Abstract 2753: The Relationship Between Pulmonary Vein Antrum Scarring Following Atrial Fibrillation Ablation and Procedural Success: Does Pulmonary Vein Isolation Matter?

Background. A mechanism of atrial fibrillation (AF) recurrence following ablation may be incomplete pulmonary vein antrum (PVA) scarring that allows for conduction between the pulmonary veins (PV) and the left atrium (LA). We report the relationship between circumferential PV scarring detected by delayed enhancement MRI (DE-MRI) and AF recurrence following PVAI. Methods. Eighty-six patients presenting for PVAI underwent DE-MRI 3 months post ablation. Circumferential ablation with posterior wall debulking was performed in all patients. PV ostia were marked on 3D images generated from the MRI data and assessed by consensus of two independent reviewers for the extent of scarring. Complete PVA scarring was defined as a continuous ring of enhancement surrounding the PVA. For patients with incomplete scarring, the degree of scarring was estimated. Results. The figure shows two patients from the cohort, Patient 1 exhibits successful scarring of all PVA. Patient 2 shows scarring of 1 PVA. At three months post ablation, complete circumferential lesion was seen on 131/335 PVA (39.1%). Complete scarring of 4 PVA was seen in 9 patients (10.5%), scarring of 3 PVA in 11 patients (12.8%) and scarring of 2 PVA was seen in 17 patients (19.8). Twenty-nine patients (33.7%) exhibited complete scarring in 1 PVA while 20 patients (23.3%) exhibited scarring in 0 PVA. Kaplan Meier analysis (Figure [E] ), suggests that PVA isolation may be important for long-term procedural success. Conclusion: Complete pulmonary vein antrum scarring exists in a very limited number of patients, despite its apparent importance for long-term procedural success.

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

EP Europace ◽

10.1093/europace/euaa162.203 ◽

2020 ◽

Vol 22 (Supplement_1) ◽

Author(s):

A P Martin ◽

M Fowler ◽

N Lever

Keyword(s):

Atrial Fibrillation ◽

Left Atrium ◽

Pulmonary Vein ◽

Pulmonary Vein Isolation ◽

Paroxysmal Atrial Fibrillation ◽

Left Atrial ◽

Pulmonary Veins ◽

Posterior Wall ◽

The Novel ◽

Median Treatment

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.

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Pulmonary Vein Activity Organization to Determine Atrial Fibrillation Recurrence: Preliminary Data from a Pilot Study

Mathematics ◽

10.3390/math8101813 ◽

2020 ◽

Vol 8 (10) ◽

pp. 1813

Author(s):

Raquel Cervigón ◽

Javier Moreno ◽

José Millet ◽

Julián Pérez-Villacastín ◽

Francisco Castells

Keyword(s):

Atrial Fibrillation ◽

Pulmonary Vein ◽

Cross Correlation ◽

Spatial Organization ◽

Pulmonary Veins ◽

Transfer Entropy ◽

First Year ◽

Atrial Fibrillation Recurrence ◽

Ablation Procedure ◽

Af Recurrence

Ablation of pulmonary veins has emerged as a key procedure for normal rhythm restoration in atrial fibrillation patients. However, up to half of ablated Atrial fibrillation (AF) patients suffer recurrences during the first year. In this article, simultaneous intra-atrial recordings registered at pulmonary veins previous to the ablation procedure were analyzed. Spatial cross-correlation and transfer entropy were computed in order to estimate spatial organization. Results showed that, in patients with arrhythmia recurrence, pulmonary vein electrical activity was less correlated than in patients that maintained sinus rhythm. Moreover, correlation function between dipoles showed higher delays in patients with AF recurrence. Results with transfer entropy were consistent with spatial cross-correlation measurements. These results show that arrhythmia drivers located at the pulmonary veins are associated with a higher organization of the electrical activations after the ablation of these sites.

