Left Atrial Appendage Isolation Research Articles

Ablation Strategies for Repeat Procedures in Atrial Fibrillation Recurrences Despite Durable Pulmonary Vein Isolation: The Prospective Randomized ASTRO AF Multicenter Trial.

Ablation strategies for patients with symptomatic atrial fibrillation and isolated pulmonary veins vary and their effects on arrhythmia recurrence remain unclear. A prospective randomized German multicenter trial sought to compare 2 ablation strategies in this patient cohort. Patients with atrial fibrillation despite durable pulmonary vein isolation were randomly assigned at 7 centers to undergo low-voltage area ablation using 3-dimensional mapping and irrigated radiofrequency current ablation (group A) or empirical left atrial appendage isolation (LAAI) using the cryoballoon followed by staged interventional left atrial appendage closure (group B). The primary end point was freedom from atrial tachyarrhythmias between 91 and 365 days after index ablation. The study was powered for superiority of LAAI compared with low-voltage area. Patients (40% women; mean age, 68.8±8 years) with paroxysmal (32%) or persistent atrial fibrillation (68%) were randomized to undergo low-voltage area ablation (n=79) or cryoballoon-guided LAAI (n=82). After a planned interim analysis, enrollment was halted for futility on January 10, 2023. In the LAAI group, 77 of 82 left atrial appendages were successfully isolated with subsequent left atrial appendage closure in 57 patients. Procedure-related complications occurred in 4 (5%) and 11 (13.5%) patients in group A and B, respectively (P=0.10). The median follow-up was 367 days (interquartile range, 359-378). The Kaplan-Meier point estimate for freedom from atrial tachyarrhythmias was 51.7% (CI, 40.9%-65.4%) for group A and 55.5% (CI, 44.4%-69.2%; P=0.8069) for group B. The current study did not detect superiority of cryoballoon-guided LAAI over low-voltage area ablation in patients with atrial fibrillation despite durable PVI. URL: https://www.clinicaltrials.gov; Unique identifier: NCT04056390.

Long-term effects of left atrial appendage isolation in surgical ablation of atrial fibrillation based on lesion set: a multi-centre propensity-score weighted study

BackgroundThis present study aimed to investigate the impact of left atrial appendage (LAA) isolation on adverse clinical outcomes, with a further stratified analysis by biatrial (BA) and left atrial lesion...

Comparison of peri-device sealing and procedural outcome after LAA closure in patients with and without isolated left atrial appendage

Abstract Background Catheter-based electrical isolation of the left atrial appendage (LAA) is increasingly performed in patients with symptomatic atrial fibrillation (AF) not responding to pulmonary vein isolation (PVI). Since the electrically isolated LAA is known to be susceptible to thromboembolism, endovascular LAA occlusion (LAAO) is increasingly being used. Objective We performed a procedural and clinical outcome analysis over 12 months in patients receiving two different LAAO device systems and compared those with versus those without LAA isolation (LAAI). Methods Between 08/2021 and 10/2022 we enrolled 83 consecutive patients (median age 73.2 years; median CHA2DS2-VASc Score 3.0; 51 men [61%]) of whom 59 (71%) had LAAI and 24 (29%) no LAAI. All patients had a least one previous catheter ablation procedure of AF. LAAO was done 6 weeks after the last ablation procedure. The main indication for LAAO was the implementation of electrical LAAI. In the no-LAAI group, all patients had lost persistent LAAI. Implanted devices were Watchman FLXTM (n=30) and LAmbreTM (n=53). Pertinent procedural data, periprocedural complications, as well as peri-device leaks (PDL) at 45 days were assessed according to device type. The composite endpoints (death, TIA/stroke, device thrombus, bleeding) and the clinical impact after switch of anticoagulation therapy were assessed at 12 months follow-up. Results The distribution of LAAI/No LAAI were found in 21[70%]/9 patients treated with the Watchman device and in 38[72%]/15 patients treated with the LAmbre device (p=0.87). PDL on follow-up (f/u) TEE was observed in 13/54 LAAI patients (24%) and 10/23 No-LAAI patients (43%, p=0.089). Leak distribution (<3mm/3-5mm/>5mm/no leak) at f/u was different between LAAI groups (LAAI: 12/1/0/41; No LAAI: 5/4/1/13; p=0.027) but not between device types. The mechanisms of leaks according to device type are listed in Table 1. Procedural complications were observed in 6/59 LAAI patients and 0/24 No-LAAI patients (p=0.11). The composite endpoint of death, stroke, severe bleeding, device-related thrombus and thromboembolism was reached by a total of 2 patients (both LAAI with LAmbre device). In 9/13 LAAI-group patients (69%) with PDL (all <6 mm) the sealing effect was assumed to be incomplete with perfusion of the LAA. Post procedural anticoagulation therapy was switched after the control TEE from NOAC/VKA (8/1) to aspirin alone. None of these patients reached the composite endpoint after 12 months. Conclusions LAAO can be performed safely and efficaciously in patients with LAAI. Compared with patients without LAAI after LAAO, the occurrence of minor leaks, periprocedural complications, and composite endpoint events was not different between the two patient groups. Despite the presence of incomplete sealing with perfusion of LAA in the LAAI group, the switch in post-procedural anticoagulation seems to be safe regarding the composite endpoint after 12 months.Mechanism of PDL of the LAmbre DeviceMechanism of PDL between the LAAO types

