Approach For Pulmonary Vein Isolation Research Articles

Does radiofrequency ablation procedural data improve the accuracy of identifying atrial fibrillation recurrence?

Radiofrequency ablation (RFA) using the CARTO 3D mapping system is a common approach for pulmonary vein isolation to treat atrial fibrillation (AF). Linkage between CARTO procedural data and patients' electronical health records (EHR) provides an opportunity to identify the ablation-related parameters that would predict AF recurrence. The objective of this study is to assess the incremental accuracy of RFA procedural data to predict post-ablation AF recurrence using machine learning model. Procedural data generated during RFA procedure were downloaded from CARTONET and linked to deidentified Mercy Health EHR data. Data were divided into train (70%) and test (30%) data for model development and validation. Automate machine learning (AutoML) was used to predict 1 year AF recurrence, defined as a composite of repeat ablation, electrical cardioversion, and AF hospitalization. At first, AutoML model only included Patients' demographic and clinical characteristics. Second, an AutoML model with procedural variables and demographical/clinical variables was developed. Area under receiver operating characteristic curve (AUROC) and net reclassification improvement (NRI) were used to compare model performances using test data. Among 306 patients, 67 (21.9%) patients experienced 1-year AF recurrence. AUROC increased from 0.66 to 0.78 after adding procedural data in the AutoML model based on test data. For patients with AF recurrence, NRI was 32% for model with procedural data. Nine of 10 important predictive features were CARTO procedural data. From CARTO procedural data, patients with lower contact force in right inferior site, long ablation duration, and low number of left inferior and right roof lesions had a higher risk of AF recurrence. Patients with persistent AF were more likely to have AF recurrence. The machine learning model with procedural data better predicted 1-year AF recurrence than the model without procedural data. The model could be used for identification of patients with high risk of AF recurrence post ablation.

Personalized pulmonary vein isolation with very high-power short-duration lesions guided by left atrial wall thickness: the QDOT-by-LAWT randomized trial.

Pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation (PAF) using very high-power short-duration (vHPSD) radiofrequency (RF) ablation proved to be safe and effective. However, vHPSD applications result in shallower lesions that might not be always transmural. Multidetector computed tomography-derived left atrial wall thickness (LAWT) maps could enable a thickness-guided switching from vHPSD to the standard-power ablation mode. The aim of this randomized trial was to compare the safety, the efficacy, and the efficiency of a LAWT-guided vHPSD PVI approach with those of the CLOSE protocol for PAF ablation (NCT04298177). Consecutive patients referred for first-time PAF ablation were randomized on a 1:1 basis. In the QDOT-by-LAWT arm, for LAWT ≤2.5 mm, vHPSD ablation was performed; for points with LAWT > 2.5 mm, standard-power RF ablation titrating ablation index (AI) according to the local LAWT was performed. In the CLOSE arm, LAWT information was not available to the operator; ablation was performed according to the CLOSE study settings: AI ≥400 at the posterior wall and ≥550 at the anterior wall. A total of 162 patients were included. In the QDOT-by-LAWT group, a significant reduction in procedure time (40 vs. 70 min; P < 0.001) and RF time (6.6 vs. 25.7 min; P < 0.001) was observed. No difference was observed between the groups regarding complication rate (P = 0.99) and first-pass isolation (P = 0.99). At 12-month follow-up, no significant differences occurred in atrial arrhythmia-free survival between groups (P = 0.88). LAWT-guided PVI combining vHPSD and standard-power ablation is not inferior to the CLOSE protocol in terms of 1-year atrial arrhythmia-free survival and demonstrated a reduction in procedural and RF times.

