Segmental Pulmonary Vein Isolation Research Articles

Comparison of pulsed field ablation and thermal ablation for repeat procedures after failed prior thermal ablation for atrial fibrillation

Abstract Background Procedural efficiency and long-term clinical outcome after a first pulmonary vein isolation (PVI) for atrial fibrillation (AF) with pulsed-field ablation (PFA) has recently been reported to be non-inferior compared to radiofrequency ablation (RFA) and cryoballoon ablation (CBA). Studies comparing PFA and RFA for a first redo procedure in patients with failed prior thermal PVI are lacking. Purpose We sought to compare procedural efficiency and 1-year success rate (i.e maintenance of sinus rhythm) between PFA and RFA in patients undergoing a first redo procedure due to recurrence of atrial tachyarrhythmias after a prior thermal PVI. Methods Patients with recurrences after a 90-day blanking period following an index PVI with either RFA or CBA referred for a first redo ablation were enrolled. All redo procedures were done using a 3D electro-anatomical mapping to identify PV reconnections and guide repeat PVI by either PFA or RFA. In cases of incomplete or ostial isolation, the PFA group was treated using the standard 8-applications per vein while the CLOSE protocol was used for segmental PVI completion in the RFA group. Extra-PV lesion sets were added at the discretion of the treating physician. Patients were followed with 7d-Holter ECGs 3, 6, and 12 months after reablation. Recurring arrhythmias were categorized as persistent AF, paroxysmal AF, or atrial flutter. Secondary endpoints were periprocedural complications, total ablation time, radiation time and exposure. Results A total of 220 patients (median age 67 [IQR 58-74] years, 64% male, 64% persistent AF) were enrolled and equally treated with PFA or RFA (110 in both groups). There were no statistically significant differences in the clinical characteristics at baseline. Procedure time was shorter in the PFA group (95 vs. 122 minutes, p=0.001) whereas radiation time and dose were higher in the PFA group (17.0 vs. 6.4 minutes, p=<0.001 and 4.9 vs. 2.2 Gycm2, p=<0.001). Additional posterior wall ablation (PFA) or roof line (RFA) was performed predominantly in the PFA group (61 patients, 55.5 %) and in 5 patients (4.5 %) in the RFA group (p=0.001). Major complications occurred in 3 patients in the PFA group and in 1 patient in the RFA group (see Picture 2). Freedom from arrhythmia in Kaplan-Meier analysis 12 months after the reablation was 61% (CI 50-74%) in the PFA group and 59% (CI 49-71%; log-rank test p=0.81). No differences in outcomes were observed in the pooled group between paroxysmal AF (60%, CI: 50-72%) and persistent AF (61%, CI: 51-73%, p=0.64). Recurrence of organized atrial tachycardia was more common in the PFA group (p=0.018) Conclusion In patients undergoing a first redo procedure after a first round of thermal PVI and with recurrence of atrial tachyarrhythmia, PFA for reablation resulted in shorter procedure times compared to RFA despite more frequent posterior wall ablation. Long-term arrhythmia-free survival after the redo procedure was similar in both groups.Kaplan-Meier analysis of redo proceduresProcedure and outcome data

Changes in Heart Rate Variability Parameters Following Radiofrequency Ablation in Patients with Atrial Fibrillation: A Systematic Review and Meta-Analysis.

Radiofrequency (RF) ablation is a prevalent treatment for atrial fibrillation (AF), targeting triggers within the pulmonary vein (PV) for elimination. This study evaluated heart rate variability (HRV) parameter changes at three intervals post-RF ablation: short-term (immediately to 1 month), medium-term (1 to 6 months), and long-term (6 months to 1 year). We compared two ablation techniques: circumferential PV isolation (CPVI) and segmental PV isolation (SPVI). A thorough search of databases, including PubMed, Embase, Scopus, Web of Science, and Cochrane, in 2022 yielded 835 pertinent studies. After inclusion criteria were applied, 22 studies were analyzed. Results showed a marked decline in HRV parameters post-AF ablation, with LF/HF as an exception. These reductions persisted in short- and long-term evaluations up to a year post-procedure. Subgroup analysis revealed significant HRV declines, with distinct LF/HF values post-SPVI. This meta-analysis suggests the potential of decreased HRV as an indicator of autonomic denervation, necessitating further exploration to optimize therapeutic strategies and enhance patient outcomes.

