless may be important to reduce the procedural duration of AF ablation., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

Some patients with persistent atrial fibrillation (AF) acquire long-term freedom from AF by pulmonary vein (PV) isolation alone. The aim of the present study was to evaluate the characteristics of their atrial substrate.We studied 20 patients with persistent AF to examine the distribution of fractionated atrial potentials (FAP) and that of the anatomic sites of ganglionated plexi (GPs) with vagal reflexes elicited by high frequency stimulation (HFS) with the use of the CARTO system before and after the PV isolation.Both the %FAP area defined as a proportion of the FAP area to the total left atrial area (34.3 ± 10.3 to 21.5 ± 10.2%; P < 0.0001) and number of GP sites with vagal reflexes (4.0 [3.0, 5.0] to 2.0 [1.0, 2.8]; P < 0.0001) were markedly decreased after the PV isolation. Seven (35%) patients had AF recurrences, and they had a greater %FAP area after the PV isolation than those without (32.8 [22.1, 37.3] versus 13.8 [10.9, 19.9]%; P = 0.0049). A %FAP area after the PV isolation of > 20% was significantly associated with an AF recurrence (odds ratio 20.0, 95% confidence interval 2.26470.34; P = 0.018). No significant difference was found between the patients with and without AF recurrence in the reduction rate of anatomic sites of GPs with a vagal reflex induced by the HFS.A more marked reduction in the FAP area by the PV isolation was significantly associated with a better outcome in patients with persistent AF.

Objectives: This study aimed to investigate the anatomical characteristics complicating cavotricuspid isthmus (CTI) ablation and the effectiveness of various procedural strategies., Methods and Results: This study included 446 consecutive patients (362 males; mean age 60.5 ± 10.4 years) in whom CTI ablation was performed. A total of 80 consecutive patients were evaluated in a preliminary study. The anatomy of the CTI was evaluated by multidetector row-computed tomography (MDCT) prior to the procedure. A multivariate logistic regression analysis revealed that the angle and mean wall thickness of the CTI, a concave CTI morphology, and a prominent Eustachian ridge, were associated with a difficult CTI ablation (P < 0.01). In the main study, 366 consecutive patients were divided into 2 groups: a modulation group (catheter inversion technique for a concave aspect, prominent Eustachian ridge, and steep angle of the CTI or increased output for a thicker CTI) and nonmodulation group (conventional strategy). The duration and total amount of radiofrequency energy delivered were significantly shorter and smaller in the modulation group than those in the nonmodulation group (162.2 ± 153.5 vs 222.7 ± 191.9 seconds, P < 0.01, and 16,962.4 ± 11,545.6 vs 24,908.5 ± 22,804.2 J, P < 0.01, respectively). The recurrence rate of type 1 atrial flutter after the CTI ablation in the nonmodulation group was significantly higher than that in the modulation group (6.3 vs 1.7%, P = 0.02)., Conclusion: Changing the procedural strategies by adaptating them to the anatomical characteristics improved the outcomes of the CTI ablation.

Background: Inappropriate shocks resulting from atrial tachyarrhythmias are highly problematic for patients with an implantable cardioverter defibrillator (ICD). We aimed to determine the effectiveness of catheter ablation of atrial fibrillation (AF) in preventing inappropriate shocks due to rapid AF in patients diagnosed with Brugada syndrome (BS) who were implanted with an ICD., Methods: We performed AF ablation in 5 BS patients with ICDs who experienced inappropriate shocks caused by rapid paroxysmal AF and in a BS patient scheduled to determine an indication of an ICD implantation who frequently experienced rapid AF., Results: Although 2 patients underwent a 2nd ablation procedure because of AF recurrences, 5 of the 6 patients were finally free from AF after their last procedure during a median follow-up period of 43.2 months. No further inappropriate shocks caused by rapid AF occurred after the 1st ablation session in any of the patients. A patient developed a ventricular fibrillation storm during his electrophysiological study following the ablation procedure, and then was implanted with an ICD., Conclusions: AF ablation in BS patients may be reasonable to prevent inappropriate ICD shocks resulting from rapid AF. However, ventricular extrastimuli just after the ablation had better be avoided in them., (© 2013.)