Regional variations in patient selection and procedural characteristics for cryoballoon ablation of atrial fibrillation in the cryo global registry

BackgroundCryoballoon ablation is a well-established anatomical approach for pulmonary vein isolation (PVI) in patients with atrial fibrillation (AF). Although widely adopted, regional variations in standards of care have not been well characterized.MethodsPatients with AF were enrolled in the Cryo Global Registry (NCT02752737) from May 2016 to Sept 2021 at 128 sites in 37 countries and treated with cryoballoon ablation according to local clinical practice. Baseline patient and procedural characteristics were summarized for 8 regions (Central Asia & Russia, East Asia, Europe, Middle East, North America, South Africa, South America, and Southeast Asia). Serious procedure-related adverse events (SAEs) were evaluated in a subset of patients with ≥ 7 days of follow-up.ResultsA total of 3,680 patients undergoing initial PVI for AF were included. Cryoballoon ablation was commonly performed in patients with paroxysmal AF. Mean age ranged from 47 ± 12 years in the Middle East to 64 ± 11 years in East Asia. Mean procedure time was ≤ 95 min in all regions. Average freeze duration ranged from 153 ± 41 s in Southeast Asia to 230 ± 29 s in Central Asia & Russia. Acute procedural success was ≥ 94.7% in all geographies. In 3,126 subjects with ≥ 7 days of follow-up, 122 procedure-related SAEs were reported in 111 patients (3.6%) and remained low in all regions. One procedure-related death was reported during data collection.ConclusionsDespite regional variations in patient selection and procedural characteristics, PVI using cryoballoon ablation was performed with high acute success and short procedural times around the world.Clinical trial registrationhttps://clinicaltrials.gov/ct2/show/NCT02752737Graphical

Pulsed field versus cryoballoon ablation of atrial fibrillation: A comparison of efficacy and safety in a 400 patient cohort

Abstract Funding Acknowledgements Type of funding sources: Private company. Main funding source(s): Boris Schmidt, KR Julian Chun and Stefano Bordignon received speaking honoraria from Medtronic and Boston Scientific Background The cryoballoon (CB) is one of the most commonly used single shot devices for pulmonary vein isolation in patients with atrial fibrillation (AF). Pulsed field ablation (PFA) is a new non-thermal, tissue selective approach for pulmonary vein isolation. Purpose We sought to compare procedural safety and efficacy of these single shot ablation techniques. Methods Consecutive AF patients (paroxysmal / persistent AF) who underwent CB based pulmonary vein isolation (PVI) between November 2020 and February 2022 were enrolled and compared with patients who underwent PFA ablation in the same time period. Patients that underwent ablation beyond PVI (except for cavo-tricuspid isthmus ablation) were excluded. CB PVI was performed using the second-generation CB (CB 28 mm) with 240 sec based freeze protocol and bonus freeze delivery in case of time-to-isolation (TTI) &amp;gt;75 sec. PFA was performed using the Farawave catheter, using the 31 or 35 mm device. All procedures were performed under deep sedation. Results Data from 400 consecutive patients were collected. Most baseline characteristics like age (CB: 67,5 ± 15,3; PFA: 68,4 ± 11; p=0,49), BMI (CB: 28,6 ± 6,3; PFA: 27,9 ± 5,6; p=0,27) and gender (male) (CB: 54%; PFA: 59%; p=0,31) were comparable between the two groups. All PVIs were successfully completed. In 98% (196) of patients in the CB group and 100% (200) in the PFA group, PVI was performed using solely CB or PFA respectively, meaning additional touch up ablation was only needed in 4 CB patients (2%; p=0,044) and 4 veins. Procedure time was significantly shorter in the PFA group (CB: 53 ± 15,3 minutes; PFA: 36,8 ± 13,5 minutes; p&amp;lt;0,001), whereas no difference in fluoroscopy time (CB: 8,1 ± 4,4 minutes; PFA: 7,8 ± 3,3 minutes; p=0,2) was observed. The rate of concomitant CTI-ablation was equal in both groups (CB: 1,5%; PFA: 1,5%; p=1,0). Complication rate was 3,5% with PFA and 6,5% in CB (p=0,17), a difference mostly driven by persistent phrenic nerve palsies (CB: 1,5%; PFA: 0%; p=0,08). All patients are out of the blanking period. There were 80 recurrences in blanking time (CB: 41; PFA: 39; p=0,8). In CB 19,5% of blanking time recurrences were atrial tachycardias compared to 35,9% in PFA (p=0,1). The average time to blanking recurrence was 14,1 ± 21,5 days in CB and 20,5 ± 23,2 in PFA (p=0,2). In total, there were 7 repeat procedures (4 in CB and 3 in PFA; p=0,7) during blanking time due to arrhythmias, despite of antiarrhythmic drugs and/or cardioversion. At the time of this analysis, the first hundred patients in each group reached one-year follow-up. Recurrence free survival after one year for patients with PAF was 82,6% in CB and 80,0% in PFA. In patients with persistent AF it was 70,8% in CB and 67,8% in PFA. Conclusion Cryoballoon and pulsed field ablation are both highly effective and safe techniques for PVI. PFA had a shorter procedure time, whereas the one year follow up was similar for both techniques.

