Post Pulmonary Vein Isolation Research Articles

Pulmonary hypertension is associated with increased recurrence of atrial fibrillation post-pulmonary vein isolation: a multicenter study insights

Abstract Background Pulmonary vein isolation (PVI) has become an essential therapeutic approach for managing paroxysmal and persistent atrial fibrillation. Besides the fact its application increases, a substantial proportion of patients will suffer from arrhythmia recurrence. Objectives This study aims to determine the clinical and echocardiographic factors that predict fibrillation recurrence following pulmonary vein isolation. Methods In this prospective, multicenter study carried out across 14 medical centers in Israel, we included a cohort of 1002 patients who underwent pulmonary vein isolation from 2019 to 2022. The study involved an assessment of patients' baseline characteristics, electrocardiographic and echocardiographic data, laboratory results, details of the procedure, and their clinical outcomes. We monitored these clinical outcomes for one year after the ablation procedure, focusing mainly on the recurrence of atrial fibrillation, which was verified using electrocardiographic evidence during the post-blanking period. A multivariable analysis revealed the clinical and echocardiographic predictors for atrial fibrillation recurrence post-PVI. Results Our study evaluated 1002 patients with an average age of 64.4 ±11.3 years, including 37.5% females (376 patients). The cohort predominantly, about two-thirds, had paroxysmal AFIB, with an average arrythmia duration of 4.1 years. Frequent pre-existing conditions included ischemic heart disease in 17.3% and congestive heart failure in 13.8% of the patients. Additionally, diabetes was present in a quarter of the cohort, with 9% having a prior cerebrovascular event. The median LVEF was 60 (IQR 53-60), and the average left atrial diameter was 42.6 mm±8.8. The median pulmonary artery pressure was noted at 31 (IQR 25-38), with 13% of patients exhibiting elevated levels above 45 mmHg. Within the first year after the ablation, 11.7% of patients experienced AFIB recurrence in the post-blanking period. Our multivariate COX analysis established clinical and echocardiographic models for predicting post-PVI AFIB recurrence. Gender was a significant predictor, with women showing a higher recurrence rate (HR 1.85, 95% CI 1.29-2.7, P<0.01), in addition to persistent AFIB and a non-sinus rhythm at the time of the procedure. Echocardiographic predictors of recurrence included a left atrial diameter greater than 40 mm (HR 2.16, 95% CI 1.3-3.6, P<0.01) and pulmonary hypertension, notably when pulmonary artery pressure exceeded 55 mmHg, which correlated with almost a fourfold increase in AFIB recurrence risk within the first-year post-procedure (HR 4.25, 95% CI 1.57-11.5, P<0.01). Conclusions Pulmonary hypertension, especially with pulmonary artery pressure above 55 mmHg, significantly elevates the risk of atrial fibrillation recurrence post-pulmonary vein isolation, underscoring its importance in patient prognosis and management.

Abstract 15372: The Lewis Lead

The Lewis lead is a modified ECG configuration that can enhance the amplitude of the atrial electrical activity and is useful when the atrial activity cannot be discerned in the standard ECG. The configuration involves applying the right arm electrode on the manubrium, left arm electrode to the 5th intercostal space on the right sternal border, left leg electrode over the right lower costal margin and right leg electrode in the standard position. The ECG is then interpreted in lead I and II. Herein we present a case where the Lewis lead aided in the diagnosis of complete heart block with underlying atrial fibrillation. Case Presentation: A 75 year old female with severe tricuspid regurgitation was admitted for tricuspid valve replacement. She had previous paroxysmal atrial fibrillation status post pulmonary vein isolation. The preoperative ECG revealed normal sinus rhythm. Postoperatively, ECG demonstrated a narrow complex ventricular rhythm at 70 beats per minute. No atrial activity could be clearly discerned (Image 1). The epicardial atrial wire placed intraoperatively was not functioning, therefore atrial electrogram could not be obtained. It was unclear from repeat ECGs if there was sinus arrest or atrial fibrillation in the atria. The Lewis lead was then utilized and revealed underlying atrial fibrillation (Image 1); together, this was consistent with atrial fibrillation and complete heart block with a junctional escape rhythm. The rhythm did not recover and there was progressive conduction system disease with widening of the QRS and episodes of severe bradycardia. She underwent pacemaker implantation. Discussion: By utilizing the Lewis lead we were able to establish the atrial rhythm and differentiate between atrial fibrillation and sinus arrest. The Lewis lead can also help narrow the differential for wide complex tachycardia by magnifying the p wave, thus making it easier to detect ventriculoatrial dissociation, a hallmark feature of ventricular tachycardia.

