Remote Magnetic Navigation Research Articles

MoS2-based earth-like self-rotating and magnetically navigated nanorobots for magnetic resonance imaging, cancer cell imaging, and therapy

Microrobots are poised to revolutionize mass transport systems in emerging biomedical applications, yet their erratic motion poses a significant challenge in controlling their movements, particularly in-vivo. In this study, we introduce highly flexible, self-rotating nanorobots based on MoS2 Nanoflowers (NFs), offering superior control over their movement under magnetic field for cancer cell imaging and therapy. These nanorobots, termed MNBOTs, are constructed by embellishing pre-formed MoS2 NFs with NiFe2O3 nanoparticles (NPs) using polymeric linkers, capitalizing on the abundance of disulfide bonds on the MoS2 surface. In-vitro experiments showcased MNBOT's precise control over velocity, trajectory, and curvature, adapting seamlessly to changes in magnetic flux density under electromagnetic navigation. Moreover, MNBOTs were able to release NiFe2O3 NPs successfully in the tumor environment, facilitated by the collapse of disulfide bonds in the presence of glutathione/dithiothreitol, thus ensuring MNBOT's retrieval post-cancer therapy. Furthermore, we leveraged the photo-heat generation and paramagnetic features of MNBOTs for chemo-photothermal therapy (PTT) and magnetic resonance imaging (MRI) in ex vivo clinical settings. The combined effect of chemotherapy-PTT demonstrated remarkable cytotoxicity against MDA-MB-231 cancer cells, highlighting the synergistic potential of MNBOTs. The integration of diverse functionalities within MNBOTs, including remote magnetic navigation, photothermal therapy, and MRI, presents a versatile platform for addressing pressing healthcare needs, thus holding immense potential for future therapeutic and diagnostic applications.

Teleoperated Magnetic Endoscopy: A Case Study and Perspective

Teleoperated robotic surgery is a rapidly growing field that promises to overcome geographical barriers and share expertise over long distances for a variety of minimally invasive procedures. A particularly promising technology for teleoperation is robotic magnetic navigation. In contrast to conventional surgical robots, a robotic magnetic navigation system generates external magnetic fields to safely and dexterously steer soft magnetic devices within the human body, enabling a versatile, economical, and accessible telesurgery platform for a variety of procedures. This perspective highlights the recent research efforts in robotic magnetic platforms for telesurgery and their translation to clinical settings in the context of endoscopic procedures. This discussion is supported by a case study performed at the Multi‐Scale Medical Robotics Center in Hong Kong, where an in vivo gastroscopy in a porcine model is performed in tandem with two operators, alternating between a clinician controlling the procedure from the operating room in Hong Kong and a remote expert controlling the procedure from an operator console in Zurich. The achievements and challenges of this study highlight the capabilities and future potential of robotic magnetic navigation for telesurgery.

Remote magnetic navigation for catheter ablation of complex arrhythmias in congenital heart disease: an initial experience using a transnational telerobotic approach

Abstract Background The field of congenital electrophysiology (EP) is still in its relative infacncy with a limited number of electrophysiologists capable of performing catheter ablation in patients with congenital heart disease (CHD). As a result, patients or physicians are often required to travel great distances to performed specialised ablation procedures, something made near impossible during the COVID-19 pandemic. Objective We aimed to explore the feasibility and safety of a telerobotic approach to catheter ablation where the remote operator was situated approximately 1200km away from the patient and local team. Methods A 3D-printed 'phantom' heart was used in a pilot experiment in which no significant difference was seen between the local and remote operators in electroanatomic (EAM) mapping of the phantom heart using remote magnetic navigation (RMN). Catheter ablation was subsequently performed in patients with severe CHD using a transnational telerobotic approach to catheter ablation where the remote operator was able to view the dedicated console with live fluoroscopy, EAM and EP signals, as well as control the mapping and ablation catheters from 1200km away. As a safety precaution, radiofrequency (RF) could only be delivered by the local team. Results In total, 10 procedures were performed in 9 patients with severe CHD (mean age 38) between April and December 2021. All patients underwent an atrial ablation and one additional non-CHD patient underwent denervation of the pulmonary arteries. Median procedure duration was 335 (minutes) (IWR 230-349) with 11.5 minutes (QRS 3-15.4) of fluoroscopy exposure and 752 (IQR 674-905) seconds of RF delivery. There were no acute procedural complications. At one-year follow-up, one patient died as a result of heart failure and there were two arrhythmia recurrences. Conclusions Telerobotic catheter ablation is feasible and effective and creates the possibility of exciting new approaches to remote ablation and its use in the tele-proctoring of international fellows.