P104 LASER BALLOON APPROACH FOR PULMONARY VEIN ISOLATION IN MARFAN SYNDROME

Abstract Background Marfan syndrome (MFS) is an autosomal dominant disorder of the connective tissue and it’s associated with an increased incidence of atrial fibrillation (AF), due to scar–mediated processes and sites of atrial ectopy. Limited data exist regarding ablation techniques in these patients. The frailty of atrial walls correlated to connective disease makes the ablation challenging with an increased risk of complications. Laser–balloon (LB) approach for pulmonary vein isolation (PVI) could be a promising strategy due to the possibility to ablate a large volume of tissue with a single application of energy, short procedure times, and real–time monitoring of balloon–tissue contact. We present a case in which LB technology was applied for PVI in an MFS patient Clinical case A 44–year–old woman with MFS and paroxysmal AF underwent PVI. The echocardiographic examination showed mild aortic and mitral valve regurgitation, the first due to a slight dilation of the aortic root, the latter associated with mitral valve prolapse. Atrial volume was normal. No other comorbidities were present. The procedure was executed in general anesthesia. A decapolar catheter was inserted in the coronary sinus and used later to stimulate the phrenic nerve during the ablation of the right pulmonary veins (Fig.1C). Left atria (LA) was reached after an ultrasound–guided transeptal puncture. High–density mapping of the LA was performed to assess the number and geometry of PVs (Fig.1A). A LB catheter was used to perform laser ablation at the level of PV antrum, delivering 13 W in automatic rapid mode in regions with optimal contact and 5.5 W in areas with more represented blood–tissue interface. LA mapping after ablation assessed the effective isolation of pulmonary veins (Fig.1B). No complications occurred during the procedure. Conclusion a laser–balloon approach for PVI in MFS patients seems feasible and safe. To our knowledge, this is the first application of this technology on MFS patients. Larger data are needed to confirm our findings.

Novel protocol for optimal utilization of HPSD approach for pulmonary vein isolation.

The efficiency of pulmonary vein isolation (PVI) depends on the durability of RF lesions. Recent studies documented sustained continuity of ablation lines, improvements in durability, and expected clinical outcomes through altered settings in duration and power. However, the ablation strategy has not been adapted to this new approach and different biophysics of lesion formation. The aim of this study was to demonstrate that by adjusting the ablation approach to the broader geometry of lesions by increasing the minimal spacing between adjacent RF, a further significant reduction of procedural time while maintaining sufficient long-term outcomes is achievable. The presented study was a prospective, observational multi-center trial. The periprocedural data were compared with data from a consecutively collected historical cohort. In total, 196 patients were included (mean age 62 ± 11 years, male 64.3%). Procedural duration, RF time, and LA dwelling time were significantly shorter in the HPSD group compared with the standard group (73 ± 26 min vs. 98 ± 36 min, p < .001; 14 ± 7 min vs. 33 ± 12 min, p < .001; and 59 ± 21 min vs. 77 ± 32 min, p < .001, respectively). Mean AF-free survival in the first year of follow-up was 304 ± 14 days in the HPSD group versus 340 ± 10 days in the standard group (log-rank p = .403). There were no statistically significant differences in the complication rates between the groups. Increasing the minimal distance between individual application points simplifies AF ablation and further reduces procedure time without negative effects on efficacy and safety. Larger studies are needed to optimally utilize this approach.

