Remote Magnetic Catheter Navigation Research Articles

Contact force sensing manual catheter versus remote magnetic navigation ablation of atrial fibrillation: a single-center comparison

BackgroundData comparing remote magnetic catheter navigation (RMN) with manual catheter navigation in combination with contact force sensing (MCN-CF) ablation of atrial fibrillation (AF) is lacking. The primary aim of the present retrospective comparative study was to compare the outcome of RMN versus (vs.) MCN-CF ablation of AF with regards to AF recurrence. Secondary aim was to analyze periprocedural risk, ablation characteristics and repeat procedures.MethodsWe retrospectively analyzed 452 patients undergoing a total of 605 ablations of AF: 180 patients were ablated using RMN, 272 using MCN-CF.ResultsExcept body mass index there was no significant difference between groups at baseline. After a mean 1.6 ± 1.6 years of follow-up and 1.3 ± 0.4 procedures, 81% of the patients in the MCN-CF group remained free of AF recurrence compared to 53% in the RMN group (P < 0.001). After analysis of 153 repeat ablations (83 MCN-RF vs. 70 RMN; P = 0.18), there was a significantly higher reconnection rate of pulmonary veins after RMN ablation (P < 0.001). In multivariable Cox-regression analysis, RMN ablation (P < 0.001) and left atrial diameter (P = 0.013) was an independent risk factor for AF recurrence. Procedure time, radiofrequency application time and total fluoroscopy time and fluoroscopy dose were higher in the RMN group without difference in total number of ablation points. Complication rates did not differ significantly between groups (P = 0.722).ConclusionsIn our retrospective comparative study, the AF recurrence rate and pulmonary vein reconnection rate is significantly lower with more favorable procedural characteristics and similar complication rate utilizing MCN-CF compared to RMN.

Catheter ablation for ventricular arrhythmias using remote magnetic navigation in patients with reduced ejection fraction

Objective. Radiofrequency catheter ablation is an effective treatment option for cardiac arrhythmias including complex and ventricular arrhythmias. Remote magnetic catheter navigation (RMN) has been developed as a novel way of approach aiming to improve outcome and reduce complication rate, and reduce radiation exposure for both operator and patient. Our aim was to compare success and complication rate in patients with or without severely reduced left ventricular ejection fraction (LVEF). Methods. We retrospectively analyzed all the patients (n = 98) which have undergone RMN in our center between 2015-2021. No selection criteria for RMN procedure have been applied. All clinical and paraclinical, as well as procedural data were collected. Patients were divided into two groups, with or without severely reduced LVEF ≤ 35%. CARTO system was used for 3D electroanatomic mapping. RMN was done using Niobe ES system and an open-irrigated magnetic ablation catheter. Success rate was defi ned by complete elimination of clinical arrhythmia. Non-inducibility following ablation was assessed in all patients presenting with any type of ventricular arrhythmia other than premature ventricular contractions. Testing for inducibility was done by ventricular programmed pacing with up to four extra-stimuli. The statistical analysis was performed using SPSS software. P-value &lt; 0.05 was considered signifi cant. Results. Successful ablation with complete elimination of the clinical arrhythmia was achieved in 92.3% of the patients with severely reduced LVEF and in 88.1% of patients with LVEF &gt; 35% (p = 0.73). Overall minor complication rate was 2.04% with spontaneous resolution. No major complications were reported. Non-inducibility was achieved in 56.4% of the patients with LVEF ≤ 35% and in 79.2% of the patients with LVEF &gt;35% (p = 0.023). Conclusion. Radiofrequency catheter ablation using RMN is effective and safe regardless of the presence or not of a severely reduced LVEF.

Electrocardiogram Acquisition During Remote Magnetic Catheter Navigation.

