Remote Magnetic Navigation Research Articles

Accelerated idioventricular rhythm requiring catheter ablation in a child: The dark side of a benign arrhythmia

A 12 year-old boy, with no history of cardiac disease, was referred to our department for evaluation of an incessant accelerated idioventricular rhythm (AIVR) complicated with severe left ventricular (LV) dysfunction and cardiogenic shock. Extensive diagnostic work-up failed to reveal any structural heart disease. During electrophysiological study, AIVR originated from the right ventricular endocardial anterior wall and was successfully ablated using remote magnetic navigation. LV function showed complete recovery four weeks after the procedure. This case highlights a life-threatening evolution of an arrhythmia generally presented as a benign entity in children.

GW28-e1223 Remote magnetic navigation vs. manual navigation for catheter ablation of paroxysmal atrial fibrillation

GW28-e1223 Remote magnetic navigation vs. manual navigation for catheter ablation of paroxysmal atrial fibrillation

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.

Initial experience of a novel mapping system combined with remote magnetic navigation in the catheter ablation of atrial fibrillation.

There have been advancements of sophisticated mapping systems used for ablation procedures over the last decade. Utilization of these novel mapping systems in combination with remote magnetic navigation (RMN) needs to be established. We investigated the new EnSite Precision mapping system (St. Jude Medical, Inc., St. Paul, MN, USA), which collects magnetic data for checking navigation field stability and is built on an open platform, allowing physicians to choose diagnostic and ablation catheters. We address its compatibility with RMN. To assess the clinical utility of a novel 3D mapping system (EnSite Precision mapping system) combined with RMN (Niobe ES, Stereotaxis, Inc., St. Louis, MO, USA) for atrial fibrillation (AF) ablation. In this prospective nonrandomized study, two groups of patients were treated in our center for drug refractory AF. Patients were consecutively enrolled in each group. Group A (n=35, 14 persistent AF [PsAF]) was treated using the novel 3D mapping system combined with RMN. Group B (n=38, 16 PsAF) was treated using Carto® 3 (Biosense Webster, Inc., Diamond Bar, CA, USA) combined with RMN. In Group A, the left atrium (LA) was mapped with a circular magnetic catheter manually and was then replaced by a RMN ablation catheter. At the end of the procedures in Group A, the circular catheter was used for confirming field stability. In Group B, an ablation catheter was controlled by RMN to perform both LA mapping and ablation. All patients underwent pulmonary vein antrum isolation. Additional complex fractionated atrial electrograms (CFAEs) ablation was performed for PsAF. Procedural, ablation, and fluoroscopy times were recorded and complications were assessed. Electrophysiological end points were achieved in all patients. Using the novel mapping system, LA mapping time was fast (308 ± 60 seconds) with detailed anatomy points (178,831 ± 70,897) collected and magnetic points throughout LA. At the end of the procedures in Group A, the LA model was confirmed to be stable and its location was within the distance threshold (1mm). Procedure time (117.9 ± 29.6minutes vs. 119.2 ± 29.7minutes, P=0.89), fluoroscopy time (6.1 ± 2.4minutes vs. 4.8 ± 2.2minutes, P=0.07), and ablation time (28.0 ± 12.9minutes vs. 27.9 ± 15.8minutes, P=0.98) were similar in Group A versus Group B, respectively. No complications occurred in either group. LA mapped by the novel system is stable and reliable. Combined with RMN, it could be effectively used for AF ablation without impacting overall procedural times.

Multicenter, randomized comparison between magnetically navigated and manually guided radiofrequency ablation of atrioventricular nodal reentrant tachycardia (the MagMa-AVNRT-trial).