Epicardial adiposity in people with atrial fibrillation modified by physical exercise: an umbrella review

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Atrial Fibrillation (AF) affects 30% of the world’s population and accounts for 3 million deaths annually, and current management pathways often result in poor outcomes in recurrence of AF with up to 50% reoccurring post pulmonary vein isolation cardiac ablation (PVICA). Epicardial Adipose Tissue (EAT) is a metabolically active substrate implicated in the pathogenesis of AF. Increased levels of EAT thickness have been associated with the risk of developing AF and has also been associated with poorer outcomes and increased likelihood of AF recurrence after PVICA. The aim of this work was to explore current knowledge on levels of EAT in people with AF, post cardiac ablation, taking account of physical activity (PA). Objectives: Three research questions were set: · Does volume of EAT contribute to the pathogenesis and severity of AF? · Does any kind of PA modify EAT volumes? · Does PA improve outcomes in patients with AF who have undergone PVICA? Methods An umbrella review format was adopted with eligible studies from PubMed, EMBASE, the Cochrane Central Register of controlled trials (CENTRAL), Ovid MEDLINE, CINAHL, and Scopus and registered on Prospero. All results were reported adhering to Preferred Reporting items for Systematic Reviews and Meta-Analysis (PRISMA). Quality assessment evaluation involved the AMSTAR 2 tool and risk of bias evaluated using the ROBIS tool. No ethical considerations were identified for this review. Results Ten reviews were eligible for inclusion in the analysis. Five examined the relationship between EAT and AF occurrence, three examined EAT modifications with PA and two examined the effect of PA on AF outcomes. The quality of the studies was high, with a low risk of bias. Increased EAT volumes were associated with a large effect size for the development of AF Hedges’ g=0.86[0.79,0.92] for Total EAT volume and g=1.31[1.16,1.47] for Left Atrial (LA) EAT volume, and AF severity also had a large effect size for both Total and LA EAT volumes with g=0.87[0.71,1.02] and 0.99[0.69,1.3] respectively. EAT also showed a large effect on recurrence of AF post PVICA in both the Total and LA EAT groups 1.15[0.88,1.43] and 0.92[0.65,1.2]. The overall impact of PA showed a small to medium effect in reducing EAT volumes g=0.23[0,0.46]. Despite this PA was shown to significantly improve outcomes in reducing AF frequency, duration and severity and risk of mortality and serious adverse events in the intervention groups Conclusion Higher levels of EAT are associated with AF after PVICA but the influence of PA is unclear. This review highlights the need for further research evaluating the impact that physical activity has on EAT volume reduction and recurrence of AF post PVICA.

PO-02-164 VALUE OF CARDIONEUROABLATION WITH VAGAL DENERVATION CONFIRMED BY VAGUS NERVE STIMULATION ON PULMONARY VEIN ISOLATION FOR ATRIAL FIBRILLATION CATHETER ABLATION

Despite good results, Atrial fibrillation(AF) ablation shows a relatively high recurrence rate. Therefore, we sought to verify whether endocardial denervation by cardioneuroablation(CNA) can change the AF recurrence post-pulmonary vein isolation(PVI). To compare the long-term AF recurrence post-PVI versus PVI plus vagal denervation (PVI+CNA) by CNA with vagal denervation confirmation by extracardiac vagal stimulation(ECVS). Case-control study of 127 patients, 104(81.9%) males, 53.7±12 years-old, with paroxysmal 71(55.9%) or persistent 56(44.1%) symptomatic AF, refractory to medications without cardiopathy, LA=39.8±6.8, EF=0.66±0.55. Two equivalent groups were established: PVI alone (55 cases) and PVI+CNA (72 cases). The ECVS was performed by intravenous catheter, near the jugular foramen with 50Hz/50microsec/1V/Kg/up to 70V. Endocardial CNA was biatrial over the four main ganglionated plexus and in the AF-Nests regions tagged by fractionation software. The endpoint of CNA was the elimination of the vagal effect induced by ECVS. PVI was achieved in all cases. ECVS effectively induced a vagal reaction in all PVI+CNA patients, and it was possible to eliminate the vagal effect in 88.9% of cases. In 11.1%, there was a slight residual vagal response. Patients were followed up to 45 months (mean FU=21.4±14.2 and 20.4 ± 14.3 months). Recurrences were 17 in the PVI group, and 4 in the PVI+CNA group: Log-Rank p<0.00, HR:5.38(1.78-16.29,p=0.003). No significant complications occurred. The addition of vagal denervation to PVI, with validation of the vagal denervation by ECVS, significantly increased the success rate of the PVI with a marked reduction in AF relapses without increasing complications.