Electrocardiogram (ECG) acquisition is required during catheter treatment of cardiac arrhythmias. The remote magnetic navigation technology allows the catheter to be moved automatically inside the heart chambers using large external magnets. Each change of position of the catheter requires fast motion of the magnets, therefore magnetic fluxes are created through the ECG cables, causing large distortions of the ECG signals. In this study a novel ECG sensor is proposed for reducing such distortions. The sensor uses short cables to connect the electrodes to the amplification and optical conversion circuit, using a technology similar to that used for magnetic resonance imaging. The proposed sensor was compared to the conventional 12-lead ECG device during various operation modes of the magnets. Quantitative morphological analysis of the different waves of the ECG was performed in two healthy subjects and on a conductivity phantom reproducing various cardiac pathologies. In healthy subjects the beat-to-beat correlation coefficients were improved with the proposed sensor for the PR interval (80-93% vs. 49-89%), QRS complex (93-96% vs. 74-94%), ST segment + T wave (95-98% vs. 67-99%), and whole PQRST wave (82-97% vs. 55-96%). Similar observations were made with the conductive gel in the whole PQRST wave in the pathological morphologies of the ECG for the VT (99% vs. 56-98%), AT (95% vs. 26-89%), STE (96-97% vs. 20-91%) and STD (96% vs. 28-90%). The new sensor might be used for better (uninterrupted) monitoring of the patient during catheter interventions using remote magnetic navigation. It has the potential to improve the robustness and/or duration of certain clinical procedures such as ventricular tachycardia ablation.

Long-term outcomes of the current remote magnetic catheter navigation technique for ablation of atrial fibrillation

Objectives. Comparisons between remote magnetic (RMN) and manual catheter navigation for atrial fibrillation (AF) ablation have earlier been reported with controversial results. However, these reports were based on earlier generations of the RMN system. Design. To evaluate the outcomes of the most current RMN system for AF ablation in a larger patient population with longer follow-up time, 112 patients with AF (78 paroxysmal, 34 persistent) who underwent AF ablation utilizing RMN (RMN group) were compared to 102 AF ablation patients (72 paroxysmal, 30 persistent) utilizing manual technique (Manual group). Results. The RMN group was associated with significantly shorter fluoroscopy time (10.4 ± 6.4 vs. 16.3 ± 10.9 min, p < .001) but used more RF energy (64.1 ± 19.4KJ vs. 54.3 ± 24.1 KJ, p < .05), while total procedure time showed no significant difference (201 ± 35 vs. 196 ± 44 min, NS). After 39 ± 9/44 ± 10 months of follow-up, AF-free rates at 1year, 2 years and 3.5 years post ablation were 63%, 46% and 42% in the RMN group vs. 60%, 32% and 30% (survival analysis p < .05) in the Manual group, whereas clinically effective rates were 82%, 73% and 70% for the former vs. 70%, 56% and 49% for the latter (survival analysis p < .005). Conclusion. Differing from previous reports, our data from a larger patient population and longer follow-up time demonstrates that compared to manual technique, the most current RMN technique is associated with better procedural and clinical outcomes for AF ablation.

Remote magnetic catheter navigation versus conventional ablation in atrial fibrillation ablation: Fluoroscopy reduction

BackgroundPercutaneous transcatheter radiofrequency ablation of atrial fibrillation with remote controlled magnetic navigation (RMN) has been shown to reduce radiation exposure to patients and physicians compared with conventional manual (MAN) ablation techniques. MethodsCatheter ablation for atrial fibrillation was performed utilizing RMN in 214 consecutive patients and MAN ablation techniques in 229 patients. We compared the fluoroscopy and procedural times between RMN and MAN catheter ablation of atrial fibrillation. Secondary objectives included comparing acute procedural success and short-term complication rates between both ablation strategies. ResultsFluoroscopy time was significantly shorter in the RMN group than the MAN group (53.5±30.1 vs 68.1±27.6min, respectively; p<0.01); however, the total procedural time was longer in the RMN group (280.2±74.4min vs 213.1±64.75, respectively; p>0.001). Further subgroup analysis of the most recent 50 ablations each from the RMN and MAN groups, to attenuate the RMN learning curve effect, showed an even greater difference in fluoroscopy time (RMN vs MAN: 53.5±30.1 vs 68.1±27.6min), though a consistently longer procedure time with RMN (249.5±65.5 vs 186.3±65.6min, respectively). The acute procedural success rate was comparable between the groups (98.6% vs 95.6%, respectively; p=0.07). The rates of acute complications were similar in both groups (2.3% vs 4.8%, respectively; p=0.16). ConclusionsIn radiofrequency ablation of atrial fibrillation, RMN appears to significantly reduce fluoroscopy time compared with conventional MAN ablation, though at a cost of increased total procedural time, with comparable acute success rates and safety profile. A reduction in procedure and fluoroscopy times is possible with gaining experience.

