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Aims Catheter ablation (CA) is recommended for patients with atrial fibrillation (AF) after failure of antiarrhythmic drugs (AADs). The role of CA as ‘initial therapy’ for AF is to be determined. Methods and results Following PRISMA guideline an up-to-date pooled analysis of randomized data comparing ablation vs. AADs as first-line therapy for symptomatic AF was performed. The primary outcome was recurrence of atrial tachyarrhythmia. The secondary outcomes were improvement in quality-of-life (QoL) and major adverse events. A total of 997 patients from five randomized trials were enrolled (mean age 57.4 years, 68.6% male patients, 98% paroxysmal AF, mean follow-up 1.4 years). The baseline characteristics were similar between the ablation and AADs group. Overall pooled analysis showed that, as compared with AADs, CA as first-line therapy was associated with significantly higher freedom from arrhythmia recurrence (69% vs. 48%, odds ratio: 0.36, 95% confidence interval: 0.27–0.48, P Conclusions Catheter ablation as ‘initial therapy’ was superior to AADs in maintenance of sinus rhythm and improving QoL for patients with symptomatic paroxysmal AF, without increasing risk of serious adverse events.

Aims Anticoagulation for atrial fibrillation patients with liver disease represents a clinical dilemma. We sought to evaluate the efficacy/safety of different anticoagulation, i.e. vitamin K antagonist (VKA) and non-VKA oral anticoagulants (NOACs) in such patient group. Methods and results This was a pooled-analysis enrolling up-to-date clinical data. Two subsets: subset A (VKA vs. Non-Anticoagulation) and subset B (NOACs vs. VKA) were pre-specified. The study outcomes were ischaemic stroke (IS)/thromboembolism (TE), major bleeding (MB), intracranial bleeding (ICB), gastrointestinal bleeding (GIB), and all-cause mortality. A total of 20 042 patients’ data were analysed (subset A: N = 10 275, subset B: N = 9767). Overall mean age: 71 ± 11 years, mean CHA2DS2-VASc score: 4.0 ± 1.8, mean HAS-BLED score: 3.6 ± 1.2. The majority of the patients had Child-Pugh category (A-B). As compared with Non-Anticoagulation, VKA seemed to reduce the risk of IS/TE [odds ratio (OR): 0.60, P = 0.05], but heighten the risk of all-bleeding events including MB (OR: 2.81, P = 0.01), ICB (OR: 1.60, P = 0.01), and GIB (OR: 3.32, P = 0.01). When compared with VKA, NOACs had similar efficacy in reducing the risk of IS/TE (OR: 0.82, P = 0.64), significantly lower risk of MB (OR: 0.54, P = 0.0003) and ICB (OR: 0.35, P Conclusions VKA appears to reduce the risk of IS/TE but increase all-bleeding events. NOACs have similar effect in reducing the risk of IS/TE and have significantly lower risk of MB and ICB as compared with VKA. NOACs seem to be associated with better clinical outcome than VKA in patients with mild–moderate liver disease.

Maze‐like linear substrate modification in atrial fibrillation patients nonresponders to pulmonary vein isolation represents a feasible technique to gain left atrial appendage electrical isolation even in the presence of a Watchman occluder device.

