Shin-ichi Tanigawa

Repeated provocation of time- and ATP-induced early pulmonary vein reconnections after pulmonary vein isolation: eliminating paroxysmal atrial fibrillation in a single procedure.

Background— Recurrence of atrial fibrillation (AF) after successful pulmonary vein isolation (PVI) occurs mainly due to the reconnection of the once isolated PV. Although provocation and elimination of the early pulmonary vein reconnection (EPVR) soon after PVI has been widely performed to improve the outcome, AF recurrence due to subsequent PV reconnections still occurs. In this study, we repeatedly provoked and eliminated the EPVR to determine the appropriate procedural end point. Methods and Results— Seventy-five patients with paroxysmal AF underwent PVI. EPVR was provoked by both time and ATP induction every 30 minutes until 90 minutes after the individual isolation of all PVs. The number of reconnected atrio-PV gaps were evaluated and reablated at each provocation step. Although both time- and ATP-dependent EPVR was induced most frequently at 30 minutes after PVI (75 and 76 gaps, respectively), the prevalence of induced EPVR at 60 minutes was still high (64 and 36 gaps induced by time and ATP, respectively). Only a small number of EPVR appeared at 90 minutes after the elimination of all EPVR by 60 minutes (8 gaps, P<0.01). During the mean follow-up period of 370 days, 92% of cases were free from AF without antiarrhythmic drugs. Conclusions— Provocation and elimination of time- and ATP-induced EPVR not only at 30 minutes but also at 60 minutes is recommended after PVI to improve its efficacy.Background— Recurrence of atrial fibrillation (AF) after successful pulmonary vein isolation (PVI) occurs mainly due to the reconnection of the once isolated PV. Although provocation and elimination of the early pulmonary vein reconnection (EPVR) soon after PVI has been widely performed to improve the outcome, AF recurrence due to subsequent PV reconnections still occurs. In this study, we repeatedly provoked and eliminated the EPVR to determine the appropriate procedural end point.nnMethods and Results— Seventy-five patients with paroxysmal AF underwent PVI. EPVR was provoked by both time and ATP induction every 30 minutes until 90 minutes after the individual isolation of all PVs. The number of reconnected atrio-PV gaps were evaluated and reablated at each provocation step. Although both time- and ATP-dependent EPVR was induced most frequently at 30 minutes after PVI (75 and 76 gaps, respectively), the prevalence of induced EPVR at 60 minutes was still high (64 and 36 gaps induced by time and ATP, respectively). Only a small number of EPVR appeared at 90 minutes after the elimination of all EPVR by 60 minutes (8 gaps, P <0.01). During the mean follow-up period of 370 days, 92% of cases were free from AF without antiarrhythmic drugs.nnConclusions— Provocation and elimination of time- and ATP-induced EPVR not only at 30 minutes but also at 60 minutes is recommended after PVI to improve its efficacy.

Completion of mitral isthmus ablation using a steerable sheath: prospective randomized comparison with a nonsteerable sheath.

Completion of Mitral Isthmus Ablation. Background: Although mitral isthmus (MI) ablation in atrial fibrillation (AF) patients has been shown to be an effective ablative strategy, the establishment of the bidirectional conduction block of the MI is technically challenging. We investigated the usefulness of a steerable sheath for MI ablation in patients with persistent AF and its impact on the clinical outcome of persistent AF ablation.

Relationship between renal function and the risk of recurrent atrial fibrillation following catheter ablation

Background Although several clinical variables are associated with the recurrence of atrial fibrillation (AF) following catheter ablation, the influence of renal function remains to be determined. Objective To evaluate the association of renal function with the outcome of the paroxysmal AF ablation. Methods 224 patients underwent catheter ablation for paroxysmal AF. The relationship between the pre-procedural clinical valuables and ablation outcomes was evaluated. Results Over the course of 37.4±24.4u2005months of follow-up of catheter ablation procedures for AF (mean number of procedures 1.33±0.45), 91.1% of patients (204/224) became free from AF without antiarrhythmic drugs. The estimated glomerular filtration rate (eGFR) was lower in patients with recurrent AF than in those without recurrence (66.6±17.5 vs 78.4±16.8u2005ml/min/1.73u2005m2, p=0.003). AF recurred more frequently in patients with low eGFR (<60u2005ml/min/1.73u2005m2) than in those with high eGFR (>60u2005ml/min/1.73u2005m2; 24.3% vs 6.7%, p=0.006). Among the various clinical factors, low eGFR (p=0.02) and left atrium (LA) dilatation (p=0.002) independently predicted the clinical outcome of ablation in patients with paroxysmal AF. Conclusion Low eGFR and LA dilatation independently influence the outcome of catheter ablation for paroxysmal AF.

