Initial experience, safety, and feasibility using remote access or onsite technical support for complex ablation procedures: results of the REMOTE study.

Aims: Electroanatomical mapping (EAM) systems are essential for the treatment of cardiac arrhythmias. The EAM system is usually operated by qualified staff or field technical engineers from the control room. Novel remote support technology allows for remote access of EAM via online services. Remote access increases the flexibility of the electrophysiological lab, reduces travel time, and overcomes hospital access limitations especially during the COVID-19 pandemic. Here, we report on the feasibility and safety of EAM remote access for cardiac ablation procedures. Methods and results: Mapping and ablation were achieved by combining the EnsiteX™ EAM system and the integrated Ensite™ Connect Remote Support software, together with an integrated audiovisual solution system for remote support (Medinbox). Communication between the operator and the remote support was achieved using an incorporated internet-based common communication platform (Zoom™), headphones, and high-resolution cameras. We investigated 50 remote access-assisted consecutive electrophysiological procedures from September 2022 to February 2023 (remote group). The data were compared with matched patients (n = 50) with onsite support from the control room (control group). The median procedure time was 100 min (76, 120; remote) vs. 86 min (60, 110; control), P = 0.090. The procedural success (both groups 100%, P = 0.999) and complication rate (remote: 2%, control: 0%, P = 0.553) were comparable between the groups. Travel burden could be reduced by 11 280 km. Conclusion: Remote access for EAM was feasible and safe in this single-centre study. Procedural data were comparable to procedures with onsite support. In the future, this new solution might have a great impact on facilitating electrophysiological procedures.

Venous vascular closure system vs. figure-of-eight suture following atrial fibrillation ablation: the STYLE-AF Study.

AIMS: Simplified ablation technologies for pulmonary vein isolation (PVI) are increasingly performed worldwide. One of the most common complications following PVI are vascular access-related complications. Lately, venous closure systems (VCSs) were introduced into clinical practice, aiming to reduce the time of bed rest, to increase the patients' comfort, and to reduce vascular access-related complications. The aim of the present study is to compare the safety and efficacy of using a VCS to achieve haemostasis following single-shot PVI to the actual standard of care [figure-of-eight suture and manual compression (MC)]. METHODS AND RESULTS: This is a prospective, multicentre, randomized, controlled, open-label trial performed at three German centres. Patients were randomized 1:1 to undergo haemostasis either by means of VCS (VCS group) or of a figure-of-eight suture and MC (F8 group). The primary efficacy endpoint was the time to ambulation, while the primary safety endpoint was the incidence of major periprocedural adverse events until hospital discharge. A total of 125 patients were randomized. The baseline characteristics were similar between the groups. The VCS group showed a shorter time to ambulation [109.0 (82.0, 160.0) vs. 269.0 (243.8, 340.5) min; P < 0.001], shorter time to haemostasis [1 (1, 2) vs. 5 (2, 10) min; P < 0.001], and shorter time to discharge eligibility [270 (270, 270) vs. 340 (300, 458) min; P < 0.001]. No major vascular access-related complication was reported in either group. A trend towards a lower incidence of minor vascular access-related complications on the day of procedure was observed in the VCS group [7 (11.1%) vs. 15 (24.2%); P = 0.063] as compared to the control group. CONCLUSION: Following AF ablation, the use of a VCS results in a significantly shorter time to ambulation, time to haemostasis, and time to discharge eligibility. No major vascular access-related complications were identified. The use of MC and a figure-of-eight suture showed a trend towards a higher incidence of minor vascular access-related complications.

Pulmonary vein isolation durability after very high-power short-duration ablation utilizing a very-close protocol - The FAST AND FURIOUS redo study.

