Cryocure-VT: the safety and effectiveness of ultra-low-temperature cryoablation of monomorphic ventricular tachycardia in patients with ischaemic and non-ischaemic cardiomyopathies.

AIMS: The ultra-low-temperature cryoablation (ULTC) ablation system using -196°C N2 cryogen has been reported to create lesions with freeze duration-dependent depth titratable to over 10 mm with minimum attenuation by scar. Cryocure-VT (NCT04893317) was a first-in-human clinical trial evaluating the safety and efficacy of a novel, purpose-built ULTC catheter in endocardial ablation of scar-dependent ventricular tachycardias (VTs). METHODS AND RESULTS: This prospective, multi-centre study enrolled patients referred for de novo or second ablations of recurrent monomorphic VT of both ischaemic and non-ischaemic aetiologies. Primary safety and efficacy endpoints of the study were freedom from device- or procedure-related major adverse events (MAEs) up to 30 days post-ablation, acute non-inducibility of clinical VTs at the end of the procedure, and freedom from sustained VT or implantable defibrillator intervention at 6 months. Ultra-low-temperature cryoablation was performed in 64 patients (age 67 ± 11 years, 78% ischaemic, ejection fraction = 35 ± 10%) at 9 centres. The primary acute effectiveness endpoint was achieved in 94% (51/54) of patients in whom post-ablation induction was attempted. There were no protocol-defined MAEs; four procedure-related serious adverse events resolved without clinical sequelae. At 6-month follow-up, 38 patients (60.3%) remained VT-free, and freedom from defibrillator shock was 81.0%, with no significant difference between ischaemic and non-ischaemic cohorts. In 47 patients with defibrillator for at least 6 months prior to the ablation, the VT burden was reduced from median of 4, inter-quartile range (IQR, 1-9) to 0, IQR (0-2). CONCLUSION: In this first-in-human multi-centre experience, endocardial ULTC ablation of monomorphic VT appears safe and effective in patients with both ischaemic-cardiomyopathy and non-ischaemic-cardiomyopathy. CLINICAL TRIAL REGISTRATION: NCT04893317.

Embolization of percutaneous left atrial appendage closure devices: Timing, management and clinical outcomes.

BACKGROUND: Left atrial appendage (LAA) occluder embolization is an infrequent but serious complication. OBJECTIVES: We aim to describe timing, management and clinical outcomes of device embolization in a multi-center registry. METHODS: Patient characteristics, imaging findings and procedure and follow-up data were collected retrospectively. Device embolizations were categorized according to 1) timing 2) management and 3) clinical outcomes. RESULTS: Sixty-seven centers contributed data. Device embolization occurred in 108 patients. In 70.4 % of cases, it happened within the first 24 h of the procedure. The device was purposefully left in the LA and the aorta in two (1.9 %) patients, an initial percutaneous retrieval was attempted in 81 (75.0 %) and surgery without prior percutaneous retrieval attempt was performed in 23 (21.3 %) patients. Two patients died before a retrieval attempt could be made. In 28/81 (34.6 %) patients with an initial percutaneous retrieval attempt a second, additional attempt was performed, which was associated with a high mortality (death in patients with one attempt: 2.9 % vs. second attempt: 21.4 %, p < 0.001). The primary outcome (bailout surgery, cardiogenic shock, stroke, TIA, and/or death) occurred in 47 (43.5 %) patients. Other major complications related to device embolization occurred in 21 (19.4 %) patients. CONCLUSIONS: The majority of device embolizations after LAA closure occurs early. A percutaneous approach is often the preferred method for a first rescue attempt. Major adverse event rates, including death, are high particularly if the first retrieval attempt was unsuccessful. CONDENSED ABSTRACT: This dedicated multicenter registry examined timing, management, and clinical outcome of device embolization. Early embolization (70.4 %) was most frequent. As a first rescue attempt, percutaneous retrieval was preferred in 75.0 %, followed by surgical removal (21.3 %). In patients with a second retrieval attempt a higher mortality (death first attempt: 2.9 % vs. death second attempt: 24.1 %, p < 0.001) was observed. Mortality (10.2 %) and the major complication rate after device embolization were high.

Paroxysmal Atrial Fibrillation Ablation Using a Novel Variable-Loop Biphasic Pulsed Field Ablation Catheter Integrated With a 3-Dimensional Mapping System: 1-Year Outcomes of the Multicenter inspIRE Study.

