Deflectable Sheath Research Articles

Catheter ablation of atrial fibrillation in a patient with interruption of the inferior vena cava complicated with persistent left superior vena cava.

A 55-year-old woman of I-IVC complicated with PLSVC underwent catheter ablation for atrial fibrillation through right jugular vein access. TSP was achieved by electrocautery and the J-tip guidewire with the help of deflectable sheath and ICE. After PVI, the CS-PLSVC and LA-PLSVC connections were ablated within PLSVC.

Need an endomyocardial biopsy? Call your electrophysiology team

Abstract Introduction With significant advances in targeted chemotherapeutic options for soft tissue tumours, obtaining a tissue diagnosis is more important than ever. Primary and secondary cardiac tumours are rare [1] and endomyocardial biopsy of these tumours has been sparsely reported [2-9]. Advanced tools in cardiac electrophysiology happen to lend themselves well to cardiac tumour biopsy. Our electrophysiology (EP) guided endomyocardial biopsy (EMB) service includes electrophysiologists, cardio-oncology specialists, cardiac imaging specialists, oncologists, and pathologists. For the last 9 years all targeted endomyocardial biopsies in our tertiary institution have been undertaken by our EP guided EMB service with extensive experience in electroanatomical mapping (EAM), visualisable sheaths and integrated intracardiac echography (ICE). We report the findings. Methods We performed a retrospective review of all cases referred to the EP guided endomyocardial biopsy service at our centre and identified those with attempts to biopsy a cardiac mass. We describe the incorporation of advanced electrophysiology techniques utilised by the service. Specifically, the use of intracardiac echocardiography integrated into an electro-anatomical mapping system and bioptome delivery via a visualisable, deflectable sheath. This allows for the real time 3D visualisation of the target mass, surrounding anatomy and position of the bioptome during biopsy. Results Of 38 patients who underwent targeted biopsy at our centre, a total of 8 patients (5 female; mean ± SD age 54 ± 21 years) were referred for cardiac tumour biopsy, undergoing a total of 9 procedures (mean ± SD duration 116 ± 21 mins). Table 1 details the patient’s pertinent history and underlying pathology, the tumour site, possible alternative biopsy sites, a summary of techniques and technologies utilised and the eventual diagnosis. In 100% of cases, tissue was sampled from the desired location, though in two patients the histological result was inconclusive due the retrieval of necrotic tissue or fibrotic tissue only. This translated into a definitive histopathological diagnosis in 75% of patients. One patient experienced a transient right bundle branch block during the procedure, in all others the procedures were uncomplicated. Image 1 exemplifies some of the cases with pre-procedure imaging results and intra-procedural views from both ICE and the EAM. Conclusion In this study, our approach to utilising the combination of intracardiac echocardiography integrated into an electro-anatomical mapping system and bioptome delivery via a visualisable, deflectable sheath appears safe, and provides unparalleled accuracy in endomyocardial sampling of cardiac tumours.Table 1Image 1

Dry suction water seal system for management of pericardial fluid during epicardial ablation.

Epicardial ablation is an important approach in the management of patients with complex ventricular arrhythmias. Irrigated ablation catheters present a challenge in this potential space due to fluid accumulation that can cause hemodynamic compromise, requiring frequent manual fluid aspiration. In this series, we report our initial experience with the use of a dry suction water seal system for pericardial fluid management during epicardial ablation. Consecutive patients undergoing epicardial ventricular tachycardia (VT) ablation at a single center were included. All patients underwent epicardial access via a subxiphoid approach with a single operator. A deflectable sheath was advanced into the pericardial space, and the side port was attached to a dry suction water seal system attached to wall suction at -20 mmHg. Procedural information including patient characteristics, outcomes, and adverse events. After a period of initial experience, pericardial fluid infusion and aspiration volumes were recorded. Eleven patients were included in this series. All patients underwent epicardial ablation with complete success achieved in 8 of the 11 patients and partial success in the remaining patients. Pericardial fluid intake ranging from 485 to 3050 mL with aspiration of 350-3050 mL using the dry suction water seal system. No adverse events occurred. Dry suction water seal drainage systems can provide a safe strategy for efficient pericardial fluid management during epicardial VT ablation, potentially shortening procedure duration.

Dynamical improvement after rescue balloon angioplasty for pulmonary vein occlusion complicated with radiofrequency catheter ablation.

A 71-year-old man was referred to our hospital owing to hemoptysis. Pulmonary vein (PV) isolation by radiofrequency ablation with atrial fibrillation was performed twice 3 years prior. Bronchoscopy revealed a left bronchial hemorrhage (Figure A). Multidetector computed tomography (CT) revealed left superior and inferior PV (LIPV) occlusion (Figure B). There was reduced perfusion to the left upper and inferior lobes in Tc-99m macroaggregated albumin (MAA) (Figure D). First, the pulmonary artery pressure (PAP) was measured as 59/30 (42) mmHg, and PA angiography showed LIPV occlusion (Figure F, Supplementary data online, Movie S1). After a transseptal puncture, a 5 Fr multipurpose catheter was inserted through a deflectable sheath (Agilis, Abbott) near the LIPV occlusion site. A 0.035 in Radifocus guidewire and 5 Fr multipurpose catheter were successfully crossed into the LIPV occlusion, and then PV angiography showed LIPV occlusion (Figure G). A 0.014 in guidewire was exchanged with a microcatheter. Intravascular ultrasound (IVUS) showed a soft tissue-like hypoechoic lesion at the LIPV ostium (Figures 1 and 2, Supplementary data online, Movie S2). A successful balloon angioplasty was performed using two over-the-wire (OTW) balloons (4.0/40 mm and 6.0/20 mm) (Figure H); LIPV was fully dilated on PV angiography (Figure I) and IVUS (Figure 3, Supplementary data online, Movie S3).

