Circumferential Pulmonary Vein Research Articles

Results of a survey concerning atrial fibrillation ablation strategies in Poland.

Catheter ablation is an effective treatment for patients with atrial fibrillation (AF). Despite the increasing availability of the procedure, current treatment patterns of invasive AF treatment in Poland are unknown. The aim of the study was to assess data on the contemporary approaches to AF ablation in Poland, such as: target population, patients' characteristics, ablation techniques, procedural results, and complication rates. The survey including 36 questions was conducted among 38 representatives of Polish electrophysiology centers performing AF catheter ablation to test the methods and outcomes in their laboratories. The survey was conducted among 38 out of 69 Polish electrophysiology centers performing AF ablation. There were 88 ablation laboratories in 2018 in Poland. They have performed 16 566 ablations, of which 6680 were AF ablations, according to the Polish National Health Fund data. Therefore, 3745 AF ablations analyzed in this study constituted 22.6% of all ablations and 56% of AF ablations performed in Poland in 2018.Paroxysmal AF was the most common type of AF in all surveyed centers. In 69% of the centers, the preferred method was cryoballoon ablation and in 31%, radiofrequency point‑by‑point circumferential pulmonary vein isolation. The reported complication rate was low (6.4%), with localadverse events being the most frequent. The mean reported incidence of atrial flutter or tachycardia after ablation was low (5%). Repeated procedures were performed mainly with radiofrequency ablation (89%). Procedural techniques and the type of venous access did not vary between the centers. Paroxysmal AF was the most common indication for percutaneous ablation of that arrhythmia in Polish electrophysiology laboratories. The preferred method was cryoballoon ablation.

P962Circumferential pulmonary vein ablation in combination with a linear lesion at the left atrial roof for catheter ablation of persistent atrial fibrillation (8.5-year follow-up)

Abstract Background Catheter ablation has become the first line of therapy in patients with symptomatic, recurrent, drug-refractory atrial fibrillation. Circumferential pulmonary vein ablation is still the standard approach in these patients. However, the results are not very favourable and more complex ablation strategies are the subject of current controversy. Therefore, we have evaluated the effect of an additional linear lesion at the roof of the left atrium on the long-term outcome. Methods A total of 220 patients (114 men, 106 women; mean age 69 years (SD ± 14 years)) with symptomatic persistent atrial fibrillation underwent a circumferential pulmonary vein ablation procedure in combination with an additional linear lesion at the roof of the left atrium (group A). After discharge, patients were scheduled for repeated visits at the arrhythmia clinic at 1, 3, 6, 12, 24, 36, 48, 60, 72, 84, 96 and 102 months after the ablation procedure. The long-term follow-up data was compared to 220 patients who underwent circumferential pulmonary vein ablation without an additional linear lesion at the roof of the left atrium (group B). Results The ablation procedure could be performed as planned in all patients. Fifty-one out of 220 patients (23.2 %) in group A and 53 out of 220 patients (24.1 %) in group B experienced an arrhythmia recurrence within the first 3 months after ablation requiring an electrical cardioversion. At 102-month follow-up, analysis of a 168-hour ECG recording revealed no evidence for an arrhythmia recurrence in 125/220 patients (56.8 %) in group A and in 103/220 patients (46.8 %) in group B. In 66/220 patients (30.0 %) in group A and 59/220 patients (26.8 %) in group B, only short episodes of paroxysmal atrial fibrillation were documented. In 29 patients (13.2 %) in group A, a recurrence of persistent atrial fibrillation (> 48 hours) was revealed by the long-term recordings (group B: 58 patients (26.4 %)). The lower arrhythmia recurrence rate in group A was partially due to a lower incidence of atypical atrial flutter after catheter ablation. The rate of repeat ablation procedures was significantly lower in group A than in group B. There were no major complications. Conclusions Catheter ablation of persistent atrial fibrillation comprising a circumferential pulmonary vein ablation and an additional linear lesion at the roof of the left atrium provides more favourable results than circumferential pulmonary vein ablation alone. The effect is more pronounced during long-term than during short-term follow-up.