Characteristics and incidence of peri-device leaks after left atrial appendage closure in patients with prior electrical isolation of left atrial appendage during catheter ablation

Abstract Background Patients who undergo electrical isolation of left atrial appendage (eLAAi) during atrial fibrillation (AF) ablation have a higher subsequent risk of thromboembolism. In post-ablation patients with eLAAi who undergo mechanical LAA closure (LAAC), there are limited data on imaging and clinical outcomes during follow-up, particularly peri-device leaks (PDLs). Purpose We investigated imaging outcomes on ~1 year follow up transesophageal echocardiography (TEE) for PDL and clinical outcomes in patients who had undergone LAAc after sustaining eLAAi from catheter ablation. Methods We analyzed data from TEEs at ~1 year follow up in patients who had undergone LAAC with either the Watchman or Watchman-FLX device. The images were analyzed for evidence of any discernible PDL which also which also included the absence of thrombosis/obliteration of the distal LAA. "Severe" PDL was categorized as the leak size of >5 mm on follow up TEE imaging. Baseline characteristics, imaging and clinical outcomes were compared with univariate comparison using Fisher’s exact test, between the two subgroups of LAAC patients stratified according to prior h/o eLAAi. Results A total of 532 patients underwent LAAC at our center between 03/2015 and 10/2022, with data available on ~1 year follow-up TEE imaging. Of these, 21 (3.9%) had undergone eLAAi during AF ablation prior to LAAC. At ~1 year follow up TEE imaging, the patients with prior h/o eLAAi had a numerically higher incidence of any PDL (42.9% vs 26.5%, p = 0.09). The incidence of severe PDL was significantly higher in the subgroup of patients with prior eLAAi as compared to patients without prior eLAAi (14.3% vs 3.3%, p = 0.04; Figure). There was no statistically-significant difference in the subsequent risk of thromboembolism between the eLAAi and control subgroups (4.8% vs 6.1%, p = 1.0) over an average follow-up of 577±331 days post-LAAC. Conclusions A prior history of eLAAi during AF ablation was associated with a higher risk of severe PDLs (>5mm) on follow up imaging after LAAC. The finding of severe PDL in the eLAAi subgroup might be attributable to ostial fibrosis as a result of ablation which might affect the LAA endocardial surface interaction with the device fabric. The occurrence of a higher risk of severe PDL in patients with prior eLAAi after LAAC might necessitate PDL closure or resumption of anticoagulation in such patients to mitigate the risk of subsequent thromboembolism.igure showing our study schema and compa

Percutaneous left atrial appendage closure using a novel occlusion device for thromboembolic prevention: 3-year procedural experience

Abstract Background Stroke due to atrial fibrillation has been associated with a high risk of disability and mortality. Percutaneous left atrial appendage (LAA) closure has been established as a treatment strategy for stroke prevention in patients not eligible for oral anticoagulation as well as in patients after electrical isolation of the LAA and subsequent increased risk of thrombus formation. The aim of this study was to evaluate the feasibility and initial experience of LAA closure using a novel nitinol-based, self-expanding system in an unselected patient cohort. Methods and Results One hundred and two patients (39% female, median age 75 [71;80], median CHA2DS2-VASc score 5 [4;6]) underwent LAA closure with the novel system between October 2020 and October 2023. 61/102 (61%) patients underwent previous electrical LAA isolation, 30/102 (29%) patients had high bleeding risk as an indication for LAA closure. Median procedure time was 45 [38;59] minutes and median fluoroscopy time was 10 [7;12] minutes. Successful LAA closure was achieved in all patients, despite different LAA anatomies. Median umbrella and cover disc diameter were 22 [20;24] millimeter and 28 [20;24] millimeter, respectively. Procedure-related adverse events occurred in 2/111 (1.8%) patients. One patient had a vascular complication at the puncture site and another patient had non-hemodynamically significant pericardial effusion. Overall, the patients stayed for a median of 2 [1;4] days in hospital. Conclusion Left atrial appendage closure with a novel nitinol-based, self-expanding system is feasible and safe. LAA isolation was the most common indication for LAA closure at our institution. Further studies are needed, to identify differences and potential advantages of different LAA closure systems.