BACKGROUND: The inspIRE study (Study for Treatment of Paroxysmal Atrial Fibrillation [PAF] by Pulsed Field Ablation [PFA] System With Irreversible Electroporation [IRE]) evaluated safety and effectiveness of a fully integrated biphasic pulsed field ablation (PFA) system with a variable-loop circular catheter for the treatment of drug-refractory paroxysmal atrial fibrillation. METHODS: Subjects underwent pulmonary vein (PV) isolation with the PFA system, using at least 12 applications per vein; adenosine/isoproterenol was administered to confirm entrance block. Wave I assessed initial safety, including for esophageal lesions, silent cerebral lesions, and PV stenosis. Wave II (pivotal phase) tested (1) primary safety, incidence of early-onset primary adverse events, and (2) primary effectiveness, confirmed PV isolation with freedom from documented atrial arrhythmia at 12 months. The study design specified an interim analysis to determine early success once 30 subjects reached the 12-month follow-up and all subjects reached 3-month follow-up. RESULTS: Across 13 centers in Europe/Canada, 226 subjects were enrolled, met criteria for safety and effectiveness evaluations, and received PFA (Wave I, 40; Wave II, 186). Wave I demonstrated no esophageal thermal lesions or PV stenosis. Among 39 subjects with cerebral magnetic resonance imaging, silent cerebral lesions were detected in 4 of the first 6 subjects, after which workflow enhancements, including a 10-second pause between PFA applications, were implemented; subsequently, only 4 of 33 subjects had silent cerebral lesions. In the Wave II phase, no primary adverse events were reported. Upon declaring early success, 83 subjects reached 12-month follow-up. With 100% entrance block, PV isolation without acute reconnection was achieved in 97.1% of targeted veins. For Wave II, the primary effectiveness end point per Kaplan-Meier at the time of interim analysis was 70.9%; 12-month freedom from symptomatic atrial fibrillation/atrial flutter/atrial tachycardia recurrence and repeat ablation was 78.9% and 92.3%, respectively. Total procedure and transpired PFA times were 70.1±27.7 and 26.7±14.0 minutes, respectively. CONCLUSIONS: The inspIRE trial confirmed the safety and effectiveness of the novel mapping-integrated PFA system. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; unique identifier: NCT04524364.

First-in-Human Experience With Ultra-Low Temperature Cryoablation for Monomorphic Ventricular Tachycardia.

Ultra-low temperature cryoablation (ULTC) using near-critical nitrogen (-196ºC) has been shown to produce durable, contiguous, transmural lesions in ventricles of animal models. This report summarizes acute experience with ULTC in the first-ever 13 patients with recurrent monomorphic ventricular tachycardias (VTs) of both ischemic cardiomyopathy and nonischemic etiologies enrolled in the CryoCure-VT (Cryoablation for Monomorphic Ventricular Tachycardia; NCT04893317) clinical trial. After an average of 9.6 ± 4.6 endocardial ULTC lesions per patient, no clinical ventricular tachycardias were inducible in 91% of patients. Two procedure-related serious adverse events recorded in 2 patients resolved post-procedurally without clinical sequelae. Further investigation of both acute and chronic outcomes is warranted and ongoing.

Combined pulsed field ablation with ultra-low temperature cryoablation: A preclinical experience.

BACKGROUND: Combining pulsed field ablation (PFA) with ultra-low temperature cryoablation (ULTC) represents a novel energy source which may create more transmural cardiac lesions. We sought to assess the feasibility of lesions created by combined cryoablation and pulsed field ablation (PFCA) versus PFA alone. METHODS: Ablations were performed using a custom PFA generator, ULTC console, and an ablation catheter with insertable stylets. PFA was delivered in a biphasic, bipolar train. PFCA precooled the tissue for 30 s followed by a concurrent PFA train. Benchtop testing using Schlieren imaging and microbubble volume assessment were used to compare PFA and PFCA. PFA and PFCA lesions using pre-optimized and optimized ablation protocols were studied in 6 swine. Pre and post-ECGs were recorded for each ablation and a gross necropsy was performed at 14 days. RESULTS: Consistent with benchtop comparisons of heat and microbubble generation, PFA deliveries in the animals were accompanied by muscle contractions and significant microbubbles (Grade 2-3) visible on intracardiac echo while neither occurred during PFCA at higher voltage levels. Both PFA and PFCA acutely eliminated or highly attenuated (>80%) local atrial electrograms. Histology of PFA and PFCA lesions indicated depth up to 6-7 mm and nearly all lesions were transmural. Optimized PFCA produced wider cavotricuspid isthmus lesions with evidence of tissue selectivity. CONCLUSION: A novel technology combining PFA and ULTC into one energy source demonstrated in-vivo feasibility for PFCA ablation. PFCA had a more favorable thermal profile and did not produce muscle contraction or microbubbles while extending lesion depth beyond cryoablation.