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P984Residual gaps in the ablation line and requirement for carina ablation during contact force-guided radiofrequency pulmonary vein isolation: determinants and prognostic implications

European Heart Journal ◽

10.1093/eurheartj/ehz747.0577 ◽

2019 ◽

Vol 40 (Supplement_1) ◽

Author(s):

M J Mulder ◽

M J B Kemme ◽

M J W Gotte ◽

H A Hauer ◽

G J M Tahapary ◽

...

Keyword(s):

Pulmonary Vein ◽

Pulmonary Vein Isolation ◽

Contact Force ◽

Pulmonary Veins ◽

Survival Analyses ◽

Kaplan Meier ◽

Significant Difference ◽

Prognostic Implications ◽

Ablation Line ◽

Af Recurrence

Abstract Background Pulmonary vein isolation (PVI) is not always achieved after initial encircling of the pulmonary veins (PVs). Additional touch-up lesions are frequently required to close residual gaps, which may occur both in the initial ablation line and on the intervenous carina. Purpose We aimed to identify determinants and prognostic implications of residual gaps during index radiofrequency PVI. Methods Two hundred fourteen AF (atrial fibrillation) patients (57% paroxysmal, 61% male, mean age 62±9 years) undergoing contact force-guided PVI were studied. Residual gaps after initial encircling of the PVs were targeted for additional ablation and were classified as either gap ablation in the initial WACA (wide-area circumferential ablation) circle or carina ablation, depending on the site of earliest activation. After a waiting period of at least 30 minutes, persistence of PVI was tested through administration of 9–18 mg intravenous adenosine. Pre-procedural cardiac computed tomography imaging was used to assess left atrial and PV anatomy. Carina width was defined as the distance between ipsilateral superior and inferior PV ostia. Ablation procedures were analyzed to define the perimeter of the WACA circle. Results One hundred thirty-three patients (62%) required additional ablation lesions beyond the initial WACA circles to achieve complete PVI. Gap ablation was required in the left WACA circle in 34 patients (16%) and in the right WACA circle in 49 patients (23%). Left and right carina ablation were required in 50 (23%) and 83 (39%) patients, respectively. Multivariate analyses identified carina width and perimeter of the WACA circle as independent predictors of requirement for ipsilateral carina ablation, whereas paroxysmal AF and the perimeter of the WACA circle were associated with requirement of gap ablation in the initial WACA circle. Recurrence of atrial tachyarrhythmias was documented in 73 patients (34%) at 12 months follow-up. Kaplan–Meier survival analyses demonstrated a significantly higher rate of recurrence in patients with one or more residual gaps in the ablation line (43% vs. 30%, p=0.019, figure A), whereas no significant difference between patients with and without requirement of carina ablation was found (38% and 29%, respectively; p=0.111, figure B). Kaplan-Meier survival analyses Conclusion Residual gaps in the initial WACA circle were associated with increased AF recurrence rate after PVI, whereas residual gaps on the intervenous carina had no statistically significant impact on AF recurrence. Consequently, gaps occurring in the ablation line and gaps on the intervenous carina may represent different mechanisms and may have different prognostic implications.

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P1913Implantable Loop Recorder Detected Pattern of Atrial Fibrillation Recurrence Following Cryoballoon Pulmonary Vein Isolation in Patients with Persistent Atrial Fibrillation

European Heart Journal ◽

10.1093/eurheartj/ehz748.0660 ◽

2019 ◽

Vol 40 (Supplement_1) ◽

Author(s):

D Musat ◽

N Milstein ◽

R Shaw ◽

A Bhatt ◽

M Preminger ◽

...