Comparison of Long-Term Clinical Outcomes Between Segmental and Circumferential Pulmonary Vein Isolation in Patients Undergoing Repeat Atrial Fibrillation Ablation.

Circumferential pulmonary vein isolation (CPVI) has supplanted segmental PVI (SPVI) as standard procedure for atrial fibrillation (AF). However, there is limited evidence examining the efficacy of these strategies in redo ablations. In this study, we investigated the difference in recurrence rates between SPVI and CPVI in redo ablations for PV reconnection.Methods and Results: This study retrospectively enrolled 543 patients who had undergone AF ablation between 2015 and 2017. Among them, 167 patients (30.8%, including 128 male patients and 100 patients with paroxysmal AF) underwent redo ablation for recurrent AF. Excluding 26 patients without PV reconnection, 141 patients [90 patients of SPVI (Group 1) and 51 patients of CPVI (Group 2)] were included. The AF-free survival rates were 53.3% and 56.9% in Group 1 and Group 2, respectively (P=0.700). The atrial flutter (AFL)-free survival rates were 90% and 100% in Group 1 and Group 2, respectively (P=0.036). The ablation time was similar between groups, and there no major complications were observed. For redo AF ablation procedures, SPVI and CPVI showed similar outcomes, except for a higher AFL recurrence rate for SPVI after long-term follow-up (>2 years). This may be due to a higher probability of residual PV gaps causing reentrant AFL.

Intraluminal Esophageal Temperature Monitoring Using the Circa S-Cath™ Temperature Probe to Guide Left Atrial Ablation in Patients with Atrial Fibrillation.

Radiofrequency catheter ablation is a common treatment for atrial fibrillation (AF), during which thermal esophageal injury may rarely occur and lead to an atrio-esophageal fistula. Therefore, we studied the utility of the Circa S-Cath™ multi-sensor luminal esophageal temperature (LET) probe to prevent esophageal thermal injury. Thirty-six patients, enrolled prospectively, underwent circumferential or segmental pulmonary vein isolation for treatment of AF. A maximum ablation electrode temperature of 42ºC was programmed for automatic power delivery cutoff. In addition, energy delivery was manually discontinued when the maximum LET on any sensor of the probe rose abruptly (i.e. ˃0.2ºC) or exceeded 39º C. Esophagoscopy was performed immediately after ablation in 18 patients (with the temperature probe still in place) and at approximately 24 hours after ablation in 18 patients. Esophageal lesions were classified as likely traumatic or thermally related. Of the 36 patients enrolled in the study, 21 had persistent and 15 had paroxysmal AF, average LVEF 57±16% and CHA2DS2VASc score 1.6±1.2 (range 0-4). Average maximum LET was 37.8±1.4ºC, power delivery 31.1±8 watts and ablation electrode temperature 36.4±4.1ºC. Average maximum contact force was 44.5±20.5 grams where measured. Only 1 patient (<3%) had an esophageal lesion that could potentially represent thermal injury and 4 patients (11.1%) had minor traumatic mechanical injury. LET guided titration of power and duration of energy application, using an insulated multi-sensor esophageal temperature probe, is associated with a low risk of esophageal thermal injury during AF ablation. In only rare cases, LET monitoring resulted in the need to manipulate the esophagus to avoid unacceptable temperature rises, that could not be achieved by adjustment of power and duration of energy application.