COMPARISON OF REMOTE MAGNETIC CATHETER NAVIGATION WITH MANUAL TECHNIQUE FOR CATHETER ABLATION OF ATRIAL FIBRILLATION: A SINGLE CENTER STUDY

Comparisons between remote magnetic navigation (RMN) and manual catheter navigation (Manual) for ablation of atrial fibrillation (AF) have earlier been reported with controversial results. We aim to compare the efficacy and outcome of these two methods for AF ablation based on our data from a larger

Catheter Ablation of Complex Tachyarrhythmias Using Remote Magnetic Catheter Navigation System

Catheter Ablation of Complex Tachyarrhythmias Using Remote Magnetic Catheter Navigation System

Non-Fluoroscopic Transseptal Catheterization During Electrophysiology Procedures using a Remote Magnetic Navigation System.

Transseptal punctures are commonly performed, and left atrial (LA) access is frequently lost during lengthy, complex electrophysiology (EP) procedures. We describe a new technique for non-fluoroscopic re-crossing the fossa ovalis using a new multielectrode transseptal sheath (TS) and a new remote magnetic catheter navigation system (RMNS) (CGCI System, Magnetecs) that uses 8 rapid external electromagnets for real-time navigation of a magnet-tipped electrode catheter across the initial transseptal puncture site in 5 patients undergoing left-sided ablation procedures. The three-dimensional (3D) position of a 8.5 Fr steerable TS with 5-ring 5-15-15-5-mm spaced distal electrodes (Agilis ES©, St Jude Medical), and site of fossal ovalis crossing were "shadowed landmarks" on a 3D electroanatomic mapping (EAM) system (EnSite/NavXTM, St Jude Medical). The TS-magnetic ablation catheter assembly was pulled-back to the inferior vena cava. EAM landmarks were used with RMNS-guided "manual" and "automated" catheter navigation modalities, until septal crossing was obtained. Transseptal re-crossing was successfully performed in all patients in 6.2±8.1 sec using the "automated" RMNS-guided technique and in 30.4±28.4 sec using the "manual" RMNS-guided technique (p=0.01) without complications. This new RMNS was safely and effectively used to perform non-fluoroscopic transseptal catheterization.

Remote magnetic catheter navigation: more than just bells and whistles ?

Catheter ablation is nowadays an established treatment modality for both atrial and ventricular tachyarrhythmias. Manual navigation of the ablation catheter can be challenging in patients with a complex cardiac anatomy due to, for example, (surgically corrected or palliated) congenital heart defects, resulting in a long procedure time and excessive X-ray exposure. In the past decades, sophisticated mapping and ablation techniques have been developed in order to improve the outcome of ablative therapy. These technologies include remote navigation systems such as the magnetic navigation system (Stereotaxis Inc.) and the non-magnetic robotic navigation system (Sensei Hansen Medical). In this issue, Roudijk et al. report on the value of remote magnetic catheter navigation and ablation in children and young adult patients with and without congenital heart disease in their paper entitled: ‘Catheter ablation in children and young adults: is there an additional benefit from remote magnetic navigation [1]? In this elegant paper, the outcome of ablative therapy of a variety of tachyarrhythmias was examined.