Keyword(s):

Atrial Fibrillation ◽

Pulmonary Vein ◽

Pulmonary Vein Isolation ◽

Persistent Atrial Fibrillation ◽

Limited Data ◽

Loop Recorder ◽

Long Term Follow Up ◽

Af Recurrence

Abstract Background Cryoballoon (CB) pulmonary vein isolation (PVI) is increasingly being used in patients (pts) with persistent atrial fibrillation (AF). However, there are limited data about the pattern of atrial fibrillation (AF) recurrence in these pts. Objective To assess, using an implantable loop recorder (ILR), the patterns of AF recurrence following CB PVI in pts with persistent atrial fibrillation. Methods We enrolled consecutive pts with persistent AF ablation undergoing their first CB ablation. Other cavotricuspid isthmus ablation when indicated, no other ablation was performed. A Reveal LINQ ILR (Medtronic) was implanted <3 months following ablation; all pts had a minimum of 1-year follow-up. The recurrence of any atrial arrhythmia was determined and adjudicated; 4 distinct AF patterns were characterized (Figure). Results We studied 64 pts (66±9 years; 50 [78%] male; CHA2DS2-VASc 2.6±1.9) with persistent AF; 52 (81%) pts were on an antiarrhythmic drug (AAD) peri-ablation. During 803±361 days of follow-up, 33 (52%) pts had their 1st AF recurrence 91–365 days post-ablation and another 17 (27%) pts had their 1st AF recurrence >365 days post-ablation. No AF was seen in 14 (31%) pts. Most pts (33 of 50, 66%) with AF recurrence presented with 1 of 3 distinct patterns of paroxysmal AF (Figure), which ranged from 22 min to 124 hours. In 2/3 of these pts, all AF recurrences lasted <24 hours. Only 17 (34%) pts recurred with persistent AF. Conclusion Following single CB PVI, most pts with persistent AF remained free of persistent AF during long-term follow-up. Most pts with recurrent AF have 1 of 3 distinct patterns with episodes commonly last <24 hours. These data suggest that CB PVI ablation may halt AF progression in pts initially presenting with persistent AF.

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Abstract 19348: Efficacy of Cryoballoon Pulmonary Vein Isolation in Patients With Persistent Atrial Fibrillation

Circulation ◽

10.1161/circ.132.suppl_3.19348 ◽

2015 ◽

Vol 132 (suppl_3) ◽

Author(s):

Emily Guhl ◽

Donald Siddoway ◽

Evan Adelstein ◽

Samir Saba ◽

Andrew Voigt ◽

...

Keyword(s):

Atrial Fibrillation ◽

Pulmonary Vein ◽

Pulmonary Vein Isolation ◽

Persistent Atrial Fibrillation ◽

Free Survival ◽

Kaplan Meier ◽

Initial Strategy ◽

Free Rate ◽

Af Recurrence

Introduction: Cryoballoon pulmonary vein isolation (PVI) has emerged as an alternative to radiofrequency PVI for the treatment of paroxysmal atrial fibrillation (AF). The optimal ablation strategy for patients with persistent AF is unclear, as data on Cryoballoon PVI alone are limited. Methods: We analyzed a prospective registry of consecutive patients with persistent AF who underwent Cryoballoon PVI at a single center between 2011 and 2014. Patients were assessed for AF recurrence (including any atrial arrhythmia) after a 3 month blanking period at 6 months, 1 year, 2 years, and as needed for symptoms post PVI. Recurrence was based on typical symptoms or ECG/ event monitor evidence of AF. Kaplan-Meier analysis was used to estimate AF-free survival. Results: The 69 patients who underwent Cryoballoon PVI were aged 59 ± 8 years, 86% male, 54% HTN, had a CHADS2-VASC score 1.6 ± 1.2, and had a LA dimension 4.5 ± 0.6 cm. The AF recurrence-free rate at 1-year post-procedure was 59%. Overall, AF-free survival was 50% at the mean follow-up of 607 days. In comparing patients with persistent AF duration <1 year vs. >1 year, there was a trend toward greater AF recurrence-free rates in the <1 year group (66% vs 55%, p=0.09) Conclusions: Cryoballoon PVI appears to be an effective initial strategy in treating persistent AF, with an AF recurrence-free rate of 59% at 1 year.