Supplemental Digital Content is available in the text., Background: Cryoballoon-based pulmonary vein isolation (PVI) has emerged as an effective treatment for atrial fibrillation. The most frequent complication during cryoballoon-based PVI is phrenic nerve injury (PNI). However, data on PNI are scarce. Methods: The YETI registry is a retrospective, multicenter, and multinational registry evaluating the incidence, characteristics, prognostic factors for PNI recovery and follow-up data of patients with PNI during cryoballoon-based PVI. Experienced electrophysiological centers were invited to participate. All patients with PNI during CB2 or third (CB3) and fourth-generation cryoballoon (CB4)-based PVI were eligible. Results: A total of 17 356 patients underwent cryoballoon-based PVI in 33 centers from 10 countries. A total of 731 (4.2%) patients experienced PNI. The mean time to PNI was 127.7±50.4 seconds, and the mean temperature at the time of PNI was −49±8°C. At the end of the procedure, PNI recovered in 394/731 patients (53.9%). Recovery of PNI at 12 months of follow-up was found in 97.0% of patients (682/703, with 28 patients lost to follow-up). A total of 16/703 (2.3%) reported symptomatic PNI. Only 0.06% of the overall population showed symptomatic and permanent PNI. Prognostic factors improving PNI recovery are immediate stop at PNI by double-stop technique and utilization of a bonus-freeze protocol. Age, cryoballoon temperature at PNI, and compound motor action potential amplitude loss >30% were identified as factors decreasing PNI recovery. Based on these parameters, a score was calculated. The YETI score has a numerical value that will directly represent the probability of a specific patient of recovering from PNI within 12 months. Conclusions: The incidence of PNI during cryoballoon-based PVI was 4.2%. Overall 97% of PNI recovered within 12 months. Symptomatic and permanent PNI is exceedingly rare in patients after cryoballoon-based PVI. The YETI score estimates the prognosis after iatrogenic cryoballoon-derived PNI. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03645577. Graphic Abstract: A graphic abstract is available for this article.

Background The left atrial appendage (LAA) has been identified as a potential source of atrial fibrillation (AF) and has been described as the "fifth" pulmonary vein (PV). We report our initial experience in LAA isolation (LAAI) using the cryoballoon (CB) and data on durability of CB-LAAI. Methods Patients treated with a CB-LAAI were retrospectively identified. Six weeks after electrical LAAI, patients were scheduled for staged percutaneous LAA closure. During the second procedure, a subset of patients underwent invasive remapping of the LAA. Results A total of 32 patients (21 males, 68 ± 10 years old) were treated with CB-LAAI. Acute LAAI was achieved in 29 of 32 (91%) patients: single-shot LAAI was observed in 18 of 32 (56%) patients. Acute procedural sustained LAAI was related with a significantly shorter time to LAAI (sustained LAAI: 84 ± 50 s vs nonsustained LAAI: 166 ± 76 s, P = 0.004). Mean procedure and fluoroscopy time were 61 ± 29 and 8 ± 6 min, respectively. One left-sided phrenic nerve palsy occurred. In 25 of 32 (78%) patients, a second procedure for percutaneous LAA closure device implantation was performed. In 22 patients, persistency of LAAI was tested: durable LAAI was documented in 16/22 patients (73%). Conclusion In the present report, CB LAA isolation followed by staged LAA closure appeared to be safe and feasible but more data are required. Time to LAAI played a role in predicting acute sustained LAAI rate. CB LAA ablation leads to 73% of durable LAA isolation.

Introduction Stroke is one of the most feared complications during catheter ablation of atrial fibrillation (AF). While symptomatic thromboembolic events are rare, magnetic resonance imaging (MRI) may identify asymptomatic (ie, silent) cerebral lesions (SCLs) following pulmonary vein isolation (PVI) procedures. Methods and Results The REDUCE‐TE Pilot was a prospective multicenter, single‐arm observational study investigating the incidence of SCL in patients with symptomatic paroxysmal AF undergoing PVI with a novel gold‐tip, externally irrigated ablation catheter. After ablation, cerebral diffusion‐weighted MRI and a postablation follow‐up were performed at 1 to 3 days after the ablation procedure. A neurocognitive test was done before and after ablation. The primary study endpoint was the occurrence of one or more new SCLs. Secondary study endpoints included neurocognitive status, procedural success rate, and periprocedural complications including symptomatic thromboembolic events. A total of 104 patients were enrolled (69% male, mean age: 61.5 ± 9.7 years, mean CHA2DS 2‐VASc score: 1.7 ± 1.2). Postprocedural MRI examination was performed in 97 patients, and in nine of them (9.3%; 95% CI: 4.3‐16.9%) a total of 11 SCLs were detected. Univariate analyses did not reveal any significant predictor for new SCLs. Nonsignificant trends were observed for low activated clotting time during ablation and for international normalized ratio value outside the range of 2 to 3 at ablation. There was no evidence of significant deterioration of neurocognitive function after PVI. In four patients, a pericardial tamponade was noted but all patients fully recovered during follow‐up. Conclusions Ablation of AF using a novel gold‐tip, externally irrigated ablation catheter, resulted in SCLs in approximately one out of 10 patients without a measurable effect on neurocognitive function.