Intermediate term outcome after electrogram guided segmental ostial pulmonary vein isolation using an 8 mm tip catheter for paroxysmal atrial fibrillation

IntroductionPulmonary vein isolation (PVI) is the most widely used procedure for ablation in patients with paroxysmal atrial fibrillation (AF). Not withstanding recent advancements in this field, including sophisticated three-dimensional (3D) based imaging and advanced ablation catheters with contact force technology, many patients and healthcare systems in developing countries will not afford such an expensive therapeutic procedure. There are no data from India analyzing the efficacy of PVI for PAF using conventional mapping and ablation. In this article, we have summarized the intermediate term outcome following PVI in patients with PAF using electrogram-based mapping and a 8 mm tip ablation catheter. MethodA total of 42 consecutive patients who underwent PVI for symptomatic PAF not controlled with at least one antiarrhythmic drug were studied in a tertiary care institute from March 2011 to June 2018. Patients with rheumatic AF were excluded. The pulmonary vein (PV) anatomy was assessed by pulmonary angiography during the ablation procedure. Using conventional electrophysiologic mapping, a variable curve Lasso catheter placed in the PVs was used to guide the earliest site of breakthrough. The segmental ostial PVI was performed using a 8 mm tip radiofrequency (RF) ablation catheter. Elimination of all PV ostial potentials and complete entrance block into the PV were considered indicative of complete electrical isolation. Follow-up visits were scheduled at one, three, and six months after the procedure, and every six months thereafter. History, symptom review, clinical examination, and 12-lead ECG were performed at each follow-up. ResultsAt pre-discharge, 34 patients (81%) were in sinus rhythm, while eight patients (19%) continued to have atrial fibrillation. The age of the study population was 51.5 ± 11.7 yrs. The mean follow-up duration was 44 ± 21 months (range 6–84 months). The number of PVs isolated included one (five patients, 11.9%), two (20 patients, 47.6%), three (12 patients, 28.6%), and four (five patients, 11.9%). In 42 patients, a total of 101 PVs were isolated. The right superior PV (RSPV) was isolated in 37 patients, the left superior PV (LSPV) was isolated in 39 patients, the left inferior PV (LIPV) was isolated in 14 patients, and the right inferior PV (RIPV) was isolated in six patients. The procedure duration was 125 ± 29 min and the fluoroscopy time was 47 ± 13 min. The number of patients who remained in sinus rhythm at 1, 6, 12, and 24 months were 34 (81%), 32 (76%), 30 (71%), and 26 (62%), respectively. Two patients of these underwent repeat PVI, which was successful, and they had freedom from AF episodes. Complications were rare. One patient had a minor pericardial effusion, and one patient had transient sinus pauses, which were conservatively managed. ConclusionConventional RF ablation using PV potential-based mapping and ablation with 8 mm tip catheters is safe for patients with PAF. The intermediate term outcome is satisfactory and cost-effective in our setting with limited resources.

Ten-year ablation outcomes of patients with paroxysmal atrial fibrillation undergoing pulmonary vein isolation

Pulmonary vein isolation (PVI) is commonly performed in patients with drug-refractory symptomatic paroxysmal atrial fibrillation (PAF). However, the very long-term follow-up result is limited. We aimed to investigate 10-year ablation outcomes in patients with PAF and long-term follow-up results after PVI. This study retrospectively enrolled 176 (131 men, mean age 51.2 ± 12.1 years) patients with drug-refractory symptomatic PAF who underwent electroanatomic-guided PVI. Ten-year follow-up was completed using medical records or telephonic interviews. Procedural characteristics at index procedures and long-term clinical outcomes were investigated. After a mean follow-up period of 130.0 ± 10.8 months, sinus rhythm was achieved in 102 (58%) patients after a single procedure (including 14 (8%) patients on antiarrhythmic medications) and in 88% patients after multiple procedures (including 17 (10%) patients on antiarrhythmic medications). Left atrial diameter (odds ratio 1.067; 95% confidence interval 1.009-1.127; P = .023) was the predictor of recurrent atrial tachyarrhythmia after a single ablation procedure. The single-procedure recurrence-free rates were similar between circumferential PVI and segmental PVI (59% and 50%; log-rank, P= .251). The recurrence patterns of both groups regarding the role of non-pulmonary vein and pulmonary vein triggers were similar. The single-procedure long-term efficacy was modest, with freedom from atrial fibrillation at 10 years being 58%. Those who had enlarged left atrial diameters have more atrial tachyarrhythmia recurrences. Ten-year single-procedure outcomes of the effects of circumferential PVI and segmental PVI in patients with PAF were similar.