Remote magnetic navigation (RMN) is attributed to diminish radiation exposure for both patient and operator performing catheter ablation for different arrhythmia substrates. The purpose of this prospective, randomized study was to compare RMN with manually guided catheter ablation for AV nodal reentrant tachycardia (AVNRT) regarding fluoroscopy time/dosage, acute and long-term efficacy as well as safety. A total of 218 patients with AVNRT undergoing catheter ablation at three centers (male 34%, mean age 50±17years) were randomized to a manual approach (n=113) or RMN (n=105) using the Niobe® magnetic navigation system. The primary study endpoint was total fluoroscopy time/dosage for patient and operator at the end of the procedure. Secondary endpoints included acute success, procedure duration, complications and success rate after 6months. Fluoroscopy time and dosage for the patient were significantly reduced in the RMN group compared to the manual group (6±6 vs. 11±10min; p<0.001 and 425±558 vs. 751±900 cGycm2, p=0.002). A reduction in fluoroscopy time/dose also applied to the operator (3±5 vs. 7±9min 209±444 vs. 482±689 cGycm2, p<0.001). Procedure duration was significantly longer in the RMN group (88±29 vs. 79±29min; p=0.03) and crossover from the RMN group to manual ablation occurred in 7.6% of patients (7.6 vs. 0.1%; p=0.02). Acute success was achieved in 100% of patients in both groups. Midterm success after 6months was 97 vs. 98% (p=0.67). No complications occurred in both groups. The use of RMN for catheter ablation of AVNRT compared to a manual approach results in a reduction of fluoroscopy time and dosage of about 50% for both patients and physicians. Acute and midterm success and safety are comparable. RMN is a good alternative to a manual approach for AVNRT ablation.

Prediction and prognosis of ventricular tachycardia recurrence after catheter ablation with remote magnetic navigation for electrical storm in patients with ischemic cardiomyopathy.

Ventricular tachycardia (VT) recurrence after catheter ablation for electrical storm is commonly seen in patients with ischemic cardiomyopathy (ICM). We hypothesized that VT recurrence can be predicted and be related to the all-cause death after VT storm ablation guided by remote magnetic navigation (RMN) in patients with ICM. A total of 54 ICM patients (87% male; mean age, 65 ± 7.1 years) presenting with VT storm undergoing acute ablation using RMN were enrolled. Acute complete ablation success was defined as noninducibility of any sustained monomorphic VT at the end of the procedure. Early VT recurrence was defined as the occurrence of sustained VT within 1 month after the first ablation. After a mean follow-up of 17.1 months, 27 patients (50%) had freedom from VT recurrence. Sustained VT recurred in 12 patients (22%) within 1 month following the first ablation. In univariate analysis, VT recurrence was associated with incomplete procedural success (hazard ratio [HR]: 6.25, 95% confidence interval [CI]: 1.20-32.47, P = 0.029), lack of amiodarone usage before ablation (HR: 4.71, 95% CI: 1.12-19.7, P = 0.034), and a longer procedural time (HR: 1.023, 95% CI: 1.00-1.05, P = 0.05). The mortality of patients with early VT recurrence was higher than that of patients without recurrence (P < 0.01). Inducibility of any VT at the end of procedure for VT storm guided by RMN is the strongest predictor of VT recurrence. ICM patients who have early recurrences after VT storm ablation are at high risk of all-cause death.

4987Ventricular tachycardia critical isthmus detection through pacemapping technique guided by a robotic magnetic navigation system

4987Ventricular tachycardia critical isthmus detection through pacemapping technique guided by a robotic magnetic navigation system

Remotely navigated ablation of RVOT tachycardia

Ablation of tachycardia and premature ventricular contractions originating from the right ventricular outflow tract can safely be performed in patients with normal anatomy via the femoral approach. We present a case of catheter ablation in the right ventricular outflow tract in a patient with a venous malformation of the inferior vena cava by means of remote magnetic navigation via the internal jugular vein.