Electrocardiographic imaging to guide ablation of ventricular arrhythmias shows a higher benefit in patients with low intraprocedural burden

Abstract Background and aims Electrocardiographic imaging (ECGI) provides a non-invasive activation map of focal ventricular arrhythmias that has shown good accuracy regardless of the type of cardiac source used. Pre-procedure diagnosis in cases that are expected to be difficult and management of infrequent or poorly tolerated or multiple arrhythmias are some situations that may benefit the most from having an ECGI performed before the procedure. This study aimed to assess the benefit of the ECGI in patients with low intraprocedural burden. Methods We performed 81 ECGI procedures in 64 consecutive patients referred for ablation of ventricular arrhythmias (VAs). Ablations were performed with remote magnetic navigation or manually. The localization of the VAs based on the ECGI and invasive electroanatomic mapping was performed using a segmental model of the ventricles. A perfect match (PM) was defined as a predicted location within the same anatomic segment, whereas a near match (NM) was defined as a predicted location within the same segment or a contiguous one. The agreement between the ECGI and the invasive map was evaluated. The benefit of the ECGI in the subgroup of patients with intraprocedural infrequent VAs, defined as less than 1 VA complex /min, was assessed in terms of the success of the procedure. Results The ECGI was performed with the AMYCARD 01 only, in 26 patients, with the VIVO only, in 21 patients, and with both systems in 17 patients. Fifty-one patients underwent ablation. 65 ECGI procedures were performed before ablation in those 51 patients, 37 with Amycard with a rate of PM of 79% and NM of 97%, and 28 ECGI procedures with VIVO with 82% of PM and 93% of NM, not significantly different, respectively, p=0.764 and 0.573. The overall success rate was 80%. The low intraprocedural burden group included 28 patients (2 examples shown in the figure). The success rate was 86%, higher than the overall success rate, and much higher than the previously reported in the literature for this group of patients. Conclusions The ECGI was useful in predicting the location of the VA in general but was especially helpful in cases that are usually challenging, like patients with intraprocedural infrequent VAs.

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.

Best practices in robotic magnetic navigation-guided catheter ablation of cardiac arrhythmias, a position paper of the Society for Cardiac Robotic Navigation.

Robotic magnetic navigation (RMN)-guided catheter ablation (CA) technology has been used for the treatment of cardiac arrhythmias for almost 20 years. Various studies reported that RMN allows for high catheter stability, improved lesion formation and a superior safety profile. So far, no guidelines or recommendations on RMN-guided CA have been published. The aim of this consensus paper was to summarize knowledge and provide recommendations on management of arrhythmias using RMN-guided CA as treatment of atrial fibrillation (AF) and ventricular arrhythmias (VA). An expert writing group, performed a detailed review of available literature, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Recommendations on RMN-guided CA are presented in a guideline format with three levels of recommendations to serve as a reference for best practices in RMN procedures. Each recommendation is accompanied by supportive text and references. The various sections cover the practical spectrum from system and patient set-up, EP laboratory staffing, combination of RMN with fluoroscopy and mapping systems, use of automation features and ablation settings and targets, for different cardiac arrhythmias. This manuscript, presenting the combined experience of expert robotic users and knowledge from the available literature, offers a unique resource for providers interested in the use of RMN in the treatment of cardiac arrhythmias.