Regional variations in patient selection and procedural characteristics for cryoballoon ablation of atrial fibrillation

Abstract Background Cryoballoon ablation is a well-established anatomical approach for pulmonary vein isolation (PVI) in patients with atrial fibrillation (AF). Although widely adopted, regional variations in standards of care have not been well characterized. Purpose To evaluate regional variations in patient selection and procedural characteristics for PVI with cryoablation in the Cryo Global Registry (NCT02752737). Methods Patients with AF were enrolled from May 2016 to October 2021 at 128 sites in 37 countries. Patients were treated with cryoballoon ablation according to local clinical practice. Baseline subject and procedural characteristics were summarized for 8 regions (Central Asia and Russia, East Asia, Europe, Middle East, North America, South Africa, South America, and Southeast Asia). Procedure-related serious adverse events (SAEs) were evaluated in a subset of patients with ≥7 days of follow-up. Results A total of 3680 patients undergoing initial PVI for AF were included. Cryoballoon ablation was more commonly performed in patients with paroxysmal vs. persistent AF in all regions, and in males vs. females in all regions except Central Asia and Russia. Mean age ranged from 47±12 in the Middle East to 64±11 in East Asia. Regional variations were observed in the proportion of patients with common AF comorbidities undergoing cryoablation (Table 1). Median procedure time ranged from 61 (49–68) minutes in Central Asia and Russia to 95 (76–120) minutes in Southeast Asia. Median fluoroscopy time was ≤20 minutes in all regions. The use of 3D mapping was relatively uncommon except in North America (63.3%). Large variation was observed in the use of esophageal monitoring, whereas phrenic nerve monitoring was used in ≥97.7% of cases in all regions (Table 2). Same-day discharge was uncommon except in North and South America (37.8% and 26.5% of cases, respectively). Average freeze duration ranged from 153±41 seconds in Southeast Asia to 230±29 seconds in Central Asia and Russia. Mean number of applications per vein ranged from 1.2±0.4 in Central Asia and Russia to 2.1±1.0 in North America. Acute procedural success was ≥94.7% in all geographies and focal radiofrequency touch-up was required in ≤13.0% of cases. In 3126 subjects with ≥7 days of follow-up, 122 procedure-related SAEs were reported in 111 patients (3.6%), and 1 procedure-related death was reported during data collection. Conclusion(s) Despite regional variations in patient selection and procedural characteristics, PVI using cryoballoon ablation is performed with high acute success and short procedural times around the world. Funding Acknowledgement Type of funding sources: Private company. Main funding source(s): Medtronic, Inc.

Atrial fibrillation ablation from above

Pulmonary vein isolation is a well-established therapy for symptomatic atrial fibrillation. The standard access for left atrial procedures is a transfemoral approach. Rarely, access to the heart from an inferior approach is not feasible due to congenital or acquired interruption of the inferior vena cava. In the present case, we discuss relevant aspects and technical issues related to the superior approach for pulmonary vein isolation.

2-year outcomes of phased radiofrequency ablation for atrial fibrillation with the second-generation PVAC Gold ablation catheter

PurposeThe second-generation multi-electrode catheter, PVAC Gold, was designed to improve the safe delivery of phased radiofrequency energy using a “single shot” approach for pulmonary vein isolation (PVI), while retaining efficacy. This large registry presents long-term performance in a daily practice setting.MethodsA total of 1011 patients undergoing first time ablation for atrial fibrillation (AF) using PVAC Gold were included, 639 patients with PVI for paroxysmal AF (PAF PVI) and 372 patients with persistent or long-standing persistent AF, divided into 175 patients receiving PVI only (PersAF PVI) and 197 patients receiving PVI with additional substrate ablation (PersAF PVI +).ResultsAt 24-month follow-up, single procedure freedom from atrial tachyarrhythmia (ATA) was 58% (368/639) in the PAF PVI group, 44% (77/175) in the PersAF PVI group, and 29% (57/197) in the PersAF PVI + group. Allowing one repeat procedure in 33% of patients, 76%, 65%, and 54% were free from ATA at 24 months, respectively. Pulmonary vein reconnection was observed in 98% of patients with recurrent arrhythmia after PVI.ConclusionsAlthough phased RF ablation with PVAC Gold is quick and safe, the efficacy outcomes are modest compared to current mainstream ablation strategies.