Background: Pulmonary vein isolation (PVI) represents the cornerstone in atrial fibrillation ablation. Cryoballoon and laserballoon catheters have emerged as promising devices but lack randomized comparisons. Therefore, we sought to compare efficacy and safety comparing both balloons in patients with persistent and paroxysmal atrial fibrillation (AF). Methods: Symptomatic AF patients (n=200) were prospectively randomized (1:1) to receive either cryoballoon or laserballoon PVI (cryoballoon: n=100: 50 paroxysmal atrial fibrillation + 50 persistent AF versus laserballoon: n=100: 50 paroxysmal atrial fibrillation + 50 persistent AF). All antiarrhythmic drugs were stopped after ablation. Follow-up included 3-day Holter-ECG recordings and office visits at 3, 6, and 12 months. Primary efficacy end point was defined as freedom from atrial tachyarrhythmia between 90 and 365 days after a single ablation. Secondary end points included procedural parameters and periprocedural complications. Results: Patient baseline parameters were not different between both groups. In all (n=200) complete PVI was obtained and the entire follow-up accomplished. Balloon only PVI was obtained in 98% (cryoballoon) versus 95% (laserballoon) requiring focal touch-up in 2 and 5 patients, respectively. Procedure but not fluoroscopy time was significantly shorter in the cryoballoon group (50.9±21.0 versus 96.0±20.4 minutes; P P =0.083). Overall, the primary end point of no atrial tachyarrhythmia recurrence was met in 79% (cryoballoon: 80.0% versus laserballoon: 78.0%, P =ns). No death, atrio-esophageal fistula, tamponade, or vascular laceration requiring surgery occurred. In the cryoballoon group, 8 transient but no persistent phrenic nerve palsy were noted compared with 2 persistent phrenic nerve palsy and one transient ischemic attack in the laserballoon group. Conclusions: Both balloon technologies represent highly effective and safe tools for PVI resulting in similar favorable rhythm outcome after 12 months. Use of the cryoballoon is associated with significantly shorter procedure but not fluoroscopy time.

Aims Cryoballoon (CB) pulmonary vein isolation (PVI) is an accepted ablation strategy for rhythm control in atrial fibrillation (AF). We describe efficacy and safety in a high volume centre with a long experience in the use of the second-generation CB (CB2). Methods and results Consecutive paroxysmal AF (PAF) or persistent AF (persAF) patients undergoing CB2-PVI were enrolled. Procedural data, efficacy, and safety issues were systematically collected. The 28 mm CB2 was used in combination with an inner lumen spiral catheter, a luminal oesophageal temperature (LET) probe was used with a cut-off of 15°C, the phrenic nerve (PN) monitored during septal PVs ablation. Freeze duration was mainly set at 240 s with a bonus application in case of delayed time-to-isolation (TTI > 75 s). A total of 1017 CB2 procedures were analysed (58% male, 66 ± 12 years old, 70% with PAF). 3964 PVs were identified, 99.8% PVs isolated using solely the 28 mm CB. Mean procedure time was 69 ± 25 min, TTI during the first application was recorded in 77% of PVs after a mean of 48 ± 31 s. We recorded 0.2% cardiac tamponade, 4.8% PN injury (1.6% of PN palsy), and 19% of LET Conclusion Cryoballoon procedures are fast and associated with a benign safety profile. Shorter TTI and longer freeze durations are associated with sinus rhythm during follow-up.