P1375Catheter ablation of atrial fibrillation: three-dimensional transesophageal echocardiography versus magnetic resonance imaging for pulmonary vein imaging (periprocedural results and long-term follow-u

Abstract Catheter ablation has become the first line of therapy in patients with symptomatic, recurrent, drug-refractory atrial fibrillation (AF). However, it is still challenging because of the high degree of variability of the pulmonary vein (PV) anatomy. Three-dimensional transesophageal echocardiography (TEE) is a promising new technique for cardiac imaging. Therefore, we have evaluated the usefulness of 3-D TEE for analysing the left atrial anatomy prior to an ablation procedure in comparison to magnetic resonance imaging (MRI). Methods In 120 patients, 3-D TEE and cardiac MRI were performed immediately prior to an ablation procedure (paroxysmal AF: 50 patients, persistent AF: 70 patients). The image quality provided by 3-D TEE and by cardiac MRI was compared in all patients. Two different ablation strategies were used. In patients with paroxysmal AF, the cryoablation technique was used. In the other patients, a circumferential pulmonary vein ablation was performed using a three-dimensional mapping system. Results A 3-D TEE and a cardiac MRI could be performed successfully in all patients prior to the ablation procedure. Several variations of the PV anatomy could be visualized precisely by 3-D TEE and cardiac MRI (e.g. accessory PVs, common PV ostia, varying diameter of the left atrial appendage and its distance to the left superior PV). The image quality was good in the majority of patients even if AF with rapid ventricular response was present during the examination. The image quality provided by 3-D TEE was acceptable in 116/120 patients (96.7 %). The TEE findings correlated well with the PV angiographies performed using cardiac MRI. There was a good correlation with regard to the diameter of the PV ostia assessed by these two imaging techniques. All ablation procedures could be performed successfully (mean number of completely isolated PVs: 3.9 (cryo group), 4.0 (radiofrequency catheter ablation group)). At 42-month follow-up, 70.0 % of all patients were free from an arrhythmia recurrence (cryo group: 76.0 %, Carto group: 65.7 %). There were no major complications. Conclusions AF ablation procedures can be performed safely and effectively based on prior 3-D TEE imaging. The image quality was acceptable in the vast majority of patients.

P1021Low incidence of atrial tachycardia following ablation of low voltage areas in sinus rhythm for persistent atrial fibrillation

Abstract . Background: Dedicated ablation strategies for persistent atrial fibrillation (AF) have shown a limited success rate with frequent atrial tachycardia (AT) occurrence. Recent studies suggest that atrial arrhythmogenic sites are related to tissular heterogeneities and increased fibrosis can be identified as reduced bipolar voltage areas. . Purpose: Targeting low voltage areas (LVA) in addition to PVI may represent an efficient strategy for the ablation of persistent AF, and may limit the risk of AT recurrence. . Methods: We prospectively included consecutive patients with symptomatic persistent AF. The ablation strategy consisted of the following steps: circumferential pulmonary vein isolation (CPVI), Sinus rhythm restoration by electrical cardioversion, voltage map performed in sinus rhythm. Complementary RFA was guided by low voltage areas (0.2-0.4 mV). Success was defined as freedom from AF/ atrial flutter or atrial arrhythmia at 12 months or more. . Results: 101 patients (mean age: 62.5 +/- 10.4 years, men 73%) were included with persistent AF or long standing AF (7%). Procedure time was: 154 ± 25 min and fluoroscopy time: 184 ± 90 sec. Time of RFA was 44.7 +/- 12 min. Mean LA volume was 182 +/- 38 mL. LVA were found in 50 patients (49.5%). The distribution of these areas was: 30 anterior wall 29.7%), 21 septum (20.7%), 19 roof (18.8%), 5 inferior (4.9%), 11 left appendage (10.8%), 6 posterior (5.9%), 3 mitral isthmus (3%). RF ablation was realized for all LVA and homogenisation was attempt. After a single procedure at a mean FU of 12 months, 72.3% of patients were free of symptomatic AF. 27 patients had recurrence of atrial AF: 7 permanent, 15 persistent and 5 paroxysmal AF. Predictive factors of recurrence of AF were: long standing persistent AF, large left atrial volume (> 205 mL), shorts AF cycle length (< 168 ms) and reduce LEVF (< 45%). Atrial tachycardia occurred in 5 patients (4,9%). Mechanisms of AT were: typical cavo-tricuspid flutter in one patient, peri-mitral flutter in 2 patients, and atrial focal tachycardia (close to pulmonary veins) in 2 patients. . Conclusion: These results suggest that PVI with complementary RF ablation guided on low voltage areas is an efficient strategy for symptomatic persistent AF, and reduce the recurrence of AT following this ablation strategy.