Comparison of the clinical outcome after pulmonary vein isolation based on the appearance of adenosine-induced dormant pulmonary vein conduction.

BACKGROUNDnThe elimination of transient pulmonary vein (PV) reconduction (dormant PV conduction) revealed by adenosine in addition to PV isolation reduced the atrial fibrillation (AF) recurrence after catheter ablation. The dormant PV conduction is induced in approximately half of the AF patients that undergo PV isolation. The present study compared the clinical outcome of AF ablation in patients whose dormant PV conduction was eliminated by additional radiofrequency applications with the outcome in patients without dormant conduction.nnnMETHODSnA total of 233 consecutive patients (206 male, 54.2 +/- 10.1 years) that underwent AF ablation were included in the present study. Dormant PV conduction was induced by the administration of adenosine triphosphate after PV isolation and was eliminated by supplemental radiofrequency application. All patients were followed up for >12 months (mean 903 days) after the first ablation.nnnRESULTSnFollowing PV isolation, dormant PV conduction was induced in 139 (59.7%) of 233 patients and was successfully eliminated in 98% (223/228) of those in the first ablation procedure. After the first procedure, 63.9% (149/233) of patients were free from AF recurrence events. The success rates of a single or final AF ablation in patients with the appearance of the dormant PV conduction were similar to those of patients without dormant conduction (P = .69 and P = .69, respectively).nnnCONCLUSIONSnDormant PV conduction was induced in over half of the patients with AF. After the elimination of adenosine triphosphate-induced reconnection, the clinical outcome of patients with the dormant PV conduction was equivalent to that of patients without conduction.

Dormant pulmonary vein conduction induced by adenosine in patients with atrial fibrillation who underwent catheter ablation

BACKGROUNDnintravenous administration of adenosine triphosphate (ATP) is used to induce transient pulmonary vein (PV) reconduction (dormant PV conduction) following PV isolation. This study investigated the detailed characteristics of dormant PV conduction in patients with atrial fibrillation (AF) who underwent catheter ablation.nnnMETHODSntwo hundred sixty consecutive patients (235 men; mean age, 54 ± 10 years) who underwent catheter ablation of their AF were included in this study. ATP was injected following PV isolation to induce dormant PV conduction, which was then eliminated by radiofrequency application.nnnRESULTSndormant PV conduction was induced by ATP in 60.4% (157/260) of the patients and in 25.3% (258/1,021) of the isolated PVs. This transient PV reconduction was more frequently observed in the left superior PV in comparison with other PVs (P < .0001). There was no significant difference in the prevalence of the dormant PV conduction among patients with paroxysmal AF, persistent AF, and long-lasting AF (62%, 66%, and 48%, respectively; P = .13). During the follow-up period, repeat AF ablation was performed in 70 patients with recurrent AF. The dormant PV conduction was less frequently induced in the repeat procedure than in the initial procedure (60.4% vs 31.4%, P < .0001).nnnCONCLUSIONSndormant PV conduction was evenly induced among AF types. The repeat PV isolation led to the decrease in incidence of the ATP-induced acute transient pharmacological PV reconduction.

The role of successful catheter ablation in patients with paroxysmal atrial fibrillation and prolonged sinus pauses: outcome during a 5-year follow-up

AIMSnAlthough patients with paroxysmal atrial fibrillation (AF) and prolonged sinus pauses [tachycardia-bradycardia syndrome (TBS)] are generally treated by permanent pacemaker, catheter ablation has been reported to be a curative therapy for TBS without pacemaker implantation. The purpose of this study was to define the potential role of successful ablation in patients with TBS.nnnMETHODS AND RESULTSnOf 280 paroxysmal AF patients undergoing ablation, 37 TBS patients with both AF and symptomatic sinus pauses (age: 62 ± 8 years; mean maximum pauses: 6 ± 2 s) were analysed. During the 5.8 ± 1.2 years (range: 5-8.7 years) follow-up, both tachyarrhythmia and bradycardia were eliminated by a single procedure in 19 of 37 (51%) patients. Repeat procedures were performed in 14 of 18 patients with tachyarrhythmia recurrence (second: 12 and third: 2 patients). During the repeat procedure, 79% (45 of 57) of previously isolated pulmonary veins (PVs) were reconnected to the left atrium. Pulmonary vein tachycardia initiating the AF was found in 46% (17 of 37) and 43% (6 of 14) of patients during the initial and second procedure, respectively. Finally, 32 (86%) patients remained free from AF after the last procedure. Three patients (8%) required pacemaker implantation, one for the gradual progression of sinus dysfunction during a period of 6.5 years and the others for recurrence of TBS 3.5 and 5.5 years after ablation, respectively.nnnCONCLUSIONnCatheter ablation can eliminate both AF and prolonged sinus pauses in the majority of TBS patients. Nevertheless, such patients should be continuously followed-up, because gradual progression of sinus node dysfunction can occur after a long period of time.