Background: Sleep-disordered breathing (SDB) frequently is induced by sedation during ablation of atrial fibrillation (AF). We tested whether or not sedative-induced SDB is associated with clinical sleep apnea syndrome (SAS)., Methods: We examined SDB observed during intra-ablation sedation with a novel portable respiratory monitor (PM), SD-101, in 140 patients undergoing AF ablation without any known SAS. A sleep study was repeated the next night of the ablation with the simultaneous use of the SD-101 and type 3 PM, APNOMONITOR V., Results: The respiratory disturbance index (RDI) during sedation (20.0±7.8 events/h) was significantly correlated with the RDI measured by the SD-101 during the night (15.8±13.7 events/h; r=0.50) and the RDI assessed by the APNOMONITOR V during the night (12.7±12.3 events/h; r=0.55). An excellent agreement was found between the RDIs simultaneously measured with the 2 PMs (intraclass correlation coefficient, 0.84), especially for an RDI of ≥30 events/h (κ statistic value, 0.82). The area under the receiver-operating characteristic curve for the RDI with the use of the SD-101 during sedation to identify the patients with an RDI of ≥30 events/h by both PMs during the night was 0.92. A left atrial diameter of >40 mm (odds ratio [OR], 4.10) and an RDI during sedation of >20 events/h (OR, 17.75) were independently associated with having an RDI of ≥30 events/h with both PMs during the night., Conclusions: Frequent episodes of sedative-induced SDB may have a diagnostic value for SAS in patients with AF., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Background: Myocardial thickness is particularly thick at the ridge between the left pulmonary vein (PV) and the left atrial appendage (LAA) by dissection. We investigated whether atrial fibrillation (AF) ablation outcome was influenced by altering ablation strategies according to the thickness of the PV-LAA ridge using preprocedural multidetector computed tomography (MDCT)., Methods and Results: Patients with AF scheduled for extensive encircling circumferential pulmonary vein isolation (EEPVI) (110 patients) were divided into 2 groups. In the nonmodulation group (32 patients), EEPVI lines were created using a 3.5-mm tip irrigated catheter at a maximum power of 30 W for 20-30 s at each site. In the modulation group (78 patients), ablation was extended (40-60 s) at the PV-LAA ridge if its thickness was >4.0 mm on MDCT examination. Extended ablation at the PV-LAA ridge was noted in 37 patients in the modulation group. During 25±9 months of follow-up, recurrence was significantly less in the modulation group than in the nonmodulation group (10% vs. 28%; p=0.018). Logistic regression analysis showed that modifications in the ablation time and left atrium volume index were independent predictors of arrhythmia-free recovery after ablation., Conclusions: Recurrence following EEPVI could be reduced by modifications in the ablation time at the PV-LAA ridge., (Copyright © 2012 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.)

Background: High-frequency stimulation (HFS) of the atria induces atrial fibrillation (AF) when applied during sinus rhythm and elicits a parasympathetic response when delivered at sites where ganglionated plexi (GPs) are located. However, little is known about its impact after an electrophysiological study., Objective: To evaluate the impact of HFS on the short-term and long-term outcomes after the ablation of persistent AF., Methods: Thirty consecutive patients with persistent or long-standing persistent AF were randomly assigned to either receive HFS of the left atrium (n = 15) or not (n = 15) during their electrophysiological studies. Patients receiving HFS were examined to determine whether or not a vagal response was elicited by the HFS at sites where GPs were located before and after conventional pulmonary vein isolation without any ablation targeting the GPs. Patients not receiving the HFS underwent the ablation procedure alone. The rate of recurrence of AF within 3 months of the procedure (early recurrence [ER]) and the frequency of that occurring after that period (late recurrence) were compared between the patient groups., Results: The incidence of ER occurred more frequently in patients with HFS than in those without (80% vs 40%; P = .015), whereas the occurrence of late recurrence was similar between the 2 groups (27% vs 33%; P = .73). In the HFS group, the number of GPs decreased from 3.4 ± 1.1 to 1.5 ± 0.8 after the pulmonary vein isolation (P < .0001), and the decrease was smaller in the patients experiencing ER than in those without., Conclusion: HFS increases the incidence of ER in patients with persistent AF despite a partial GP modification resulting from the pulmonary vein isolation., (Copyright © 2012 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Background: Atrioventricular (AV) conduction disturbances have often been considered as an etiology of prolonged pauses during atrial fibrillation (AF). We aimed to test whether there was a significant difference in the AV conduction properties between patients with and without clinically significant pauses who underwent ablation of longstanding persistent AF., Methods: Ninety-nine patients undergoing ablation of longstanding persistent AF were divided into three groups according to the extent of pauses documented on the ambulatory electrocardiogram during AF; patients without pauses (n = 25), with pauses of <3 s (n = 52), and with pauses of ≥3 s (n = 22). The AV conduction properties, heart rate variability, and bradycardia-related symptoms after conversion to sinus rhythm were compared across the three groups plus a control group (n = 35)., Results: Sinus conversion was achieved in all patients after ablation. No differences were found across the groups in the AV conduction properties including the AH and HV intervals, AV nodal effective refractory period, or Wenckebach point. A male gender (β = 0.32; p = 0.0016), structural heart disease (β = 0.24; p = 0.02), and the AA interval right after ablation (β = 0.35; p = 0.0014), rather than the AV conduction properties, were independent determinants of the longest normal RR interval during AF. No patients experienced any bradycardia-related symptoms after ablation., Conclusions: No AV conduction abnormalities were necessarily identified after the ablation even among the patients suspected of having an AV conduction disturbance during AF.