Pulsed-field ablation: analysis of a new ablation technique for atrial fibrillation. A single centre experience

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Pulsed-field ablation (PFA) is a new non-thermal, tissue-specific ablation technique. Through the application of a local electric field, it is possible to induce a selective electroporation of cardiomyocytes membranes, resulting in myocytic apoptosis and sparing of non-myocardial structures (nerves, connective tissue, esophagus, vessels). Purpose A new PFA system for atrial fibrillation (AF) ablation has recently been introduced in our hospital. The aim of this retrospective review is to share the initial results of our experience in terms of acute efficacy and safety. Methods A total of 41 adult patients suitable for AF percutaneous ablation underwent PFA between April and November 2022 in our Institute. PFA system consisted of a current generator, a deflectable sheath and a multielectrode PFA catheter. Once inside the left atrium (LA), the PFA catheter was directed to the pulmonary veins (PVs) ostia through an over-the-wire system. Then, 8 electric impulses were applied for each PV to achieve electrical isolation; in some cases, applications to the posterior left atrium wall (LAPW) were delivered to obtain LAPW isolation (LAPWI). A moderate-to-deep sedation was provided by an anesthesiologist during all the procedures. Acute ablation efficacy was defined as absence of intracavitary signals at the electroanatomic mapping and local capture failure at the pacing maneuvers. Intra and peri-procedural safety was defined as the absence of major complications (pericardial effusion/ tamponade, stroke, vascular complications, death) during the procedure and the hospitalization period. Results Of the 41 patients included, 24 (58.5%) were treated for paroxysmal AF and 17 (41.5%) for persistent AF. In almost all cases (n=40, 97.6%) pulmonary veins isolation (PVI) was performed; in 14 cases (34.1%, almost all persistent AF patients) a LAPWI was performed with the application of a variable number of pulses (mean value = 13). In most of the cases (n=28, 68.3%) an electroanatomic mapping was acquired before and after the ablation. Acute efficacy was observed in all PVI cases (n=40, 100%) and in all LAPWI cases (n=14, 100%). No periprocedural major complications were observed (n=0, 0%). Conclusions PFA is a promising ablation technique capable of inducing selective myocytic apoptosis through electroporation, causing a thick damage across the muscle with no injury of other tissues, and could become a game changer in electrophysiology in the next future. Our initial data report a combination of ease of use and high efficacy and safety profiles.

His bundle pacing: 10-years follow-up

Abstract Funding Acknowledgements Type of funding sources: None. Background His bundle pacing (HBP) ensures a physiologic ventricular activation and can prevent pacing-induced cardiomyopathy. Published experiences confirm good clinical results on short-term follow-up. Data on long-term follow-up are still lacking Objective analyze clinical and technical results of HBP in an unselected population during a very long-term follow-up. Methods We retrospectively analyzed 370 patients (mean age 75±8 years; 221 males) with standard indication for pacing implanted with HBP from 2003 to 2012. In all cases the HBP implant was performed by lumenless fixed screw 3830 Medtronic and deflectable sheath C304. In 52% cases selective-HBP was obtained while 48% was non selective-HBP. The indications for pacing were AV block in 51%, sinus node disease in 22%, atrial fibrillation with slow ventricular rate in 25%, heart failure in 2%. Ischemic cardiopathy was found in 84 patients (29%); hypertension in 317 patients (86%) and diabetes in 108 patients (29%). Pre-implant QRS duration was 119±30 ms and basal mean EF 57±11%. The Hisian lead was inserted in ventricular port of a CRT-P device in 162 (44%) patients, in the atrial port of a DR device in 183 (49%) patients, and in the only channel of a SR device in 25 (7%) patients. A back-up standard lead was implanted in right ventricular apex or septum in 203 (55%) patients. Results All patients were followed by ambulatory check once a year. 124 (34%) patients reached 10 years follow-up (mean 12.3 ±1.8 years). At the end of follow-up, the mean EF was 61±8% (P=NS) and the mean paced QRS duration 123 ± 27 (P=NS). 10 (8%) patients had heart failure hospitalizations. 26 (21%) died after a mean of 12.1 ±1.7 years. From a technical point of view, 99 (80%) patients showed a good performance of the HBP lead at the last follow-up while 25 (20%) patients experienced lead-related problems: 20 (16%) had issues related to HBP lead (2 cases of severe HBP malfunction required hospitalization due to syncope) and 5 (4%) had malfunction of the back-up lead. The mean longevity of the devices was 6.6 ±2.6 years and each patient had 1.5 ±0.8 replacements. It was required to add a back up catheter in 3.6% of patients. The remaining 205 patients completed a mean follow-up of 6.3±2.7 years while 41(11%) patients were lost at follow-up (died within the first month post-implant or checked in other centres). Conclusion HBP is safe and feasible in the clinical practice. The system maintains a good performance during a long-term follow-up and ensures a physiologic ventricular contraction thus allowing good clinical outcome. The EF and QRS duration remain in normal values.