BACKGROUND It remains unclear whether left atrial low-voltage area (LALVA) affects atrial tachyarrhythmia recurrence after laser balloon pulmonary vein isolation (PVI) for atrial fibrillation (AF). We prospectively evaluated the outcome of laser balloon PVI in patients with and without LALVA (≤ 0.5 mV) together with surface/intracardiac electrophysiological criteria. METHODS One hundred consecutive paroxysmal/persistent AF patients underwent laser balloon PVI. The relative extent of LALVA (extent of LALVA/left atrial surface area × 100 [%]: rLALVA), total p-wave duration in lead II (PWD), and time interval from the beginning of p-wave to the local activation in left atrial appendage (TTLAA) were assessed. Patients were divided into patients with LALVA (group A: 23 patients) and those without LALVA (group B: 77 patients). The primary endpoint was freedom from atrial tachyarrhythmia after the blanking periods. RESULTS Complete PVI was achieved in 99/100 (99%) patients. PWD and TTLAA were longer in group A (both, P

BACKGROUND The incidence of pulmonary vein stenosis (PVS) after AF ablation following contemporary procedures remains unclear. We compared the incidence of PVS/narrowing (PVS/N) after PV isolation (PVI) for (1) 3-D mapping-guided wide-area encircling irrigated radiofrequency current (RFC) ablation; (2) first-third-generation big cryoballoon (CB1-3) ablation; and (3) laser balloon (LB) ablation.Methods and Results:All patients undergoing a second procedure between January 2012 and November 2016 were subgrouped according to index ablation (PVI): RFC; CB; or LB. PVS/N was classified using PV diameter ratio (second/index procedure) on selective PV angiogram performed before ablation: mild, 25-49%; moderate, 50-74%; or severe, ≥75%. A total of 344 patients (1,362 PV) were analyzed (RFC, n=211; 840 PV; CB1, n=21; 82 PV; CB2,3, n=64; 250 PV; LB, n=48; 190 PV). In the LB group, 45 patients (94%) were treated with dose ≥8.5 W. Second procedures were performed on average 14.9±14.1 months after the index procedure. Mild PVS/N was observed in 18.4%, 9.5% and 3.6% of PV in the LB, RFC and CB groups, respectively (P

Aims The long-term outcomes of left atrial appendage electrical isolation (LAAEI) in patients with non-paroxysmal atrial fibrillation (AF) have corroborated the significant role of the LAA in this arrhythmia. We sought to investigate the incremental benefit of LAAEI in patients undergoing catheter ablation for persistent AF or long-standing persistent AF (LSPAF). Methods and results A systematic review of Medline, Cochrane, and Embase for all the clinical studies in which assessment LAAEI in non-paroxysmal AF patients was performed. The benefit of LAAEI in patients with AF was analysed from seven studies that enrolled a total of 930 patients [mean age 63 ± 5 years; male: 69%]. All studies included patients with either persistent AF or LSPAF or the combination of them. The overall freedom from all-arrhythmia recurrence at 12 months of follow-up off antiarrhythmic medications in patients who underwent LAAEI was 75.5% vs. 43.9% in those in whom only standard ablation was performed [56% relative reduction and 31.6% absolute reduction; risk ratio (RR) 0.44, 95% confidence interval (95% CI) 0.31-0.64; P

Background An increased incidence of esophageal lesions (EL) after pulmonary vein isolation (PVI) using the second-generation cryoballoon (CB2) has been described. We hypothesized that luminal esophageal temperature (LET)–guided PVI reduces the incidence of EL. Objective The aim of this study was to investigate the incidence of EL after LET-guided PVI using the CB2. Methods Ninety-four consecutive patients underwent CB2-PVI for paroxysmal or persistent atrial fibrillation. Target freezing time was 2 × 240 seconds. LET was continuously measured by a probe with 3 thermocouples. Early freezing interruption was performed when LET reached a prespecified cutoff temperature. A group of 32 patients who underwent CB2-PVI with observational LET measurement served as the control group. Postprocedural esophagoscopy was performed in all patients. Results Compared with observational LET measurement, a strategy of LET-guided CB-PVI significantly reduced the incidence of EL from 18.8% to 3.2% ( P = .008). A progressive decline in the incidence of EL was observed with an increasing LET cutoff: 7.1% (2/28 patients, 12°C cutoff) and 1.5% (1/66 patients, 15°C cutoff, P = .005 vs control). Despite early freezing interruption at a single pulmonary vein in 27% (25/94) of patients, complete PVI was achieved in all patients using the 28 mm balloon. Repeat esophagoscopy confirmed healing of EL after 1 week. After a mean of 268 ± 119 days, 87% (76/87) of patients were free of recurrent atrial fibrillation or atrial tachycardia following a 90-days blanking period. Conclusion LET-guided CB2-PVI significantly reduced the incidence of thermal EL. Interrupting cryoablation at 15 ° C LET was associated with the lowest incidence of esophageal injury.