P1415Wide antral circumferential pulmonary vein isolation ablation using a novel balloon cryoablation catheter

Abstract Background Pulmonary vein isolation using cryotherapy is an established treatment for the management of patients with paroxysmal atrial fibrillation. Ablation using the commercially available balloon cryocatheter has been shown to create wide antral pulmonary vein isolation. A novel balloon cryocatheter (BCC) has been designed to maintain uniform pressure and size during ablation, potentially improving contact with the antral anatomy. The extent of ablation created using the novel BCC has not previously been established. Purpose To determine the anatomical extent of pulmonary vein isolation using electroanatomical mapping when performing catheter ablation for paroxysmal atrial fibrillation using the novel BCC. Methods Nine consecutive patients underwent pre-procedure computed tomography angiography of the left atrium to quantify the chamber dimensions. An electroanatomical map was created using the cryoablation system mapping catheter and a high definition mapping system. A bipolar voltage map was obtained following ablation to determine the extent of pulmonary vein isolation ablation. A volumetric technique was used to quantify the extent of vein and posterior wall electrical isolation in addition to traditional techniques for proving entrance and exit block. Results All patients had paroxysmal atrial fibrillation, mean age 56 years, 7 (78%) male. Electrical isolation was achieved for 100% of the pulmonary veins; mean total procedure time was 109 min (+/- 26 SD), and fluoroscopy time 14.9 min (+/- 2.4 SD). The median treatment applications per vein was one (range one - four), and median treatment duration 180 sec (range 180 -240). Left atrial volume 32 mL/m2 (+/- 7 SD), and mean left atrial posterior wall area 22 cm2 (+/- 4 SD). Data was available for quantitative assessment of the extent of ablation for eight patients. No lesions (0 of 32) were ostial in nature. The antral surface area of ablation was not statistically different between the left and right sided pulmonary veins (p 0.63), which were 5.9 (1.6 SD) and 5.4 (2.1 SD) cm2 respectively. In total 50% of the posterior left atrial wall was ablated. Conclusion Pulmonary vein isolation using a novel BCC provides a wide and antral lesion set. There is significant debulking of the posterior wall of the left atrium. Abstract Figure.

Functional studies of left atrium and BNP in patients with paroxysmal atrial fibrillation and the prediction of recurrence after CPVA.

This study was aimed to observe the significance of the left atrium (LA) functional index combined with B-type natriuretic peptide (BNP) level in predicting recurrence in patients with paroxysmal atrial fibrillation (PAF) after circumferential pulmonary vein ablation (CPVA). Real-time three-dimensional echocardiography (RT-3DE) was used to observe the structural and functional changes of LA in patients with PAF after CPVA. BNP is a hemodynamic indicator of myocardial stretching increase in atrial fibrillation (AF) patients. 243 patients with PAF who intended to undergo CPVA were selected in the study, and the following clinical data of the patients were collected. Firstly, the blood BNP levels measured before CPVA. Secondly, the measurements of routine echocardiography before CPVA. RT-3DE was used to obtain the time-volume curve of LA. Then, multivariate logistic regression analysis was used to analyze the factors affecting PAF recurrence after CPVA. Finally, we obtained the receiver operating characteristic (ROC) curve of PAF recurrence predicted by the independent risk factors. A total of 233 AF patients with an average age of 63.1 ± 9.3 years (range, 39-75 years; male: female =195: 38) underwent CPVA. 42 patients had AF recurrence (18.0%) during 3-6months follow-up after an operation blanking period of 3 months, BNP in the Recurrence Group was higher than that in Sinus Rhythm Group (p≤0.001). The preoperative left minimum volume index (LAVImin), left atrial volume index before contraction (LAVIpre-a) were higher in Recurrence Group than in Sinus Rhythm Group (p≤0.001). Expansion index, Diastolic emptying index (DEI), Passive emptying index (PEI), Active emptying index (AEI) were lower in the Recurrence Group than in the Sinus Rhythm Group (p≤0.001). Logistic regression analyses showed that BNP and DEI were independent predictors for PAF recurrence (OR=1.004, 95% CI: 1.01-1.07, p=0.001; OR=0.655, 95% CI: 0.57-0.75, p=0.001). The AUC of BNP, DEI and combined index for recurrence of CPVA were higher than LAVImax (p range: 0.001-0.013). In patients with PAF treated with CPVA, the impaired DEI of LA reservoir function and increased BNP may be useful predictors of PAF recurrence.