Background: Very high-power short-duration (vHP-SD) radiofrequency (RF) ablation of atrial fibrillation (AF) treatment by pulmonary vein isolation (PVI) aims for safer, more effective and faster procedures. Although acute efficacy and safety for PVI was recently shown data on chronic PVI durability is limited. Here chronic PVI durability was evaluated during repeat electrophysiological procedures in patients after initial vHP-SD and conventional RF based PVI. Methods: A total of 25 consecutive patients with repeat left atrial procedures after initial vHP-SD based PVI were included in this study. Twenty-five patients with previous conventional RF based PVI and repeat left atrial procedures served as control (control group). Results: For index procedures the median RF time was 328 (277, 392) seconds (vHP-SD) and 1470 (1310, 1742) seconds (control); p < 0.001, the median procedure time was 55 (53, 68) minutes (vHP-SD) and 110 (94, 119) (control); p < 0.001). First pass isolation rate was 84 % (vHP-SD) and 88 % (control, p = 0.888). No differences for severe adverse events (vHP-SD: 1/25, 4 % vs. control: 0/25, 0 %; p = 0.676 were detected.Chronic durability of all PVs was assessed in vHP-SD: 16/25 (64 %) and control: 8/25 (32 %) patients (p = 0.023) and vHP-SD: 81 % and control: 62 % of PVs were found to be isolated (p = 0.003). For right PVs vHP-SD: 84 % vs. control: 60 % of PVs (p < 0.001) and for left PVs vHP-SD: 78 % vs. control: 64 % (p = 0.123) were found to be isolated. Conclusions: PVI solely utilizing vHP-SD via a very close-protocol provides fast, safe and effective acute PVI. High rates of chronically isolated pulmonary veins have been detected.

Impact of pulsed field ablation on intraluminal esophageal temperature.

INTRODUCTION: Atrio-esophageal fistula after esophageal thermal injury (ETI) is one of the most devastating complications of available energy sources for atrial fibrillation (AF) ablation. Pulsed field ablation (PFA) uses electroporation as a new energy source for catheter ablation with promising periprocedural safety advantages over existing methods due to its unique myocardial tissue sensitivity. In preclinical animal studies, a dose-dependent esophageal temperature rise has been reported. In the TESO-PFA registry intraluminal esophageal temperature (TESO) changes in a clinical setting are evaluated. METHODS: Consecutive symptomatic AF patients (62 years, 67% male, 61% paroxysmal AF, CHA2 DS2 Vasc Score 2) underwent first-time PFA and were prospectively enrolled into our registry. Eight pulse trains (2 kV/2.5 s, bipolar, biphasic, x4 basket/flower configuration each) were delivered to each pulmonary vein (PV). Two extra pulse trains per PV in flower configuration were added for wide antral circumferential ablation. Continuous intraluminal esophageal temperature (TESO) was monitored with a 12-pole temperature probe. RESULTS: Median TESO change was statistically significant and increased by 0.8 ± 0.6°C, p < .001. A TESO increase ≥ 1°C was observed in 10/43 (23%) patients. The highest TESO measured was 40.3°C. The largest TESO difference (∆TESO) was 3.7°C. All patients remained asymptomatic considering possible ETI. No atrio-esophageal fistula was reported on follow-up. CONCLUSION: A small but significant intraluminal esophageal temperature rise can be observed in most patients during PFA. TESO rise over 40°C is rare. The clinical implications of the observed findings need to be further evaluated.

Pulsed Field Ablation-Based Pulmonary Vein Isolation Using a Simplified Single-Access Single-Catheter Approach　- The Fast and Furious PFA Study.