Long‐Term Efficacy of Single Procedure Remote Magnetic Catheter Navigation for Ablation of Ischemic Ventricular Tachycardia: A Retrospective Study

Remote magnetic navigation (RMN) aims to reduce some inherent limitations of manual radiofrequency (RF) ablation. However, data comparing the effectiveness of both methods are scarce. This study evaluated the acute and long-term success of RMN guided versus manual RF ablation in patients with ischemic sustained ventricular tachycardia (sVT). One hundred two consecutive patients (age 68 ± 10 years, LVEF 32 ± 12%, 88 men) with ischemic sVT were ablated with RMN (Stereotaxis; 49%) or manually (51%) using substrate and/or activation mapping (Carto) and open-irrigated-tip catheters. All received implantable defibrillators or loop recorders. Acute success was defined as noninducibility of any sVT at the end of the ablation procedure and long-term success as freedom from VT upon follow-up. There was no difference in the baseline characteristics between the groups. Three patients died in hospital. Acute success rate was similar for RMN and manual ablation (82% vs 71%, P = 0.246). RMN was associated with significantly shorter fluoroscopy time (13 ± 12 minutes vs 32 ± 17 minutes, P = 0.0001) and RF time (2337.59 ± 1248.22 seconds vs 1589.95 ± 1047.42 seconds, P = 0.049), although total procedure time was similar (157 ± 40 minutes vs 148 ± 50 minutes, P = 0.42). There was a nonsignificant trend toward better long-term success in RMN group: after a median of 13 (range 1-34) months, 63% in the RMN and 53% in the manual ablation group were free from VT recurrence (P = 0.206). RMN guided RF ablation of ischemic sustained VT is equally efficient compared with manual ablation in terms of acute and long-term success rate. These results are achieved with a significantly reduced fluoroscopy time and shorter RF time.

Remote magnetic navigation for atrial fibrillation ablation: is 'As Good as Manual' good enough

This editorial refers to ‘Catheter ablation of atrial fibrillation using remote magnetic catheter navigation: a case–control study’ by A. Arya et al. , on page 45 Remote magnetic navigation for arrhythmia procedures has been performed since 2004. It has been shown to be useful in a variety of ablation procedures such as supraventricular tachycardia, ventricular tachycardia, epicardial ablation, and atrial fibrillation.1–5 The navigation technology is remarkable in that it has the ability to magnetically direct the tip of a floppy catheter, allowing the system to perform procedures that are difficult for some operators with manual navigation catheters. The system has also brought the ability to perform automated navigation and ablation to a specialty dominated by hands-on procedures. One of the most difficult challenges of the new technology is performing the same procedures safely. Remote magnetic navigation has demonstrated a fantastic safety record, including in the paper published by Arya et al .6 Unfortunately, all that glitters is not gold. One of the main limitations of the system has been the delay in modern ablation technology being available for use with the system. As the …

Catheter ablation of atrial fibrillation using remote magnetic catheter navigation: a case-control study

To compare the acute and the 6 month outcome of catheter ablation of atrial fibrillation (AF) using irrigated tip magnetic catheter and remote magnetic cathter navigation (RMN) with manual catheter navigation (MCN) in patients with paroxysmal and persistent AF. In this retrospective analysis 356 patients (235 male, mean age: 57.9 ± 10.9 years) with AF (70.5%, paroxysmal) who underwent catheter ablation between August 2007 and May 2008 using either RMN (n = 70, 46 male, mean age: 57.9 ± 10.1 years, 50% paroxysmal) or MCN (n = 286, 189 male, mean age: 58.0 ± 13.9 years, 75.5% paroxysmal) were included. All patients completed an intensive follow-up strategy. Complete pulmonary vein isolation was achieved in 87.6 and 99.6% of patients in RMN and MCN groups, respectively (P < 0.05). The procedure, fluoroscopy, and radiofrequency application times were 223 ± 44 vs. 166 ± 52 min (P < 0.0001), 13.7 ± 7.8 vs. 34.5 ± 15.1 min (P < 0.0001), and 75.4 ± 20.9 vs. 53.2 ± 21.4 min (P < 0.0001) in RMN and MCN groups, respectively. Seven (10.0%) and 28 (9.8%) patients in RMN and MCN groups received antiarrhythmic medications during the follow-up (P = 0.96). All the patients completed the 6 month follow-up. Freedom from AF at 6 months was achieved in 57.8 and 66.4% of the patients in RMN and MCN groups, respectively (P = 0.196). In patients without previous AF catheter ablation procedure the freedom from AF at 6 months were 68.2 and 60.5% in the MCN and RMN groups, respectively (P = 0.36). Catheter ablation using irrigated tip magnetic catheter and RMN is an effective and safe method for catheter ablation of AF. Compared to manual catheter navigation, the procedure and radiofrequency application times were longer and fluoroscopy time was shorter in the RMN group compared with the MCN group.