Is pulmonary vein isolation using pulse field ablation safe and efficient ? data from a prospective registry

Abstract Funding Acknowledgements Type of funding sources: None. Background Pulsed field ablation (PFA) is a nonthermal ablative modality using a strong electrical field created around a dedicated catheter to produce pores in the cellular membrane. As the amount of energy required to produce electroporation is highly tissue dependent, the atrial myocardium can be specifically targeted while sparing adjacent tissues. This new ablation modality could increase the safety of pulmonary vein isolation (PVI) procedures compared to PVI using thermal energies. Real-life clinical data are still limited regarding safety and efficacy of PFA. Purpose To assess safety and mid-term efficacy of PVI performed using PFA. Methods We included all patients who underwent PVI for symptomatic atrial fibrillation (AF) using PFA in our hospital between June 2021 and June 2022. All procedures were performed under general anaesthesia. After patients received IV heparin and achieved ACT > 300 s, a 12 Fr multi-electrode pentaspline PFA catheter was advanced through a 13 Fr deflectable sheath into the left atrium. The catheter was positioned so that the splines achieved circumferential contact at the PV antra. Two applications (2.5 sec and 2 kV per application) were performed in "basket" configuration, then the catheter was slightly rotated (30-40°) before delivery of 2 additional applications. This sequence of ablation was repeated in "flower" configuration. This protocol was applied at each pulmonary vein. PVI was assessed with the PFA catheter. A 24-hour holter monitoring was performed at 4-month and one-year follow-up. Results The population consisted of 102 patients (73 paroxysmal AF, 29 persistent AF) with a mean age of 56 ± 13 yo. The mean procedure duration was 38 ± 9 min, and mean fluoroscopy duration was 8 ± 4 min (4 ± 4.2 Gy.cm2). The pulmonary vein signal completely disappeared after the first PFA application for each targeted vein and PVI was confirmed for all veins in all patients at the end of the procedure. Pericardial effusion requiring percutaneous drainage occurred in 1 patient during the early phase of our experience (patient n°8). There was no other complication. At 4-month follow-up, 91/102 patients (89%) were asymptomatic with no recurrence of AF. At one-year follow-up, 34/38 patients (89%) had no reccurence of documented atrial arrhythmia. 6 patients underwent a redo procedure : pulmonary vein reconnection was observed in 4/6. Conclusion PVI performed with PFA appeared safe and efficient with short procedure and acceptable fluoroscopy durations. Further data are required regarding long-term efficacy.

AB-452672-3 PRE-CLINICAL PULSED-FIELD ABLATION (PFA) USING A SINGLE-SHOT CIRCULAR LINEAR ABLATION CATHETER FOR PV ISOLATION

Pulsed field ablation (PFA) is becoming the preferred energy treatment for pulmonary vein (PV) isolation. PFA application appears safe and effective and shortens procedure time. A circular linear ablation catheter may have advantages for single-shot delivery of PFA for PV isolation. To evaluate the feasibility of pusled field ablation for PV isolation with a circular linear ablation catheter. The Fiore™ catheter (EP Frontiers S.p.A., Italy; Figure) has two unique features: (1) an over the wire anchor and (2) an ablation element with linear electrodes. The anchor is positioned in the PV and guides the Circular Linear Ablation (CLA). The CLA can deliver PFA from a customized generator. Optimization of PFA parameters was conducted with a potato model in a saline bath by testing various energy pulses with bipolar and biphasic energy (500-1000 volts, pulse duration of 10-100 μs, interpulse pause of 10-400 μs, with a changing number of repetitions). The goal was to create circular ablations with a minimal depth of 3-4 mm. Following energy application images were acquired acutely and 18-24 hours after. Porcine in vivo testing (n=5 swine under general anaesthesia) with a deflectable sheath, evaluated PFA application at the left and right superior pulmonary vein, superior vena cava, and lateral wall of the right atrium with histopathology. In vitro ablations with three separate pulse trains demonstrated circular lesions with a diameter of up to 40 mm that were visible hours after the energy delivery. Average cross section of the circular lesions revealed an average depth of 3.2 mm with a surface width of 36 mm (Figure). Four applications (vs eight), from linear electrodes resulted in the most optimal and controlled circular lesions with central sparing and no off-target tissue destruction. Under fluoroscopic guidance, all positions in left and right atria, were easily accessed in all 5 animals (Figure). During PFA delivery, minimal skeletal muscle contraction was observed, without thermal ablation effect. Histopathology examination revealed acute changes in the atrial muscle structure. Chronic animal testing is ongoing to provide optimization of pulse trains and electrode to electrode sequencing to allow precise measurements of the PFA lesions depth. Following lesion optimization in an in vitro model, we demonstrate feasibility of delivering reproducible single-shot circumferential PFA lesions using a unique designed circular linear ablation catheter.