Efficacy of catheter ablation in patients with persistent atrial fibrillation on chronic ibrutinib therapy

Abstract Background Ibrutinib represents a cornerstone in the management of B-Cells malignancies and chronic lymphatic leukaemia. This drug however was associated with a 5-fold increased risk of developing atrial fibrillation (AF). The consequences of AF in this category of frailty patients such as heart failure may lead to the need of Ibrutinib withdrawal, which is considered a disease modifying therapy. Purpose This study aims to evaluate the safety and efficacy of catheter ablation in managing AF in patients on chronic ibrutinib therapy. Methods this study evaluated 20 consecutive patients from two centres in Italy who developed persistent AF during chronic therapy with Ibrutinib for chronic lymphatic leukaemia or small lymphocytic lymphoma and underwent AF catheter ablation from 2016 to 2020. Antiarrhythmic drugs were withdrawn because of side effects and drug interaction. All receive pulmonary vein (PV) isolation + isolation of left atrial posterior wall (PW) and superior vena cava. A standardized protocol was performed to confirm persistent PVI and elicit any triggers originating from non-PV sites. Ablation of non-PV sites triggering runs of atrial tachyarrhythmias was left to operator's discretion. Exclusion criteria were age<18 years and history of AF before ibrutinib therapy. Patients were monitored for arrhythmia at quarterly office visits, ECGs, 7-day Holter monitoring and event recorders during the first year followed by biannual checkups during the remaining part of the follow-up period. Results 12 patients received PV+PW+SVC isolation plus ablation of non-PV trigger (Group 1) whereas 8 receive only PV+PW+SVC isolation (Group 2). 10 (83,3%) patients in group 1 remained arrhythmia-free without the need for additional antiarrhythmic drugs while only 3 (37,5%) in group 2 maintained sinus rhythms. Non pulmonary triggers were mostly found in left atrial appendage (5/12, 41,6%), coronary sinus (4/12, 33,3%) and crista terminalis (3/12 25%). More than one trigger was found in 4 (33.3) patients. After 22.3 ±3.6 months follow-up, patients with ablation of induced non-PV triggers had a significantly higher arrhythmia control than those whose triggers were not ablated (Chi – square p value: 0.035; Log rank p value: 0.014) (Fig.1). 5 patient that received left atrial appendage isolation underwent a left atrial appendage closure with Watchman device 3 months after atrial fibrillation ablation. Conclusion Catheter ablation in this category of patients seems to be a safe and effective tool for managing atrial fibrillation in patients with persistent AF on chronic ibrutinib therapy; an ablation strategy that includes as a first line therapy non pulmonary vein triggers appears to be an effective approach when compared to pulmonary vein plus posterior wall only. This approach will allow continuation of ibrutinib treatment, which markedly enhances the prognosis and diminishes the risk of adverse cardiovascular events in this patient population.Kaplan-Meier curve showing recurrence-fr

Electrophysiological findings in patients undergoing left atrial appendage occlusion following previous electrical isolation

Abstract Funding Acknowledgements Type of funding sources: None. Background Left atrial appendage electrical isolation (LAA) is an important adjunctive ablation strategy in patients with nonparoxysmal atrial fibrillation. If impaired mechanical function following isolation is observed, long-term oral anticoagulation (OAC) or, as an alternative, LAA occlusion are required. Although focal electrical potentials from the LAA do not result in normalization of appendage mechanical function, they may potentially be a source of arrhythmogenic triggers. Those focal areas might be challenging to ablate after LAA occlusion device implantation. Purpose We sought to report the incidence of focal electrical potentials in patients with a previously isolated LAA and transesophageal echocardiography (TEE) evidence of severely impaired LAA mechanical function undergoing endocardial LAA occlusion. Methods In 124 patients undergoing LAA occlusion following LAA isolation, a circular mapping catheter (CMC) was used before occlusion to document any residual LAA electrical activity. Results At preprocedural TEE, the median LAA contraction velocity was 0.13 m/s (IQR: 0.05-0.19) and was significantly impaired in all patients. Of the 124 patients (mean age: 69±8 years; 71.7% males), 61 (49.2%) did not display any evidence of residual LAA electrical activity. In the remaining 63 (50.8%) patients, residual electrical potentials resulting in LAA reconnection were recorded on the CMC positioned into the appendage. On average, 4.9±1.7 radiofrequency energy applications (45W, mean duration of each RFA: 14.2±3.4s) were required to re-achieve complete isolation. Subsequent appendage occlusion was successful in all patients. No leaks ≥5mm and 3 (2.4%) 3-4mm-leaks were documented at 45day-TEE. Conclusions Focal electrical activity from the LAA was documented in approximately half of our patients. Although focal electrical potentials do not result in normalization of LAA mechanical function, they may potentially act as arrhythmogenic triggers. Since it may be challenging after device implantation, assessment and ablation of those areas should be considered before occlusion device deployment.