Amplified sinus-P-wave analysis predicts outcomes of cryoballoon ablation in patients with persistent and long-standing persistent atrial fibrillation: A multicentre study.

Outcomes of catheter ablation for non-paroxysmal atrial fibrillation (AF) remain suboptimal. Non-invasive stratification of patients based on the presence of atrial cardiomyopathy (ACM) could allow to identify the best responders to pulmonary vein isolation (PVI). Observational multicentre retrospective study in patients undergoing cryoballoon-PVI for non-paroxysmal AF. The duration of amplified P-wave (APW) was measured from a digitally recorded 12-lead electrocardiogram during the procedure. If patients were in AF, direct-current cardioversion was performed to allow APW measurement in sinus rhythm. An APW cut-off of 150 ms was used to identify patients with significant ACM. We assessed freedom from arrhythmia recurrence at long-term follow-up in patients with APW ≥ 150 ms vs. APW < 150 ms. We included 295 patients (mean age 62.3 ± 10.6), of whom 193 (65.4%) suffered from persistent AF and the remaining 102 (34.6%) from long-standing persistent AF. One-hundred-forty-two patients (50.2%) experienced arrhythmia recurrence during a mean follow-up of 793 ± 604 days. Patients with APW ≥ 150 ms had a significantly higher recurrence rate post ablation compared to those with APW < 150 ms (57.0% vs. 41.6%; log-rank p < 0.001). On a multivariable Cox-regression analysis, APW≥150 ms was the only independent predictor of arrhythmia recurrence post ablation (HR 2.03 CI95% 1.28-3.21; p = 0.002). APW duration predicts arrhythmia recurrence post cryoballoon-PVI in persistent and long-standing persistent AF. An APW cut-off of 150 ms allows to identify patients with significant ACM who have worse outcomes post PVI. Analysis of APW represents an easy, non-invasive and highly reproducible diagnostic tool which allows to identify patients who are the most likely to benefit from PVI-only approach.

The Effect of Colchicine on Atrial Fibrillation: A Systematic Review and Meta-Analysis.

Colchicine is a potent anti-inflammatory agentwhose benefits have been explored for various conditions, including atrial fibrillation (AF). In this article, we tried to understand why colchicine might be beneficial in AF and reviewed various studies that looked at the effect of colchicine against AF. We followed the PRISMA algorithm and undertook a literature search to identify studies with control groups that looked at the effect of colchicine against AF and conducted a meta-analysis. We identified six studies on post-cardiac surgical patients, three on post-pulmonary vein isolation (PVI)/ablation patients, and two on coronary artery disease. In patients who underwent cardiac surgery, we found that colchicine is beneficial against postoperative atrial fibrillation (POAF) with a relative risk (RR) of 0.70 (95% CI of 0.58 to 0.84) and a p-value of 0.0001. We also found that in patients who underwent PVI/ablation, colchicine is beneficial in decreasing AF recurrence over three months with an RR of 0.57 (95% CI of 0.39 to 0.83) and a p-value of 0.0032 and over 12 months follow-up with an RR of 0.58 (95% CI of 0.42 - 0.80) and a p-value of 0.0008. Our meta-analysis showed that in patients with coronary artery disease, colchicine had no significant benefit in decreasing the incidence of AF with a hazard ratio (HR) of 0.86 (95% CI of 0.69 - 1.06) and a p-value of 0.16. From this study, we conclude that colchicine may be beneficial for decreasing the incidence of AF in post-cardiac surgery patients and post-PVI/ablation patients. It may not decrease the incidence of AF in patients with coronary artery disease.

Colchicine for Prevention of Post-Cardiac Surgery and Post-Pulmonary Vein Isolation Atrial Fibrillation: A Meta-Analysis.