PO-01-187 FEASIBILITY OF FLUOROLESS PULMONARY VEIN ISOLATION USING A SINGLE-SHOT CONFORMABLE PULSED FIELD ABLATION CATHETER

Fluoroless pulmonary vein isolation (PVI) using point-by-point ablation catheters guided by electroanatomical mapping (EAM) systems is standard practice in many operators’ practice. While “single-shot” PVI tools have a streamlined procedural workflow, and with a safety profile enhanced by the emergence of pulsed field ablation (PFA) technology, these catheters have not been able to support a completely fluoroless workflow. A novel 8-Fr single-shot large lattice catheter with integrated magnetically-tracked EAM and PFA capabilities has been developed. To report for the first time the feasibility of performing single-shot PVI using a completely fluoroless approach. This 8 Fr PFA catheter (SpherePVI; Affera-Medtronic Inc) has a conformable large lattice framework that is expandable to 34 mm in diameter to permit “customization” to varying pulmonary vein anatomies (see Figure). It was delivered using an 8.5 Fr deflectable sheath (Agilis, Abbott Inc), and used with a custom EAM system (Prism-1; Affera-Medtronic Inc.) to render PV and left atrial anatomy. The PFA generator (HexaPULSE; Affera-Medtronic Inc) delivered biphasic waveforms (5 sec per application; 1.3-2.0 kV[±]); goal of 1-3 lesions per PV) from six elements situated circumferentially around the equatorial plane of the lattice. These cases conducted at a single center as part of a first-in-human study (NCT05115214): under general anesthesia, ICE was used to guide transeptal puncture and catheter positioning; fluoroscopy was initially used, followed by completely fluoroless ablation (using only ICE and EAM). The fluoroless cohort (n = 4 AF pts) was well matched with the control cohort (n = 5 AF pts) with similar baseline characteristics except for having more male patients (see Table). PVI was 100% successful in both groups. For PVI, both the number of PFA lesions delivered (16.3±0.5 vs 16.6±0.9 in the fluoroless and control groups, respectively) and the PVI ablation times (time only during lesion application; 1.6±0.0 min vs 1.6±0.1 min), and transpired time (defined as time transpiring between first to last lesion application; 8.3±1.1 min vs 9.6±2.2 min) were comparable. The total fluoroscopy time in the control group was 5.5±2.7 min. There were no serious adverse events in either group. This case series provides the proof-of-principle that fluoroless single-short PVI is feasible, safe and effective using a conformable large lattice PFA catheter.

PO-03-015 HIS BUNDLE PACING: OUTCOME AFTER 10-YEARS FOLLOW-UP

His bundle pacing (HBP) ensures a physiologic ventricular activation and can prevent pacing-induced cardiomyopathy. Published experiences confirm good clinical results on short-term follow-up. Data on long-term follow-up are still lacking. to analyze technical and clinical outcomes of HBP in an unselected population after a very long-term follow-up. Retrospective analysis of 370 patients (mean age 75±8 years; 221 males) with standard indication for pacing implanted with HBP from 2003 to 2012. In 52% selective-HBP was obtained while 48% were non selective-HBP. In all cases the HBP was performed by lumenless fixed screw lead and deflectable sheath C304. The indications for pacing were AV block 51%, sinus node disease 22%, atrial fibrillation and slow ventricular rate 25%, heart failure 2%. Ischemic cardiopathy was found in 84 pts (29%); hypertension in 317 pts (86%) and diabetes in 108 pts (29%). Pre-implant QRS was 119±30 ms and basal mean EF 57±11%. The His lead was inserted in ventricular port of CRT-P device in 162 (44%) pts, in atrial port of a DR device in 183 (49%) pts, and in ventricular channel of a SR device in 25 (7%) pts. A back-up lead was implanted in right apex or septum in 203 (55%) patients. All patients were checked once a year. 124 (34%) pts overstepped 10 years follow-up (mean 12.3 ±1.8 years), they were analyzed on technical and clinical performance. At the end of follow-up, the mean EF was 61±8% (P=NS) and the mean paced QRS 123 ± 27 (P=NS). 10 (8%) patients had heart failure hospitalizations. 26 (21%) died after 12.1 ±1.7 years. From a technical point of view, 99 (80%) pts showed good performance of the HBP lead at the last follow-up while 25 (20%) pts experienced lead-related problems: 20 (16%) had HBP lead issues (2 cases of severe HBP malfunction required hospitalization due to syncope) and 5 (4%) had malfunction of the back-up lead. The mean devices longevity was 6.6 ±2.6 years and each patient had 1.5 ±0.8 replacements. It was required to add a back-up catheter in 3.6% of patients. The remaining 205 patients completed a mean follow-up of 6.3±2.7 years while 41(11%) patients were lost at follow-up (died within the first month post-implant or checked in other centres). HBP is safe and feasible in the clinical practice. The system maintains a good performance during a long-term follow-up and ensures a physiologic ventricular contraction thus allowing good clinical outcome. The EF and QRS duration remain in normal values.