P307Impact of catheter ablation guided by remote magnetic navigation on atrial fibrillation in patients with impaired left ventricular systolic function

P307Impact of catheter ablation guided by remote magnetic navigation on atrial fibrillation in patients with impaired left ventricular systolic function

P306Initial experience of a novel mapping system combined with remote magnetic navigation in the catheter ablation of atrial fibrillation

P306Initial experience of a novel mapping system combined with remote magnetic navigation in the catheter ablation of atrial fibrillation

P391Current role and further prospective of catheter ablation of ventricular arrhythmias using Remote Magnetic Navigation: A single center observational study

P391Current role and further prospective of catheter ablation of ventricular arrhythmias using Remote Magnetic Navigation: A single center observational study

An efficient cardiac mapping strategy for radiofrequency catheter ablation with active learning

ObjectiveA major challenge in radiofrequency catheter ablation procedures is the voltage and activation mapping of the endocardium, given a limited mapping time. By learning from expert interventional electrophysiologists (operators), while also making use of an active-learning framework, guidance on performing cardiac voltage mapping can be provided to novice operators or even directly to catheter robots.MethodsA learning from demonstration (LfD) framework, based upon previous cardiac mapping procedures performed by an expert operator, in conjunction with Gaussian process (GP) model-based active learning, was developed to efficiently perform voltage mapping over right ventricles (RV). The GP model was used to output the next best mapping point, while getting updated towards the underlying voltage data pattern as more mapping points are taken. A regularized particle filter was used to keep track of the kernel hyperparameter used by GP. The travel cost of the catheter tip was incorporated to produce time-efficient mapping sequences.ResultsThe proposed strategy was validated on a simulated 2D grid mapping task, with leave-one-out experiments on 25 retrospective datasets, in an RV phantom using the Stereotaxis Niobe® remote magnetic navigation system, and on a tele-operated catheter robot. In comparison with an existing geometry-based method, regression error was reduced and was minimized at a faster rate over retrospective procedure data.ConclusionA new method of catheter mapping guidance has been proposed based on LfD and active learning. The proposed method provides real-time guidance for the procedure, as well as a live evaluation of mapping sufficiency.

Catheter Ablation: General Principles and Advances.

Besides antiarrhythmic medication, there are now very good options for a potentially curative therapy by catheter ablation targeting the origin of the underlying arrhythmias in patients with complex congenital heart disease. Three-dimensional (3D) reconstruction of tomographic imaging (MRI or computed tomography) is helpful to understand the underlying cardiac anatomy, identify the most likely target chamber, and help with planning access. Use of the available 3D mapping systems (sequential or simultaneous acquisition) and (if available) more advanced navigation systems, such as remote magnetic navigation, can improve the acute and long-term outcomes of catheter ablation in congenital heart disease.

MAGNETIC VT study: a prospective, multicenter, post-market randomized controlled trial comparing VT ablation outcomes using remote magnetic navigation-guided substrate mapping and ablation versus manual approach in a low LVEF population.

Patients with ischemic cardiomyopathy (ICM) are prone to scar-related ventricular tachycardia (VT). The success of VT ablation depends on accurate arrhythmogenic substrate localization, followed by optimal delivery of energy provided by constant electrode-tissue contact. Current manual and remote magnetic navigation (RMN)-guided ablation strategies aim to identify a reentry circuit and to target a critical isthmus through activation and entrainment mapping during ongoing tachycardia. The MAGNETIC VT trial will assess if VT ablation using the Niobe™ ES magnetic navigation system results in superior outcomes compared to a manual approach in subjects with ischemic scar VT and low ejection fraction. This is a randomized, single-blind, prospective, multicenter post-market study. A total of 386 subjects (193 per group) will be enrolled and randomized 1:1 between treatment with the Niobe ES system and treatment via a manual procedure at up to 20 sites. The study population will consist of patients with ischemic cardiomyopathy with left ventricular ejection fraction (LVEF) of ≤35% and implantable cardioverter defibrillator (ICD) who have sustained monomorphic VT. The primary study endpoint is freedom from any recurrence of VT through 12months. The secondary endpoints are acute success; freedom from any VT at 1year in a large-scar subpopulation; procedure-related major adverse events; and mortality rate through 12-month follow-up. Follow-up will consist of visits at 3, 6, 9, and 12months, all of which will include ICD interrogation. The MAGNETIC VT trial will help determine whether substrate-based ablation of VT with RMN has clinical advantages over manual catheter manipulation. Clinicaltrials.gov identifier: NCT02637947.