Post-cardiac procedure atrial fibrillation (PCP-AF) is a significant medical problem. Inflammation is one of the key factors in the pathogenesis of PCP-AF. As a classical anti-inflammatory drug, colchicine may prevent the occurrence of PCP-AF. This meta-analysis of 12 randomized controlled trials (RCTs) analyzed the feasibility and safety of colchicine for the prevention of PCP-AF. PubMed, EMBASE, Web of Science, the Cochrane Library, and Google Scholar were retrieved for RCTs on the efficacy of colchicine in preventing atrial fibrillation. The primary endpoint was the diagnosis of PCP-AF, which includes cardiac surgery or pulmonary vein isolation. Evaluation was performed with estimated odds ratios (OR) and 95% confidence intervals (CI). In this meta-analysis, 12 RCTs were selected and a total of 2297 patients were included. Colchicine therapy was associated with a reduced incidence of PCP-AF both in post-cardiac surgery (OR: 0.62; 95% CI: 0.49-0.78, p 0.0001, = 0%), and in post-pulmonary vein isolation (OR: 0.43; 95% CI: 0.30-0.62, p 0.0001, = 0%). Colchicine therapy was associated with increased side effects (OR: 2.81; 95% CI: 1.96-4.03, p 0.00001, = 26%). Colchicine can effectively prevent post-cardiac operative atrial fibrillation and relapse of atrial fibrillation after pulmonary vein isolation (PVI). However, colchicine can also increase the incidence of side effects, mainly gastrointestinal adverse events. More studies are needed to find a more appropriate treatment dose and time.

Dyspnea Post Pulmonary Vein Isolation Ablation

Phrenic nerve injury is considered a rare complication of pulmonary vein isolation ablation procedure that is used to treat refractory paroxysmal atrial fibrillation and has been reported in different settings in literature. In this case report, we discuss a case presented with dyspnea, cough, headaches, fatigue, and palpitation five months post pulmonary vein isolation ablation. This case has a medical history of several comorbidities that may contribute to the etiology of the above symptoms. Therefore, the prolonged presentation, late onset of symptoms, and multiple cofactors could be assumed to contribute to patient’s etiology of symptoms attributed to the challenge of the diagnosis. However, one should always keep phrenic nerve injury as a differential when dealing with post pulmonary vein isolation ablation dyspnea or exacerbation of co-existing respiratory symptoms, even when facing delayed presentations of symptoms.

Abstract 9757: Real World Experience With Anticoagulation in Atrial Fibrillation Patients After Pulmonary Vein Isolation: Associations With Cha 2 Ds 2 -vasc Score, Sex and Maintenance of Sinus Rhythm

Background: Guidelines recommend using the CHA 2 DS 2 -VASc score to determine anticoagulation decisions in atrial fibrillation (AF) patients, including those who undergo pulmonary vein isolation (PVI), however this may not consistently occur in the real-world setting because of other clinical factors. We sought to evaluate the anticoagulation prescription patterns in AF patients 1 year PVI at our institution. Methods: Consecutive AF patients undergoing PVI in our prospective registry during 2014-2018 who were alive at 1-year post-PVI were studied. Anticoagulation prescription rates at this time-point were adjudicated, and correlated to CHA 2 DS 2 -VASc score, sex and maintenance of normal sinus rhythm (NSR) at 1 year. Results: Amongst 4596 patients undergoing PVI, mean age was 64.1±10.0 years, 3308 (71.2%) were male, and based on CHA 2 DS 2 -VASc Score anticoagulation was not indicated, can be considered and indicated in 872 (19.0%), 1183 (25.7%) and 2541 (55.3%) patients respectively. At 1-year after PVI, 3504 (76.2%) patients were on anticoagulation, and 792 (17.2%) had recurrence of AF. Anticoagulation rates by sex, CHA 2 DS 2 -VASc Score category and NSR at 1-year after PVI are illustrated in the Figure. Anticoagulation was continued in over half of AF patients without classic CHA 2 DS 2 -VASc indication particularly in those with AF recurrence and women, while they were mildly under-prescribed in those with indication, especially for those without AF recurrence and men. Conclusion: In a large real world cohort of patients post PVI, anticoagulation is prescribed independent of CHA 2 DS 2 -VASc score, and is affected by both sex and NSR status. Factors determining continuous anticoagulation after successful PVI may include parameters not covered in the CHA 2 DS 2 -VASc score such as return of atrial mechanical function on echocardiography, valve disease or extra-cardiac pathologies.

Absence of atrial fibrillation in the blanking period following cryoballoon pulmonary vein isolation – does it always portend a good prognosis?