BACKGROUND: Pulsed field ablation (PFA) is a non-thermal energy source with promising safety and efficacy advantages. We aimed to develop a convenient, safe, effective and fast method of pulmonary vein isolation (PVI) utilizing a penta-spline PFA catheter via a single femoral vein and a venous closure system.Methods and Results: Consecutive patients (n=50; mean age: 63.6±10.7 years, 38% female) presenting with AF (paroxysmal AF: 56%) underwent first-time PVI via PFA. A single ultrasound-guided femoral vein puncture and a single transseptal puncture were used. After PVI using the penta-spline PFA catheter, extra pulse trains were added to the posterior wall for wide antral circumferential ablation. A venous closure system was used and a Donati suture was performed. The pressure bandage was removed after 1 h. A total of 196 PVs were identified and isolated with PFA only. The mean procedural time was 27.4±6.6 min, and the mean dwelling time was 14.4±5.5 min. Time to ambulation was 3.3±3.1 h. No severe complications occurred. During a mean follow-up of 6.5±2.1 months, 41/50 patients (82%) remained in sinus rhythm. CONCLUSIONS: The combination of a single venous puncture, single transseptal puncture approach using PFA and vascular closure device resulted in a 100% rate of acute PVI and an extraordinarily fast procedure and time to ambulation. The rate of periprocedural complications was low.

Novel or established cryoballoon ablation system for pulmonary vein isolation: the prospective ICE-AGE-1 study.

AIMS: Catheter ablation with a cryoballoon (CB) provides effective and durable pulmonary vein (PV) isolation (PVI) associated with encouraging clinical outcome data. The novel POLARx CB incorporates unique features, which may translate into improved safety, efficacy, and outcomes. The ICE-AGE-1 study aimed to assess the efficacy, safety, and 1-year clinical follow-up of the POLARx CB in comparison to the Arctic Front Advance Pro CB (AF-CB4). METHODS AND RESULTS: A total of 103 consecutive patients with paroxysmal or persistent atrial fibrillation (AF) who underwent POLARx-based PVI (POLARx group) were prospectively enrolled and were compared to 102 consecutive patients previously treated with the AF-CB4 (AF-CB4 group). The mean age was 68.7 ± 10.2 (POLARx) and 65.7 ± 12 (AF-CB4, P = 0.0551) years. A total of 412 (POLARx) and 404 (AF-CB4) PVs were identified. All PVs, except for one PV in the POLARx group, were successfully isolated. A significant difference regarding the mean minimal CB temperature reached using the POLARx CB (-56.1 ± 8.3°C) and AF-CB4 (-46.9 ± 10.1°C) was observed (P < 0.0001). Real-time PVI was visualized in 71% of PVs in the POLARx group and 46% of them in the AF-CB4 group (P < 0.001). The mean procedure time was comparable: 54.5 ± 17.1 min for POLARx and 59.4 ± 18.6 min for AF-CB4 (P = 0.0509). No differences were observed in terms of periprocedural complications. There were comparable rates in freedom of AF or atrial tachycardia recurrence after 12 months, beyond a 90-day long blanking period: 78.9% in the POLARx group vs. 77.2% in the AF-CB4 group (P = 0.804). CONCLUSION: The novel POLARx CB showed similar safety, efficacy, and 1-year recurrence-free survival rates compared to the AF-CB4. A higher rate of real-time electrical PV recordings and significantly lower balloon temperatures were observed using the POLARx as compared to AF-CB4.

Wide antral circumferential vs. ostial pulmonary vein isolation using pulsed field ablation-the butterfly effect.

Background: Wide antral circumferential ablation (WACA) in comparison to ostial pulmonary vein (PV) isolation (PVI) has been attributed with improved rhythm outcome. We investigated the feasibility, lesion formation, and rhythm outcome of WACA-PVI in comparison to ostial-PVI using pulsed field ablation (PFA). Methods: Symptomatic atrial fibrillation (AF) patients (69 years, 67% male; 67% paroxysmal AF) were prospectively enrolled into our single-center registry and underwent first-time ostial-PFA or WACA-PFA, N = 15 each. In all patients, eight pulse trains (2 kV/2.5 s, bipolar, biphasic, 4× basket/flower configuration each) were delivered to each PV. In WACA-PFA, two extra pulse trains in a flower configuration were added to the anterior and posterior antrum of the PVs. For comparison of PFA lesion size, pre- and post-ablation left atrial (LA) voltage maps were acquired using a multipolar spiral catheter together with a three-dimensional electroanatomic mapping system. Results: WACA-PFA resulted in a significant larger lesion formation than ostial-PFA (45.5 vs. 35.1 cm2, p = 0.001) with bilateral overlapping butterfly shape-like lesions and concomitant posterior LA wall isolation in 73% of patients. This was not associated with increased procedure time, sedation dosage, or exposure to radiation. One-year freedom from AF recurrence was numerically higher after WACA-PFA than ostial-PFA (94% vs. 87%) but not statistically significant (p = 0.68). No organized atrial tachycardias (ATs) were observed. Ostial-PFA patients more often underwent re-ablation due to recurrent AF episodes. Conclusion: WACA-PFA is feasible and resulted in significantly wider lesion sets than ostial-PFA. Concomitant posterior LA wall isolation occurred as an epiphenomenon in the majority of patients. The WACA approach was associated with neither increased procedure and fluoroscopy times nor statistically significant differences in 1-year rhythm outcome. ATs were absent.