AB-452675-2 PULMONARY VEIN ISOLATION USING A NOVEL MAP-AND-ABLATE SPHERICAL ARRAY PULSED FIELD ABLATION CATHETER: THE PULSE-EU PAROXYSMAL AF COHORT

Despite the promise of pulsed field ablation (PFA), there is much about the biophysics of this novel energy technology that remains to be understood. Preclinical studies have shown that close electrode-tissue proximity increases the likelihood of achieving transmural PFA lesions by maximizing the electric field penetration into the target tissue. The current single-shot PFA catheters are capable of performing pulmonary vein isolation (PVI), but cannot reliably confirm tissue contact. To report the clinical outcomes using a novel Map-and-Ablate spherical array multielectrode catheter that is able to verify tissue contact and deliver single-shot PFA. In the first-in-human PULSE-EU study, paroxysmal AF pts underwent PVI using the spherical array PFA catheter (Globe; Kardium Inc., Canada) using a 16Fr deflectable sheath under general anesthesia and ICE-guidance. Using a custom mapping system integrated with the PFA catheter (GPS; Kardium Inc.) the array catheter rendered contact and voltage anatomic maps. The spherical array was positioned at each PV ostia and PF applications (1.7 kV/lesion, ungated, micro-second scale pulses) were delivered after verifying tissue contact (Figure). Follow-up included post-procedure EGD and plans for protocol-mandated invasive remapping at 2-3 mo after the index procedure. A total of 24 pts (age 59.9±10.8 years; gender women-37.5%; LA 42.5±3.7 mm; LVEF 62.6±8.0%%) underwent PVI with a total procedure duration of 71.5±22.9 min. All PVs (96 of 96 PVs) were acutely isolated, typically with a single application. There were no acute reconnections. The total pulse delivery time and LA catheter dwell time were 42.2±7.6 sec and 36.8±13.7 min, respectively. There were no serious procedure or device related adverse events including no stroke/TIA, pericardial effusion, phrenic nerve injury, or esophageal complications. One patient had pericarditis which was treated medically. Post-procedure EGD revealed no thermal injury in 21 of 21 pts. PV remapping has thus far been performed in 6 pts, and revealed durable PVI in all 24 of 24 (100%) PVs. [Remapping data on the remaining cohort will be available by May 2023.] In this first-in-human PULSE-EU clinical study, the spherical array PFA catheter was able to render atrial anatomy, isolate PVs (with initial data indicating 100% durability), and perform pre-/post- electrical mapping.

PO-03-069 COHERENT SINE BURST ELECTROPORATION (CSE) FOR PULSED FIELD ABLATION: PRELIMINARY CLINICAL OUTCOMES FOR TREATMENT OF PAROXYSMAL AND PERSISTENT AF IN THE BURST-AF TRIAL

Pulsed field ablation (PFA) has a promising safety profile for treatment of atrial fibrillation. PFA is currently implemented using square waves and varying circular, multi-spline, focal, or basket catheter designs. Coherent Sine Burst Electroporation (CSE) is a novel PFA platform that uses phased sine waves delivered via a configurable catheter to produce linear, circular, or focal lesions. Investigate the acute safety and efficacy of CSE for pulmonary vein isolation (PVI), posterior wall isolation (PWI), and cavo-tricuspid isthmus (CTI) ablation in patients with paroxysmal (PAF) and persistent AF (PersAF). BURST-AF is a first-in-human, non-randomized, multicenter, single-arm trial of PAF and PersAF ablation (NCT05572047). CSE was delivered with sine waves of amplitude 2400–2900V (standard-energy) and 3000–3500V (high-energy) using a multi-configurable 7F ablation catheter (Arga MedTech Inc, San Diego, CA, USA). After informed consent and under general anesthesia, ICE-guided transseptal puncture was performed. An 8.5F deflectable sheath guided the ablation catheter into the left atrium (LA). Electro-anatomic anatomy and voltage maps were created. A minimum of 3 applications of ablation per vein including rotation were applied at each PV ostium to achieve PVI. In patients (pts) with PersAF, the linear configuration was used for PWI and CTI. PV entrance and exit block was assessed after 20-min waiting period. ICE was used to assess microbubble formation. Re-map will be performed 60-days post procedure to evaluate lesion durability. The first 5 pts were enrolled in Oct 2022. Acute safety was observed for all pts (age 62.6 ± 7.56 yrs, F/M = 80/20%, BMI 32 ± 5.7). No serious adverse events occurred. First-pass acute electrical isolation was achieved in 100% of PVs (n=20) and also in the PersAF pt for PWI and CTI. PVI duration (from 1st to last lesion) was 46.6 ± 28.5min (range 28 - 95). PVI LA dwell time was 58.6 ± 37.7min and fluoro time was 20.4 ± 6.8 min. Initial findings of CSE PFA demonstrated acute first-pass efficacy for PVI, PWI, and CTI. Additional pts and re-map data for durability assessment will be available at time of presentation. CSE allows application of high energy protocols (up to 3500V) with no microbubble formation and minimal to no muscle stimulation. The CSE Ablation Catheter facilitates focal, linear, and circular ablations, comprising a highly versatile tool for cardiac arrhythmias.