Depression and recurrence of atrial fibrillation after catheter ablation: a meta-analysis of cohort studies

Background: The influence of depression on the recurrence of atrial fibrillation (AF) after catheter ablation remains unclear. We performed a meta-analysis to evaluate the association between depression and AF recurrence after catheter ablation. Methods: Cohort studies that evaluated depression at baseline and correlated depression with AF recurrence after catheter ablation were identified by searching the PubMed and Embase databases. Heterogeneity was determined using the Cochrane's Q test and calculating the I2 statistic. A random-effect model was applied to incorporate the potential influence of heterogeneity. Results: Our analysis included seven cohort studies with 1,070 AF patients who underwent catheter ablation by circumferential pulmonary vein isolation. No significant heterogeneity was detected among the included studies (p for Cochrane's Q test = 0.20, I2 = 29%). Pooled results showed that depression before procedure was independently associated with increased risk of AF recurrence after catheter ablation (adjusted relative risk [RR]: 2.24, 95% confidence interval [CI]: 1.75 - 2.88, p < 0.001). Sensitivity analyses, conducted by omitting one study at a time, retrieved similar results (RR: 2.06 - 2.53, p all < 0.05). Predefined subgroup analyses showed that the association between depression and AF recurrence after catheter ablation was consistent regardless of the study characteristics, including study location, study design, patient number, type of AF, follow-up duration, adjustment of left atrial dimension, and quality score. Limitations: This analysis included a limited number of studies and various instruments applied to measure depression. Conclusions: Depression is an independent risk factor of AF recurrence after catheter ablation.

Clinical efficacy of "ICE-FIRE" ablation for non-paroxysmal atrial fibrillation.

Catheter ablation is less successful for non-paroxysmal atrial fibrillation (NPAF) according to numerous follow-up studies. The choice of ablation strategy for patients with NPAF remains controversial. The objective of the study was to explore the clinical efficacy of the "ICE-FIRE" ablation. Ninety NPAF patients were enrolled. Patients were randomly divided into RF (treated with circumferential pulmonary vein isolation (CPVI) and additional substrate modification by radiofrequency ablation) group and I-F (treated with CPVI by cryoablation and additional substrate modification by radiofrequency ablation) group. After CPVI and cardioversion to sinus rhythm, high-density mapping was performed. Eight-one of 90 participants restored to sinus rhythm. Seventy-four of 81 NPAF patients showed low-voltage zone. Substrates with low-voltage zone were targeted for further modification. Participants were followed at baseline, 3, 6, 9, and 12months after the initial ablation. The I-F group shared more X-ray exposure (I-F, 264.4 ± 97.4mGy; RF, 224.9 ± 62.0mGy; P = 0.039) and less duration of the procedure (I-F, 150.3 ± 27.5min; RF, 174.2 ± 38.5min; P = 0.003) compared to RF group. The freedom from atrial arrhythmia recurrence at 12months post-ablation was similar between the RF and I-F groups (RF, 57.1%; I-F, 71.8%; P = 0.197). However, I-F group experienced lower rehospitalization rate of AF recurrence (RF, 42.9%; I-F, 20.5%; P = 0.038). In NPAF patients requiring substrate mapping and modification, the "ICE-FIRE" ablation demonstrated non-inferior clinical efficacy and lower rehospitalization rate of AF recurrence when compared with pure radiofrequency ablation strategy.

Is Catheter Ablation Better Than Antiarrhythmic Drugs for the Treatment of Atrial Fibrillation?

Long-standing atrial fibrillation is associated with significant morbidity including stroke and development of heart failure. Patients also report poor quality of life as a result of debilitating symptoms or treatment side effects from antiarrhythmic medications. Radio frequency or cryothermal mediated catheter ablation has a central role in the management of symptomatic patients with paroxysmal or persistent atrial fibrillation. Circumferential pulmonary vein isolation is vital to the success of this therapy and other ancillary techniques have been described, especially for persistent atrial fibrillation. Several randomized controlled studies have been reported over the last two decades studying important clinical outcomes in patients with atrial fibrillation. In this article, we aim to provide a review of the major studies that have helped define the role of catheter ablation in the management of symptomatic atrial fibrillation in patients with both diseased and structurally normal hearts.

CT EVALUATION OF THE LEFT ATRIAL POSTERIOR WALL AND POSTOPERATIVE ATRIAL ARRHYTHMIAS FOLLOWING ABLATION

Posterior wall isolation (PWI), in addition to circumferential pulmonary vein ablation (CPVA), increases the efficacy of ablation in patients with persistent atrial fibrillation. We sought the utility of cardiac computed tomographic (CT) imaging in the evaluation of recurrent, postoperative atrial

A square root pattern of changes in heart rate variability during the first year after circumferential pulmonary vein isolation for paroxysmal atrial fibrillation and their relation with long‑term arrhythmia recurrence.