Left atrial appendage closure in end-stage renal disease and hemodialysis: Data from a German multicenter registry.

BACKGROUND: Left atrial appendage closure (LAAC) has emerged as an alternative to oral anticoagulation (OAC) for stroke prevention in patients with atrial fibrillation (AF). OAC treatment has been proven feasible in mild-to-moderate chronic kidney disease (CKD). In contrast, the optimal antithrombotic management of AF patients with end-stage renal disease (ESRD) is unknown and LAAC has not been proven in these patients in prospective randomized clinical trials. OBJECTIVES: The objective of this study is to evaluate safety and efficacy of LAAC in patients with ESRD. METHODS: Patients undergoing LAAC were collected in a German multicenter real-world observational registry. A composite endpoint consisting of the occurrence of ischemic stroke/transient ischemic attack, systemic embolism, and/or major clinical bleeding was assessed. Patients with ESRD were compared with propensity score-matched patients without severe CKD. ESRD was defined as a glomerular filtration rate < 15 ml/min/1.73 m2 or chronic hemodialysis treatment. RESULTS: A total of 604 patients were analyzed, including 57 with ESRD and 57 propensity-matched patients. Overall, 596 endocardial and 8 epicardial LAAC procedures were performed. Frequency of major complications was 7.0% (42/604 patients) in the overall cohort, 8.8% (5/57 patients) in patients with ESRD, and 10.5% (6/57 patients) in matched controls (p = 0.75). The estimated event-free survival of the combined endpoint after 500 days was 90.7 ± 4.5% in patients with ESRD and 90.2 ± 5.5% in matched controls (p = 0.33). CONCLUSIONS: LAAC had comparable procedural safety and clinical efficacy in patients with ESRD and patients without severe CKD.

Very high-power short-duration ablation for pulmonary vein isolation utilizing a very-close protocol-the FAST AND FURIOUS PVI study.

AIMS: The very high-power short-duration (vHP-SD) radiofrequency (RF) ablation concept of atrial fibrillation (AF) treatment by pulmonary vein isolation (PVI) aims for safer, more effective, and faster procedures. Utilizing conventional ablation, the 'close protocol' has been verified. Since lesion formation of vHP-SD ablation creates wider but shallower lesions we adapted the close protocol to an individualized and tighter 'very-close protocol' of 3-4 mm of inter-lesion distance (ILD) at the anterior and 5-6 mm at the posterior aspect of the left atrium using vHP-SD only. Here, we evaluated the safety and efficacy of vHP-SD ablation for PVI utilizing a very-close protocol in comparison with standard ablation. METHODS AND RESULTS: A total of 50 consecutive patients with symptomatic AF were treated with a very-close protocol utilizing vHP-SD (vHP-SD group). The data were compared with 50 consecutive patients treated by the ablation-index-guided strategy (control group). The mean RF time was 352 ± 81 s (vHP-SD) and 1657 ± 570 s (control, P < 0.0001), and the mean procedure duration was 59 ± 13 (vHP-SD) and 101 ± 38 (control, P < 0.0001). The first-pass isolation rate was 74% (vHP-SD) and 76% (control, P = 0.817). Severe adverse events were reported in 1 (2%, vHP-SD) and 3 (6%, control) patients (P = 0.307). A 12-month recurrence-free survival was 78% (vHP-SD) and 64% (control, P = 0.142). PVI durability assessed during redo-procedures was 75% (vHP-SD) vs. 33% (control, P < 0.001). CONCLUSIONS: PVI solely utilizing vHP-SD via a very-close protocol provides safe and effective procedures with a high rate of first-pass isolations. The procedure duration and ablation time were remarkably low. A 12-month follow-up and PVI durability are promising.