AB-453068-2 IS PULMONARY VEIN ISOLATION USING PULSE FIELD ABLATION SAFE AND EFFICIENT ? DATA FROM A PROSPECTIVE REGISTRY

Pulsed field ablation (PFA) is a nonthermal ablative modality using a strong electrical field created around a dedicated catheter to produce pores in the cellular membrane. As the amount of energy required to produce electroporation is highly tissue dependent, the atrial myocardium can be specifically targeted while sparing adjacent tissues. This new ablation modality could increase the safety of pulmonary vein isolation (PVI) procedures compared to PVI using thermal energies. Real-life clinical data are still limited regarding safety and efficacy of PFA. To assess safety and mid-term efficacy of PVI performed using PFA. We included all patients who underwent PVI for symptomatic atrial fibrillation (AF) using PFA in our hospital between June 2021 and June 2022. All procedures were performed under general anaesthesia. After patients received IV heparin and achieved ACT > 300 s, a 12 Fr multi-electrode pentaspline PFA catheter was advanced through a 13 Fr deflectable sheath into the left atrium. The catheter was positioned so that the splines achieved circumferential contact at the PV antra. Two applications (2.5 sec and 2 kV per application) were performed in "basket" configuration, then the catheter was slightly rotated (30-40°) before delivery of 2 additional applications. This sequence of ablation was repeated in "flower" configuration. This protocol was applied at each pulmonary vein. PVI was assessed with the PFA catheter. A 24-hour holter monitoring was performed at 4-month and one-year follow-up. The population consisted of 102 patients (73 paroxysmal AF, 29 persistent AF) with a mean age of 56 ± 13 yo. The mean procedure duration was 38 ± 9 min, and mean fluoroscopy duration was 8±4 min (4±4.2 Gy.cm2). The pulmonary vein signal completely disappeared after the first PFA application for each targeted vein and PVI was confirmed for all veins in all patients at the end of the procedure. Pericardial effusion requiring percutaneous drainage occurred in 1 patient during the early phase of our experience (patient n°8). There was no other complication. At 4-month follow-up, 91/102 patients (89%) were asymptomatic with no recurrence of AF. At one-year follow-up, 34/38 patients (89%) had no reccurence of documented atrial arrhythmia. 6 patients underwent a redo procedure : pulmonary vein reconnection was observed in 4/6. PVI performed with PFA appeared safe and efficient with short procedure and acceptable fluoroscopy durations.

PV Isolation Using a Spherical Array PFA Catheter: Application Repetition and Lesion Durability (PULSE-EU Study)

BackgroundPreclinical studies have revealed that pulsed field ablation (PFA) lesion dimensions increase with repetitive applications at a similar electric field. ObjectivesThis study investigated whether pulmonary vein isolation (PVI) durability varies with single vs repetitive pulsed field (PF) applications. MethodsAtrial fibrillation patients underwent PVI using a spherical multielectrode array PFA catheter delivered with a 19-F deflectable sheath under intracardiac echocardiographic guidance. Esophagogastroduodenoscopy and brain magnetic resonance imaging were performed within 1 to 3 days, and invasive remapping at ∼2 to 3 months. ResultsThe patient cohort (n = 21; age 63 ± 11 years; 67% women) underwent PVI in either of 2 groups: group 1 (n = 11)—single PF application/PV; and group 2 (n = 10)—3 PF applications/PV. In both groups, PVI was acutely successful in all (100%) patients. Despite significantly longer pulse delivery times (75.2 ± 7.4 s/patient vs 24.5 ± 5.5 s/patient) the procedure times (73.2 ± 13.7 minutes vs 93.7 ± 18.5 minutes) were shorter with group 2 vs group 1. There was no stroke/transient ischemic attack, pericardial effusion, phrenic nerve injury, or esophageal complications. Esophagogastroduodenoscopy was normal in both groups of patients (n = 9). Screening brain magnetic resonance imaging revealed asymptomatic cerebral lesions (diffusion weighted imaging+/fluid attenuated inversion recovery−) in 3 of 16 (18.7%) patients. PV remapping revealed durable PVI in 62.5% PVs in group 1 (n = 10), compared with all 100% PVs in group 2 (n = 9); this translates to all PVs being durably isolated in 30% vs 100% (P < 0.05) of patients in groups 1 and 2, respectively. ConclusionsIn his first-in-human trial, the “single-shot” spherical array PFA catheter was shown to safely isolate PVs. Repetitive PF application is key for lesion consolidation to maximize PVI durability.

Pulmonary vein isolation using pulse field ablation: Acute results from a multicentric registry

Pulsed field ablation (PFA) is a nonthermal ablative modality using a strong electrical field created around a dedicated catheter to produce pores in the cellular membrane. As the amount of energy required to produce electroporation is highly tissue dependent, the atrial myocardium can be specifically targeted while sparing adjacent tissues. Theoretically, this new ablation modality could increase the safety of pulmonary vein isolation (PVI) procedures compare to PVI using thermal energies. Real-life clinical data are still lacking regarding feasibility and safety of PFA. To assess feasibility and safety of PVI performed using PFA. We included all patients who underwent PVI for symptomatic atrial fibrillation (AF) using PFA in 3 hospitals (6 operators) between June 2021 and April 2022. All procedures were performed under general anaesthesia or deep sedation. After patients received IV heparin and achieved ACT > 300 s, a 12 Fr multi-electrode pentaspline PFA catheter (Farawave, Farapulse Inc.) was advanced through a 13 Fr deflectable sheath into the left atrium. The catheter was positioned so that the splines achieved circumferential contact at the PV antra. 2 applications (2.5 sec and 2 kV per application) were performed in the “basket” configuration, then the catheter was slightly rotated (30–40°) before delivery of 2 additional applications. This sequence of ablation was repeated in the “flower” configuration. This protocol was applied at each PV. PVI was assessed with the Farawave catheter. The population consisted of 126 patients (76 paroxysmal AF, 50 persistent AF < 6 months) with a mean age of 61 ± 12 yo. Left atrial dimension was normal in 72 patients (57%) and enlarged in 54 (43%). The mean procedure duration was 47 ± 20 min, and mean fluoroscopy duration was 17 ± 7 min. The pulmonary vein signal completely disappeared after the first PFA application for each targeted vein and PVI was confirmed for all veins in all patients at the end of the procedure. Pericardial effusion occurred in 3 patients (2.4%), 2 requiring percutaneous drainage. No other complications were observed (Fig. 1). PVI performed with PFA is safe and feasible without compromising procedure and scopy durations. Further data are necessary regarding mid- and long-term efficacy.