Interference of remote magnetic catheter navigation and ablation with implanted devices for pacing and defibrillation

Remote magnetic catheter navigation (RMN) may facilitate catheter ablation. However, as the system uses permanent magnets, interference (INF) with devices for pacing [pacemaker (PM)], defibrillation [implantable cardioverter defibrillators (ICD)], or cardiac resynchronisation [cardiac resynchronization therapy (CRT)] may occur. We investigated the effects of the RMN system on implanted arrhythmia devices in a prospective series. Prior to RMN-guided electrophysiological procedures, devices were fully interrogated and programmed to VVI 40/min with tachycardia detection off (if applicable). Periprocedural device performance was monitored by 12-lead electrocardiogram, and duration and effect of asynchronous stimulation resulting from INF were evaluated. Following the procedure, devices were again interrogated and system integrity verified. A total of 21 procedures in 18 patients with implanted devices [PM n = 12, ICD n = 3, CRT-pacemaker (P) n = 1, CRT-defibrillation (D) n = 2] were evaluated. No relevant changes in lead parameters or device programming were observed after the procedure. No INF was noted in ICD/CRT-D devices (tachycardia detection off) and in 2 PMs, whereas 10 PMs and 1 CRT-P switched to asynchronous stimulation for 1.8 ± 0.3 h (63 ± 13% of RMN duration) without clinical adverse effects. In one patient, ventricular tachycardia (VT) degenerating in ventricular fibrillation occurred, but no causal relation between INF and VT initiation could be ascertained. This prospective data provide no evidence that using RMN in patients with implanted arrhythmia devices may cause persistent device dysfunction. Asynchronous PM stimulation is common without negative clinical consequences. Although a causal role of INF for the VT observed seems unlikely, risks and benefits of RMN utilization should carefully be weighed for each patient with an implanted arrhythmia device.

Catheter Ablation of Scar-Related Ventricular Tachycardia in Patients with Electrical Storm Using Remote Magnetic Catheter Navigation

A remote magnetic navigation system (MNS) has been used for ablation of ventricular arrhythmias. However, irrigated tip catheter has not been evaluated in large series of patients. To evaluate acute and long-term efficiency of the newly available irrigated tip magnetic catheter for radiofrequency (RF) ablation of scar-related ventricular tachycardia (VT) in patients with ischemic heart disease. Between January 2008 and October 2009, a total of 30 consecutive patients with ischemic heart disease (26 men, age 70.1 ± 8.7 years, left ventricular ejection fraction: 30 ± 9%) and electrical storm due to monomorphic VT underwent RF ablation using a remote MNS and a magnetic irrigated tip catheter. Acute success was defined as noninducibility of any monomorphic VT during programmed right and left ventricular stimulation, and obtained in 24 (80%) patients. A total of 1-6 VTs (mean 2.3 ± 1.2, 394 ± 108 ms, 210-660 ms) were inducible during each procedure. The duration of RF energy application was 41.2 ± 23.3 minutes, with total procedure and fluoroscopy times of 158 ± 47 minutes and 9.8 ± 5.3 minutes, respectively. No acute complications were observed during the procedures. During mean follow-up of 7.8 months, 21 patients (70%) had no recurrence of VT and received no implantable cardioverter defibrillator therapy. Among patients who were noninducible during programmed right ventricular stimulation (n = 25), ≥1 monomorphic VT was inducible during programmed left ventricular stimulation in four (16%) that was ablated successfully in three of them. Irrigated ablation of scar-related VT using remote MNS is an effective modality for management of the monomorphic VT in patients with ischemic cardiomyopathy with minimal radiation exposure. Programmed left (in addition to right) ventricular stimulation might be necessary to assess acute outcome of the ablation procedure.