Antithrombotic therapy after angioplasty of pulmonary vein stenosis due to atrial fibrillation ablation: A two-center experience and review of the literature.

Background: Pulmonary vein stenosis (PVS) is a severe complication of atrial fibrillation (AF) ablation resulting in narrowing of affected pulmonary veins (PVs). Interventional treatment consists of angioplasty with or without PV stenting. The optimal postprocedural antithrombotic therapy is not known. Study aims: To investigate the impact of antithrombotic medical therapy on recurrence of PVS after PV angioplasty. Methods: A retrospective study of patients undergoing PV angioplasty with or without stent implantation in two German centers was performed. Postinterventional antithrombotic therapy consisted of either dual antiplatelet therapy (DAPT) or a combination of oral anticoagulation with single or dual antiplatelet therapy for 3-12 months after intervention. Angiographic follow-up was recommended 3, 6, and 12 months after intervention and in case of symptom recurrence. Results: Thirty patients underwent treatment of 42 PVS. After intervention, twenty-eight patients received triple therapy and 14 patients received dual therapy/DAPT; restenosis occurred in 5/22 (22.7%) patients with triple therapy and 8/14 (57.1%) patients with dual therapy/DAPT PV (p = .001). Estimated freedom from PV restenosis after 500 days was 18.8 ± 15.8% (dual therapy/DAPT) and 76.2 ± 10.5% (triple therapy) (p = .003). Univariate regression analysis revealed postprocedural medication as a significant risk factor for restenosis (p = .019). No bleeding events occurred regardless of applied antithrombotic therapy. Conclusion: Triple antithrombotic therapy after PV angioplasty is associated with less frequent restenosis as compared to dual antiplatelet therapy or a combination of anticoagulation and single antiplatelet therapy. No severe bleeding events occurred in patients on triple therapy. These findings need to be confirmed in larger patient cohorts.

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

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

Repeat catheter ablation in patients with atrial arrhythmia recurrence despite durable pulmonary vein isolation.

INTRODUCTION: Arrhythmia recurrence after pulmonary vein isolation (PVI) in patients with atrial fibrillation (AF) is common and often linked to pulmonary vein reconnection. In patients with arrhythmia recurrences despite durable PVI the optimal ablation approach is unclear. The purpose of the present study was to analyze efficacy of extended ablation maneuvers in these patients and predictors of procedural success. METHODS: Consecutive patients with durable PVI undergoing repeat ablation procedures were prospectively enrolled. Patients underwent substrate modification with creation of linear lesions and/or mechanism-specific atrial tachycardia (AT) ablation. Three dimensional-mapping images were analyzed for the presence of left atrial (LA) low-voltage areas according to published scoring systems. RESULTS: Seventy-four patients were analyzed. Mode of recurrence after durable PVI was AF in 27 patients (36.5%) and AT in 47 patients (63.5%). Linear lesion ablation was performed in 60 patients (81.1%). Twenty-four patients (32.4%) were treated for focal AT mechanisms. Mean follow-up was 565 ± 342 days. Estimated arrhythmia-free survival after 24 months was significantly higher in patients with AT than in patients with AF as mode of recurrence after durable PVI (42.9 ± 8.2% vs. 24.7 ± 8.5%, p = .023) and in patients without compared to patients with marked LA low-voltage areas (40.5 ± 9.2% vs. 22.8 ± 8.5%, p = .041). The mode of recurrence after durable PVI was the only independent predictor of further arrhythmia recurrence after repeat ablation. CONCLUSION: Arrhythmia-free survival following repeat ablation procedures in patients with durable PVI highly depends on mode of arrhythmia recurrence and the presence of LA low-voltage areas.