B-PO05-095 USE OF RADIOFREQUENCY ABLATION CATHETER IN CRYOBALLOON PULMONARY VEIN ISOLATION - A TWO HOSPITAL SYSTEM LOCAL EXPERIENCE

Pulmonary vein isolation (PVI) with catheter ablation is a preferred method for symptom and rhythm control in patients with atrial fibrillation (AF). Both Cryoballoon and radiofrequency (RF) ablation are commonly used to achieve PVI. Prior studies have suggested that approximately 14.1 % of Cryoballoon ablation also require RF catheter to complete PVI. To assess the usage of RF catheter in our hospital system for cases where cryoballoon ablation was used as primary approach for PVI. We performed a retrospective analysis of 378 patients with either paroxysmal or persistent AF who underwent PVI at two Methodist LeBonheur Healthcare system hospitals in Memphis TN from January 2013 to June 2020. Patient demographics and PVI procedure details were obtained using electronic medical records. Data was compiled using Redcap and statistical analysis was performed using SPSS version 27. A total of 167 AF patients underwent cryoballoon ablation as a primary approach. 127 patients had paroxysmal AF, 37 patients had persistent AF, 2 patients had longstanding persistent AF and one AF type was not classified. The mean age was 61.7 +/- 11 years and there were 112 males (67.1%). In 62 patients (37.1%) RF ablation was required to complete PVI. In additional 44 patients (26.4%), RF catheter was used to perform additional linear or complex fractionated atrial electrograms ablations during an index procedure. The total usage of RF catheter was 63.5% in the index Cryoballoon AF ablation. In this study of our hospital system comprising of two hospitals performing AF ablation, RF ablation was employed in a majority of patients where cryoballoon ablation was the primary approach.

The feasibility and effectiveness of a streamlined single-catheter approach for radiofrequency atrial fibrillation ablation.

BackgroundCatheter ablation for atrial fibrillation (AF) traditionally requires the use of circular mapping catheter (CMC) for pulmonary vein isolation (PVI). This study aimed to assess the feasibility and effectiveness of a CMC‐free approach for AF ablation performed by a contiguous optimized (CLOSE) ablation protocol.MethodsA CLOSE‐guided and CMC‐free PVI protocol with a single transseptal puncture was attempted in 67 patients with AF. Left atrial (LA) CARTO voltage mapping was performed with the ablation catheter pre‐ and postablation to demonstrate entry block into the pulmonary veins, and pacing maneuvers were used to confirm exit block.ResultsThe CMC‐free approach was successful in achieving PVI in 66 (98.5%) cases, with procedure time of 148 ± 32 minutes, ablation time of 27.5 ± 5.7 minutes, and fluoroscopy time of 7.8 ± 1.0 minutes. First‐pass PVI was seen in 58(86.5%) patients, and pacing maneuvers successfully identified the residual gap in eight of the other nine cases. No complication was observed. At 12 months follow‐up, 60 (89.6%) patients remained free from AF. The CMC‐free approach resulted in a cost saving of £47,190.ConclusionA CMC‐free CLOSE‐guided PVI approach is feasible, safe, and cost‐saving, and is associated with excellent clinical outcomes at 1 year.

Acute success and safety of the second-generation PVAC GOLD phased RF ablation catheter for atrial fibrillation

PurposeThe second-generation multi-electrode catheter, pulmonary vein ablation catheter (PVAC) GOLD, was designed to improve the delivery of phased radiofrequency energy and reduce procedure times using a ‘single-shot’ approach for pulmonary vein isolation (PVI), while retaining efficacy and safety. This large registry presents acute success rates and safety outcomes in a daily practice setting.MethodsA total of 1017 patients undergoing first-time ablation for atrial fibrillation (AF) using PVAC GOLD were included, 644 patients with paroxysmal AF and 373 patients with non-paroxysmal AF, divided into 175 patients receiving PVI only and 198 patients receiving PVI with additional substrate modification.ResultsHigh and comparable percentages of successful PVI could be achieved in all groups (98%, 95% and 99%; p = 0.108). The median total procedure time for all groups was 90 min [70–100]. As expected, the total procedure, ablation and fluoroscopy time were significantly longer in the PVI + substrate modification group compared with the PVI-only cases (all p < 0.001), but not between the PVI-only groups (p = 0.306, p = 0.088, p = 0.233, respectively). A total of 44 complications were observed in 43 patients (4.2%). Major complications were seen in 19 patients (1.87%) and non-major procedure–related complications were seen in 25 patients (2.46%). Complications leaving permanent sequelae were rare and occurred in only four patients (0.39%). Complications did not differ between groups (p = 0.199, p = 0.438, p = 0.240 and p = 0.465 respectively).ConclusionPVAC GOLD performs successful PVI, while reducing procedure times and retaining safety for paroxysmal, persistent and long-standing persistent AF. Safety was unaffected by additional substrate modification.