Remote magnetic navigation catheter ablation for atrial tachycardia in a patient with d-transposition of the great arteries, atrial switch, and a mechanical valve in the tricuspid position.

Remote magnetic navigation catheter ablation for atrial tachycardia in a patient with d-transposition of the great arteries, atrial switch, and a mechanical valve in the tricuspid position.

Intelligent electromagnetic navigation system for robot-assisted intraoral osteotomy in mandibular tumor resection: a model experiment.

Mandibular tumor surgery necessitates precise osteotomies based on tumor boundaries; however, conventional osteotomies often lack accuracy in predicting osteotomy positions and planes, potentially leading to excessive resection of normal bone tissues or residual tumors, thus compromising postoperative quality of life and clinical outcomes. Robotic-assisted surgery (RAS) augmented with artificial intelligence (AI) offers precise localization capabilities, aiding surgeons in achieving accurate osteotomy positioning. This study aimed to evaluate the feasibility and accuracy of a robotic magnetic navigation system for positioning and osteotomy in an intraoral surgical trial of a mandibular tumor model. Patient computed tomography (CT) imaging data of mandibular chin and body tumors were utilized to create 3D printed models, serving as study subjects for mandibular tumor resection. Ten pairs of models were printed for the experimental and control groups. The experimental group (EG) underwent osteotomy using a robot-assisted surgical navigation system, performing osteotomy under robotic navigation following alignment based on preoperative design. The control group (CG) underwent traditional surgery, estimating osteotomy position empirically according to preoperative design. Postoperative CT scans were conducted on both models, and actual postoperative results were compared to preoperative design. Osteotomy accuracy was evaluated by positional and angular errors between preoperatively designed and actual osteotomy planes. For ten randomly selected spots on the left and right sides, respectively, the EG group had mean distance errors of 0.338mm and 0.941mm. These values were obtained from the EG group. In the EG group, on the left side, the mean angular errors were 14.741 degrees, while on the right side, they were 13.021 degrees. For the 10 randomly selected spots on the left and right sides, respectively, the CG had mean distance errors of 1.776mm and 2.320mm. This is in contrast to the results obtained by the EG. It was determined that the left side had a mean angle error of 16.841 degrees, while the right side had an error of 18.416 degrees in the CG group. The above results indicated significantly lower point errors of bilateral osteotomy planes in the experimental group compared to the control group. This study demonstrates the feasibility of electromagnetic navigation robot-assisted intraoral osteotomy for mandibular tumors and suggests that this approach can enhance the precision of clinical surgery.

Retrograde access of the left atrium for catheter ablation in atrial fibrillation using robotic magnetic navigation: A case series

Retrograde access of the left atrium for catheter ablation in atrial fibrillation using robotic magnetic navigation: A case series

Different electrophysiological characteristics of cavo-tricuspid isthmus dependent atrial flutter guided by robotic magnetic navigation in patients with and without prior cardiac surgery.