Changes in P-wave morphology after pulmonary vein isolation: insights from computer simulations.

Apparently conflicting clinical measurements of P-wave duration (PWD) pre- vs. post-ablation have been reported. To assist the interpretation of these clinical data, we used a computer model of the atria and torso to simulate P waves before and after pulmonary vein (PV) isolation. Twenty ablation patterns were designed (segmental or ipsilateral ablation; five distances to PV sleeves; addition of a roof line or not). Possible PV reconnections were introduced as gaps in the ablation lines. PWD and area were measured during sinus rhythm in vectorcardiogram (VCG) magnitude signals and on the 16-lead ECG before and after ablation, and after PV reconnection. After PV isolation, biatrial activation time was prolonged by 0-5 ms without and by 48±5 ms with roof line. Yet PWD was shortened in lead V3 and V4 by up to 15 ms. The effect of ablation on P-wave morphology was stronger when larger PV areas were isolated. Segmental and ipsilateral PV isolation led to concordant results. P-wave area increased in V1 and decreased in V6. Changes in PWD and area on the VCG were sensitive to the threshold used for detecting the end of the P wave. The occurrence of PV reconnection was best identified on leads V3, V4, and V9. PV isolation and reconnection induced measurable changes on the 16-lead ECG that might be used to improve patient follow-up after ablation.

Comparative Effectiveness of Wide Antral Versus Ostial Pulmonary Vein Isolation

For the past decade, electric pulmonary vein isolation (PVI) has become a procedure implemented worldwide for the treatment of atrial fibrillation. Currently, 2 main approaches are used for PVI: ostial isolation of the PVs and wide antral PVI. The aims of this systematic review are to evaluate the relative merits of each technique with a pooled comparative analysis of efficacy and complications. Studies were identified by searching electronic databases for studies on ostial versus antral PVI. Information was extracted from each included trial. Odds ratio was the primary measure of treatment effect or side effects. The proportion of patients with recurrences of atrial fibrillation or other atrial tachyarrhythmias was evaluated at the end of the follow-up periods in 12 trials, including 1183 patients. The recurrence rate of total supraventricular arrhythmias was significantly lower in wide antral than in segmental PVI group (odds ratio, 0.42; 95% confidence interval, 0.32-0.56; P<0.00001). Atrial fibrillation recurrence was significantly lower in the wide antral group (odds ratio, 0.33; 95% confidence interval, 0.24-0.46; P<0,00001). A trend toward a higher incidence of left atrial tachycardia occurrence in the wide antral circumferential ablation group was detected, which did not reach statistical significance (odds ratio, 1.53; 95% confidence interval, 0.88-2.69; P=0.13). Our primary finding is that PVI performed with a wide antral approach is more effective than ostial PVI in achieving freedom from total atrial tachyarrhythmia recurrence at long-term follow-up.

Superiorly directed atrial ectopy from the left inferior pulmonary vein

P wave morphology is often useful in planning and prognosticating invasive electrophysiology testing with an aim at ablation. It is generally believed that atrial ectopy of a pulmonary vein site of origin will be inferiorly directed. We report the case of superiorly directed P waves originating from the left inferior pulmonary vein, likely the result of a prior pulmonary vein isolation procedure. As demonstrated by our case, standard algorithms to identify the site of origin of atrial ectopy should be used with caution in patients with prior ablative procedures.