Pulmonary vein isolation using ablation index vs. CLOSE protocol with a surround flow ablation catheter.

Pulmonary vein isolation (PVI) using ablation index (AI) incorporates stability, contact force (CF), time, and power. The CLOSE protocol combines AI and ≤6 mm interlesion distance. Safety concerns are raised about surround flow ablation catheters (STSF). To compare safety and effectiveness of an atrial fibrillation (AF) ablation strategy using AI vs. CLOSE protocol using STSF. First cluster was treated using AI and second cluster using CLOSE. Procedural data, safety, and recurrence of any atrial tachycardia (AT) or AF >30 s were collected prospectively. All Classes 1c and III anti-arrhythmic drugs (AAD) were stopped after the blanking period. In total, all 215 consecutive patients [AI: 121 (paroxysmal: n = 97), CLOSE: n = 94 (paroxysmal: n = 74)] were included. Pulmonary vein isolation was reached in all in similar procedure duration (CLOSE: 107 ± 25 vs. AI: 102 ± 24 min; P = 0.1) and similar radiofrequency time (CLOSE: 36 ± 11 vs. AI: 37 ± 8 min; P = 0.4) but first pass isolation was higher in CLOSE vs. AI [left veins: 90% vs. 80%; P < 0.05 and right veins: 84% vs. 73%; P < 0.05]. Twelve-month off-AAD freedom of AF/AT was higher in CLOSE vs. AI [79% (paroxysmal: 85%) vs. 64% (paroxysmal: 68%); P < 0.05]. Only four patients (2%) without recurrence were on AAD during follow-up. Major complications were similar (CLOSE: 2.1% vs. AI: 2.5%; P = 0.87). The CLOSE protocol is more effective than a PVI approach solely using AI, especially in paroxysmal AF. In this off-AAD study, 79% of patients were free from AF/AT during 12-month follow-up. The STSF catheter appears to be safe using conventional CLOSE targets.

Evaluation of Entrance Skin Dose to Patients Undergoing Catheter Ablation Procedures for Atrial Fibrillation : Influence of Approach for Pulmonary Vein Isolation

Evaluation of Entrance Skin Dose to Patients Undergoing Catheter Ablation Procedures for Atrial Fibrillation : Influence of Approach for Pulmonary Vein Isolation

Stand-Alone Pulmonary Vein Isolation Versus Pulmonary Vein Isolation With Additional Substrate Modification as Index Ablation Procedures in Patients With Persistent and Long-Standing Persistent Atrial Fibrillation: The Randomized Alster-Lost-AF Trial (Ablation at St. Georg Hospital for Long-Standing Persistent Atrial Fibrillation).