Cavo- tricuspid isthmus dependent atrial flutter (CTI- AFL) is a common atrial arrhythmia in patients with prior cardiac surgery (postsurgical AFL) and without prior cardiac surgery (nonsurgical AFL). However, there is only limited data regarding the eletrophysiological differences between the CTI- AFL in the postsurgical patients and the nonsurgical patients. We aimed to investigate the differences in clinical and electrophysiological characteristics between the postsurgical group and nonsurgical group and to evaluate the acute and long-term outcomes after ablation guided by robotic magnetic navigation (RMN) in both the groups. Methods Fourty-two consecutive patients with nonsurgical AFL and 21 with postsurgical AFL were retrospectively analyzed in our center. Electrocardiographic (ECG) analysis and three-dimensional electrophysiological study were performed in all the patients. The results revealed that only 55.6% of postsurgical patients with proven counterclockwise (CCW) AFL presented with a typical ECG suggesting this mechanism. In contrast, 86.1% of nonsurgical patients demonstrated a typical ECG pattern for CCW AFL. In addition, we employed a reverse "U-curve" to facilitate radiofrequency delivery when ablating near the inferior vena cava ostium in the present study. Compared with the nonsurgical group, electroanatomical mapping showed the mean AFL cycle length was significantly longer (253.3 ± 40.4 vs. 234.1 ± 24.2 ms, p = 0.03) and the right atrium volume was larger (114.8 ± 26.0 vs. 97.5 ± 19.1 mL, p = 0.004) in the postsurgical group. Additionally, the procedural time (75.9 ± 21.3 vs. 61.6 ± 26.6 minutes, p = 0.03) and ablation time (53.0 ± 21.4 vs. 36.7 ± 25.6 minutes, p = 0.02) are much longer in the postsurgical group. However, the navigation index in the postsurgical group was significantly smaller (0.35 ± 0.08 vs. 0.43 ± 0.13, p = 0.01). Moreover, the acute and long-term success rates were comparable between the two groups. Catheter ablation of CTI-AFL with and without prior cardiac surgery guided by RMN are associated with high acute and long-term success rates, despite the procedural and ablation times are much longer in the postsurgical patients. However, ECG characteristics of the tachycardia may be misleading as they are more often atypical in patients after cardiac surgery.

Retrograde access of the left atrium for catheter ablation using robotic magnetic navigation in atrial fibrillation: a case series

Abstract Funding Acknowledgements Type of funding sources: None. Background Pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) ablation for which the left atrium (LA) is usually accessed by the antegrade femoral venous route and transseptal puncture. However, in rare cases, alternative routes must be used to overcome anatomical challenges. A retrograde approach via the femoral artery and by subsequently passing the aortic and mitral valve is virtually impossible using conventional catheters. Purpose To investigate the feasibility of a retrograde approach for AF ablation by robotic magnetic navigation (RMN) using floppy radiofrequency ablation catheters. Methods Between June 2014 and December 2021, a total of 6 consecutive patients underwent a total of 8 ablation procedures for AF by retrograde approach using a RMN at tour center. A magnetic catheter was introduced through the right femoral artery and manually advanced retrogradely to the aortic arch. Thereafter, it was further advanced to the LA using RMN by switching the magnets to navigation mode, passing through both aortic and mitral valve (Figure 1). Circumferential PVI was performed by antral point-by-point radiofrequency ablation and additional atrial lines were targeted when deemed necessary. Bidirectional conduction block was proven by loss of pulmonary vein potentials on the ablation catheter which automatically moved in a radial manner collecting 16 mapping points. Results The patient group (Figure 2) consisted of 4 females and 2 males with a mean age of 58,0±10,8years. 4 patients (67%) presented with persistent AF. The mean time between diagnosis and catheter ablation was 5,3±3,5 years. 2 patients (33%) had an acquired mechanical obstruction of the conventional transseptal route. The other 4 patients (67%) had an anatomical abnormality precluding conventional access to the LA. These 4 patients all underwent an unsuccessful ablation attempt via conventional approach elsewhere, before referral to our center. Patients 3 and 4 also underwent an epicardial ablation for AF respectively 1,3 and 6,2 years before catheter ablation using RMN. Patient 3 also underwent a failed attempt on manual catheter ablation using the retrograde route in another center. AF catheter ablation via retrograde access using RMN was possible in all patients and no complications occurred. The mean follow-up was 3,4±3,3 years. Conclusion Our findings indicate that a retrograde transaortic approach for catheter ablation in AF using magnetic navigation system and electroanatomical mapping is technically feasible and safe in patients with anatomical challenges precluding the use of a conventional antegrade transseptal approach. This technique may serve as an indispensable component of the management of this subgroup of patients in experienced centers.