Ultra-Low Temperature Cryoablation for Atrial Fibrillation: Primary Outcomes for Efficacy and Safety: The Cryocure-2 Study.

Ultra-low temperature cryoablation (ULTC) is a novel ablation modality aiming to combine the effectiveness of surgical lesion delivery with percutaneous safety to improve outcomes in catheter ablations of atrial fibrillation, particularly in persistent AF (PsAF). In the Cryocure-2 study (NCT02839304) 78 patients (56.4% PsAF) received ULTC pulmonary vein isolation plus posterior wall ablation, and linear left and right atrial lesions as needed. The safety and acute success of ULTC appear consistent with current catheter ablation techniques and, together with Kaplan-Meier 85.9% 1-year freedom from AF observed in Cryocure-2 PsAF patients, warrant further evaluation in larger clinical trials, which are currently ongoing.

Independent factors of low radiation dose during atrial fibrillation ablation with cryoballoon or radiofrequency: Results from the "Go for zero fluoroscopy" registry.

AIMS: Atrial fibrillation (AF) catheter ablation is a common procedure requiring in most cases the use of fluoroscopy. We aimed to evaluate the factors associated with a lower dose of fluoroscopy used during AF ablation with cryoballoon or radiofrequency. METHODS: In this prospective European registry, centers were requested to provide procedural characteristics of consecutive AF ablation cases. Lower doses of fluoroscopy were defined as those with dose-area-product (DAP) under the median dose used in the radiofrequency and the cryoballoon ablation groups. RESULTS: A total of 638 AF ablation procedures were collected (n = 492 for radiofrequency and n = 146 for cryoballoon ablation groups) in 25 centers. The median [IQR] DAP were 926 [349;2092] and 1516 [418;3408] cGy*cm2 in the radiofrequency and cryoballoon groups, respectively. Main factors associated with lower DAP in cryoballoon ablation group were electrophysiology dedicated laboratory (OR 6.04, 95%CI 1.16-31.54; P = .03) and frequent dosimetry report (OR 21.39, 95%CI 5.43-98.54; P = .03). Main factors associated with lower DAP in the radiofrequency ablation group were the use of a chest dosimeter (OR 12.57, 95% CI 2.88-54.90; P = .01), biplane X-ray equipment (OR 3.12, 95%CI 1.89-5.16; P < .01), university hospital (OR 2.10, 95%CI 1.35-3.25; P = .01), electrophysiology dedicated laboratory (OR 2.45, 95%CI 1.48-4.05; P < .01) and use of contact force enabled catheter (OR 22.60, 95%CI 6.82-74.88; P < .01). CONCLUSION: This real-life study of fluoroscopy use during AF ablation provides new data about current practices across European countries. Technological advances and quality of the fluoroscopic environment were the main factors associated with lower radiation dose during AF ablation.

Ultralow temperature cryoablation using near-critical nitrogen for cavotricuspid isthmus-ablation, first-in-human results.