Stand-alone Focal Impulse and Rotor Modulation (FIRM) ablation versus second-generation cryoballoon pulmonary vein isolation for paroxysmal atrial fibrillation.

INTRODUCTION: Focal Impulse and Rotor Modulation (FIRM) guided catheter ablation aiming at stable rotors has been investigated as a treatment option in patients with atrial fibrillation (AF). The objective of this study was to compare the safety and efficacy of FIRM-guided ablation with second-generation cryoballoon pulmonary vein isolation (CB2-PVI) in paroxysmal AF. METHODS: Consecutive patients (n = 22, mean age 60 ± 11 years, 59.1% of males) who were treated with a stand-alone FIRM-guided ablation were included in this retrospective single-center study. Procedural data and arrhythmia-free survival at 12 months were compared with n = 86 consecutive patients (mean age 62 ± 13 years, 62.4% of males) who received de-novo CB2-PVI. RESULTS: Median procedure duration was significantly longer in the FIRM group than in the CB2-PVI group (152 [IQR 120-176] minutes vs. 122 [110-145] minutes; p = .031). One patient (1.2%) in the CB2-PVI group and five patients (22.7%) in the FIRM group had vascular access complications. Atrial tachyarrhythmias recurred in 15 patients in the FIRM group and 11 in the CB2-PVI group. Kaplan-Meier estimation of single-procedure arrhythmia-free survival at 12 months was 25% (95% confidence interval [CI] 6%-44%) in the FIRM group and 87% (95% CI 78%-96%) in the CB2-PVI group (p < .001). Repeat ablations were performed in 14/20 (70.0%) patients in the FIRM group and in 12/85 (14.1%) in the CB2-PVI group (p < .001). CONCLUSION: De novo ablation of AF using FIRM-guided AF ablation results in shorter arrhythmia-free survival after 12 months compared to CB2-PVI and a need for repeat ablation in the majority of patients to achieve stable sinus rhythm.

Very-high-power short-duration ablation for treatment of premature ventricular contractions - The FAST-AND-FURIOUS PVC study.

Objectives: We sought to assess the efficacy, safety and short-term clinical outcome of very high-power short-duration (vHP-SD) radiofrequency (RF) catheter ablation for the treatment of idiopathic PVCs originating from the cardiac outflow tract (OT). Background: Power-controlled RF ablation is a widely used technique for the treatment of premature ventricular contractions (PVCs). A novel ablation catheter offers three microelectrodes and six thermocouples at its tip and provides temperature-controlled vHP-SD (90 Watts/4 s,) with the opportunity to switch to moderate-power mode. Methods: In this pilot study, twenty-four consecutive, prospectively enrolled patients underwent PVC ablation utilizing the vHP-SD ablation (study group) and were compared with 24 consecutive patients previously treated with power-controlled ablation (control group). Each group included 12 patients with PVCs originating from the right ventricular OT (RVOT) and 12 patients with PVCs originating from the left ventricular OT (LVOT). The acute endpoint was PVC elimination and was achieved in all patients. Results: In 16/24 (67%) patients (study group) it was achieved by using vHP-SD only. The median RF delivery time was 52 (interquartile range [IQR] 16, 156) seconds (study group) and 350 (IQR 240, 442) seconds (control group, p < 0.0001). No difference was observed regarding procedure duration (p = 0.489) as well as 6-months follow-up (p = 0.712). One (4%, study group) and 2 (8%, control group) severe adverse events occured (p = 0.551). Conclusion: In this study, vHP-SD PVC ablation was similarly effective and safe as compared to conventional power-controlled ablation. The RF time was significantly shorter.

Catheter Ablation for Atrial Fibrillation in Patients ≤30 Years of Age.