Bipolar ablation: first in man using combined robotic magnetic navigation with a manual approach in a complex pvc case

Abstract Funding Acknowledgements Type of funding sources: None. Background Standard unipolar catheter ablation (UPA) with radiofrequency for ventricular arrhythmias has reportedly recurrence rates due to a lack of efficient lesions in the deep myocardial substrates to disrupt the critical components of the arrhythmia circuit. First in-vivo bipolar catheter ablations (BPA) show promising results to counter this issue. Precise handling of two catheters simultaneously during BPA is a challenge that the utilization of a robotic magnetic navigation (RMN) system could make safer by robotically controlling one of the catheters. Method A RMN ablation catheter with a 3.5 mm irrigated tip (RMN Navistar Thermocool, Biosense Webster), as an active catheter, as well as an indifferent manual catheter 3.5 mm irrigated non-nav ablation catheter (Celsius Thermocool, Biosense Webster) was connected to a BPA-certified generator system (HAT 500® system (OSYPKA, Germany)). The RMN catheter was controlled by a RMN Stereotaxis- system. A 3D Carto system combined with a VIVO system was used to find the right localization. Results 70-year-old male with ischemic CMP, EF nearly 40%, revascularized through CABG, presented after 4 attempts of ablation of very frequent symptomatic monomorphic PVCs (more than 30000 /24h), with different approaches in different hospitals. The origin of PVCs was mid-septal RV/LV. After LAT Mapping in a transseptal approach with the RMN Catheter (LV), the manual catheter was placed at the opposite site in the RV. Bipolar Ablation was done at 30W (3 min) with acute suppression of the PVCs. The follow-up duration was 6-months with still lasting good result. No complications occurred. Conclusions BPA ablation is an additional energy option in difficult cases. With a RMN system is it feasible and safe. The robotic control of one of the two ablation catheters provides a precise and stable execution of the BPA since the operator only needs to control the second catheter manually while the magnetic field holds the first in place. It therefore also allows a single operator approach.

Non-invasive electrocardiographic ventricular mapping based on the equivalent double layer model: different workflows, same accuracy

Abstract Funding Acknowledgements Type of funding sources: None. Background and aim Electrocardiographic imaging (ECGI) is capable of performing activation maps with a single premature beat. The endo-epicardial ECGI system based on the equivalent double layer model (EDL), is a portable system that uses a patient-specific heart torso geometry obtained from a CT-scan or cardiac magnetic resonance (CMR), and a conventional 12-lead ECG. The simplicity of the system allows for its use either as a pre-procedural or intra-procedural tool. The aim of this study was to assess the accuracy of the system in centres using different workflows. Methods We studied consecutive patients referred for ablation of ventricular arrhythmias that had an ECGI performed with the endo-epicardial system based on the EDL model to guide mapping and catheter ablation, at four centres. Three centres performed the ECGI pre-procedurally, two with the use of a bedside portable ECG recorder and one on ambulatory basis with a 12-lead Holter recorder, and ablation was performed either manually or with remote magnetic navigation (RMN). The fourth centre performed the ECGI intra-procedurally, recording the ECG directly from the electrophysiology digital multichannel system, and the ablation was performed manually with the use of intracardiac echo (ICE) in all cases. VAs were localised using a segmental model, which included 22 left ventricular segments (classical 17-segment model, plus the aortic cusps and the papillary muscles), and 12 segments on the right ventricle including 4 on the right ventricular outflow tract (RVOT): Anterior, lateral, right septum and left septum. A perfect match (PM) was defined as a predicted location within the same anatomic segment, whereas a near match (NM) was defined as a predicted location within the same segment or a contiguous one. We studied the three different workflows. Results Sixty-three arrhythmias were studied in 58 patients. The ECGI was performed pre-procedurally with a bedside ECG recorder in 26 cases, pre-procedurally with a Holter recorder in 27 cases and intra-procedurally in 10 cases. The results according to each group are presented in the Table. The accuracy of the ECGI was not different between groups. The system correctly identified the SOO of the VAs in the same or a contiguous segment when compared to the invasive mapping in all patients, regardless of the approach used. The percentage of PM was also not significantly different. The group with ICE guidance had lower fluoroscopy and mapping times, but the success and recurrence rates were similar. Conclusions The results of this multicentre experience show that this ECGI system, using a conventional 12 -lead ECG is simple and accurate across different clinical workflows, and presents a useful and versatile tool to facilitate planning the ablation strategy as well as intra-procedural guidance for mapping and ablation of patients with VAs.