INTRODUCTION: Cryoablation has evolved as a safe alternative to radiofrequency ablation in the treatment of several supraventricular arrhythmias and has potential advantages, yet is limited by the properties of the cryogen used. We investigated a novel ultralow temperature cryoablation (ULTC) system using nitrogen near its liquid-vapor critical point as a freezing source, achieving temperatures as low as -196 degrees Celsius in a long linear catheter with a continuous energy release. Initial safety, procedural and efficacy outcomes of ULTC are described in patients undergoing cavotricuspid isthmus (CTI) ablation. METHODS AND RESULTS: The Cryocure studies (NCT02355106, NCT02839304) are prospective, single-arm, multi-center, first-in-human clinical studies in 17 patients with atrial flutter (AFL) and 13 patients with atrial fibrillation (AF). A total of 30 patients, mean age 65 ± 8 years old and 67% male, were enrolled and underwent ablation of the CTI. Acute success, defined as the confirmation of stable bidirectional conduction block across the CTI, was achieved in all 30 patients. After 12 months of follow-up, 14 out of 17 AFL patients remained free from any AFL. One (3.3%) procedure-related but not device-related serious adverse event was reported, involving transient inferolateral ST-elevation associated with temporary AV conduction block. CONCLUSION: In this first-in-human clinical study the safety and performance results demonstrate the capabilities of ultralow temperature near-critical nitrogen as an effective energy source for CTI ablation. Ongoing, larger, studies should confirm our findings and evaluate the capabilities to create linear and focal transmural lesions in other arrhythmias.

Radiation Safety and Electrophysiologists: Radiation Protection Status - Go for Zero Fluoroscopy European Heart Rhythm Association Registry.

BACKGROUND: The purpose of this study was to analyze electrophysiologists' radiation-protective devices for occupational exposure across European countries. METHODS: Data reported herein were gathered from the international, multicenter prospective Go for Zero Fluoroscopy registry performed in years 2018-2019. The registry encompassed 25 European electrophysiological centers from 14 countries and up to 5 operators from each center. RESULTS: The analysis included 95 operators (median age: 39 years, 85% of male, median training time: 5 years). The most frequently used X-ray protection tools (used by ≥80% of the group) were lead aprons, thyroid shields, screens below the table, glass in the laboratory, and least often (<7%) protective gloves and cabin. No statistically significant differences regarding the number of procedures performed monthly, electrophysiologists' experience and gender, and radiation exposure dose or radiation protection tools were observed, except lead thyroid shields and eyeglasses, which were more often used in case of fewer electrophysiological procedures performed (<20 procedures per month). Operators who were protected by >4 X-ray protection tools were exposed to lower radiation levels than those who were protected by ≤4 X-ray protection tools (median radiation exposure: 0.6 [0.2-1.1] vs. 0.2 [0.1-0.2] mSv per month, p < 0.0001; 1.1 [0.1-12.0] vs. 0.5 [0.1-1.1] mSv per year, p < 0.0001), respectively. CONCLUSIONS: Electrophysiologists' radiation-protective devices for occupational exposure are similar across European centers and in accordance with the applicable X-ray protection protocols, irrespective of the level of experience, number of monthly performed EP procedures, and gender.

Fluoroscopy usage in contemporary interventional electrophysiology: Insights from a European registry.

BACKGROUND: Fluoroscopy has been an essential part of every electrophysiological procedure since its inception. However, till now no clear standards regarding acceptable x-ray exposure nor recommendation how to achieve them have been proposed. HYPOTHESIS: Current norms and quality markers required for optimal clinical routine can be identified. METHODS: Centers participating in this Europe-wide multicenter, prospective registry were requested to provide characteristics of the center, operators, technical equipment as well as procedural settings of consecutive cases. RESULTS: Twenty-five centers (72% university clinics, with a mean volume of 526 ± 348 procedures yearly) from 14 European countries provided data on 1788 cases [9% diagnostic procedures (DP), 38% atrial fibrillation (AF) ablations, 44% other supraventricular (SVT) ablations, and 9% ventricular ablations (VT)] conducted by 95 operators (89% male, 41 ± 7 years old). Mean dose area product (DAP) and time was 304 ± 608 cGy*cm2 , 3.6 ± 4.8 minutes, 1937 ± 608 cGy*cm2 , 15.3 ± 15.5 minutes, 805 ± 1442 cGy*cm2 , 10.6 ± 10.7 minutes, and 1277 ± 1931 cGy*cm2 , 10.4 ± 12.3 minutes for DP, AF, SVT, and VT ablations, respectively. Seven percent of all procedures were conducted without any use of fluoroscopy. Procedures in the lower quartile of DAP were performed more frequently by female operators (OR 1.707, 95%CI 1.257-2.318, P = .001), in higher-volume center (OR 1.001 per one additional procedure, 95%CI 1.000-1.001, P = .002), with the use of 3D-mapping system (OR 2.622, 95%CI 2.053-3.347, P < .001) and monoplane x-ray system (OR 2.945, 95%CI 2.149-4.037, P < .001). CONCLUSION: Exposure to ionizing radiation varies widely in daily practice for all procedure. Significant opportunities for harmonization of exposure toward the lower range has been identified.