Remote Magnetic versus Manual Navigation for Radiofrequency Ablation of Paroxysmal Atrial Fibrillation: Long-Term, Controlled Data in a Large Cohort.

Purpose. We aimed to study long-term outcome after pulmonary vein isolation (PVI) guided by remote magnetic navigation (RMN) and provided comparative data to outcome after manual navigation (MAN). Methods. Three hundred thirty-six patients with symptomatic paroxysmal AF underwent PVI by irrigated point-by-point radiofrequency (RF) ablation (RMN, n = 114 versus MAN, n = 222). Patients were followed up with symptom guided rhythm monitoring for a period up to 43 months. The end point of the study was freedom from repeat ablation after a single procedure and without antiarrhythmic drug treatment (ADT). Results. At the end of follow-up (median 26.3 months), freedom from repeat ablation was comparable between RMN and MAN (70.9% versus 69.5%, p = 0.61). At repeat, mean number of reconnected veins was 2.4 ± 1.2 in RMN versus 2.6 ± 1.0 in MAN (p = 0.08). The majority of repeat procedures occurred during the first year (82.1% in RMN versus 78.5% in MAN; p = 0.74). Conclusion. On the long term (up to 3 years) and in a large cohort of patients with paroxysmal AF, RMN-guided PVI is as effective as MAN guided PVI. In both strategies the majority of repeat procedures occurred during the first year after index procedure.

Early and Long-Term Outcomes After Manual and Remote Magnetic Navigation Guided Ventricular Tachycardia Ablation

Early and Long-Term Outcomes After Manual and Remote Magnetic Navigation Guided Ventricular Tachycardia Ablation

How to survive as a woman in a man's world.

Women in cardiology have to fight hard but can do it in style says Sabine Ernst ![Graphic][1] Gender never featured in the decisions of Dr Sabine Ernst, a cardiac electrophysiologist with expertise in complex arrhythmias. Today she is a consultant cardiologist and lead for electrophysiology (EP) research at the Royal Brompton and Harefield NHS Foundation Trust in London, UK, and a Reader at Imperial College London. But having found herself in what is still largely a man’s world, she has had to fight harder for promotion and still finds herself progressing more slowly than male colleagues. ‘In my academic career, if I had waited for someone to invite me to do something, I would still be waiting,’ says Ernst. During her training in EP Ernst initially received good support and mentoring from her chief in Hamburg, Professor Karl-Heinz Kuck. ‘We worked well together and I truly enjoyed the experience’, recalls Ernst. ‘This continued up to a point where I had achieved a certain level and then I had to fight for further promotion.’ Ernst was already doing the work of a consultant. She had performed first in man procedures, published extensively, ran an entire lab, had PhD students, and led the department’s educational courses. She had even pioneered remote magnetic navigation and used advanced 3D-mapping for patients with congenital heart disease, complex anatomy and arrhythmias. But she had not been promoted to any kind of leadership position and was not a consultant. ‘That was really tough because I had fought my way to the second highest academic title you can get in Germany at that stage but I still was … [1]: /embed/inline-graphic-1.gif

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.

Robotic magnetic navigation for ablation of human arrhythmias

Radiofrequency treatment represents the first choice of treatment for arrhythmias, in particular complex arrhythmias and especially atrial fibrillation, due to the greater benefit/risk ratio compared to antiarrhythmic drugs. However, complex arrhythmias such as atrial fibrillation require long procedures with additional risks such as X-ray exposure or serious complications such as tamponade. Given this context, the treatment of arrhythmias using robotic magnetic navigation entails a technique well suited to complex arrhythmias on account of its efficacy, reliability, significant reduction in X-ray exposure for both patient and operator, as well as a very low risk of perforation. As ongoing developments will likely improve results and procedure times, this technology will become one of the most modern technologies for treating arrhythmias. Based on the literature, this review summarizes the advantages and limitations of robotic magnetic navigation for ablation of human arrhythmias.

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