Non-invasive electrocardiographic mapping using an endo-epicardial system based on extracellular potentials shows better accuracy for atrial arrhythmias than ventricular arrhythmias

Abstract Funding Acknowledgements Type of funding sources: Private hospital(s). Main funding source(s): Learning Health Background and aim Electrocardiographic imaging (ECGI) is capable of performing an activation map with a single beat. The endo-epicardial system based on extracellular potentials allows for the reconstruction of endo-epicardial potentials both in the ventricles and the atria. The aim of this study was to compare the accuracy of the system to predict the site of origin (SOO) of ventricular focal arrhythmias (VAs) versus atrial focal arrhythmias (AAs). Methods We studied 55 consecutive patients referred for ablation of VAs or AAs that had an ECGI performed before ablation. Ablations were performed with remote magnetic navigation or manually. The localization of the VAs and AAs based on the ECGI and invasive electroanatomic mapping was performed using a segmental model of the atria and the ventricles. A perfect match (PM) was defined as a predicted location within the same anatomic segment, whereas a near match (NM) as a predicted location within the same segment or a contiguous one. The number of leads used for ECGI mapping, the agreement between the ECGI and the invasive map, and the success of the procedure were evaluated. Results Ablation was performed in 49 patients. We mapped 54 arrhythmias, 37 VAs (37 patients) and 17 AAs (12 patients). The results according to the atrial or ventricular origin of the arrhythmia are depicted in the table. Patients with AAs were older, no other differences were significant. The ECGI system correctly identified the SOO of both VAs and AAs in the same segment or a contiguous one in 100% of AAs and 97% of VAs, p=1.000. However, the percentage of a PM (Figure) was higher for AAs than for VAs (100% vs 76%, p=0.044). Conclusions The endo-epicardial ECGI correctly identified the origin of both ventricular and atrial arrhythmias. However, the accuracy was higher for the latter.

Robotic magnetic navigation guided catheter ablation establishes highly effective pulmonary vein isolation in patients with paroxysmal atrial fibrillation, when compared to conventional techniques

Abstract Funding Acknowledgements Type of funding sources: None. Background Catheter ablation (CA) is an important treatment option for patients with atrial fibrillation (AF). Pulmonary vein isolation (PVI) is a pivotal part of any AF ablative therapy. Currently, there are multiple techniques available to realize PVI, including: manual guided cryoballoon (MAN-CB), manual guided radiofrequency (MAN-RF) and Remote Magnetic Navigation guided RF ablation (RMN-RF). However, there is lack of large prospective trials comparing contemporary RMN-RF with the conventional CA techniques. Purpose This study prospectively analyzed and compared three catheter ablation techniques in patients with paroxysmal AF. Methods This multicenter, prospective study included patients with paroxysmal AF who underwent their first CA procedure with one of the mentioned ablation techniques. Procedural parameters (including procedural efficiency), complication rates and freedom of AF during 12-month follow-up were compared between three study groups defined by the utilized ablation technique. Results A total of 221 patients were included in this study. Total procedure time was significantly shorter in MAN-CB (78±21 min) compared to MAN-RF (115±41 min) and compared to RMN-RF (129±32 min) (P&amp;lt;0.001), whereas it was comparable between the two RF groups. A 3% complication rate was observed which was comparable between all groups. At 12-month follow-up, we observed AF recurrence in 40 patients (19%). AF recurrence was significantly lower in the RMN-RF group (MAN-CB 19 (24%) AF recurrences, MAN-RF 16 (23%), RMN-RF 5 (8%), P=0.045; multivariate HR of RMN-RF on AF recurrence 0.32, 95%-CI 0,12–0.87, P=0.026; with MAN-CB + MAN-RF as the reference group). Conclusion RMN guided PVI results in high freedom of AF in patients with paroxysmal AF, when compared to cryoablation and manual RF ablation. Cryoablation remains the most time efficient ablation technique, whereas RMN has comparable efficiency with manual RF ablation.