Catheter Ablation for Persistent Atrial Fibrillation

A new era of atrial fibrillation (AF) treatment began in 1997–1998 with the discovery that triggers within the pulmonary veins initiate AF and reports that elimination of these triggers is successful in treating AF in its paroxysmal form.1–3 However, in patients with persistent AF, the success rate of exclusive pulmonary vein isolation is substantially lower.4,5 To improve the outcome of persistent AF ablation, different ablation strategies have been explored, but to date the optimal strategy has not been defined. Although some groups argue that limited ablation, including pulmonary vein isolation and, if present, ablation of nonpulmonary vein triggers, is sufficient for persistent AF ablation, other groups, including ours, favor more extensive, substrate-based ablation in addition to pulmonary vein isolation. In this review, we will discuss the rationale for a substrate-based ablation strategy to treat persistent AF and show why elimination of triggers is not sufficient in most patients with persistent AF. Response by Roten et al on p 1232 In a simple model, an electric impulse in AF can form because of abnormalities in impulse generation (triggers) or can result from abnormal impulse propagation (reentry). By a strict definition, a trigger is a focal source of new impulse generation. The mechanism by which a new impulse can form is either abnormal automaticity or triggered activity. Trigger-ablation protocols target these sources of new impulse generation. Abnormal impulse propagation, on the other hand, depends on altered substrate properties causing nonuniform or slowed conduction. This in turn causes multiple forms of wave reentry thought to be responsible for AF perpetuation: random reentry (multiple wavelets), macro- and microreentry, or functional reentry (rotors). Substrate-based ablation strategies aim to abate abnormal impulse propagation and interrupt any form of atrial reentry. Triggers of paroxysmal AF are mainly located in the pulmonary …

Fully equipped to defeat the pulmonary vein potentials: on the quest for sinus rhythm

This editorial refers to ‘Pulmonary vein isolation with radiofrequency ablation followed by cryotherapy: a novel strategy to improve clinical outcomes following catheter ablation of paroxysmal atrial fibrillation’ by M. H. Tayebjee et al. , on page 1250. Since its inception more than a decade ago, catheter ablation has dramatically changed our therapeutical approach to atrial fibrillation (AF). The irruption of catheter ablation occurred through the recognition of the pulmonary veins (PVs) as main triggers initiating paroxysmal AF.1 Initial ablation strategies aimed at suppression of these focal triggers. However, radiofrequency (RF) lesions placed inside the veins produced PV stenosis,2 so that ablation had to move from the veins to its antrum. Segmental PV isolation was based on this principle, and targeted only preferential connections between the antrum and the PV at its ostium. This yielded quite good results in paroxysmal AF, but produced much more modest outcome in patients with persistent forms of AF. In circumferential antral PV isolation ablation lesions are extended to encompass the left atrial PV mouth. Due to its complex histological structure, the PV antrum itself plays an important role not only in initiation, …

AF Ablation II

AF Ablation II

Catheter Ablation of Atrial Fibrillation

Atrial fibrillation (AF) is an arrhythmia associated with increased morbidity and mortality. Since the first report of catheter ablation curing AF, numerous techniques have evolved, from linear ablation to segmental pulmonary vein (PV) isolation, to extensive encircling PV isolation, to left atrial (LA) linear ablation, to ablation of complex fragmented atrial electrograms (CFAEs) and ablation of ganglionated plexi. A new approach for complete isolation of the posterior LA, including all PVs, is box isolation. PV isolation is associated with a high clinical success rate in paroxysmal AF. However, in persistent AF or longstanding persistent AF, PV isolation only may not be sufficient, so additional ablation at sites with CFAEs is needed to improve the clinical outcome. A hybrid approach of combining PV isolation plus CFAE ablation is highly effective in the majority of patients with persistent AF or longstanding persistent AF. Thus, AF ablation is an effective and established treatment for AF that offers an excellent chance of a lasting cure. It is about time that AF ablation became a first-line therapy for selected patients with AF.