An incidental lesion of the parasympathetic ganglia during circumferential pulmonary vein isolation (CPVI) may affect heart rate variability (HRV). We studied the pattern of changes in HRV parameters and the relationship between the 1‑year HRV change following CPVI and the recurrence of atrial fibrillation (AF). A total of 100 consecutive patients undergoing CPVI for paroxysmal AF were enrolled (mean [SD] age, 56 [11.2] years; 61 men). We measured HRV on the day before and after CPVI, and then at 1 month as well as 3, 6, and 12 months after CPVI using 24‑hour Holter monitoring. During the median follow‑up of 33 months, 38 patients experienced the late recurrence of AF (LRAF). Compared with the pre‑CPVI values, HRV was significantly attenuated on day 1 after CPVI in all patients. However, at 3 to 6 months after CPVI, all HRV parameters remained significantly decreased in LRAF‑free patients but not in those with LRAF. The multivariate Cox analysis showed that early AF recurrence within the blanking period (hazard ratio [HR], 4.87; 95% CI, 2.44–9.69; P <0.001) and a change in the standard deviation of normal‑to‑normal intervals (SDNN) observed 3 months after ablation (HR, 0.99; 95% CI, 0.98–1; P = 0.01) were associated with LRAF. The cumulative LRAF freedom after CPVI was greater in patients with an SDNN reduction of more than 25 ms reported 3 months after ablation than in those with a reduction of 25 ms or lower (log‑rank P = 0.004). Sustained parasympathetic denervation during 12 months after CPVI was a marker of successful CPVI, whereas a 3‑month post‑CPVI SDNN reduction of 25 ms or lower predicted LRAF.

Segmental Versus Circumferential Ablation of Pulmonary Veins in Patients with Paroxysmal Atrial Fibrillation

INTRODUCTION: Pulmonary vein isolation (PVI) is the cornerstone of catheter ablation techniques for the treatment of paroxysmal atrial fibrillation (PAF), with significantly improved efficacy compared to antiarrhythmic drugs as shown in CABANA trial. However, the question arises in which PAF patients whether the procedure can be limited to PVs only showing potentials (segmental), or it is really necessary to isolate all PV (circumferential). Even though success rates for circumferential PV ablation (CPVA) have been reported to be higher (up to 90%), than segmental PV ablation, most CPVA procedures previously reported included left atrial linear ablation, additional ablation lesions or lines connecting the mitral valve to the posterior PVs or along the roof of the left atrium which made bias to these studies.&#x0D; AIM: Thus, we initiated this randomized controlled study to evaluate the efficacy of CPVA versus SPVI in subjects undergoing ablation of PAF.&#x0D; METHODS: Our study included 31 consecutive patients who underwent their first radiofrequency ablation for PAF between March 2015 and March 2017. Patients were randomized for circumferential or segmental ablation on the day of the procedure. We had two groups, circumferential (17 patients) and segmental group (14 patients).&#x0D; RESULTS: There was no difference between two groups on our primary endpoint, the recurrence, which was 2 out of 14 patients (14.3%) in the segmental ablation group, compared to 3 out of 17 patients (17.6%) who were circumferential ablated. This difference is statistically insignificant (p = 1). For other endpoints, there was also no statistically significant difference between circumferential and segmental regarding fluoroscopy time, 53.47 ± 8.7 min versus 54.93 ± 15.02 min, p = 0.738, procedure time, 184.18 ±19.28 min versus 191.43 ± 20 min p = 0.315, and even for radio frequency time which was lower in segmental group but did not differ statistically, 35.71 ± 5.73 min versus 34.79 ± 5.29, min p = 0.649.&#x0D; CONCLUSION: The previous studies showed the superiority of circumferential PVI on segmental strategy regarding effectiveness, but in those studies, linear ablations were added to circumferential strategy and done in cases of persistent and PAF. In our randomized study, we compared between two methods in cases of PAF, which showed that segmental ablation is not inferior to circumferential ablation of PVI.

Circumferential pulmonary vein antrum ablation for the treatment of paroxysmal atrial fibrillation: A randomized controlled trial.