Standardized pulmonary vein isolation workflow to enclose veins with contiguous lesions: the multicentre VISTAX trial.

AIMS: To evaluate the safety and effectiveness of pulmonary vein isolation in paroxysmal atrial fibrillation (PAF) using a standardized workflow aiming to enclose the veins with contiguous and optimized radiofrequency lesions. METHODS AND RESULTS: This multicentre, prospective, non-randomized study was conducted at 17 European sites. Pulmonary vein isolation was guided by VISITAG SURPOINT (VS target ≥550 on the anterior wall; ≥400 on the posterior wall) and intertag distance (≤6 mm). Atrial arrhythmia recurrence was stringently monitored with weekly and symptom-driven transtelephonic monitoring on top of standard-of-care monitoring (24-h Holter and 12-lead electrocardiogram at 3, 6, and 12 months follow-up). Three hundred and forty participants with drug refractory PAF were enrolled. Acute effectiveness (first-pass isolation proof to a 30-min wait period and adenosine challenge) was 82.4% [95% confidence interval (CI) 77.4-86.7%]. At 12-month follow-up, the rate of freedom from any documented atrial arrhythmia was 78.3% (95% CI 73.8-82.8%), while freedom from atrial arrhythmia by standard-of-care monitoring was 89.4% (95% CI 78.8-87.0%). Freedom fromrepeat ablations by the Kaplan-Meier analysis was 90.4% during 12 months of follow-up. Of the 34 patients with repeat ablations, 14 (41.2%) demonstrated full isolation of all pulmonary vein circles. Primary adverse event (PAE) rate was 3.6% (95% CI 1.9-6.3%). CONCLUSIONS: The VISTAX trial demonstrated that a standardized PAF ablation workflow aiming for contiguous lesions leads to low rates of PAEs, high acute first-pass isolation rates, and 12-month freedom from arrhythmias approaching 80%. Further research is needed to improve the reproducibility of the outcomes across a wider range of centres.Clinical trial registration: ClinicalTrials.gov, number NCT03062046, https://clinicaltrials.gov/ct2/show/NCT03062046.

Direct Implantation of a Left Atrial Appendage Occluder During Cardiothoracic Surgery.

Surgical suture or exclusion of the left atrial appendage (LAA) is a commonly performed technique in patients undergoing cardiothoracic revascularization or valve repair, or both. However, incomplete surgical sealing of the LAA is not a rare phenomenon and strongly increases the risk for future cerebrovascular embolic events. We report the implantation of a Watchman LAA occluder (Boston Scientific, Natick, MA) during redo minimally invasive open heart surgery. This approach offers a new alternative for LAA occlusion in patients for whom a surgical procedure is scheduled.

The industrialization of ablation: a highly standardized and reproducible workflow for radiofrequency ablation of atrial fibrillation.

BACKGROUND OR PURPOSE: The purpose of this analysis was to report on efficacy of a standardized workflow for atrial fibrillation (AF) ablation using technology advances such as 3D imaging and contact force sensing in a real-world setting. METHODS: Consecutive AF ablations from 2014 to 2015 at a high-volume site in Belgium were included. The workflow consisted of a pre-specified procedure sequence including 3D modeling followed by radiofrequency encircling of the pulmonary veins (25 W posterior wall, 35 W anterior wall) with a THERMOCOOL SMARTTOUCH® Catheter guided by CARTO VISITAG™ Module (2.5 mm/5 s stability, 50% > 7 g) and ablation index (targets: 550 anterior wall, 400 posterior wall). Efficiency endpoints were procedure time, fluoroscopy time, and radiation dose. The primary effectiveness endpoint was freedom from atrial arrhythmia recurrence. RESULTS: A total of 605 paroxysmal AF (PAF) and 182 persistent AF (PsAF) patients were followed for 436 ± 199 days. Mean procedure times were short (PAF: 96.1 ± 26.2 min; PsAF: 109.2 ± 35.6 min) with most procedures (90.6% PAF; 81.3% PsAF) completed in ≤ 120 min. Minimal fluoroscopy was utilized (PAF: 6.1 ± 3.8 min, 5.9 ± 3.4 Gy*cm2; PsAF: 6.9 ± 4.7 min, 7.4 ± 4.9 Gy*cm2). Freedom from atrial arrhythmia recurrence was higher for PAF than PsAF patients (OR: 2.0, 95% CI: 1.4-2.9, p = 0.0003), but adjusted mean rates were high in both groups (81.0% vs. 67.9%). Rates were adjusted for prior ablation and age (at 65 years). CONCLUSION: AF ablation using a standardized workflow resulted in low procedure times and variability, with minimal fluoroscopy exposure. Long-term freedom from atrial arrhythmia recurrence was high in both PAF and PsAF populations.