Abstract 15646: The Need for Speed - Early Experience of Very High-Power Short Duration (QDOT TM ) Ablation

Introduction: Ablation is a cornerstone of therapy for atrial fibrillation (AF), as well as one of the most common procedures in electrophysiology. Use of intermediate-power ablation has given way to high-power short duration radiofrequency ablation. However, more recently the emergence of very high-power very short duration (vHPvSD) ablation at 90W may prove to be more efficient and effective in the management of AF. The radius of the resistive heating zone is increased, while the conductive heating zone tapers off more quickly, potentially reducing collateral tissue damage. Methods: This was a single centre prospective study using the QDOT TM (Biosense Webster, Irvine, California) ablation catheter. Our workflow involves double trans-septal puncture via TOE guidance, use of a deflectable sheath, LASSO 10-pole mapping for first time AF ablations or PENTARAY TM for redo procedures, ablation while paced in sinus rhythm were possible, general anaesthetic, low tidal volumes, and an I:E ratio of 1:4. All pulmonary vein isolations (PVI) and posterior wall isolations (PWI) were performed at 90W for 4s, while cavo-tricuspid isthmus (CTI) lines were completed using QMode at 40W for 20s. Results: 65 patients under went vHPvSD for treatment of atrial fibrillation. Of these 12 were re-do cases that had previously been treated with either radiofrequency or cryo-ablation. The average age was 58.9±9.7 (yrs) with 73% males. Paroxysmal atrial fibrillation was seen in 69%, 31% had persistent AF, and 7% had co-morbid atrial flutter. The average CHADSVASC score was 1.18±1.03. Pulmonary vein isolation was achieved in 100% of patients, 10% had posterior wall isolation, and 16% underwent cavo-tricuspid isthmus ablation. Average skin-to-skin and total ablation times were 58.2±13.1 (mins) and 23.4±6.5 (mins), respectively. Average RF time was 8.1±0.7 (mins). Mean follow up was 126±21 days, where 2 recurrences were seen. We saw no complications in our patient cohort. Conclusions: The method of vHPvSD is safe and durable in the treatment of atrial fibrillation. Total procedure time and RF time were significantly lower than previous RF ablation therapies. This relatively large study on the safety and early efficacy of vHPvSD adds to the emerging data on this promising technology.

First-in-Human Experience of Using a Universal Steerable Sheath in Implanting Left Atrial Appendage Closure Devices.

Left atrial appendage (LAA) closure (LAAC) device implantation may be challenging in cases with difficult LAA anatomy. A deflectable sheath to approach multiple LAA positions may be helpful. We used a deflectable sheath to implant LAAC devices in 20 patients and included 60 cases using the standard sheaths for comparison. The procedures were successful in all patients without peri-procedural complications. After a median follow-up of 1.52 (IQR: 0.76-2.33) years, none of the patients in the deflectable sheath group had peri-device leak≥3mm and experienced thromboembolic stroke. In the standard sheath group, after follow-up of 2.03 (IQR: 0.87-3.19) years, 2 had peri-device leak≥3mm and 1 experienced thromboembolic stroke. We first proved the idea of using a universal steerable sheath for LAAC device implantation in difficult LAA anatomy, which also allows rapid switching of different LAAC devices.

PO-623-08 FIRST-IN-HUMAN CLINICAL EXPERIENCE OF A NOVEL CONFORMABLE "SINGLE-SHOT" PULSED FIELD ABLATION CATHETER FOR PULMONARY VEIN ISOLATION