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Abstract 2756: Prevention of Atrial Fibrillation Recurrence after Radiofrequency Catheter Procedure of Pulmonary Vein Isolation by Corticosteroids

Circulation ◽

10.1161/circ.118.suppl_18.s_772-b ◽

2008 ◽

Vol 118 (suppl_18) ◽

Author(s):

Takashi Koyama ◽

Yukio Sekiguchi ◽

Hiroshi Tada ◽

Takanori Arimoto ◽

Hiro Yamasaki ◽

...

Keyword(s):

Atrial Fibrillation ◽

Placebo Group ◽

Pulmonary Vein ◽

Pulmonary Vein Isolation ◽

Therapeutic Option ◽

Artery Bypass ◽

Underlying Mechanism ◽

Control Group ◽

Number Of Patients ◽

Af Recurrence

Background: Catheter based radiofrequency pulmonary vein isolation (PVI) has been shown to be an effective therapeutic option for controlling drug-refractory atrial fibrillation (AF); however, the recurrence of AF has become one of the major problems after procedure. Although the underlying mechanism of the AF recurrence is not well evaluated, previous reports indicated that inflammatory process could be associated with the onset of AF and the use of intravenous hydrocortisone reduced the incidence of AF after coronary artery bypass surgery. We therefore prospectively evaluated the efficacy of the hydrocortisone for the prevention of AF recurrence. Methods and Results: This study included consecutive 150 patients with drug-refractory paroxysmal AF. Patients were randomized to receive either hydrocortisone or matching placebos as follows: intravenous hydrocortisone (dose of 2mg/kg) was used in the day of operation, and oral hydrocortisone was administered (dose of 0.6mg/kg/day) for 3 days after PVI. Patients with non-PV-foci AF were excluded in this study (Control group; 4 patients, Hydrocortisone group; 6 patients). Various biophysical data were closely investigated between control group (n=71) and hydrocortisone group (n=69). Rate of total AF recurrence and immediate AF recurrence (recurrence of AF within 3 days after PVI) was significantly lower in hydrocortisone group than placebo group (total AF recurrence; 27.0% vs 46.1%, immediate AF recurrence; 6.7% vs 29.5%, p<0.01). Number of patients who underwent second PVI (8.3% vs 23.1%, p<0.01), rise of body temperature after the procedure (0.675°C vs 1.633°C, p=0.005), any sign of pericariditis (0% vs 6.4%, p<0.01), high sensitive CRP level after the procedure (1.17mg/dl vs 2.09mg/dl, P=0.015) and the number of patients using antiarrhythmics (classIb, classIII) after the procedure (classIb; 0% vs 6.4%, classIII; 6.7% vs 26.9%, p<0.01) were also significantly lower in hydrocortisone group than in placebo group. Conclusion: Transient use of hydrocortisone immediately after PVI can be one of the therapeutic options for the prevention of acute AF recurrence after PVI to avoid second procedure and/or the additional antiarrhythmic drug therapy.

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Common ostium of the left pulmonary veins – to freeze or not to freeze – that was the question?

In a good rythm ◽

10.5604/01.3001.0010.7497 ◽

2017 ◽

Vol 4 (45) ◽

pp. 33-34

Author(s):

Michał Orczykowski

Keyword(s):

Atrial Fibrillation ◽

Pulmonary Vein ◽

Pulmonary Vein Isolation ◽

Second Generation ◽

Pulmonary Veins ◽

Persistent Atrial Fibrillation ◽

Clinical Results ◽

Common Pulmonary Vein

Second-generation cryoballoon (CB2) - based pulmonary vein isolation (PVI) has demonstrated encouraging clinical results in the treatment of paroxysmal (PAF) and persistent atrial fibrillation (PersAF). Nevertheless, the acute efficacy, safety, and long-term clinical results of CB2-based PVI in patients with a left common pulmonary vein (LCPV) are still a matter of debate. Commented paper by Heeger ChH, et al. analyzes this issue with some practical conclusions.