It remains unclear whether the curative result of paroxysmal atrial fibrillation (PAF) is a result of pulmonary vein (PV) isolation, PV antrum modification (PVAM), or both. We hypothesized that sufficient antrum modification (PVAM) is as important as PV isolation (PVI) for atrial fibrillation (AF) control and that PVAM can be evaluated by quantified lesion deployment using a force-sensing catheter. Patients of symptomatic PAF were randomly assigned 2:1 into a PVAM group or a circumferential PV isolation (CPVI) group. In the PVAM group, circumferential quantitative ablation evaluated by automatical VisiTag module was performed. In the CPVI group, conventional circumferential ablation was performed to achieve the end point of all-PV isolation. In total, 180 patients with PAF were enrolled and randomly assigned to either the PVAM group (n=120) or the CPVI group (n=60). A total of 179 patients successfully underwent ablation. In the PVAM group, 68 patients achieved all PVI (PVAM-PVI), while 51 did not (PVAM-non-PVI). At 18 months, there was no significant difference in the maintenance of sinus rhythm between the PVAM and CPVI groups (84.9vs 79.7%, P=.382). The PVAM-PVI subgroup demonstrated a higher arrhythmia-free survival compared with the PVAM-non-PVI subgroup (92.6vs 74.5%, P=.006) and the CPVI group (92.6 vs 79.7%, P=.036). The trial shows that sufficient force-sensing guided PVAM can result in satisfying outcomes in PAF patients. Notably, sufficient PVAM with all-PV isolated will further increase the success rate.

Homogenization of low voltage aereas for the ablation of persistent atrial fibrillation

Current ablation strategies for persistent AF have shown a limited success rate with frequent arrhythmia recurrences. STAR-AF 2 trial assessed that PVI-only is as effective as other ablation strategies. Recent studies suggest that the atrial arrhythmogenic sites are related to regions with heterogeneities and increased fibrosis which is detected by reduced bipolar voltage areas. Targeting low voltage areas in addition to PVI may represent an efficient strategy for the ablation of persistent AF. We prospectively included patients with symptomatic persistent AF (mean age: 60.8 ± 4.2 years, men 78%). The ablation strategy consisted of circumferential pulmonary vein isolation (CPVI). Sinus rhythm was restored by electrical cardioversion. A voltage map was performed in sinus rhythm. Complementary RFA was guided by low voltage areas (0.2–0.4 mV). Success was defined as freedom from AF/atrial flutter or atrial arrhythmia for a period ranging from 3 months to 12 months or more. 55 patients were included with persistent AF. Procedure time was: 154 ± 25 min and fluoroscopy time: 184 ± 90 sec. Time of RFA was 44.7 ± 12.7 min. Mean LA volume was 195 ± 35 mL. Low voltage areas were identified in 41.5% of pts. AF was not inducible for 81.8% of pts. After a single procedure at a mean FU of 12 months, 71% of patients were free of symptomatic AF. Predictive factors of recurrence of AF were large left atrial volume (> 205 mL), shorts AF cycle length (< 168 ms) and reduce LEVF (< 45%). 5.5% of the pts presented atrial tachycardia, and re-ablated with success. These results suggest that PVI with complementary RF ablation guided on low voltage areas is an efficient strategy for symptomatic persistent AF.

Avoidance of Vagal Response During Circumferential Pulmonary Vein Isolation: Effect of Initiating Isolation From Right Anterior Ganglionated Plexi.

Circumferential pulmonary vein isolation (CPVI) often cause unavoidable vagal reflexes during procedure due to the coincidental modification of ganglionated plexus which are located on pulmonary vein (PV) antrum. The right anterior ganglionated plexi (RAGP) which located at superoanterior area of right superior PV antrum is an essential station to regulate the cardiac autonomic nerve activities and is easily coincidentally ablated during CPVI. The aim of this study is to assess the effect of RAGP ablation on vagal response (VR) during CPVI. A total of 80 patients with paroxysmal atrial fibrillation who underwent the first time CPVI were prospectively enrolled and randomly assigned to 2 groups: group A (n=40), CPVI started with right PVs at RAGP site; group B (n=40): CPVI started with left PVs first, and the last ablation site is RAGP. Electrophysiological parameters include basal cycle length, A-H interval, H-V interval, sinus node recovery time, and atrioventricular node Wenckebach point were recorded before and after CPVI procedure. During CPVI, the positive VR were only observed on 1 patient in group A and 25 patients in group B (P<0.001). A total of 21 patients with positive VR in group B needed for temporary ventricular pacing during procedure, while the only patient with positive VR in group A did not need for temporary ventricular pacing (P<0.001). Compared with baseline, basal cycle length, sinus node recovery time, and atrioventricular node Wenckebach point were decreased significantly after CPVI procedure in both groups (all P<0.05) and without differences between 2 groups. Circumferential PV isolation initiated from RAGP could effectively inhibit VR occurrence and significantly increase heart rate during procedure.