Substrate Modification by Pulmonary Vein Isolation and Left Atrial Linear Ablation in Patients with Persistent Atrial Fibrillation: Its Impact on Complex‐Fractionated Atrial Electrograms

PV and Linear Ablation for CFAEs.u2002Introduction: Linear ablations in the left atrium (LA), in addition to pulmonary vein (PV) isolation, have been demonstrated to be an effective ablation strategy in patients with persistent atrial fibrillation (PsAF). This study investigated the impact of LA linear ablation on the complex‐fractionated atrial electrograms (CFAEs) of PsAF patients.

Adenosine testing during cryoballoon ablation and radiofrequency ablation of atrial fibrillation: A propensity score–matched analysis

BACKGROUNDnThe infusion of adenosine triphosphate after radiofrequency (RF) pulmonary vein (PV) isolation (PVI), which may result in acute transient PV-atrium reconnection, can unmask dormant conduction.nnnOBJECTIVEnThe purpose of this study was to compare the incidence and characteristics of dormant conduction after cryoballoon (CB) and RF ablation of atrial fibrillation (AF).nnnMETHODSnOf 414 consecutive patients undergoing initial catheter ablation of paroxysmal AF, 246 (59%) propensity score-matched patients (123 CB-PVI and 123 RF-PVI) were included.nnnRESULTSnDormant conduction was less frequently observed in patients who underwent CB-PVI than in those who underwent RF-PVI (4.5% vs 12.8% of all PVs; P < .0001). The incidence of dormant conduction in each PV was lower in patients who underwent CB-PVI than in those who underwent RF-PVI in the left superior PV (P < .0001) and right superior PV (P = .001). The site of dormant conduction was mainly located around the bottom of both inferior PVs after CB-PVI. Multivariable analysis revealed that a longer time to the elimination of the PV potential (odds ratio 1.018; 95% confidence interval 1.001-1.036; P = .04) and the necessity of touch-up ablation (odds ratio 3.242; 95% confidence interval 2.761-7.111; P < .0001) were independently associated with the presence of dormant conduction after CB-PVI. After the elimination of dormant conduction by additional ablation, the AF-free rate was similar in patients with and without dormant conduction after both CB-PVI and RF-PVI (P = .28 and P = .73, respectively).nnnCONCLUSIONnThe results of the propensity score-matched analysis showed that dormant PV conduction was less frequent after CB ablation than after RF ablation and was not associated with ablation outcomes.

Adenosine-induced atrial tachycardia and multiple foci initiating atrial fibrillation eliminated by catheter ablation using a non-contact mapping system.

A 47-year-old male with both atrial tachycardia and atrial fibrillation underwent catheter ablation. During the procedure, rapid administration of adenosine triphosphate induced atrial tachycardia. A non-contact mapping system revealed a focal atrial tachycardia originating from the lateral right atrium, which was successfully ablated. Following the ablation of tachycardia, atrial fibrillation was induced by the injection of adenosine along with multiple extra pulmonary vein foci, which were eliminated by the application of radiofrequency under the guidance of a non-contact mapping system.

Beyond the Storm: Comparison of Clinical Factors, Arrhythmogenic Substrate, and Catheter Ablation Outcomes in Structural Heart Disease Patients With versus Those Without a History of Ventricular Tachycardia Storm

Catheter ablation can be lifesaving in ventricular tachycardia (VT) storm, but the underlying substrate in patients with storm is not well characterized. We sought to compare the clinical factors, substrate, and outcomes differences in patients with sustained monomorphic VT who present for catheter ablation with VT storm versus those with a nonstorm presentation.