Six-month follow-up of isthmus-dependent right atrial flutter ablation using a remote magnetic catheter navigation system: a case-control study

Objective— The objective of this study was to compare results between the magnetic navigation system (MNS) and conventional catheter ablation of cavo-tricuspid isthmus (CTI)-dependent right atrial flutter (AFL) in a case control study.Background— A remote MNS has been used for ablation of various arrhythmias including CTIdependent AFL but comparative results between MNS and conventional ablation are not available.Methods— Between May and September 2007, a total of 51 consecutive patients (45 men, mean age 65.4 ± 9.4 years) had undergone catheter ablation for CTI-dependent AFL.The catheter ablation (70°C, 70 W, 90 s) was performed with either an 8-mm-tip magnetic catheter using MNS (case group, n = 26, 23 men, mean age 64.6 ± 9.6 y) or a conventional 8-mm catheter (case group, n = 25, 22 men, mean age 65.4 ± 9.1 y). Acute procedural success was defined as complete bidirectional isthmus block and success at six months was defined as absence of AFL during the six months follow-up.Results— With respect to baseline characteristics there were no differences between the two groups.The procedure time in MNS and conventional group was [median (range)] 53 (30-130) min and 45 (30-100) min, respectively (P= 0.12). Acute success was achieved by MNS and conventional ablation in 25/26 (96.2%) and 25/25 (100%) of patients, respectively (P= 0.53). During the six months of follow-up 4 patients, 2 in each group, experienced recurrence (P= 0.90). No major complication occurred during the procedure. Charring on the catheter tip occurred in 5 patients (19.2%) in MNS and none of the patients in the control group (P < 0.05).Conclusion— This case-control study demonstrated the acute and mid-term efficacy and safety of catheter ablation by MNS for CTI-dependent AFL, similar to rates achieved by conventional radiofrequency catheter ablation.

Safety of Remote Magnetic Navigation in Patients With Pacemakers and Implanted Cardioverter Defibrillators

Remote magnetic catheter navigation (MNS) has been shown to be feasible and safe for radiofrequency catheter ablation of various cardiac arrhythmias. However, its safety in patients with implanted pacemakers or cardioverter-defibrillators has not yet been studied. This retrospective case series study intends to assess the acute and short-term safety of remote MNS in patients with implanted pacemakers or cardioverter-defibrillators. Between January 2008 and June 2009, a total of 31 patients with implanted pacemakers (n = 5) or cardioverter-defibrillators (n = 26) underwent 32 catheter ablation procedures using the remote MNS. Baseline pacing thresholds, sensed amplitudes, pacing and, if available, shock impedances as well as battery status were measured in all devices before, immediately after, and 1-3 months after catheter ablation. After ablation, no statistically significant difference in atrial sensing (2.7 ± 1.5 mV vs 3.1 ± 1.9 mV, P = 0.18) and impedance (457 ± 104 Ω vs 449 ± 101 Ω, P = 0.37) were observed. After ablation, no statistically significant difference in right ventricular sensing (10.4 ± 3.8 mV vs 10.9 ± 4.9 mV, P = 0.43) and impedance (535 ± 118 Ω vs 534 ± 120 Ω, P = 0.913) were observed. No changes in pacing threshold could be observed in all but 2 patients with biventricular cardioverter-defibrillators who underwent ventricular tachycardia ablation in lateral wall of left ventricle near the implanted epicardial electrode. Ablation procedures using remote MNS can be performed safely in patients with implanted devices with no significant effects on device system integrity. Long endocardial ablation close to the insertion site of the implanted epicardial left ventricular leads can affect the pacing and/or sensing characteristics of these electrodes.