Long-Term Outcome of Additional Superior Vena Cava to Septal Linear Ablation in Catheter Ablation of Atrial Fibrillation.

BackgroundWe previously reported the benefit of linear ablation from the superior vena cava to the right atrial septum (SVC‐L) within a year after circumferential pulmonary vein isolation (CPVI) in patients with paroxysmal atrial fibrillation (AF). We explored the long‐term effects of SVC‐L and its potential related mechanisms.Methods and ResultsAmong 2140 consecutive patients with AF ablation, we included 614 patients (73.3% male, aged 57.8±10.7 years, 13.7% with persistent AF) who did not undergo an extra–pulmonary vein left atrial ablation after propensity score matching; of those, 307 had additional SVC‐L and 307 had CPVI alone. We evaluated the heart rate variability and computational modeling study to explore mechanisms. Although the procedure time was longer in the SVC‐L group than the CPVI group (P<0.001), the complication rates did not differ (P=0.560). During 40.5±24.4 months of follow‐up, the rhythm outcome was significantly better in the SVC‐L group than the CPVI group (log rank, P<0.001). At 2‐year follow‐up of heart rate variability, a significantly higher mean heart rate (P=0.018) and a lower ratio of low/high‐frequency components (P=0.011) were found with SVC‐L than CPVI alone. In realistic in silico biatrial modeling, which reflected the electroanatomies of 10 patients, SVC‐L significantly reduced biatrial dominant frequency compared with CPVI alone (P<0.001) and increased AF termination and defragmentation rates (P=0.033).Conclusions SVC‐L ablation in addition to CPVI significantly improved the long‐term rhythm outcome over 2 years after AF catheter ablation by mechanisms involving autonomic modulation and AF organization.

High-power application is associated with shorter procedure time and higher rate of first-pass pulmonary vein isolation in ablation index-guided atrial fibrillation ablation.

Ablation index (AI) is useful to complete circumferential pulmonary vein isolation (CPVI) for atrial fibrillation (AF), but the role of radiofrequency power in AI-guided CPVI remains to be elucidated. We investigated 60 patients with AF undergoing AI-guided CPVI (mean age, 66 ± 9 years; nonparoxysmal AF in 16). The first 40 patients were randomly assigned to low-power (LP; n = 20) and medium-power (MP; n = 20) groups and the following 20 patients to high-power (HP). In LP, radiofrequency (RF) application was done at 30 W at the anterior and 20 W at the posterior left atrial (LA) wall, while in MP, it was at 40 W at the anterior and 30 W at the posterior LA wall. In HP, 50 W was applied at the anterior, 40 W at posterior LA wall and 30 W on the esophagus. At each ablation point, target AI was 400 at the anterior, 360 at the posterior LA wall, and 260 on the esophagus. The time to complete both-side CPVI was shortest in HP (median, 40 minutes, interquartile range [IQR], 28-63) followed by MP (58 [49-83] minutes, P = .008 vs HP) and LP (84 [72-93] minutes, P = .002 vs MP). Higher RF power application significantly increased first-pass isolation rate (55% in LP, 80% in MP and 85% in HP, P = .002) and decreased LA-PV reconnection rate (10% in LP, 8% in MP, and 0% in HP, P = .03). In AI-guided PVI, the HP RF application can shorten the time to complete PVI with a high rate of first-pass isolation and a low rate of LA-PV reconnection.