Background: Sinus node dysfunction (SND) occasionally coexists with long-standing atrial fibrillation (AF) but is unidentifiable during AF. We aimed to identify the predictors of underlying SND when deciding the indications for long-standing persistent AF ablation., Methods: We included 105 patients undergoing ablation of long-standing persistent AF to assess the frequency of a permanent pacemaker implantation (PMI) for SND that manifested after sinus conversion and to determine the relationship between the corrected sinus node recovery time (CSNRT) and other clinical parameters obtained before the ablation including the atrial fibrillatory cycle length (AFCL)., Results: We identified 7 patients (7%) requiring a PMI for SND after AF termination. The patients with a PMI were nearly all females (6/7) and had a significantly longer CSNRT (1197 ± 647 vs 612 ± 349 milliseconds; P = .0046) and more prolonged AFCL (179 ± 19 vs 153 ± 22 milliseconds; P = .0028) than those without. The age (r = 0.26; P = .011), female sex (r = 0.25; P = .012), hypertension (r = 0.22; P = .038), and AFCL (r = 0.4; P < .0001) were significantly correlated with the CSNRT. A stepwise multivariate linear regression analysis including these parameters revealed that the AFCL was the only independent determinant of the CSNRT (β = 0.38; P = .0012). A receiver operating characteristic curve identified an AFCL of more than 162 milliseconds as the optimal cutoff value for predicting SND requiring a PMI (area under the curve, 0.84; sensitivity, 86%; specificity, 74%; P = .0066)., Conclusions: A prolonged AFCL was significantly associated with SND. Thus, assessing the AFCL in the patients with long-standing persistent AF may be helpful for the risk stratification of underlying SND., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Aims: We aimed to determine how many electrical cardioversions (ECs) should be applied to treat repetitive persistent recurrences of atrial fibrillation (AF) following ablation of persistent AF within the early post-procedural period., Methods and Results: A total of 40 patients with >1 episode of recurrent AF in the form of persistent atrial arrhythmias within 3 months following the ablation were recruited from 108 patients who underwent ablation for persistent or long-standing persistent AF. Electrical cardioversions were applied up to six times, if necessary, to restore sinus rhythm at clinical visits at 2-week intervals until 3 months after the ablation. Fourteen (35%) ablation failures defined as recurrences of AF identified from the 3rd month after the ablation procedure were finally diagnosed during the follow-up period (14 ± 4 month). The patients with an ablation failure more frequently required ECs than those without (3.7 ± 0.3 vs. 1.2 ± 0.2 times; P < 0.0001). A receiver-operating characteristic curve identified a number of ECs of ≥3 as the optimal cut-off value for predicting an ablation failure (area under the curve 0.91; sensitivity, 86%, and specificity, 96%; P = 0.0007). In the multivariate logistic regression analysis, a number of ECs of ≥3 was the only independent predictor of an ablation failure (odds ratio, 11.32; 95% confidence interval, 3.83-58.22; P = 0.0019)., Conclusion: It was difficult to maintain sinus rhythm in patients with persistent AF who required several ECs for recurrences of AF within the early post-ablation period.