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Abstract 2755: Increased Efficacy of Catheter Ablation Of Atrial Fibrillation by Using Adenosine to Reveal Dormant Pulmonary Vein Conduction

Circulation ◽

10.1161/circ.118.suppl_18.s_772-a ◽

2008 ◽

Vol 118 (suppl_18) ◽

Author(s):

Laurent Macle ◽

Atul Verma ◽

Paul Novak ◽

Paul Khairy ◽

Mario Talajic ◽

...

Keyword(s):

Atrial Fibrillation ◽

Catheter Ablation ◽

Pulmonary Vein ◽

Pulmonary Veins ◽

Historical Control Group ◽

Historical Control ◽

Control Group ◽

Af Ablation ◽

Dormant Conduction ◽

Af Recurrence

Recurrences of atrial fibrillation (AF) after catheter ablation are frequently associated with recovery of conduction between the pulmonary veins (PV) and the atrium. The recovery of PV conduction could be explained by the presence of dormant conduction between the PV and the atrium. Adenosine can be used during AF ablation procedures to reveal transient re-conduction of the isolated pulmonary vein (dormant PV conduction). We prospectively evaluate the utility of iv adenosine to guide elimination of dormant PV conduction by additional radiofrequency (RF) applications during AF ablation procedures. Thirty-four consecutive patients (30 male; age 51+/−8 years) referred for catheter ablation of drug-refractory AF (Paroxysmal 31/Persistent 3) were studied. Electrical PV isolation (PVI) was performed using Irrigated-tip radiofrequency (RF) ablation and was guided by a circular mapping catheter. After PVI, the presence of dormant conduction in each vein was assessed by injection of 12 mg of adenosine. If dormant conduction was present, additional RF energy was delivered at sites of transient re-conduction. Abolition of the dormant conduction was then demonstrated by repeated injections of adenosine. The recurrence rate of arrhythmia after one procedure was evaluated. The results were compared to an historical control group comprising the previous 34 consecutive patients who underwent PVI without the use of adenosine. Electrical PVI was achieved in 100% of PV’s and all 34 patients underwent the adenosine evaluation. Dormant PV conduction was observed in 17/34 patients and could be eliminated in all by additional RF delivery. Procedural and fluoroscopy times were 163±30 and 49±13 minutes, respectively. After a mean follow-up of 8.0±3.1 months, 6/34 (18%) patients experienced AF recurrence with 28/34 (82%) remaining free of arrhythmia without the use of antiarrhythmic drugs. When compared to the 14/34 patients (41%) from the historical control group who had AF recurrence, a significant reduction was observed (P<0.01). The use of adenosine to guide elimination of dormant PV conduction increases the success rate of AF ablation procedures. This needs to be evaluated in a randomized multicenter trial.

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Safety and outcome of cryoballoon ablation versus radiofrequency catheter ablation of the pulmonary veins in patients with paroxysmal atrial fibrillation

QJM ◽

10.1093/qjmed/hcaa041.027 ◽

2020 ◽

Vol 113 (Supplement_1) ◽

Author(s):

O H M A Riad ◽

T Wong ◽

A N Ali ◽

M T Ibrahim ◽

M A Abdelhamid ◽

...

Keyword(s):