Treatment of Atrial Fibrillation Using Ablation Index-Guided Contact Force Ablation: A Matching-Adjusted Indirect Comparison to Cryoballoon Ablation.

INTRODUCTION: Ablation Index, also known as VISITAG SURPOINT™, is a novel lesion-quality marker that improves outcomes in radiofrequency (RF) catheter ablation of atrial fibrillation (AF). There is no direct evidence on the comparative effectiveness of RF ablation with Ablation Index and cryoballoon (CB). The objective of the present study was to conduct a matching-adjusted indirect comparison (MAIC) using individual patient-level data (IPD) to compare the effectiveness of RF ablation with Ablation Index to that of CB on recurrence of atrial arrhythmias 12 months after catheter ablation in patients with paroxysmal AF (PAF). METHODS: Individual patient-level data for RF ablation with Ablation Index were obtained from two studies: Solimene et al. [J Interv Card Electrophysiol 54(1):9-15, 2019] and Hussein et al. [J Cardiovasc Electrophysiol 28(9):1037-1047, 2017]. Comparable CB studies identified from a systematic literature review were pooled. Prognostic variables for adjustment were ranked a priori by several practicing electrophysiologists. In the absence of a common treatment arm between the Ablation Index and CB studies, an unanchored MAIC was conducted. Primary analysis compared the Solimene et al. study to pooled CB studies. A secondary analysis compared pooled RF ablation with Ablation Index studies to pooled CB studies. Several scenario and sensitivity analyses were conducted. RESULTS: Primary analyses showed statistically significant reductions in the rate of arrhythmia recurrence with RF ablation with Ablation Index compared to CB in unmatched, unadjusted (HR 0.50, 95% CI 0.27-0.95) and matched (0.42, 0.21-0.86) analyses. Greater reductions in the rate of arrhythmia recurrence that favored RF ablation with Ablation Index were observed after matching and adjusting for age (0.41, 0.20-0.85), age and left ventricular ejection fraction (0.37, 0.16-0.88), and age, sex, and left ventricular ejection fraction (0.30, 0.13-0.71). Secondary and sensitivity analyses showed similar reductions. CONCLUSIONS: Radiofrequency ablation with Ablation Index was associated with reductions in recurrence of atrial arrhythmias at 12 months compared to CB in unmatched and unadjusted, matched, and matched and adjusted comparisons.

Pulmonary Vein Isolation With Very High Power, Short Duration, Temperature-Controlled Lesions: The QDOT-FAST Trial.

OBJECTIVES: This study sought to evaluate the safety and short-term performance of a novel catheter for very high power-short duration (vHPSD) ablation in the treatment of paroxysmal atrial fibrillation. BACKGROUND: The vHPSD catheter is a novel contact force-sensing catheter optimized for temperature-controlled radiofrequency ablation with microelectrodes and 6 thermocouples for real-time temperature monitoring; the associated vHPSD algorithm modulates power to maintain target temperature during 90 W, 4 s lesions. METHODS: QDOT-FAST (Clinical Study for Safety and Acute Performance Evaluation of the THERMOCOOL SMARTTOUCH SF-5D System Used With Fast Ablation Mode in Treatment of Patients With Paroxysmal Atrial Fibrillation) is a prospective, multicenter, single-arm study enrolling patients with symptomatic paroxysmal atrial fibrillation indicated for catheter-based pulmonary vein isolation. Primary endpoints were short-term effectiveness (confirmation of entrance block in all targeted pulmonary veins after adenosine/isoproterenol challenge) and short-term safety (primary adverse events). Participants were screened for silent cerebral lesions by magnetic resonance imaging. Patients were followed for 3 months post-ablation. RESULTS: A total of 52 patients underwent ablation and completed follow-up. Pulmonary vein isolation was achieved in all patients using the study catheter alone, with total procedure and fluoroscopy times of 105.2 ± 24.7 min and 6.6 ± 8.2 min, respectively. Most patients (n = 49; 94.2%) were in sinus rhythm at 3 months. Two primary adverse events were reported: 1 pseudoaneurysm; and 1 asymptomatic thromboembolism. There were no deaths, stroke, atrioesophageal fistula, pulmonary vein stenosis, or unanticipated adverse device effects. Six patients had identified silent cerebral lesions-all classified as asymptomatic without clinical or neurologic deficits. CONCLUSIONS: This first-in-human study of a novel catheter with optimized temperature control demonstrated the clinical feasibility and safety of vHPSD ablation. Procedure and fluoroscopy times were substantially lower than historical standard ablation with point-by-point catheters. (Clinical Study for Safety and Acute Performance Evaluation of the THERMOCOOL SMARTTOUCH SF-5D System Used With Fast Ablation Mode in Treatment of Patients With Paroxysmal Atrial Fibrillation [QDOT-FAST]; NCT03459196).