Aims The second-generation cryoballoon (CB2) with increased surface cooling has recently become available. The aim was to investigate the incidence and characteristics of phrenic nerve palsy (PNP) during pulmonary vein isolation (PVI) using the CB2 as compared with the first-generation balloon (CB1). Methods and results A total of 360 consecutive patients with atrial fibrillation underwent PVI with the CB1 (106 patients) or the CB2 (254 patients). Right PN function was monitored by continuous stimulation and palpation during septal PV ablation. Persistent PNP (present at discharge) occurred in 2.8 and 1.9% ( P = 0.63) of patients, transient PNP (full recovery before discharge) in 5.9 and 3.8% ( P = 0.41) of patients in the CB2 and CB1 group, respectively. Phrenic nerve palsy during ablation at the right inferior PV was observed in 0% (CB1) and 4.3% (CB2, P = 0.03) of patients. Using the CB2, a trend of reduced incidence of persistent PNP over quartiles of consecutive patients was observed [4.8% (Q1) vs. 0% (Q4); P = 0.077]. At the culprit PV, PNP occurred after 3.5 ± 2.1 (CB1) and 1.1 ± 0.4 applications (CB2; P = 0.036). Complete recovery of PN function occurred after 29 ± 11 (CB1) and 259 ± 137 days (CB2; P = 0.004). Conclusions The rate of transient/persistent PNP associated with the use of the CB2 was 5.9 and 2.8%, respectively. Time to restitution of PN function was longer using the CB2.

Background The novel second-generation cryoballoon (CB) facilitates pulmonary vein isolation (PVI) by improved surface cooling. The impact of this redesign on collateral damage is unknown. Objective To investigate the incidence of esophageal lesions after PVI using the second-generation CB and the role of luminal esophageal temperature (LET) measurement as a predictor of lesion formation. Methods Thirty-two consecutive patients underwent PVI using the second-generation 28 mm CB. Target application time was 2×240 seconds. Ninety-two percent of the PVs were isolated after 1 cryoenergy application. Complete PVI was achieved in all patients. LET with 3 thermocouples was continuously measured during cryoenergy application. Freezing was interrupted only if weakening/loss of phrenic nerve function or low LET ( Results The lowest measured LET was−12°C (despite cryoapplication interruption). Postprocedural gastroesophagoscopy was performed after 1–3 days in all patients and showed lesions in 6 of 32 (19%) patients. A minimum LET of≤12°C predicted esophageal lesions with 100% sensitivity and 92% specificity (area under the receiver-operator characteristic curve 0.97; 95% CI 0.93–1.02; P = .001). Persistent phrenic nerve palsy occurred in 2 (6%) patients during ablation at the right inferior pulmonary vein. Repeat gastroesophagoscopy confirmed healing of lesions after 16±14 days. Conclusions Second-generation 28 mm CB PVI is associated with significant esophageal cooling, resulting in lesion formation in 19% of the patients. LET measurement accurately predicts lesion formation and may enhance the safety of the novel device.