P4798Stereotactic radiotherapy for atrial fibrillation in three cancer patients

Abstract Background Although catheter ablation is an effective therapy for atrial fibrillation (AF), risks remain and improved efficacy is desired. Stereotactic radiotherapy is a well-established therapy used to noninvasively treat malignancies with precision. Objective We sought to evaluate stereotactic arrhythmia radioablation (STAR) as a therapeutic option for treating AF. Methods Three cancer patients with drug refractory AF were enrolled. Planning software using 3-D CT of the left atrium was used to design a desired ablation volume encompassing antral circumferential pulmonary vein isolation, a roof line, and a floor line to create a “BOX” lesion set. Target dose to the treatment volume was 25 Gy, with exposure to the esophagus excluded. After planning, patients were treated in the radioablation suite. Results STAR was able to deliver the intended radiation dose to target without complication in 3 patients. No acute complications were seen for up to 6 months. One patient with paroxysmal AF died of deterioration of cancer. The autopsy revealed evidence of fibroblasts and fibrogenesis at the regions of atrial tissues targeted with radioablation. Two patients with longstanding persistent AF remained in AF at 6 months. In one patient, atrial electrograms were recorded at the atrial posterior wall from the esophagus before STAR, and it was absent at 3 months after STAR, indicating electrical isolation. BOX isolation created by STAR Conclusions Although STAR may be safe, further evaluation is warranted regarding effectiveness. For longstanding persistent AF, AF may be difficult to terminate only with a BOX lesion set without electrical cardioversion.

P2466The impact of circumferential pulmonary vein isolation on global and regional left atrial function in patients with paroxysmal atrial fibrillation

Abstract Introduction The effect of circumferential pulmonary vein isolation (PVI) for atrial fibrillation (AF) on left atrial (LA) function has not been well defined. Purpose The aim of this study was to evaluate the immediate impact of ablation on parameters of global and regional LA function using intracardiac echocardiography (ICE) Methods We studied 26 consecutive patients (age 56±10 years, 19 men) with paroxysmal AF using ICE before and immediately after circumferential PVI. All pulmonary veins were isolated in all patients. ICE measurements included LA fractional area shortening, peak A wave on transmitral Doppler flow, peak emptying velocity on the left atrial appendage (LAA) Doppler flow, as well as tissue Doppler myocardial velocities at the level of the posterior LA wall, interatrial septum, and lateral wall, which were used as parameters of regional LA function. Results The mean radiofrequency ablation time was 37±22min. Post ablation there was a significant reduction of the LA fractional area shortening from 27±8% to 22±6% (p&lt;0.01). The tissue Doppler velocity of atrial contraction at the posterior wall decreased significantly post ablation: from 8.9±1.8 cm/s to 6.9±1.4 cm/s (p&lt;0.01). There were no significant differences between the pre and post ablation values for tissue Doppler velocities at the level of the interatrial septum or LA lateral wall. The post ablation peak transmitral A wave and peak LAA Doppler velocities did not differ significantly from the pre ablation values. Conclusion In patients with paroxysmal atrial fibrillation, circumferential PVI results in an immediate decrease in LA function without a significant change in LAA function.

P2841Atrial fibrillation ablation using ablation index guided high power (50W) smart touch technology for quantifiable and efficient circumferential pulmonary vein lesions (the FAFA power-touch study)

Abstract Background High-power short-duration ablation appears a promising concept. The so-called ablation index (AI) integrating power, contact force and time have demonstrated increased pulmonary vein isolation (PVI) durability. However, feasibility and safety of AI guided high-power ablation is unknown. Methods and results Symptomatic AF patients (n=50) underwent circumferential PVI using AI guided high-power point-by-point ablation (CARTO Smart-Touch). Ablation was set to 50W targeting AI values (550: anterior wall/roof, 400: posterior wall) with an inter-lesion distance of 6mm using a non-steerable sheath. An esophageal probe monitored luminal temperature rises (limit: 39°C). Acute PVI was obtained in all patients; first-pass efficacy was 92%. Mean ablation time per procedure was 11.2±2.2 min, mean procedure time was 55.6±6.6 min. A total of 2105 lesions were analyzed, comparing left anterior wall vs. left posterior wall and right anterior wall vs. right posterior wall, the mean ablation time (sec.) was 20.5±8.2 vs. 8.6±3.2, and 12.2±4 vs 9.3±3.4; the mean contact force (g): 17.1±12 vs 25.4±14.2 and 33.7±13.1 vs 21.0±10.5, the mean AI: 546.8±48.2 vs 444.6±55 and 554.8±56 vs. 439.8±47.1 (all P&lt;0.0001). Audible steam pops were noted in in 4 (8%) patients. Esophageal temperature rise &gt;39°C were noted in 25 (50%) patients. In 1/50 (2%) patient a minor esophageal lesion after ablation was observed without requiring specific therapy. No major complications such as death, stroke, tamponade or atria-esophageal -fistula occurred. Conclusion The novel AI guided high power ablation appears to be a feasible, safe, quantifiable and efficient strategy for PVI.