Time course of markers of tissue repair after ablation of atrial fibrillation and their relation to left atrial structural changes and clinical ablation outcome

BackgroundRadiofrequency ablation of atrial fibrillation (AF) creates left atrial (LA) tissue damage with a subsequent healing process. We sought to prospectively assess the time course of biomarkers of tissue repair after ablation and to evaluate their association with clinical variables. Methods30 consecutive patients (57.9±1.7yrs, 63% males) with paroxysmal AF underwent a CARTO-guided LA circumferential ablation, Lasso-guided segmental pulmonary vein isolation and ablation of complex fractionated atrial electrograms. Matrix metalloproteinase-9 (MMP-9) and transforming growth factor-β1 (TGF-β1), both key regulators of tissue repair, and the aminoterminal propeptide of type III procollagen (PIIINP), reflecting collagen synthesis, were determined in blood samples before and 6h, 1, 2, 7, 30, 90 and 180days post-ablation. ResultsAll markers showed a significant ablation-induced up-regulation (MMP-9: 1.8±0.1-fold, TGF-β1: 2.4±0.4-fold, PIIINP: 1.3±0.1-fold). MMP-9 was significantly up-regulated until day 90, TGF-β1 only on day 2. PIIINP increased from day 2 to 7. The area under the curve (AUC) of MMP-9 and TGF-β1 correlated with the ablation-induced reduction of LA volume (both p<0.05). The AUC of MMP-9 was additionally associated with the amount of radiofrequency energy delivered during ablation (p<0.05). At 12months of follow-up 57% of patients were free of AF off antiarrhythmic drugs. The AUC of PIIINP independently predicted recurrent AF (p<0.05). ConclusionsMarkers of healing showed a significant up-regulation after AF ablation detectable for up to 90days. A more pronounced up-regulation of MMP-9 or TGF-β1 is associated with a greater reduction of LA size. High PIIINP levels after ablation predict a poor ablation outcome.

Circumferential Pulmonary Vein Ablation With Additional Linear Ablation Results in an Increased Incidence of Left Atrial Flutter Compared With Segmental Pulmonary Vein Isolation as an Initial Approach to Ablation of Paroxysmal Atrial Fibrillation

There has been growing concern that linear ablation is associated with an increased risk of iatrogenic arrhythmias in patients undergoing ablation for atrial fibrillation (AF). Therefore, we compared circumferential pulmonary vein ablation plus left atrial linear ablation (CPVA+LALA) with segmental pulmonary vein isolation (PVI)in patients with paroxysmal AF. Sixty-six consecutive patients with paroxysmal AF were prospectively randomly assigned to receive PVI versus CPVA+LALA (consisting of encircling lesions around the pulmonary veins), a roof line, and a mitral isthmus line with documentation of bidirectional mitral isthmus block. All patients were seen at 1, 3, 6, and every 12 months after ablation, with 14-day continuous ECG monitoring every 6 months. At 16.4+/-6.3 months after 1 ablation procedure, 19 patients (58%) remained free of atrial arrhythmias after PVI versus 17 patients (51%) after CPVA+LALA (P=0.62). After PVI, 14 patients had recurrent paroxysmal AF, whereas after CPVA+LALA, 8 patients had recurrent AF, 6 had atypical left atrial flutter (LAFL), and 2 had both AF and LAFL (P=0.32 between PVI versus CPVA+LALA for AF but P=0.002 for LAFL). Twenty-eight patients (85%) remained arrhythmia-free after 1.3+/-0.5 PVI procedures versus 28 patients (85%) after 1.4+/-0.6 CPVA+LALA procedures (P=NS). Fluoroscopy time was longer after CPVA+LALA versus PVI (91 versus 73 minutes, P=0.04). As an initial ablation approach in patients with paroxysmal AF, more LAFL occurred after CPVA+LALA and fluoroscopy times were longer compared with segmental PVI.