In a 66-year-old male (CHA2DS2-VASc score=3) referred for catheter ablation of persistent atrial fibrillation, transesophageal echocardiography revealed a large left atrial appendage (LAA) thrombus (Figure A; Movie I in the Data Supplement), despite continuous treatment with rivaroxaban 20 mg daily. Figure. A , Two-dimensional transesophageal echocardiography (TEE) image showing thrombus inside left atrial appendage (LAA; diameter 9×19 mm). B , LAA landing zone in 2-dimensional TEE. …

Introduction: We report on a 63-year-old female patient in whom an electrophysiologic study discovered a hemi-azygos continuation. Using the magnetic navigation system, remote-controlled ablation was performed in conjunction with the 3D electroanatomical mapping system. Methods and Results: Failing the attempt to advance a diagnostic catheter from the femoral vein, a diagnostic catheter was advanced via the left subclavian vein into the coronary sinus. The soft magnetic catheter was positioned in the right atrium via the hemi-azygos vein, and 3D mapping demonstrated an ectopic atrial tachycardia. Successful ablation was performed entirely remote controlled. Fluoroscopy time was only 7.1 minutes, of which 45 seconds were required during remote navigation. Conclusion: Remote-controlled catheter ablation using magnetic navigation in conjunction with the electroanatomical mapping system proved to be a valuable tool to perform successful ablation in the presence of a hemi-azygos continuation.

Introduction: The magnetic navigation system (MNS) allows remote-controlled navigation of an ablation catheter from the control room. We tested the hypothesis, whether the MNS and a single additional diagnostic nonsteerable catheter would have the potential to identify the tachycardia substrate and allow subsequent ablation in patients with documented supraventricular tachycardia (SVT). Methods and Results: A total of 41 patients (24 females, age 45 ± 16 years) underwent an invasive electrophysiologic (EP) study using the MNS. Together with a conventional diagnostic catheter in the right ventricle, the magnetic catheter (MC) was used to investigate the underlying EP substrate in a sequential fashion and subsequently to perform radiofrequency (RF) ablation. A custom-made device allowed the separate assessment of fluoroscopy deployed from the control and examination room. Using conventional EP criteria, identification of the underlying substrate was possible in all but 4 noninducible patients (no accessory pathway [AP], no dual atrioventricular [AV] node): APs were present in 10 patients, AV node re-entrant tachycardia in 26 patients, and ectopic atrial tachycardia in 1 patient. Despite 3 patients, in which switching to conventional ablation was necessary (8%), all others were successfully treated using the MNS. Overall fluoroscopy amounted to a median of 3.4 minutes (interquartile range, 2.4–5.3) with only a median of 1.0 minute exposure for the investigator. Conclusions: Remote catheter ablation of SVT using the new MNS Niobe and a single conventional diagnostic catheter is feasible. Compared to conventional EP studies, a reduction of radiation exposure for both patients and investigators was demonstrated.

Remote Catheter Ablation of Parahisian Pathways. Introduction: Ablation of anteroseptal (parahisian) pathways may be difficult using conventional catheters. Methods and Results: Two patients (51 and 20 years old) underwent ablation of a parahisian accessory pathway using the magnetic navigation system Niobe® (Stereotaxis, Inc.), which consists of two external permanent magnets (0.08 Tesla) that steer a small magnet embedded in the tip of the ablation catheter. A motor drive allows the advancement or retraction of the catheter. From the control room, the ablation was performed using a single radiofrequency current application (fluoroscopy 3.2 and 6.0 minutes, respectively). Conclusions: The Niobe magnetic navigation system was successfully used to perform completely remote controlled mapping and ablation of parahisian accessory pathways.