Pulmonary vein isolation (PVI) for persistent atrial fibrillation is associated with limited success rates and often requires multiple procedures to maintain stable sinus rhythm. In the prospective and randomized Alster-Lost-AF trial (Ablation at St. Georg Hospital for Long-Standing Persistent Atrial Fibrillation), we sought to assess, in patients with symptomatic persistent or long-standing persistent atrial fibrillation, the outcomes of initial ablative strategies comprising either stand-alone PVI (PVI-only approach) or a stepwise approach of PVI followed by complex fractionated atrial electrogram ablation and linear ablation (Substrate-modification approach). Patients were randomized 1:1 to stand-alone PVI or PVI plus substrate modification. The primary study end point was freedom from recurrence of any atrial tachyarrhythmia, outside a 90-day blanking period, at 12 months. A total of 124 patients were enrolled, with 118 patients included in the analysis (61 in the PVI-only group, 57 in the Substrate-modification group). Atrial tachyarrhythmias recurred in 28 PVI-only group patients and 24 Substrate-modification group patients, for 1-year freedom from tachyarrhythmia recurrence after a single ablation procedure of 54% (95% confidence interval, 43%-68%) in the PVI-only and 57% (95% confidence interval, 46%-72%) in the Substrate-modification group (P=0.86). Twenty-four patients in the PVI-only group (39%) and 18 in the Substrate-modification group (32%) were without arrhythmia recurrence and off antiarrhythmic drug therapy at the end of the 12-month follow-up. In patients with persistent and long-standing persistent atrial fibrillation, no significant difference was observed in 12-month freedom from atrial tachyarrhythmias between an index ablative approach of stand-alone PVI and a stepwise approach of PVI plus complex fractionated atrial electrogram and linear ablation. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00820625.

Contact-force guided single-catheter approach for pulmonary vein isolation: Feasibility, outcomes, and cost-effectiveness

For conventional ablation of paroxysmal atrial fibrillation (AF), an ablation catheter in conjunction with a circular mapping catheter (CMC) is typically used for pulmonary vein isolation (PVI). The purpose of this study was to evaluate an approach for PVI with a single contact-force (CF) ablation catheter in terms of procedural reliability, outcomes, and cost-effectiveness. One hundred consecutive patients with paroxysmal AF were included in the study. Fifty patients (study group) underwent a CF-guided single-catheter approach, whereby PVI was demonstrated when sequential pacing at 9 equidistant points within the lesion set (carina included) failed to capture the left atrium. For confirmation, PVI was verified with a CMC. In comparison, 50 patients (control group) underwent a conventional PVI ablation guided by a CMC. Procedure time (101 ± 17 minutes vs 107 ± 15 minutes, P = .11), ablation time (24.2 ± 7.1 minutes vs 22.6 ± 8.8 minutes, P = .37), fluoroscopy time (5.6 ± 2.2 minutes vs 8.3 ± 3.4 minutes, P = .09), and applied CF (17.8 ± 2.6 g vs 18 ± 2.8 g, P = .72) did not reach statistical difference between the study and control groups. CF-guided single-catheter ablation achieved successful PVI in 98% of the study group and a 31% reduction in cost. At 1-year follow-up, sinus rhythm maintenance rate was similar in both groups (86% vs 84%, P = .78). In paroxysmal AF, a CF-guided single-catheter technique is an effective method for PVI, yielding substantial cost savings and clinical results similar to a conventional approach.

Acute and Mid-Term Results after Pulmonary Veins Isolation Using a Novel Circular Irrigated Multielectrode Mapping and Ablation Catheter (nMARQ)

Background: Pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) ablation in both paroxysmal and persistent AF. However, this procedure is still challenging and time consuming. Objective: The aim of this study was to present our approach for PVI using a novel circular irrigated multielectrode mapping and ablation catheter (nMARQTM) and to present acute and mid-term results. Methods: The study included 31 consecutive patients with symptomatic AF (4 had persistent and 27 had paroxysmal AF) who underwent PVI using the nMARQTM catheter. Circular ablation was guided by CT image integrated into fast anatomical map and by intra cardiac echo. Isolation of pulmonary veins was identified using the nMARQTM catheter if it was possible to advance it into the veins, otherwise Lasso catheter was used. Patients were followed up to 20 months. Results: PVI was achieved in 119 (98%) out of 121 pulmonary veins identified, and final PVI was obtained in 30 (97%) out of 31 patients. Lasso catheter was needed for PVI confirmation in 16 (52%) patients. Touch up ablation using standard catheter guided by Lasso catheter was needed in 4 (13%) patients. Pericardial tamponade occurred in 1 patient who was treated with pericardiocentesis. No other major complications were detected. During follow-up (mean 15.9 ± 3.6 months, range 9 - 20 months), 4 (13%) patients had recurrence of atrial tachyarrhythmia. Conclusion: PVI using the novel nMARQTM catheter is safe with good acute and mid-term efficacy. Long term follow up trials are needed.