PO-05-155 A CASE OF ALCOHOL LEADING TO ISOLATION IN THE ELECTROPHYSIOLOGY LABORATORY

Ligament of Marshall alcohol ablation is a treatment for refractory atrial fibrillation and left atrial flutter. Left atrial appendage (LAA) isolation resulting from LOM ablation has not been described. To describe a case of LOM alcohol ablation which resulted in left atrial appendage isolation and dissociation of a left atrial appendage reentrant atrial flutter from the atria. A middle aged man with a history of atrial fibrillation and multiple left atrial flutters was referred for repeat ablation after multiple prior unsuccessful ablations. He previously underwent surgical MAZE and 3 endocardial ablations including an anterior mitral line and endocardial and epicardial mitral isthmus line without achieving bidirectional block. He had recurrent, symptomatic atrial flutter despite therapy with dofetilide and metoprolol. The patient presented in an atypical flutter. The ligament of Marshall was cannulated and alcohol was sequentially injected for a total of 3.8 mL. After the first alcohol injection, the tachycardia abruptly terminated on the coronary sinus (CS) catheter and sinus rhythm resumed (Figure, blue arrows), though the surface ECG showed ongoing small atrial flutter waves (Figure, red arrows). Subsequent left atrial mapping confirmed that the left atrial appendage (LAA) was isolated from the remaining left and right atrium and remained in atrial flutter (Figure C). Overdrive pacing from a multipolar catheter in the LAA demonstrated a post-pacing interval within 20 ms of the tachycardia-cycle length (Figure C). Adenosine administration resulted in AV block but no alteration in tachycardia cycle-length. These findings were highly suggestive of a reentrant mechanism. Because 3D mapping was limited by dissociated CS and LAA rhythms, manual activation mapping was performed with earliest activation at the anterior superior LAA. RF ablation at this site resulted in atrial flutter slowing and termination. In a patient with LAA flutter and prior anteroseptal and lateral linear endocardial ablation, LOM alcohol ablation may isolate the LAA. This should be recognized when counseling patients and planning procedures.

AB-452675-1 ELECTROPHYSIOLOGICAL FINDINGS DURING REDO PROCEDURES AFTER PULSED FIELD ABLATION USING A PENTASPLINE CATHETER TO TREAT ATRIAL FIBRILLATION IN ROUTINE CLINICAL PRACTIC

Data from clinical trials of pulsed field ablation (PFA) to treat atrial fibrillation (AF) indicate highly-efficient workflow, an excellent safety profile, good clinical outcomes with few AF recurrences. Also strikingly, protocol-directed invasive remapping procedures revealed a high degree of durability of the pulmonary vein isolation (PVI) lesion sets. While quite favorable, PVI durability in carefully-monitored protocols may not translate to day-to-day clinical practice. Assessing durability with routine invasive remapping is not possible in routine clinical practice, but the “electrical status” of the PVs during clinical redo procedures provides compelling insights into the technical efficacy of the index procedure. To evaluate the electrophysiologic findings during redo procedures in AF patients initially treated with PFA. This single-center study included all redo ablations after an index PFA using the pentaspline catheter (Farapulse; BSC Inc.); patients in clinical trials were excluded. During the redo case, all PVs and any other lesions we assessed. Redo ablation was performed using either RF or PF energy, per operator preference. Between April 2021 (time of PFA approval) and Nov 2022, 863 consecutive AF ablations were performed using the pentaspline PFA catheter in our center. Clinically-indicated redo procedures were performed in 28 (3.2%) patients: mean age 66 yrs, 17M/11W, BMI 29, LA size 46 mm, PAF/PerAF 17/11. Mapping revealed reconductions (gaps) in 33 of 110 (30%) PVs (gaps seen in 18 pts). The distribution of the reconnections was slightly higher in the right PVs: RSPV 9, RIPV 11, LSPV 7, LIPV 6, LCPV 2. For other lesions placed during the index procedure, reconduction was observed in: 3 of 6 (50%) pts with mitral lines, 1 of 6 (17%) pts with posterior box, and 2 of 2 (100%) pts with left atrial appendage isolation. In 2 pts with initially paroxysmal AF and durable PVI, peri-mitral flutter was the clinical tachycardia, in 1 patient the symptomatic tachycardia was typical AVNRT. Only a minimal number (3,2%) of 863 patients (outside of those enrolled in clinical trials) after PF ablation of atrial fibrillation using Farapulse system underwent reablation for recurrent atrial tachyarrhythmia in our center. Even after PF ablation, gaps in the pulmonary veins remain the most common finding – 30% of treated veins were not permanently isolated.