Six weeks after left atrium appendage occlusion with a 30-mm AGA Cardiac Plug (ACP), an asymptomatic 73-year-old woman presented for routine follow-up. At the time of implant, as shown in Figure A and B, the device position satisfied the 5 signs for correct implantation: tireshaped lobe, disc/lobe separation, disc concavity, two thirds of the lobe distal to the circumflex coronary artery, and device aligned with the left atrium appendage longitudinal axis. Follow-up 2-dimensional transesophageal echocardiography revealed dislocation of the ACP device, dancing in the left atrium (Figure C; Movie I in the online-only Data Supplement). To avoid open-heart surgery, a 24-Fr steerable sheath usually used for mitral valve clipping procedures was introduced into the left atrium after transseptal puncture. Under fluoroscopy and transesophageal echocardiography guidance, the ACP device was snared by wrapping a 30-mm snare around its waist and stabilized by pulling it against the septum (Figure D and E, white arrow). Then, the distal screw of the ACP device was grabbed with a second snare (Figure E and F, black arrow) and successfully retracted into the sheath (Figure G and H; Movie II in the online-only Data Supplement). Despite a history of bleeding before the left atrium appendage occlusion therapy, the patient refused a second implantation attempt and was switched to rivaroxaban 15 mg daily. Follow-up was uneventful. The 30-mm ACP device is equipped with the same number of barbs as smaller devices despite a much larger circumfer ence being a potential reason for a higher risk of dislodgement. This will probably be solved by the new generation ACP occluder (Amulet) with an increased number of barbs.

Aim A novel third-generation cryoballoon (CB3) to perform pulmonary vein isolation (PVI) has recently been released, featuring a shortened distal balloon tip when compared with the second-generation (CB2), possibly allowing for enhanced intra-ablation pulmonary vein (PV) signal mapping. We aimed to investigate procedural efficacy and safety of the CB3 as compared to the CB2. Methods and results We studied 472 consecutive patients who underwent CB-PVI for paroxysmal or persistent atrial fibrillation (CB3: 49 patients; CB2: 423 patients). Detailed procedural data and in-hospital complications were registered in a prospective database. Complete PVI using the CB only was achieved in 98% of patients in each group. Single-freeze PVI was observed in 84/88% (CB2/CB3, P = n.s.) of the PVs. Time-to-PVI (TPVI) was 49 ± 32 (CB2) and 45 ± 27 s (CB3) ( P = n.s.). Time-to-PVI determination rate was higher in the CB3 group (89.5 vs. 82.6%, P = 0.016). Signal noise due to ice formation on mapping electrodes occurred after 70 ± 46 s using CB3 and did not interfere with TPVI determination. Exchange of the spiral mapping catheter with a guide wire was more frequently required in the CB3 group (8.2 vs. 0.7% patients, P < 0.001). Balloon dislodgement during hockey stick manoeuvres occurred in 6.1% patients of the CB3 group only ( P = 0.001). Complication rates were not different between the groups. Conclusion The CB3 offers a higher TPVI determination rate, facilitating dosing schemes based on TPVI, with equally high single-freeze efficacy compared with the CB2. The shortened distal tip of the CB3 requires adaptation of standard catheter manoeuvers to avoid balloon dislodgement.

Background Remote magnetic pulmonary vein isolation (PVI) demonstrates comparable success rate to manual ablation, but thermal effects on esophageal tissue remain undefined. Objective The purpose of this study was to evaluate the potential thermal effects on esophageal tissue during remote magnetic wide-area circumferential pulmonary vein isolation (CPVI). Methods Twenty-five patients (23 men, age 57 ± 10 years) in the magnetic navigation system (MNS) group and 25 control subjects (15 men, age 61 ± 12 years) with drug-refractory paroxysmal or persistent atrial fibrillation underwent CPVI. A magnetic 3.5-mm irrigated-tip catheter (NaviStar ThermoCool RMT, Biosense Webster) and a nonmagnetic 3.5-mm irrigated-tip catheter (NaviStar ThermoCool, Biosense Webster) were used in the MNS and control group, respectively. A temperature probe (SensiTherm, St. Jude Medical), containing 3 thermocouples was placed in close proximity to the ablation site monitoring luminal esophageal temperature (LET). LET changes did not guide therapy. Postprocedural esophagogastroduodenoscopy (EGD) was performed in all patients. Results Successful CPVI was achieved in all patients. No esophageal lesions, minimal lesions, or ulcerations were found in 16 of 25 (64%), 7 of 25 (28%), and 2 of 25 (8%) in the MNS group and in 14 of 25 (56%), 10 of 25 (40%), and 1 of 25 (4%) patients in the control group, respectively. No atrioesophageal fistula occurred. Mean maximum LET in the magnetic group was 43.7°C ± 3.7°C compared to 45.4°C ± 3.5°C in the manual control group (P = .09). Conclusion Remote magnetic PVI is associated with significant rise in LET and development of thermal esophageal lesions. In the MNS group, higher LET recordings were more likely to cause esophageal injury, whereas this association was not seen in the manual group despite a tendency toward higher mean maximum LET recordings.