Purpose: We evaluated whether time-dependent procedural improvement was independently associated with reduction in atrial fibrillation (AF) recurrences or periprocedural complications in patients who underwent catheter ablation for AF at a single medium-volume center., Methods: A total of 208 consecutive patients who underwent AF ablation from June 2006 to June 2009 were enrolled. All procedures were performed by an experienced operator, and the ablation protocol, devices, and equipment remained unchanged throughout the study period. The study period was divided into quarters (1-4 Q) to include the same number of patients within each quarter. The incidence of AF recurrences or periprocedural complications requiring a prolonged hospital stay or surgical intervention was retrospectively compared across the quarters., Results: During follow-up (15 ± 3 months), we observed 26 (13%) AF recurrences (27% in 1Q, 15% in 2Q, 6% in 3Q, 2% in 4Q; 1Q vs. 3Q, p=0.0035; 1Q vs. 4Q, p=0.0003; 2Q vs. 4Q, p=0.013) and 15 (7%) periprocedural complications (12% in 1Q, 8% in 2Q, 6% in 3Q, 4% in 4Q), both of which declined progressively over time. Multiple logistic regression analysis revealed that 1Q, but not any other patient background parameters, was an independent predictor of the incidence of AF recurrence or periprocedural complications (odds ratio, 2.45; 95% confidence interval, 1.19-5.20; p=0.015)., Conclusions: The time period when the procedure was performed significantly influenced the AF ablation outcome, indicating that operators in medium-volume centers should be committed to providing gratifying outcomes particularly early in the institutional experience with AF ablation., (Copyright © 2011 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.)

Background: A diagnosis of silent paroxysmal atrial fibrillation (AF) is highly challenging due to its asymptomatic and intermittent nature. The goal of the present study was to clarify its asymptomaticity with the use of a comprehensive electrophysiological approach. Methods: We prospectively compared (a) 24‐hour Holter monitoring data, (b) invasive cardiac electrophysiological properties, (c) AF inducibility, and (d) outcome of radiofrequency catheter ablation between patients with symptomatic paroxysmal AF and those with silent paroxysmal AF, defined as transient asymptomatic AF detected by chance. Results: Patients with silent paroxysmal AF (N = 57) were more likely than patients with symptomatic paroxysmal AF (N = 282) to be male (75.4% vs 56.7%; P = .009), and to have a previous stroke (17.5% vs 6.7%; P = .008), more prolonged atrio‐His interval (114.9 ± 29.1 vs 105.5 ± 24.1 ms; P = .01), longer atrioventricular nodal effective refractory period (352.3 ± 103 vs 318.2 ± 77.2 ms; P = .007), slower Wenckebach cycle length (488.5 ± 83.9 vs 443.3 ± 74.9 ms; P < .001), and lower maximum heart rate during AF (128.7 ± 31.9 vs 143.9 ± 29.6 beats/min; P = .02). Atrial ectopy (median [interquartile range], 385 [88, 2430] vs 207 [73.8, 870.8] beats/24 h; P = .02) and pharmacological AF induction (66.7% vs 43.2%; P = .02) were more common in silent paroxysmal AF patients. There was no difference in the 1‐year freedom from AF following the ablation between the two patient groups. Conclusions: The more attenuated atrioventricular conduction properties in silent paroxysmal AF patients may explain their asymptomatic nature, and their higher likelihood of atrial arrhythmias may increase the chance to detect AF episodes. Whether or not they benefit from catheter ablation is uncertain. [ABSTRACT FROM AUTHOR]

Aims: A worldwide survey reported that the success rate of atrial fibrillation (AF) ablation was higher in high-volume centers compared with low-volume centers. We tested whether the procedure volume of each operator was associated with the outcome of AF ablation in high-volume centres.Methods and Results: We studied 471 patients with paroxysmal AF who underwent pulmonary vein (PV) isolation for the first time in three cardiovascular centers where the annual AF ablation volume was >100 procedures. We classified a total of 10 primary operators according to their operation volume on the basis of ACC/AHA/ACP CLINICAL COMPETENCE STATEMENT; high-volume operator (≥50 cases/year, N = 3) or low-volume operator (<50 cases/year, N = 7). The patients included were dichotomized according to the annual operation volume of their attending physician. The endpoints were the freedom from AF recurrence 1 year after the ablation, major complications including thromboembolisms, massive bleeding or death, and the procedural duration.Results: A complete isolation of the four PVs was achieved in 99.1%. The freedom from AF recurrence was more common in patients treated by high-volume operators than those treated by low-volume operators (165/216 [76.4%] vs. 160/255 [62.8%]; P = 0.001). A high-volume operator was the only independent predictor of the freedom from AF recurrence (hazard ratio 1.73, 95% confidence interval 1.23-2.48; P = 0.002). The patients treated by high-volume operators were less likely to have major complications (1.4% vs. 7.8%; P = 0.001), and had a shorter procedural duration (139.9 ± 25.3 vs. 149.3 ± 27.1 min; P = 0.03).Conclusions: Operator proficiency may predict the outcome after AF ablation even in high-volume centres. [ABSTRACT FROM AUTHOR]