Atrial Fibrillation ◽

Radiofrequency Ablation ◽

Catheter Ablation ◽

Pulmonary Vein ◽

Paroxysmal Atrial Fibrillation ◽

Pulmonary Veins ◽

Cryoballoon Ablation ◽

The Mean

Abstract Background Pulmonary vein isolation (PVI) has become the mainstay of catheter ablation of atrial fibrillation (AF). There are two commonly used methods to isolate the pulmonary veins, either point-by-point delivery of circumferential lesion sets around ipsilateral pulmonary veins using radiofrequency energy, or the application of the cryoballoon to the pulmonary vein antrum with occlusion of the vein ostium. The cryoballoon has proven to be a reliable alternative to radiofrequency ablation in acute and long-term freedom from AF. We describe our results using both modalities. Aim and Objectives to compare the safety and efficacy of cryoballoon (CB) ablation and radiofrequency (RF) ablation in treatment of paroxysmal atrial fibrillation. Patients and Methods Forty-four consecutive patients having paroxysmal AF underwent PVI using the second generation cryoballoon were compared to a retrospective cohort of 69 patients who had radiofrequency induced PVI, either by conventional RF catheter (n = 32), or a contact-force sensing-catheter (n = 37). The study took place at Ain Shams university hospitals and Royal Brompton & Harefield NHS trust. Patient data, procedural data and follow up data- at 3, 6 and 12 months- were collected and analysed. Recurrence was defined as documented AF or atrial arrhythmias with duration exceeding 30 seconds, either by 12 lead ECG or an ambulatory monitoring device. Results A total of 113 patients were studied. The mean age was 53.84 ± 15.01 for the CB group and 55.78 ± 14.84 for the RF group and females representing 40.9% vs 34.8% respectively. The mean procedural times in minutes were significantly less in the CB group (94.37 ± 39.32 vs 184.57 ± 88.19, p < 0.0001), while the median fluoroscopy times were similar [30 (11.04 - 40) vs 37.25 (14.2 - 70), p = 0.172]. Procedural complications were comparable between the two groups (p = 0.06) with 1 patient (2.3%) having long term phrenic nerve paresis. At 1 year follow up, after an initial 90-day blanking period, recurrence rate of CB was similar to RF (27.3% vs 30.4% respectively, p = 0.719), the Kaplan Meier estimates of AF- free survival for a period of 1 year were comparable between both groups (log rank test, p = 0.606). Conclusion Cryoballoon is a feasible method for pulmonary vein isolation with similar success rates to radiofrequency ablation. Cryoballoon ablation is safe with shorter duration of the procedure.

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Using adenosine triphosphate in catheter radiofrequency pulmonary vein isolation: does elimination of “dormant” atriovenous conduction really allow to refine long-term results?

Patologiya krovoobrashcheniya i kardiokhirurgiya ◽

10.21688/1681-3472-2017-4-23-30 ◽

2017 ◽

Vol 21 (4) ◽

pp. 23

Author(s):

Y. S. Krivosheev ◽

D. I. Bashta ◽

A. A. Simonyan ◽

T. A. Myznikova ◽

Z. A. Mishodzheva ◽

...

Keyword(s):

Atrial Fibrillation ◽

Pulmonary Vein ◽

Adenosine Triphosphate ◽

Conflict Of Interest ◽

Pulmonary Veins ◽

Prognostic Significance ◽

Long Term Results ◽

Data Collection And Analysis ◽

Critical Revision

This literature review looks at the efficacy of removing “dormant” atriovenous conduction, which can be identified by means of intravenous ejection of adenosine triphosphate following catheter isolation of pulmonary vein ostia in patients with atrial fibrillation. The incidence of detecting conduction “breakthroughs” in the ablation lines when carrying out drug tests after isolation of pulmonary veins, as well as the prognostic significance of this phenomenon for atrial fibrillation recurrence are evaluated. Also assessed are drawbacks and limitations of the studies looking at the possibility of improving the efficiency of catheter ablation of atrial fibrillation by combining the removal of “dormant” atriovenous conduction zones identified by adenosine triphosphate testing and the ablation of ganglionated plexi.Received 10 April 2017. Accepted 23 October 2017.Funding: The study did not have sponsorship.Conflict of interest: Authors declare no conflict of interest.Author contributions Conception and study design: Y.S. Krivosheev, V.N. Kolesnikov. Data collection and analysis: Y.S. Krivosheev, D.I. Bashta. Drafting the article: Y.S. Krivosheev, A.A. Simonyan. Critical revision of the article: V.N. Kolesnikov. Final approval of the version to be published: Y.S. Krivosheev, D.I. Bashta, A.A. Simonyan, T.A. Myznikova, Z.A. Mishodzheva, V.N. Kolesnikov.

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