Long-Term Outcome After Successful Catheter Ablation of Atrial Fibrillation

Pulmonary vein isolation (PVI) is increasingly used for treatment of atrial fibrillation (AF), but few reports exist regarding long-term success. We determined 5-year outcomes of PVI among patients with freedom from AF off antiarrhythmic drugs (AAD) for 1 year after PVI. Consecutive patients with paroxysmal or persistent AF who underwent PVI at the University of Pennsylvania from 2000 to 2003 and were free from AF 1 year after ablation were included. Proximal isolation of PVs and non-PV triggers of AF was performed. Long-term ablation success, defined as freedom from AF off AAD after a single ablation procedure, was determined. All patients had transtelephonic monitoring at 3 to 6 months and 12 months and at least yearly contact thereafter. One hundred twenty-three patients were free of AF without AAD at 1 year. AF freedom off AAD was 85% at 3 years and 71% at 5 years, with an approximate 7% per year late recurrence rate after the first year. Patients with recurrent AF >or=5 years after index PVI were older, had larger left atrial size, more AF triggers and more likely had persistent AF. In multivariate analysis, persistent AF (odds ratio, 2.8; 95% confidence interval, 1.4 to 5.7, P=0.005) and age (odds ratio, 1.1; 95% confidence interval, 1.0 to 1.1, P=0.036) independently predicted long-term AF recurrence. Among patients with paroxysmal or persistent AF and AF freedom 1 year after segmental PVI, the majority (71%) remained free of AF for up to 5 years, with an approximate late recurrence rate of 7% per year. Continued vigilance for recurrent AF after PV isolation is warranted, particularly in patients with persistent AF.

Hybrid Therapy of Radiofrequency Catheter Ablation and Percutaneous Transvenous Mitral Commissurotomy in Patients With Atrial Fibrillation and Mitral Stenosis

The rhythm control of atrial fibrillation (AF) associated with mitral stenosis (MS) is often difficult using antiarrhythmic drugs (AADs), even after a percutaneous transvenous mitral commissurotomy (PTMC). Few studies have examined the efficacy and safety of simultaneously performing radiofrequency catheter ablation (RFCA) and a PTMC in patients with MS and AF. Twenty consecutive patients with drug-resistant AF and rheumatic MS underwent RFCA combined with a PTMC (n = 10; persistent AF-8, long-lasting [>1 year] persistent AF-2; RFCA group) or transthoracic direct cardioversion (DC) following a PTMC (n = 10; persistent AF-7, long-lasting persistent AF-3; DC group). In all patients, the mitral valve morphology was amenable to a PTMC, and more than 2 AADs had been ineffective in maintaining sinus rhythm (SR). In the RFCA group, a segmental pulmonary vein isolation (PVI) was performed in the initial 5 patients, and an extensive PVI was performed in the remaining 5. During a mean follow-up period of 4.0 +/- 2.7 years, 8 patients (80%) in the RFCA group were maintained in SR, as compared to 1 (10%) in the DC group (hazard ratio, 0.16; 95% confidence interval, 0.03 to 0.75; P = 0.008 by the log-rank test). The prevalence of the concomitant use of class I and/or class III AADs was comparable between the 2 groups (P = 0.70). No complications occurred during the procedure or follow-up period in either group. The hybrid therapy using RFCA and a PTMC was safe and feasible, and significantly improved the AF free survival rate compared to DC following a PTMC.

The difference in autonomic denervation and its effect on atrial fibrillation recurrence between the standard segmental and circumferential pulmonary vein isolation techniques

This study examined the difference in autonomic modification (AM) and its effect on paroxysmal atrial fibrillation (PAF) recurrence between segmental pulmonary vein isolation (S-PVI) and circumferential PVI (C-PVI). Successful S-PVI or C-PVI with a basket catheter was achieved in 120 consecutive PAF patients. Serial 24 Holter-recordings were obtained before, immediately, and 1, 3, 6, 12 months after the PVI to analyse the heart rate variability (HRV). Nineteen patients were excluded from analysis because of additional ablation for recurrent PAF after successful PVI. Among the residual 101 patients, 33 had PAF recurrences (S-PVI = 44.0%, C-PVI = 21.6%) at 1 year of follow-up. The root mean square of successive differences and high-frequency power reflecting parasympathetic nervous activity were significantly lower in patients with and without PAF recurrences after C-PVI and patients without PAF recurrences after S-PVI than patients with PAF recurrences after S-PVI (P < 0.005-0.0001). However, there were no significant differences in any HRV parameters in the immediate aftermath of PVI among the patients without PAF recurrences after S-PVI and those with and without PAF recurrences after C-PVI. Although additional radiofrequency ablation for AM may be recommended after S-PVI to reduce PAF recurrences, it should be carefully determined after C-PVI.