PO-03-161 INTRA-PROCEDURAL CROSSOVER OF LEFT ATRIAL APPENDAGE OCCLUSION DEVICES, A SINGLE CENTER EXPERIENCE

Two devices are currently available for percutaneous left atrial appendage occlusion (LAAO), Watchman FLX and Amplatzer Amulet. While in most cases LAAO is achieved by implanting the originally planned device, intra-procedural crossover from one type to the other might be necessary when LAAO is not satisfactory. To evaluate the rate and characteristics of intra-procedural device crossover in LAAO procedure. All successful LAAO procedures performed in our center since October 2021 (Amulet’s FDA approval) are included in the study. Of note, LAAO procedures are performed under fluoroscopic and ultrasound (TEE or ICE) guidance, without formal preprocedural imaging planning. 365 patients (74±9 years; 34% female) underwent LAAO over 12 months. LAAO was successful in all but 1 case, in which the LAA was too large for successful implantation of the originally planned device (Watchman) and crossover was not attempted. In almost all cases (361/364, 99%), the original planned device was implanted successfully achieving complete LAAO (Watchman in 325 patients, Amulet in 34 patients). Intra-procedural device crossover was observed in 4 (1%) patients, all from Watchman to Amulet. In 3 cases, the LAA ostium and proximal LAA were large, leading to deployment of an undercompressed, unstable 35 mm Watchman device: Amulet allowed positioning of the lobe in a more distal, stable location with the disc covering the ostium (Figure, left panel). In 1 case, the LAA was of adequate size, but a proximal ridge (s/p LAA isolation) lead to Watchman deformation (struts’ introversion on one side) once fully deployed, a behavior observed despite multiple recaptures and a device change: with Amulet, the lobe could be placed distally to the ridge with the disc covering the ostium (Figure, right panel). Mean procedural time was 107±3 min, with a mean contrast volume used of 203±70 mL and a mean fluoroscopy time of 15±4 min (yielding to a mean dose of 2070±3107 mGy). There were no procedural-related complications, and all patients were discharged home after overnight observation. Intraprocedural LAAO device crossover is a rare occurrence, usually secondary to unsatisfactory deployment of the originally planned device. To avoid unsuccessful LAAO, operators should be skilled in implantation of both type of devices and be able to switch from one to the other at the time of the index procedure.Tabled 1PatientLAA os max diameterOriginal deviceFinal device131 mm35 mm Watchman FLX31-mm Amplatzer Amulet229 mm35-mm Watchman FLX34-mm Amplatzer Amulet329 mm35-mm Watchman FLX34-mm Amplatzer Amulet421 mm27-mm Watchman FLX22-mm Amplatzer Amulet Open table in a new tab

Incidental left atrial appendage isolation after catheter ablation of persistent atrial fibrillation: Mechanisms and long-term risk of thromboembolism.

Incidental left atrial appendage (LAA) isolation may occur during radiofrequency ablation of persistent atrial fibrillation (AF). The study aims to describe the mechanisms and long-term thromboembolic risk related to incidental LAA isolation. Patients who experienced incidental LAA isolation after AF ablation were included. Culprit sites where ablation resulted in LAA isolation were identified. Thromboembolic risk despite oral anticoagulation (OAC) was compared to that in a propensity-matched control group without LAA isolation. Forty-one patients with LAA isolation, and 82 matched patients without LAA isolation were included. The patient age, ejection fraction, LA diameter, and CHA2 DS2 -VASc score were 64 ± 11 years, 55 ± 12%, 45.0 ± 7 mm and 2.62 ± 1.5, respectively. Culprit sites included the LAA base, mitral isthmus, inferior LA, Bachmann's bundle, coronary sinus, and Marshall vein. After 4.2 ± 3.6 years follow-up, thromboembolism occurred in 7 of 41 patients (17%) with LAA isolation versus 3 of 82 patients (4%) without isolation (log rank p < .009, HR 5.14, 95% CI [1.32-19.94], p = .02). Patients with and without thromboembolism had similar CHA2 DS2 -VASc scores (2.65 ± 1.3 vs. 2.71 ± 0.76, p = .89). Thromboembolism occurred during noncompliance with or temporary discontinuation of OAC in four of the sevenpatients. Incidental LAA isolation may occur during ablation of atrial arrhythmias in the vicinity of, or even at sites remote from the appendage. Patients with incidental LAA isolation had higher rates of thromboembolism compared to patients without isolation. Since thromboembolism may occur despite prescription for OAC, the risks of LAA isolation must be weighed against clinical benefit and appendage occlusion devices should be considered in vulnerable patients.

Left atrial anterolateral linear ablation for biatrial tachycardia via Bachmann's bundle, interatrial septum, and left atrial anterior wall under mitral isthmus block.

Biatrial tachycardia via Bachmann's bundle, interatrial septum, and left atrial anterior wall can be treated by left atrial anterolateral linear ablation without left atrial appendage isolation, even under mitral isthmus block.

Safety and Feasibility of Catheter Ablation Procedures in Patients with Bleeding Disorders.