Abstract Background Cryoballoon (CB) pulmonary vein isolation (PVI) is an accepted method for ablation in patients with paroxysmal and persistent atrial fibrillation (PAF, PeAF). Freedom from AF in the blanking period (BP), conventionally defined as the first 3-months post-PVI, has been associated with the best long-term outcomes. However, the influence of antiarrhythmic drugs (AADs) during the BP on long-term outcomes is not well understood. Objective To compare long-term outcomes between patients who were and were not on an AAD prior to ablation and remained free from AF during the 3-month BP post CB PVI. Methods We enrolled consecutive AF patients undergoing CB PVI; all pts had an implantable loop recorder (ILR). No patient had any AF in the first 90 days post CB PVI. We divided the patients into three groups: (1) never had exposure to an AAD; (2) were intolerant to/failed AAD and thus were not taking an AAD at time of ablation; and (3) were on AAD at time of ablation. In the latter group, every effort was made to stop the AAD before the end of the BP. Results The cohort included 96 pts (66±10 years; 60 [63%] male; 55 [57%] PAF; CHA2DS2-VASc 2.5±1.4). There were 23 (24%) patients in group 1, 13 (14%) patients in group 2, and 60 (63%) pts in group 3. Patients in group 3 were more likely to have PeAF; AADs were stopped at a median of 36 days IQR (27, 91) in this group. Patients were followed for 1-year during which time 28 (29%) patients had recurrent AF (despite having no AF during the BP). The best outcome was seen in patients who never used an AAD; the worst outcome was seen in patients who were on an AAD at time of ablation (Figure 1). Conclusion Our data show that absence of AF during a 3-month post CB PVI BP alone does not guarantee good-long term outcome, unless the patient was never treated with an AAD. In contrast, in patients ablated while taking an AAD, recurrent AF was observed in 37% even though they were completely AF-free during the BP. Funding Acknowledgement Type of funding sources: None.

Pulsed-field ablation-based pulmonary vein isolation: acute safety, efficacy and short-term follow-up in a multi-center real world scenario

PurposePulsed-field ablation (PFA) is a new energy source to achieve pulmonary vein isolation (PVI) by targeted electroporation of cardiomyocytes. Experimental and controlled clinical trial data suggest good efficacy of PFA-based PVI. We aimed to assess efficacy, safety and follow-up of PFA-based PVI in an early adopter routine care setting.MethodsConsecutive patients with symptomatic paroxysmal or persistent atrial fibrillation (AF) underwent PVI using the Farawave® PFA ablation catheter in conjunction with three-dimensional mapping at two German high-volume ablation centers. PVI was achieved by applying 8 PFA applications in each PV.ResultsA total of 138 patients undergoing a first PVI (67 ± 12 years, 66% male, 62% persistent AF) were treated. PVI was achieved in all patients by deploying 4563 applications in 546 PVs (8.4 ± 1.0/PV). Disappearance of PV signals after the first application was demonstrated in 544/546 PVs (99.6%). More than eight PFA applications were performed in 29/546 PVs (6%) following adapted catheter positioning or due to reconnection as assessed during remapping. Mean procedure time was 78 ± 22 min including pre- and post PVI high-density voltage mapping. PFA catheter LA dwell-time was 23 ± 9 min. Total fluoroscopy time and dose area product were 16 ± 7 min and 505 [275;747] cGy*cm2. One pericardial tamponade (0.7%), one transient ST-elevation (0.7%) and three groin complications (2.2%) occurred. 1-year follow-up showed freedom of arrhythmia in 90% in patients with paroxysmal AF (n = 47) and 60% in patients with persistent AF (n = 82, p = 0.015).ConclusionsPFA-based PVI is acutely highly effective and associated with a beneficial safety and low recurrence rate.Graphical abstract

Electrical cardioversion for early recurrences post pulmonary vein isolation

BackgroundTo study the association between timing and success of electrical cardioversion (ECV) for the treatment of early recurrences (ERs) of atrial fibrillation post pulmonary vein isolation (PVI) on long-term rhythm outcome.MethodsData of 133 patients ablated for paroxysmal or persistent atrial fibrillation receiving ECV for ERs, i.e., atrial tachyarrhythmia recurrences within 90 days post ablation were analyzed. During 1-year follow-up, patients were screened for late recurrences (LRs), i.e., recurrences after the blanking period.ResultsIn 114 patients (85.7%), ECV was successful compared to 19 patients (14.3%) with failed ECV. A higher body mass index (odds ratio (OR) 1.19 (95% CI 1.02–1.39), p = 0.029), a lower left ventricular ejection fraction (OR 1.07 (95% CI 0.99–1.15), p = 0.079), and performance of ECV > 7 days from ER onset (OR 2.99 (95% CI 1.01–8.87), p = 0.048) remained independently associated with ECV failure. During 1-year follow-up, the rate of LR was significantly higher among patients with failed ECV as compared to patients with successful ECV (hazard ratio (HR) 3.00 (95% CI, 1.79–5.03), p < 0.001). Patients with ECV performed > 7 days from ER onset had a significantly higher risk of developing LR as compared to patients with ECV performed within ≤ 7 days from ER onset (HR 1.73 (95% CI 1.15–2.62), p = 0.009). Performance of ECV > 7 days from ER onset (HR 1.76 (95% CI 1.16–2.67), p = 0.008) and failed ECV (HR 3.32 (95% CI 1.96–5.64), p < 0.001) remained independently associated with LR.ConclusionsA failed ECV and performance of ECV > 7 days from ER onset were independently associated with LR.