Remote Magnetic Catheter Navigation for Cavotricuspid Isthmus Ablation in Patients With Common-Type Atrial Flutter

Conventional catheter ablation of cavotricuspid isthmus (CTI)-dependent atrial flutter is a widely applied standard therapy. Remote magnetic catheter navigation (RMN) may provide benefits for different ablation procedures, but its efficacy for CTI ablation has not been evaluated in a randomized, controlled trial. Ninety patients undergoing de novo ablation of atrial flutter were randomly assigned to conventional manual (n=45) or RMN-guided (n=45) CTI ablation with an 8-mm-tip catheter. Complete bidirectional isthmus block was achieved in 84% (RMN) and 91% (conventional catheter ablation) of the cases (P=0.52). RMN was associated with shorter fluoroscopy time (median, 10.6 minutes; interquartile range [IQR], 7.6 to 19.9, versus 15.0 minutes; IQR, 11.5 to 23.1; P=0.043) but longer total radiofrequency application (17.1 minutes; IQR, 8.6 to 25, versus 7.5 minutes; IQR, 3.6 to 10.9; P<0.0001), ablation time (55 minutes; IQR, 28 to 76, versus 17 minutes; IQR, 7 to 31; P<0.0001), and procedure duration (114+/-35 versus 77+/-24 minutes, P<0.0001). Procedure duration in the RMN group did not decrease significantly with case experience. Long-term procedure success, defined as achievement of complete CTI block and freedom from atrial flutter recurrence during 6 months of follow-up, was lower in the RMN group (73% versus 89%, P=0.063). Right atrial angiography after ablation revealed no significant differences between groups in terms of right atrial diameter or CTI length, morphology, and angulation. Furthermore, none of these parameters was predictive for difficult (ablation time >20 minutes) or unsuccessful ablation. RMN-guided CTI ablation is associated with reduced radiation exposure but prolonged ablation and procedure times as compared with conventional catheter navigation. Our findings suggest that ablation lesions produced with an RMN-guided 8-mm catheter are less effective irrespective of CTI anatomy. clinicaltrials.gov Identifier: NCT00560872.

Impact of Remote Magnetic Catheter Navigation on Ablation Fluoroscopy and Procedure Time

Remote magnetic catheter navigation (RCN) is gaining acceptance in clinical cardiac electrophysiology, but details regarding how RCN affects procedure execution are not well characterized. From January 1, 2005, to November 30, 2007, 721 cases were retrospectively analyzed and compared. Of these, 127 used RCN and 594 used manual catheter navigation (MCN). Data including procedure time, fluoroscopy time, ablation catheter, procedural success, and complications were extracted from our procedure database and compared between RCN and MCN. RCN use significantly decreased fluoroscopy time for atrial fibrillation (AF) ablation (-29 minutes, P < 0.001), atrioventricular nodal reentrant tachycardia ablation (-14 minutes, P < 0.001), and atrioventricular reentrant tachycardia ablation (-18 minutes, P = 0.045). While RCN significantly increased mean procedure time for AF (+36 minutes, P = 0.003) and atypical atrial flutter cases (+116 minutes, P = 0.016), RCN AF procedure time diminished with increasing number of cases performed. Two cases of tamponade occurred during AF ablation using MCN (2.2%, 2 of 91 cases). No tamponade occurred during all 75 AF ablations with RCN. RCN can reduce fluoroscopy time and may reduce complications during catheter ablation. While it may increase total procedure duration, procedure times decrease with increasing operator experience. (PACE 2008; 31:1399-1404).