Pulsed field ablation (PFA) has safety and procedural workflow advantages over conventional thermal ablation. Most “single-shot” PFA catheters are either not linked to mapping systems, require serial re-positioning or cannot easily accommodate varying PV anatomies. Recently, a novel 8-Fr single-shot large lattice PFA catheter that can conform to anatomies has been developed. In a first-in-human single-arm trial (NCT05144503, NCT05115214) of PAF ablation, we assessed the acute safety and efficacy of PVI using this single-shot PFA catheter. The 8Fr PFA catheter (SpherePVI; Affera Inc) has a large compressible/conformable lattice framework (expandable up to 34 mm diameter), and consists of 6 sections that are independently and sequentially energized for ablation. Under general anesthesia and after ICE-guided transseptal puncture, an 8.5 Fr deflectable sheath (Agilis, Abbott Inc) was used in concert with the PFA catheter and custom mapping system (Prism-1, Affera Inc) to quickly render the PV anatomy. Then the catheter was serially positioned at the ostium of each PV, and a PFA generator (HexaPULSE; Affera Inc) delivered biphasic pulse trains (5 sec per application; 1.3-2.0 kV [±]); goal of 1-3 lesions per PV. Post-procedure endoscopy (EGD) and brain MRI occurred within 24-72 hours. At 3 centers (5 operators), a total of 30 pts (age 57.6 ± 9.3 yrs; M / F = 15 / 15) underwent PVI. Mapping time to render the LA-PV anatomy was 5.7±3.2 min (range 1.3 - 13.1). PVI was acutely successful in all 30 pts: 122 of 122 (100%) PVs were acutely isolated using 2.4±0.4 applications/vein (10.0±1.6 applications/pt). The PVI duration time (transpired from 1st to last lesion) was 8.2±5.5 min (range 3.3 - 29.8). The total LA catheter dwell time for the PFA catheter was 12.9±7.6 min (range 5.0 - 36.0). Fluoroscopy time was 4.8±4.1 min. There were no serious adverse events - including no esophageal fistula, stroke/TIA, phrenic injury or tamponade. EGD in 18 pts revealed no thermal lesions, and brain MRI revealed acute lesions in 2 of 21 (9.5%) pts. PVI using the conformable “single-shot” PFA catheter was acutely successful and safe. Further studies should assess lesion durability and large multicenter clinical outcomes.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

INTERMEDIATE TERM PERFORMANCE AND SAFETY OF LEFT BUNDLE BRANCH AREA CONDUCTION SYSTEM PACING LEADS: A MULTICENTER PROSPECTIVE STUDY

<h3>BACKGROUND</h3> Left bundle branch area pacing (LBBAP) has shown to be a reliable alternative to His bundle pacing (HBP) for physiologic pacing. There are limited data on the intermediate term performance of LBBA pacing leads. Objective: To evaluate the intermediate term performance and safety of LBBAP. <h3>METHODS AND RESULTS</h3> Patients referred for pacemaker implantation at two academic centers between 02/2019 - 1/2021 were considered for LBBAP. LBBAP was performed by implanting the 3830 lumenless lead using the C315 fixed curve or C304 His deflectable sheath (Medtronic, MN). Implant success rates, complications and electrophysiological parameters were assessed. LBBAP was successful in 566/619 patients (91%). Mean age was 73±12 yrs, 46% were women. 37% had QRSd >130 ms, 25% RBBB, 11% LBBB, 4% IVCD. Pacing indications include sinus node dysfunction in 27%, AV block 56%, CRT 7% and refractory AF 10%. Mean procedural duration was 73±32 mins (median 70 mins) and fluoroscopic time was 10±7 mins (median 8 mins). Baseline QRSd was 119±31ms vs paced QRSd was 113±12ms (p < 0.001). Mean LV activation time was 73±12ms at high output and 76±12ms at low output. LBB potentials were noted in 175 (31%) patients. Transition from non-selective to selective LBBA or septal pacing was noted in 393 (74%). Pacing threshold and R waves were 0.74±0.3V@0.4ms and 11±5mV at implant and 0.83±0.2V@0.4ms and 15± 5mV at a mean follow-up of 167±172 days (range 25-662 days) (Fig). The only complication was LBBAP lead dislodgement in 6 (1%) patients occurring within 24-72 hours. <h3>CONCLUSION</h3> LBBA pacing is safe and feasible with high success rates and low complication rates during intermediate term follow-up.

B-PO04-133 INTRACARDIAC ECHOCARDIOGRAPHY AS AN ADJUNCTIVE TOOL FOR RECURRENT ACCESSORY PATHWAYS ABLATION

Acute success rate of AP ablation is reported to 90 and 99% with first procedure, however, relapse reaches 7 to 22%. AP relapse is related to right-sided AP, multiple AP’s and congenital heart defects. We describe a series of failed AP catheter ablation requiring reintervention with contemporary technologies including intracardiac echocardiography, to analyze if this technology improve efficacy and safety of AP ablation. A multi-center, descriptive, retrospective study of patients over 18 y/o, who required reintervention of AP ablation, between February 2017 and April 2020. Patients were identified using the electrophysiology procedures database. Data were obtained from descriptions and images review. We included 35 patients. Mean age 38,8 y/o. Single previous catheter ablation attempt in 60%, while 40% had 2 or more previous attempts. Technologies used for reinterventions of AP included 3D mapping systems, ICE (100%), and deflectable sheath (100%). Procedure´s mean duration was 180 mins,13 mins of mean fluoroscopic time. Acute success was 100%, and 8.5% of recurrence during follow up. Most frequent AP location were posteroseptal (22%), and anterolateral (17%). Anatomical instability was the main obstacle identified (74%), followed by risk of adjacent structure injury (17%). No complications described. Using intracardiac echocardiography during reintervention of AP catheter ablation could lead to a high acute success rate with low recurrence. Anatomic location and instability were the main causes of recurrence, the use of ICE allows a more exact location of the av junction with better signals mapping and safer ablation.