The impact of atrial fibrillation burden early post cryoballoon pulmonary vein isolation on long-term freedom from recurrent atrial fibrillation

Abstract Funding Acknowledgements Type of funding sources: None. Background Pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) ablation. A three-month blanking period (BP) is commonly used in clinical trials and practice. Early recurrence of AF portends worse ablation long-term outcome; however, the utility of using AF burden (AFB) early post cryoballoon (CB) PVI to predict long-term outcome is unknown. Purpose To determine, using ECG data acquired by an implantable loop recorder (ILR), the relationship between post-ablation AFB and long-term freedom from AF. Methods We enrolled consecutive patients with AF who had CB PVI and an ILR. We determined the monthly AFB for the first 3 months post CB PVI and assessed the relationship between AFB and 1-year freedom from AF. We defined 4 distinct AFB groups: (1) 0%, (2) &amp;gt; 0-0.1%, (3) &amp;gt; 0.1-0.5%, and (4) &amp;gt; 0.5%. Results There were 210 patients (66 ± 9 years; 138 [66%] male; 116 [55%] paroxysmal AF; CHA2DS2-VASc 2.5 ± 1.6). Following a 3-month BP, 101 (48%) patients had a recurrence of AF at 160 ± 86 days post-ablation. An AFB of &amp;gt; 0% over the first 3 months predicted AF recurrence (p &amp;lt; 0.0001, Figure 1). Patients with &amp;gt; 0.5% AF burden after 1st month and any AF after 2nd month post CB PVI have a very high long-term AF recurrence rate (Figure 2). Conclusion The best long term outcome post CB PVI is seen in pts who have no AF in the first 3 months post ablation. An AFB &amp;gt;0.5% after the first month and any AF after the second month portend ablation failure. These data define a clinical utility of using AFB to risk stratify patients post CB PVI.

Application of dynamic display technology to identify gaps after pulmonary vein isolation in catheter ablation of atrial fibrillation

BackgroundThe identification of post pulmonary vein isolation (PVI) gaps by activation and voltage maps is time-consuming. This study aimed to investigate the characteristics, efficiency and accuracy of LiveView dynamic display module (EnSite™ Dynamic Display; Abbott, Abbott Park, IL, USA) in unmasking post PVI gaps and conduction block line. MethodTwenty four patients with paroxysmal atrial fibrillation (PAF) who failed to achieve first-pass PVI or with recurrent PAF were enrolled. Ninety-six pulmonary veins (PVs) were evaluated, and gaps were identified in 25 (26.0%) PVs. The gap location was confirmed by activation and propagation maps; 110 frames on gaps and 118 frames on block lines were analyzed by using LiveView module. We defined isochronal crowding in the local activation time (LAT) mode as three colors between two adjacent electrodes. Each frame was classified as with or without isochronal crowding in LAT mode and one/continuous color or isochronal discontinuity in reentrant mode. The gray color inside the PVs was considered to represent conduction block. ResultThe isochronal crowding could be found on both gap and block line in LAT mode, whereas isochronal discontinuity only presented on the block line in reentrant mode. The sensitivity and specificity of isochronal discontinuity or gray color in reentrant mode to identify block line were 61.0% and 100%, respectively. The sensitivity and specificity of isochronal crowding or gray color in LAT mode to identify block line were 71.2% and 71.8%, respectively. ConclusionReentrant mode in LiveView module is very specific in identifying block lines. We proposed an efficient, practical algorithm to differentiate the block line from PV gaps.

The Incidence, Electrophysiological Characteristics and Ablation Outcome of Left Atrial Tachycardias after Pulmonary Vein Isolation Using Three Different Ablation Technologies.