Remote Magnetic Versus Manual Catheter Navigation for Ablation of Supraventricular Tachycardias: A Randomized, Multicenter Trial

The potential benefits of remote robotic navigation for catheter ablation procedures have not been demonstrated in controlled clinical trials. The purpose of this study was to compare remote magnetic catheter navigation to manual navigation for the ablation of common supraventricular arrhythmias. Patients with supraventricular arrhythmias due to atrioventricular (AV) nodal reentry, accessory pathways, or undergoing AV junctional ablation for complete heart block were randomized in a 3:1 ratio between magnetic (Niobe system and Helios II catheter, Stereotaxis, Inc., St. Louis, MO) and manual navigation for radiofrequency ablation at 13 centers. The primary endpoint of the study was total fluoroscopic time. Fifty-six patients were randomized to magnetic navigation and 15 to manual navigation. AV nodal reentry was the most common arrhythmia in both groups. Total fluoroscopy time was reduced in the magnetic navigation group (median 17.8 minutes, interquartile (IQ) range 9.9,27.8 minutes) compared to manual navigation (27.1, IQ 19.0,48.0, P < 0.05). The acute success rates (91% for magnetic and 87% for manual navigation, P > 0.05) did not differ between groups. The number of lesions delivered was less for magnetic navigation (6, IQ 4,9 vs 10, IQ 7, 26, P < 0.05). Total procedure time (median 151, IQ 111, 221 minutes magnetic and 151, IQ 110, 221 minutes manual) and complication rates (5.4% patients magnetic and 6.7% patients manual) were similar between the groups (both P > 0.05). Remote magnetic catheter navigation reduces fluoroscopic time and radiofrequency lesion deliveries for the ablation of common supraventricular arrhythmias compared to manual catheter navigation.

Initial Clinical Experience with a Remote Magnetic Catheter Navigation System for Ablation of Cavotricuspid Isthmus‐Dependent Right Atrial Flutter

A remote magnetic navigation system (MNS) is available and has been used with a 4-mm-tip magnetic catheter for radiofrequency (RF) ablation of some supraventricular and ventricular arrhythmias; however, it has not been evaluated for the ablation of cavotricuspid isthmus-dependent right atrial flutter (AFL). The present study evaluates the feasibility and efficiency of this system and the newly available 8-mm-tip magnetic catheter to perform RF ablation in patients with AFL. Twenty-six consecutive patients (23 men, mean age 64.6 +/- 9.6 years) underwent RF ablation using a remote MNS. RF ablation was performed with an 8-mm-tip magnetic catheter (70 degrees C, maximum power 70 W, 90 seconds). The endpoint of ablation was complete bidirectional isthmus block. To assess a possible learning curve, procedural data were compared between the first 14 (group 1) and the rest (group 2) of the patients. The initial rhythm during ablation was AFL in 20 (19 counterclockwise and 1 clockwise) and sinus rhythm in six patients. Due to technical issues, the ablation in the 18th patient could not be done with the MNS, and so we switched to conventional ablation. The remote magnetic navigation and ablation procedure was successful in 24 of the 25 (96%) remaining patients with AFL. In one patient (patient 2), conventional catheter was used to complete the isthmus block after termination of AFL. The procedure, preparation, ablation, and fluoroscopy times (median [range]) were 53 (30-130) minutes, 28 (10-65) minutes, 25 (12-78) minutes, and 7.5 (3.2-20.8) minutes, respectively. Patients in group 2 had shorter procedure (45 [30-70] min vs 80 [57-130] min, P = 0.0001), preparation (25 [10-30] min vs 42 [30-65] min, P = 0.0001), ablation (20 [12-40] min vs 31 [20-78] min, P = 0.002), and fluoroscopy (7.2 [3.2-12.2] min vs 11.0 [5.4-20.8] min, P = 0.014) times. No complication occurred during the procedure. Using a remote MNS and an 8-mm-tip magnetic catheter, ablation of AFL is feasible, safe, and effective. Our data suggest that there is a short learning curve for this procedure.