Aims/Objectives: Patients with bleeding disorders are a rare and complex population in catheter ablation (CA) procedures. The most common types of bleeding disorders are von Willebrand disease (VWD) and hemophilia A (HA). Patients with VWD or HA tend to have a higher risk of bleeding complications compared to other patients. There is a lack of data concerning peri- and postinterventional coagulation treatment. We sought to assess the optimal management of patients with VWD and HA referred for catheter ablation procedures. Methods and Results: In this study, we analyzed patients with VWD or HA undergoing CA procedures at two centers in Germany and Switzerland between 2016 and 2021. Clotting factors were administered in conjunction with hemostaseological recommendations. CA was performed as per the institutional standard. During the procedure, unfractionated heparin (UFH) was given intravenously with respect to the activated clotting time (ACT). Primary endpoints included the feasibility of the procedure, bleeding complications, and thromboembolic events during the procedure. Secondary endpoints included bleeding complications and thromboembolic events up to one year after catheter ablation. A total of seven patients (three VWD Type I, one VWD Type IIa, three HA) underwent 10 catheter ablation procedures (pulmonary vein isolation (PVI): two × radiofrequency (RF), one × laser balloon (LB), one × cryoballoon (CB); PVI + cavotricuspid isthmus (CTI): one × RF; PVI + left atrial appendage isolation (LAAI): one × RF; Premature ventricular contraction (PVC): three × RF; Atrioventricular nodal reentrant tachycardia (AVNRT): one × RF). VWD patients received 2000−3000 IE Wilate i.v. 30 to 45 min prior to ablation. Patients with HA received 2000−3000 IE factor VIII before the procedure. All patients undergoing PVI received UFH (cumulative dose 9000−18,000 IE) with a target ACT of >300 s. All patients after PVI were started on oral anticoagulation (OAC) 12 h after ablation. Two patients received aspirin (acetylsalicylic acid; ASA) for 4 weeks after the ablation of left-sided PVCs. No anticoagulation was prescribed after slow pathway modulation in a case with AVNRT. No bleeding complications or thromboembolic events were reported. During a follow-up of one year, one case of gastrointestinal bleeding occurred following OAC withdrawal after LAA occlusion. Conclusions: After the substitution of clotting factors, catheter ablation in patients with VWD and HA seems to be safe and feasible.

Prevention of Cardioembolic Complications in Patients with Atrial Fibrillation: Efficacy and Safety of Left Atrial Appendage Isolation and Oral Anticoagulants

Aim. To study the outcomes frequency and structure in patients with atrial fibrillation (AF) depending on the cardioembolic events preventing method: left atrial appendage (LAA) isolation, direct oral anticoagulants (DOACs) or warfarin.Material and methods. A prospective observational study included patients with AF and high risk of cardioembolic complications and without contraindications to anticoagulants. Patients who refused long-term oral anticoagulants taking underwent LAA isolation, the rest of the patients received DOACs or warfarin. The observation period was 3 years. Mortality, cardioembolic complications and major bleeding (according to GARFIELD criteria) cumulative incidence was assessed.Results. We included 245 patients: 46 patients were treated with LAA isolation, 100 with warfarin, and 99 with DOACs. Multivariate regression analysis demonstrated a statistically significant advantage of LAA occluder in terms of combined endpoint achieving frequency compared to warfarin (hazard ratio [HR] 3.10; 95% confidence interval [CI] 1.01-9.54; p=0.049), and to DOACs (HR 3.44, 95% CI 1.15-10.29; p=0.027). A similar result was obtained for all-cause mortality (HR 5.24; 95% CI 1.12-24.55; p=0.036 and HR 5.58; 95% CI 1.22-25.49; p=0.027, respectively). There were no significant differences in bleeding rates between the groups.Conclusion. This observational study demonstrates the superiority of LAA isolation as a first-line therapy over DOACs and warfarin in patients with AF and high risk of cardioembolic complications. Randomized trials are required to confirm these observations.

Transesophageal Echocardiography Following Left Atrial Appendage Electrical Isolation: Diagnostic Pitfalls and Clinical Implications.

Following left atrial appendage (LAA) electrical isolation, the decision on whether to continue oral anticoagulation after successful atrial fibrillation ablation is based on the study of its mechanical function on transesophageal echocardiography (TEE). In this cohort, LAA contraction is absent and the incorrect interpretation of emptying flow velocities can lead to unwanted clinical sequelae. One hundred and sixty consecutive TEE exams performed to evaluate the LAA mechanical function following its electrical isolation were reviewed by an experienced operator blinded to the original diagnosis of LAA dysfunction. The rate of diagnostic discrepancy in the assessment LAA dysfunction and its clinical implications were evaluated. Diagnostic discrepancy with misclassification of the LAA mechanical function occurred 36% (58/160) of TEE exams. In most cases (57/58), such discrepancy was observed in the setting of an incorrect original diagnosis of a normal LAA mechanical function despite absent/reduced or inconsistent LAA contraction. This main source of this wrong diagnosis was the wrong interpretation of passive LAA flows (34/57; 60%), followed by failure to identify dissociated firing (15/57; 26%). In rare cases (8/57; 14%), velocities of surrounding structures were interpreted as LAA flow due to misplacement of the pulsed-wave Doppler sample volume. Following LAA isolation, the proportion of patients who experienced a cerebrovascular event while off oral anticoagulation due to the misclassification of their LAA mechanical function was 70% (7/10 [95% CI, 40%-89%]). Underdiagnosis of LAA mechanical dysfunction is common in TEEs performed following LAA electrical isolation, and it is associated with an increased risk of cerebrovascular events owing to oral anticoagulation discontinuation despite absent/reduced LAA contraction. Careful review of the TEE exam by an operator with specific expertise in LAA imaging and familiar with the functional implications of LAA isolation is necessary before interrupting oral anticoagulation in this cohort.