Background: Left atrial tachycardias (LAT) are a well-known outcome of pulmonary vein isolation (PVI). Few data are available on whether the catheter used to perform PVI influences the incidence, as well as the characteristics of post PVI LAT. We present data on LAT following PVI by the following three ablation technologies: (1) phased multi-electrode radiofrequency catheter (PVAC), (2) irrigated single-tip catheter (iRF), and (3) cryoballoon ablation. Methods: Using a prospectively designed single-center database, we analyzed 650 patients (300 iRF, 150 PVAC, and 200 cryoballoon) with paroxysmal (n = 401) and persistent atrial fibrillation (AF), who underwent their first PVI at our center. Results: The three populations were comparable in their baseline characteristics; however, the cryoballoon group comprised a higher percentage of patients with persistent AF (p = 0.05). The LAT rates were 3.7% in the iRF group (mean follow-up 22 ± 14 months), 0.7% in the PVAC group (mean follow-up 21 ± 14 months), and 4% in the cryoballoon group (mean follow-up 15 ± 8 months). The predominant mechanism of LAT was macro-reentrant tachycardia. Reconnection of at least one pulmonary vein was observed in 87% of the patients who underwent 3D mapping. No predictors for LAT occurrence were identified. Conclusion: The occurrence of LAT post PVI is rare; the predominant mechanism was macro-reentrant tachycardia. Reconnection of at least one pulmonary vein was observed in nearly all the LAT patients. In our retrospective analysis, the lowest rate of LAT was observed with the PVAC. No predictors for LAT occurrence were identified.

Identification of Circumferential Pulmonary Vein Isolation Gaps and Critical Atrial Substrate From HD Grid Maps in Atrial Fibrillation Patients: Insights From Omnipolar Technology

Identification of Circumferential Pulmonary Vein Isolation Gaps and Critical Atrial Substrate From HD Grid Maps in Atrial Fibrillation Patients: Insights From Omnipolar Technology

Late gadolinium enhancement-MRI determines definite lesion formation most accurately at 3 months post ablation compared to later time points.

Neither the long-term development of ablation lesions nor the capability of late gadolinium enhancement (LGE)-MRI to detect ablation-induced fibrosis at late stages of scar formation have been defined. We sought to assess the development of atrial ablation lesions over time using LGE-MRI and invasive electroanatomical mapping (EAM). Ablation lesions and total atrial fibrosis were assessed in serial LGE-MRI scans 3 months and >12 months post pulmonary vein (PV) isolation. High-density EAM performed in subsequent repeat ablation procedures served as a reference. Serial LGE-MRI of 22 patients were analyzed retrospectively. The PV encircling ablation lines displayed an average LGE, indicative of ablation-induced fibrosis, of 91.7% ± 7.0% of the circumference at 3 months, but only 62.8% ± 25.0% at a median of 28 months post ablation (p<0.0001). EAM performed in 18 patients undergoing a subsequent repeat procedure revealed that the consistent decrease in LGE over time was owed to a reduced detectability of ablation-induced fibrosis by LGE-MRI at time-points>12 months post ablation. Accordingly, the agreement with EAM regarding detection of ablation-induced fibrosis and functional gaps was good for the LGE-MRI at 3 months (κ .74; p<.0001), but only weak for the LGE-MRI at 28 months post-ablation (κ .29; p<.0001). While non-invasive lesion assessment with LGE-MRI 3 months post ablation provides accurate guidance for future redo-procedures, detectability of atrial ablation lesions appears to decrease over time. Thus, it should be considered to perform LGE-MRI 3 months post-ablation rather than at later time-points>12 months post ablation, like for example, prior to a planned redo-ablation procedure.

Does use of an antiarrhythmic drug prior to cryoballoon pulmonary vein isolation impact the duration of the post-ablation blanking period?

Abstract Background At time of cryoballoon (CB) pulmonary vein isolation (PVI), some patients with atrial fibrillation (AF) are on an antiarrhythmic drug (AAD) while others are not. The impact of AAD use at time of CB PVI on the duration of post-ablation blanking period (BP) is unknown. Objective To determine whether the optimal BP duration differs between pts who were and were not taking an AAD at time of CB PVI. Methods We enrolled consecutive pts with AF who had initial CB PVI; all pts had an implantable loop recorder (ILR). We prospectively followed all pts and determined the time to last AF episode during the 90-day post-PVI BP. This was then correlated with likelihood of having an AF recurrence between 3–12 months post-PVI. Results The cohort included 165 pts (66±9 years; 99 [60%] male; 91 [55%] PAF; CHA2DS2-VASc 2.7±1.6). An AAD was being used at some point prior to ablation in 120 (73%) pts. An AAD was being used at time of CB PVI in 92 (77%) of these 120 pts; this was stopped at a median of 80 [36, 105] days post-PVI. We defined 4 distinct groups: (1) no AF in 90-day BP (n=75 [45%]); (2) last AF within 30 days of PVI (n=32 [19%]); (3) last AF within 60 days of PVI (n=17 [10%]); and (4) last AF within 90 days of PVI (n=41 [25%]). Patients not exposed to an AAD prior to CB PVI had significantly lower likelihood of having no AF in the first 90-days post ablation (p=0.004, Figure). In contrast, if AF was observed post-ablation, as time from ablation to recurrence increased, so did likelihood of long-term failure from ablation (Figure); this relationship was not impacted by use of an AAD. Conclusion The best long-term outcomes post CB PVI are seen in pts who had no prior exposure to an AAD and had no AF within the first 90 days of ablation. Subsequently, as the time from ablation to AF recurrence increased within the 90-day BP, so did likelihood of recurrent AF during long-term follow-up, irrespective of whether an AAD was or was not used. Funding Acknowledgement Type of funding sources: None.