Feasibility of single position endoscopic laser balloon ablation for atrial fibrillation: The open 8 approach.

INTRODUCTION: Ablation without shaft repositioning may make the endoscopic laser ablation system (EAS) more like a single shot approach. We tested the feasibility of wide circumferential ablation (WCA; no carina ablation and no shaft repositioning) in an "open 8" pattern for pulmonary vein isolation (PVI). METHODS AND RESULTS: Forty-eight patients (n = 48, age 64.6 ± 12 years) with paroxysmal and persistent atrial fibrillation (AF) were referred to our center for PVI with the EAS. WCA for the lateral and septal pulmonary veins was attempted in all patients. If not feasible, individual full circular isolation of each pulmonary vein (iPVI) was performed. Additional lesions were applied if acute complete electrical isolation was not achieved on the first encirclement. Any documented episode of AF after a 1-month blanking period was registered as a recurrence. Bilateral WCA was feasible in 21 out of 48 patients (43.8%). Additional lesions for complete electrical isolation after the first-pass ablation were less in WCA compared with iPVI (P = 0.02). WCA was accomplished faster, with less applied energy at both lateral (P < 0.01) and septal side (P < 0.01). The mean follow-up of the patient population was 232 ± 150 days. AF recurrence occurred later in patients treated with WCA (315 ± 124 vs 110 ± 88 days, P = 0.008). CONCLUSIONS: WCA with the EAS is safe, at least moderately feasible and highly effective, if achieved. Compared with iPVI it may be less time consuming, results in less energy application, and suppresses AF more effectively.

Left atrial volume computed by 3D rotational angiography best predicts atrial fibrillation recurrence after circumferential pulmonary vein isolation.

Left atrium (LA) size is a well-studied predictor of atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI). Yet, there is still little agreement on the best imaging technique to size the LA, and on the most appropriate sizing parameter. Volumetric assessment of LA with three-dimensional rotational angiography (3DRA LA volume index) might be a valid alternative to the commonly used transthoracic echocardiography (TTE LA volume index). The aim of our study was to investigate whether LA volume by 3DRA at the time of PVI is able to predict the risk of atrial fibrillation recurrence. We analysed 352 consecutive patients with symptomatic paroxysmal or persistent atrial fibrillation referred for PVI to our Institution. In all patients, LA volume index (LAVI) was assessed by TTE and by 3DRA. Sinus rhythm was restored after PVI in 348 patients (99%). Average TTE-LAVI and 3DRA-LAVI were 37 ± 12 and 83 ± 18 ml/m2, respectively. At a median follow-up of 19 (12, 24) months, 27% of patients had AF recurrence after the first PVI. At the univariate analysis, persistent AF (p < 0.01), use of anti-arrhythmic drugs (AAD) (p < 0.05) and 3DRA-LAVI (p < 0.01) were significantly associated with AF recurrence. In contrast, none of the echocardiographic parameters considered, including TTE-LAVI, was associated with AF recurrence (p = 0.29). At the multivariate analysis, 3DRA-LAVI was the only independent predictor for AF recurrence (HR 1.01 [1.00-1.03], p = 0.017). Left atrial volume measured with 3DRA is superior to TTE assessment and to AF history in predicting atrial fibrillation recurrence after PVI.