Pulmonary vein (PV) automaticity is an established trigger for paroxysmal atrial fibrillation (PAF), making PV isolation (PVI) the cornerstone of catheter ablation. However, data on triggers for atrial fibrillation (AF) and catheter ablation strategy in very young patients aged <30 years are sparse. A total of 51 young patients (mean age 24.0 ± 4.2 years, 78.4% men) with drug-refractory PAF underwent electrophysiology (EP) study and ablation at 5 EP centers. None of the patients had structural heart disease or family history of AF. EP study induced supraventricular tachycardia (SVT) in 12 patients (n = 12, 23.5%): concealed accessory pathway mediated orthodromic atrioventricular reentrant tachycardia in 3 patients, typical atrioventricular nodal reentrant tachycardia in 6 patients, left superior PV tachycardia in 1 patient, left atrial appendage tachycardia in 1 patient, and typical atrial flutter in 1 patient. In patients with induced SVTs, SVT ablation without PVI was performed as an index procedure, except for the patient with atrial flutter who received cavotricuspid isthmus ablation in addition to PVI. Remaining patients underwent radiofrequency (n = 15, 29.4%) or second-generation cryoballoon-based PVI (n = 24, 47%). There were no major complications related to ablation procedures. Follow-up was based on outpatient visits including 24-hour Holter-electrocardiogram at 3, 6, and 12 months after ablation, or additional Holter-electrocardiogram was ordered in case of symptoms suggesting recurrence. Recurrence was defined as any atrial tachyarrhythmia (ATA) episode >30 seconds after a 3-month blanking period. A total of 2 patients with atrioventricular nodal reentrant tachycardia, 1 with left atrial appendage tachycardia, experienced AF recurrence within the first 3 months and received PVI. After the 3-month blanking period, during a median follow-up of 17.0 ± 10.1 months, 44 of 51 patients (86.2%) were free of ATA recurrence. In the PVI group, 33 of 39 patients (84.6%) experienced no ATA recurrence. In conclusion, SVT substrate is identified in around a quarter of young adult patients with history of AF, and targeted ablation without PVI may be sufficient in the majority of these patients. PVI is needed in the majority and is safe and effective in this population.

Catheter ablation of supraventricular tachycardia in patients with and without structural heart disease: insights from the German ablation registry.

AIM: To compare patient characteristics, safety and efficacy of catheter ablation of supraventricular tachycardia (SVT) in patients with and without structural heart disease (SHD) enrolled in the German ablation registry. METHODS AND RESULTS: From January 2007 until January 2010, a total of 12,536 patients (37.2% with known SHD) were enrolled and followed for at least one year. Patients with SHD more often underwent ablation for atrial flutter (45.8% vs. 20.9%, p < 0.001), whereas patients without SHD more often underwent ablation for atrioventricular nodal reentrant tachycardia (30.2% vs. 11.8%, p < 0.001) or atrioventricular reentrant tachycardia (9.1% vs. 1.6%, p < 0.001). Atrial fibrillation catheter ablation procedures were performed in a similar proportion of patients with and without SHD (38.1% vs. 36.9%, p = 0.21). Overall, periprocedural success rate was high in both groups. Death, myocardial infarction or stroke occurred in 0.2% and 0.1% of patients with and without SHD (p = 0.066). Major non-fatal complications prior to discharge were rare and did not differ significantly between patients with and without SHD (0.5% vs. 0.4%, p = 0.34). Kaplan-Meier mortality estimate at 1 year demonstrated a significant mortality increase in patients with SHD (2.6% versus 0.7%; p < 0.001). CONCLUSION: Patients with and without SHD undergoing SVT ablation exhibit similar success rates and low major complication rates, despite disadvantageous baseline characteristics in SHD patients. These data highlight the safety and efficacy of SVT ablation in patients with and without SHD. Nevertheless Kaplan-Meier mortality estimates at 1 year demonstrate a significant mortality increase in patients with SHD, highlighting the importance of treating the underlying condition and reliable anticoagulation if indicated.