Advances in cryoballoon technology: benefits and risks in daily practice

Cryoballoon ablation is nowadays a standard approach for pulmonary vein isolation in symptomatic atrial fibrillation. The second generation cryoballoon was introduced in 2012 and modifications and enhancement to the system promised a higher efficiency. A comprehensive overview of advances in cryoballoon ablation is provided and the consequences for daily practice are described based on a PubMed literature search, taking into account own experiences. Advances in cryoballoon ablation result in a significantly higher efficiency. To maintain the overall safety of the procedure and to avoid phrenic nerve palsy and esophageal lesions, special care needs to be taken by following some safety aspects and cut-off criteria. More data are necessary to clarify if recommendations for cryoenergy titration with the new balloon are reasonable. Ongoing prospective studies comparing cryoballoon and radiofrequency (RF) ablation will give answers to the question which energy source is more favorable, and upcoming studies will evaluate the impact of cryoballoon ablation as a first line treatment option.

Single, remote-magnetic catheter approach for pulmonary vein isolation in patients with paroxysmal and non-paroxysmal atrial fibrillation

BackgroundThe aim of the study was to investigate the safety and efficacy of a single, remote-magnetic catheter navigation system (MNS) for pulmonary vein isolation (PVI). MethodsA total of 107 PVI procedures in 71 patients with paroxysmal (32%), persistent (38%) and longstanding-persistent (30%) atrial fibrillation (AF) were analyzed. A wide area circumferential radiofrequency ablation PVI was performed with either an 8mm MNS (first 35 procedures) or an irrigated MNS (last 36 procedures) catheter. Electrical isolation was confirmed with circular pacing/sensing using the MNS catheter and a coronary sinus catheter. Our follow-up strategy in the first year and upon symptoms thereafter was: clinical check plus 12-lead ECG (100%) and 24h-ECG recordings (76%) at 3month intervals, trans-telephonic ECG (79%) twice daily and upon symptoms (4weeks every 3months), or ECG monitoring via implanted devices (9%). ResultsThe mean procedure time at 1st PVI was 247±61min, and mean fluoroscopy time was 44±18min. The overall complication rate was 2%. Success rates did not differ at the 1st PVI regarding catheter type (p=0.931) but were dependent on history of AF: patients with paroxysmal AF had the highest success rates of 58% and 29% after 1 and 3years of follow-up, respectively (p=0.0084). ConclusionPVI with a single MNS catheter is safe and is associated with short fluoroscopy exposition. Despite a rigorous follow-up strategy success rates favorably compare with recently published data on hand-held PVI. Thus, multipolar catheters or a 2nd trans-septal puncture may not be mandatory.

Persistent iatrogenic atrial septal defect after a single-puncture, double-transseptal approach for pulmonary vein isolation using a remote robotic navigation system: results from a prospective study

Persistent iatrogenic atrial septal defect (iASD) after transseptal puncture for pulmonary vein isolation (PVI) has been described recently as a complication of PVI. No data exists evaluating systematically the incidence and clinical implications of iASDs after PVI using a remote robotic navigation system (RNS) with sheaths with a distinct larger outer diameter. In this prospective study, 40 patients with either paroxysmal (n = 22, 55%) or persistent symptomatic atrial fibrillation were treated with circumferential PVI using an RNS. In all patients, a single-puncture, double-transseptal approach was used to access the left atrium. Transoesophageal echocardiography was performed before and the day after PVI as well as after a 3 and 6 months follow-up (FU). The day after ablation an iASD was detected in 38 of 40 (95%) patients with a mean diameter of 3.45 +/- 1.5 mm. At 6-month FU, the iASDs were closed in 30 of 39 (78.9%) patients. During the 6-month FU period, no patient died or suffered from cerebral or cardiac embolism. After a single-puncture, double-transseptal approach for PVI using the RNS, iASDs show a high spontaneous closure rate of 78.9% after a 6-month FU period. Persistent iASDs following PVI with the RNS are not associated with an increased rate of paradoxical embolism or with relevant shunting.