Paroxysmales und persistierendes Vorhofflimmern: Neue Therapiekonzepte der Pulmonalvenen-Isolation

Interventional therapy of atrial fibrillation (AF) is often associated with long examination- and fluoroscopy times. The use of mapping catheters in addition to the ablation catheter requires multiple transseptal sheets for left atrial access. The HDMA was introduced in 2007 for the the segmental and circumferentil ablation of paroxysmal atrial fibrillation. In small experimental study groups the new catheter system was validated for its electrophysiological properties. The purpose of this prospective study was to evaluate feasibility and safety of pulmonary vein (PV) isolation using the High Density Mesh Ablator (HDMA), a novel single, expandable electrode catheter for both mapping and radiofrequency (RF) delivery at the left atrium/PV junctions. 40 patients with highly symptomatic paroxysmal AF (PAF, 23/57,5 %) and persistent AF (CAF, 17/42,5 %) were studied. PV isolation via the HDMA was performed using a customized pulsed RF energy delivery program (target temperature 55 - 60 degrees, power 70 - 100 Watt, 600 - 1000 seconds RF application time/PV). All 158 PV in 40 patients could be mapped and ablated by the HDMA. Segmental PV isolation was achieved with a mean of 3,75 +/- 1,9 RF applications for a mean of 715 +/- 375 sec. Entrance conduction block was obtained in 93,5 % of all PV. Mean total procedure and fluoroscopy time was 152 +/- 34 min and 29 +/- 10 min respectively. None of the patients experienced severe complications. After 3 month 78 % of the patients with PAF and 41 % with CAF respectively were free of AF. In this first study of PV isolation using the HDMA, our findings suggest that this method is feasible, and yields good primary success rates. Due to single transseptal access the HDMA simplifies the complex procedure of AF ablation, favorably impacting procedure and fluoroscopy times.

Catheter ablation vs. amiodarone plus losartan for prevention of atrial fibrillation recurrence in patients with paroxysmal atrial fibrillation

Although amiodarone plus angiotensin II receptor blockers (ARBs) and catheter ablation may improve sinus rhythm maintenance of paroxysmal atrial fibrillation (AF), their clinical efficacies have not been compared. This prospective cohort study was designed to compare clinical efficacy of catheter ablation and amiodarone plus losartan on sinus rhythm maintenance in patients with paroxysmal AF. A total of 240 patients with paroxysmal AF were assigned to four groups. CPVA group (n = 60) was treated with circumferential pulmonary vein ablation (CPVA), SPVI group (n = 60) with segmental pulmonary vein isolation, AMIO group (n = 60) with amiodarone and AMIO + LO group (n = 60) with amiodarone plus losartan. The endpoint was documented recurrence of AF > 30 s by Holter or conventional 12-lead ECG in the 1-year follow-up period. During 12 months of follow-up, the primary end point was reached in 28 patients in CPVA group, 14 patients in SPVI group, 25 patients in AMIO group and 13 patients in AMIO + LO group, respectively. The sinus rhythm in SPVI and AMIO + LO group were significant higher than that in CPVA and AMIO group (P < 0.01 and 0.025), and no difference between CPVA and AMIO group. The maintenance rate of sinus rhythm in SPVI group was similar to that in AMIO + LO group. This study demonstrates that segmental pulmonary vein isolation in preventing AF recurrence is similar to amiodarone plus losartan, but it is superior to CPVA and amiodarone alone in patients with paroxysmal AF. Larger multicentre studies are needed to confirm its long-term outcomes.