Anatomy of the left atrial appendage for the interventional cardiologist.

Exact knowledge of the anatomy of the left atrial appendage (LAA) is crucial for LAA isolation by catheter ablation and for interventional LAA occlusion in patients with atrial fibrillation. This review outlines the current anatomical understanding of LAA morphology from ostium to distal lobes, myocardial fiber orientation and wall structure, and adjacent structures such as the left upper pulmonary vein with the Coumadin ridge, the circumflex artery with its side branches, the aortic root, pulmonary artery, and the pericardial space. Insight into these details will facilitate these interventions and reduce the risk of complications.

Efficacy and safety of left atrial appendage isolation in addition to pulmonary vein isolation in atrial fibrillation cryoballoon ablation

Abstract Funding Acknowledgements Type of funding sources: None. Background Although pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) ablation, the percentage of patients in which a recurrence is detected is still high. This concern has increased the interest in finding new ablation techniques that could diminish recurrences. Purpose To determine if left atrial (LA) appendage isolation (LAAI) in addition to PVI is a safe procedure and if it entails an improvement in the recurrence of AF. Methods Single-center retrospective study including patients with paroxysmic (PxAF) or persistent (PsAF) AF referred to cryoballoon ablation (CAB), comparing patients in whom LAAI was performed with those in whom only PVI was performed. Results 131 patients (59.9 ± 12.3 years, 65.9% males) were referred to CAB in our center between 2017 and 2021. 103 patients (78.6%) had PxAF and 28 (21.4%) PsAF. Most patients had had AF for at least two years (65.6%), 12.2% between one and two years and 22.2% for less than one year. The median CHA2DS2-VASc score was 1 [0-2] and 72.5% had permanent anticoagulation indication. 90.1% had tried at least one antiarrhythmic drug (AAD) before the procedure (57.3% one AAD, the rest at least two AADs), being amiodarone (46.2%) and flecainide (46.2%) the most commonly used. Cardioversion prior to CAB was performed in 57.3% of patients. The most common anatomy was 4 independent pulmonary veins (81.7%), followed by left common trunk (10.7%). LAAI was performed in 41 patients (31.3%) and it was performed more frequently in patients with PsAF and permanent anticoagulation indication, as well as in hypertense patients with bigger LA diameter (Table 1). The rate of complications was low in both groups, highlighting the absence of periprocedural cardioembolic stroke (CES) and the low rate of CES in the follow-up (2.1%) (median time to the apparition of the CES 27 [20-27] months), with no statically significative differences between LAAI and PVI groups. During the 23 [13-37] months of follow-up, 32 patients (24.4%) had a recurrence after the 3-month blanking period (time to apparition of recurrence of 11 [6-21.75] months). There were no statically significant differences in the recurrences or in the complications between LAAI and PVI groups, neither in PxAF nor in PsAF patients (Table 2), although PxAF patients tended to have less recurrences when LAAI was performed (11.1% vs 25.0%, p=0.175). On the other hand, the 1-year success rate (defined as the absence of recurrence in the 12 months following the blanking period), was 80.2% (out of 96 patients who had at least 15-month follow-up), with no statically significative differences between LAAI and PVI groups (80.8% vs 80%, p=0.933). Conclusions LAAI is a safe procedure with a low rate of complications and no evidence of increased risk of CES in the follow-up. Although LAAI did not entail a lower recurrence rate, it could have a role in selected PxAF patients. Larger studies with longer follow-up are needed to confirm our data.