Aims Manual mapping and ablation of right ventricular outflow tract (RVOT) tachycardia may be associated with cardiac perforation and complicated by mechanically induced ventricular extrasystoles (VESs). The aim of this study was to assess remote-controlled magnetic (RCM) mapping and ablation of RVOT ventricular tachycardia (VT)/VES utilizing a soft magnetic catheter. Methods and results Mapping and ablation of RVOT VT/VES were performed using the magnetic navigation system (MNS, Niobe II, Stereotaxis, St Louis, MO) in conjunction with a cardiodrive motor unit (Stereotaxis). A soft magnetic catheter (Celsius RMT, 4 mm solid tip, Biosense Webster, Diamond Bar, CA) was navigated to the RVOT using a sequence of pre-installed magnetic vectors. The primary endpoint was defined as successful RCM VT/VES ablation. Other parameters observed included RCM RVOT accessibility, mapping-induced mechanical VES, fluoroscopy time, complications, and arrhythmia recurrence. Thirteen consecutive patients (mean age: 50 ± 14 years; 10 females, 6 RVOT VT) underwent RCM mapping and ablation. The RVOT was reached in all patients utilizing solely the MNS. Successful RCM RVOT ablation was achieved in {12 of 13} (92.3%) patients. Mean procedure and fluoroscopy times were 116.5 ± 48.9 and 7.5 ± 4.3 min, respectively. Catheter-induced VES during RVOT mapping were observed in {1 in 13} patients (7.7%, three VES). No complications occurred. During a mean follow-up of 252 ± 211 days, clinical arrhythmia recurrence was observed in {1 in 13} (7.7%) patients. Conclusions Automatic RCM RVOT access is feasible, while RVOT mapping and ablation appear to be safe, fast, and effective. The soft magnetic catheter rarely induces mechanical VES.

Background High-intensity focused ultrasound (HIFU) applied via a steerable balloon catheter (ProRhythm, Ronkonkoma, NY) is a novel technology for pulmonary vein (PV) isolation. Objective The purpose of this study was to assess the short-term and long-term success rates of PV isolation in patients with paroxysmal atrial fibrillation (AF) using the steerable HIFU balloon catheter. Methods A total of 15 patients (7 female), mean age 59 ± 8 years, with a long (8 ± 5 years) history of drug-refractory, symptomatic paroxysmal AF were enrolled. After double transseptal puncture, a lasso catheter and the 16F HIFU balloon catheter (11F shaft) were inserted into the left atrium (LA). After PV angiography, phrenic nerve (PN) pacing (10 V, 2.9 ms) was conducted. In case of PN capture at the right superior PV ostium, patients were excluded (n = 3). To achieve complete PV isolation, HIFU was repeatedly applied with an acoustic power of 45 W for 40 to 90 seconds. Follow-up included telephonic interviews, transtelephonic Holter electrocardiogram, and office visits after 1, 3, and 6 months. Results Complete electrical PV isolation was achieved in 41 of 46 (89%) PVs. Median follow-up time was 387 days (range 120 to 424 days). Seven of 12 (58%) patients were free of AF without antiarrhythmic drugs. In 2 patients, only a single AF episode was documented, resulting in an overall chronic success of 75%. Despite negative PN pacing, 2 patients experienced right-sided PN palsy, which had not resolved after 12 months. Conclusion In patients with paroxysmal AF, acute PV isolation can be achieved in 89% using a steerable HIFU balloon; 58% of all patients were free of AF and 75% reached the primary end point defined as a reduction of AF episodes to less than 50%. However, further studies need to improve identification of patients at risk for PN palsy.