Cardiac Sympathetic Activity and Rhythm Control Following Pulmonary Vein Isolation in Patients with Paroxysmal Atrial Fibrillation-A Prospective 123I-mIBG-SPECT/CT Imaging Study.

Background: Pulmonary vein isolation (PVI) and antiarrhythmic drug therapy are established treatment strategies to preserve sinus rhythm in atrial fibrillation (AF). However, the efficacy of both interventional and pharmaceutical therapy is still limited. Solid evidence suggests an important role of the cardiac sympathetic nervous system in AF. In this blinded, prospective observational study, we studied left ventricular cardiac sympathetic activity in patients treated with PVI and with antiarrhythmic drugs. Prospectively, Iodine-123-benzyl-guanidine single photon emission computer tomography (123I-mIBG-SPECT) was performed in a total of 23 patients with paroxysmal AF, who underwent PVI (n = 20) or received antiarrhythmic drug therapy only (n = 3), respectively. 123I-mIBG planar and SPECT/CT scans were performed before and 4 to 8 weeks after PVI (or initiation of drug therapy, respectively). For semiquantitative SPECT image analysis, attenuation-corrected early/late images were analyzed. Quantitative SPECT analysis was performed using the AHA 17-segment model of the left ventricle. Results: PVI with point-by-point radiofrequency ablation led to a significantly (p < 0.05) higher visual sympathetic innervation defect score when comparing pre-and post PVI. Newly emerging innervation deficits post PVI were localized predominantly in the inferior lateral wall. These findings were corroborated by semiquantitative SPECT analysis identifying inferolateral segments with a reduced tracer uptake in comparison to SPECT before PVI. Following PVI, patients with an AF relapse showed a different sympathetic innervation pattern compared to patients with sufficient rhythm control. Conclusions: PVI results in novel defects of cardiac sympathetic innervation. Differences in cardiac sympathetic innervation remodelling following PVI suggest an important role of the cardiac autonomous nervous system in the maintenance of sinus rhythm following PVI.

B-PO05-096 USING REENTRANT MODE IN A REAL-TIME DYNAMIC SOFTWARE (LIVEVIEW) IN IDENTIFYING PV GAPS AND CONDUCTION BLOCKS DURING PV ISOLATION

The identification of post pulmonary vein isolation (PVI) gap by traditional activation and voltage maps are time-consuming. To investigate the characteristics, efficiency and accuracy of LiveView, a novel dynamic software, in identifying the post PVI gaps and block lines. Patients with PAF who failed to achieve first-pass PVI and with recurrent PAF were enrolled. The gap location was confirmed by activation and propagation maps. Of 25 PVs with gaps, 110 frames on gaps and 124 frames on conduction block lines were analyzed by using LiveView (EnSiteTM Dynamic Display). We defined isochronal crowding in the LAT mode as 3 colors between 2 adjacent electrodes. Each frame was classified as with or without isochronal crowding in LAT mode and one color or continuous color or isochronal discontinuity in reentrant mode. The gray color seen inside the pulmonary veins was considered to represent conduction block. Presentations of gap and block line in LiveView are shown in table 1. LAT mode demonstrated isochronal crowding on both the gap and block line, but reentrant mode showed isochronal discontinuity only on the block line (figure 1A). The sensitivity and specificity of isochronal discontinuity or gray color in reentrant mode to identify block line were 56.45% and 100%, respectively. The sensitivity and specificity of isochronal crowding or gray color in LAT mode to identify block line were 50.8% and 64.5%, respectively. Reentrant mode in LiveView is more accurate than LAT mode in identifying block lines at PV. We proposed an efficient, practical algorithm to differentiate the block line from PV gaps during AF ablation procedure (Figure 1B).