Assessment of atrial fibrillation catheter ablation outcomes in patients with hypertrophic cardiomyopathy

Abstract Funding Acknowledgements Type of funding sources: None. Background Atrial fibrillation (AF) is a frequent manifestation of hypertrophic cardiomyopathy (HCM) and it is associated with increased risk for thromboembolic events and worsening of heart failure. AF is usually refractory to antiarrhythmic drugs in cases with HCM and catheter ablation may be useful in such patients. Purpose We aimed to evaluate outcomes of both cryoballoon and radiofrequency (RF) AF catheter ablation in patients with HCM. Methods All of the patients with HCM who underwent AF catheter ablation between January 2014 and January 2022 were screened and patients with available follow-up datas were included. Results A total of 44 patients were enrolled. Mean age was 54.2±12.6 years and 45.5% of the patients were female. RF ablation was performed in 23 cases and remaining patients underwent cryoablation. Median follow-up was 42.5 (4-94) months. Baseline characteristics were listed in Table-1. Only pulmonary vein isolation was performed in 25 (56.8 %) patients while additional ablation procedures including left atrial appendage isolation and linear ablation were required in other cases. Periprocedural complications occured in 6 cases. Atrial tachycardia recurrence developed in half of patients and mortality occured in 2 (4.5 %) cases during follow-up (Table-2). Six months recurrence free survival (RFS) rate was 90.9% and 1 year RFS was 86.1% however RFS rate reduced to 58.2 after 3 years follow-up. Atrial tachycardia recurrence rates, complication and mortality rates were similar between the patients who underwent cryoablation and RF ablation. Changes in NYHA class and BNP levels were not significant during follow-up, however EHRA class was distinctly improved (II vs. I; p&amp;lt;0.001). Conclusion Although long term outcomes of AF catheter ablation is not satisfactory; it is effective in short term rhythm control with reasonable complication rates. Recurrence rates are similar between RF and cryoablation.

Hot or cold? Feasibility, safety, and outcome after radiofrequency-guided versus cryoballoon-guided left atrial appendage isolation.

BackgroundLeft atrial appendage (LAA) isolation (LAAI) has been described as an adjunctive ablation strategy for patients with recurrent atrial tachyarrhythmia (ATa).ObjectivesWe compared the clinical impact of persistent durable LAAI between radiofrequency (RF)‐guided wide‐area LAAI and cryoballoon (CB)‐guided ostial LAAI.MethodsConsecutive patients who underwent RF‐ or CB‐guided LAAI were retrospectively analyzed. RF‐guided LAAI was performed by combining linear ablation. CB‐guided LAAI was performed by LAA ostial ablation. Following LAAI, the patients underwent an invasive remapping study. LAA closure was conducted if persistent durability was confirmed. The procedural data, LAAI durability, and ATa recurrence were assessed.ResultsA total of 260 patients (RF: n = 201; CB: n = 59) undergoing LAAI were identified. The acute rate of procedural LAAI was higher in the CB group (CB:94.9% vs. RF:82.6%, p = .02) with a lower pericardial effusion incidence (CB:0% vs. RF:7.5%, p = .03). The 6‐week durable LAAI was similar between the two groups (RF:78.3% vs. CB:66.0%, p = .103). During follow‐up, one gastrointestinal bleeding and four stroke events including one subsequent intracranial bleeding leading to death occurred in the RF group, while one gastrointestinal bleeding occurred in the CB group.The 1‐year ATa recurrence‐free rate was higher in patients with durable LAAI following RF‐guided LAAI (RF:76.3% vs. CB:56.7%, p = .0017). Multivariate analysis revealed RF‐guided LAAI as a predictor of freedom from ATa recurrence (HR: 0.478, 95%CI: 0.336–0.823, p = .017).ConclusionsLAAI can be more readily and safely achieved by CB‐guided ostial ablation. In patients with confirmed LAAI, however, the freedom from ATa recurrence was higher after RF‐guided wide‐area isolation.

Case report of the leftatrial appendage perforation during endovascular occlusion

In patients with ischemic stroke more than 17 % have atrial fibrillation. Oral anticoagulant therapy is the main strategy for embolism prevention in patients with atrial fibrillation. In the presence of contraindications, an alternative to anticoagulant therapy is isolation of the left atrial appendage. The use of the left atrial appendage occluder is comparable in effectiveness to the prevention of ischemic stroke using anticoagulant therapy. However, possible complications arising from device implantation remain a limitation to the spread of this method. The article presents a clinical observation of a 55-year-old patient who was admitted to the hospital for a planned intervention — endovascular implantation of the Watchman device (Boston Scientific, USA). The development of atrial fibrillation was induced by acute myocardial infarction in 2016. In 2019, the patient underwent ischemic stroke in the territory of the right middle cerebral artery. The indication for implantation was recurrent gastroduodenal bleeding while taking oral anticoagulants. During the implantation stage, the delivery system was dislocated into the pericardial cavity. In connection with the frolicking complication, a decision was made to drain the pericardium with repositioning and subsequent implantation of the Watchman to close the left atrial appendage defect. Despite the frolic complication, left atrial appendage isolation was achieved. This prevented the development of massive hemopericardium and cardiac tamponade. The patient fully returned to normal life and self-care, the modified Rankin score was 190 days after the surgery. During the 10-month follow-up, the patient did not experience cardiovascular events and major bleeding, which indirectly indicates the effectiveness of left atrial appendage occlusion, despite the developed complication.