Robotic magnetic navigation-guided pulmonary vein isolation in an atrial fibrillation patient with dextrocardia situs inversus: techniques and potential advantages

BackgroundDextrocardia with situs inversus (DSI) is a very rare congenital anomaly. Catheter manipulation and ablation of atrial fibrillation (AF) in patients with this anatomical variant is challenging for the operators. This case report presents a safe and effective AF ablation guided by the robotic magnetic navigation (RMN) system in combination with intracardiac echocardiograhy (ICE) in a patient with DSI.Case presentationA 64-year-old male with DSI was referred for catheter ablation of symptomatic, drug-refractory paroxysmal AF. One transseptal access was achieved via the left femoral vein under the guidance of ICE. The three-dimensional reconstruction of the left atrium and the pulmonary veins (PVs) were performed by the magnetic catheter using the CARTO and the RMN system. Then, the electroanatomic map and pre-acquired CT images were merged. Finally, bilateral circumferential ablation lines were delivered around the ipsilateral PV ostia to achieve complete PV isolation (PVI).ConclusionsThis case demonstrates that AF catheter ablation under the guidance of the RMN system using ICE is feasible and safe in a patient with DSI. Moreover, the combination of these technologies broadly facilitates treatment of patients with complex anatomy, while reducing the risk of complications.

The performance of dipole charge density mapping integrated with robotic magnetic navigation in the treatment of atrial tachycardias

BackgroundCatheter ablation (CA) has become a well-established first-line therapy for a broad spectrum of arrhythmias, including atrial tachycardias (ATs). In this study we aimed to assess the performance of the integrated novel high-resolution new generation noncontact mapping system (AcQMap) with robotic magnetic navigation (RMN) system in CA procedures for patients with ATs including comparing patient subgroups based on the utilized mapping modality, arrhythmia mechanism, localization and type of procedure.MethodsAll patients undergoing CA for AT using the AcQMap-RMN system were included. Procedural safety and efficacy were characterized by intra- and post-procedural complications. Acute procedural success and the long-term outcome were assessed in the overall group and in the subgroups.ResultsA total number of 70 patients were referred for CA with atrial arrhythmias including 67 AT/AFL (mean age 57.1 ± 14.4 years), and 3 additional patients with inappropriate sinus tachycardia. Thirty-eight patients had de novo AT, 24 had post-PVI AT including 2 patients with perinodal AT, and 5 had post-MAZE AT. Two patients (2.9%) suffered post-procedural complications including 1 patient with groin hematoma and 1 patient with a transient ischemic attack. Acute success was achieved in 63/67 (94.0%) procedures. Thirteen patients (19.4%) had documented recurrence at the end of the 12-months follow-up period. The performance of AcQMap was equally good in focal vs. reentry mechanisms (p = 0.61, acute success), in the left and right atrium (p = 0.21).ConclusionsAcQMap-RMN integration might improve success rates in CA of ATs with low number of complications.

Radiofrequency ablation of premature ventricular contractions guided by robotic magnetic navigation combined with pattern matching filter

This study's intent is to evaluate the usefulness of pattern matching filter (PMF) function combined with robotic magnetic navigation (RMN) in guiding the ablation of premature ventricular contractions (PVCs). Assume that PMF can improve the outcomes of PVCs ablation using RMN. A retrospective analysis was completed consisting of 118 consecutive patients with PVCs who underwent radiofrequency ablation guided by RMN. According to the application of PMF, patients were divided into two groups: 20 patients underwent ablation without PMF (group A), and another 98 patients received ablation incorporating PMF (group B). Compared with group A, the procedure time (135.0 ± 28.3 min vs. 106.3 ± 37.9 min, p = 0.02) in group B was significantly decreased, while the X-ray exposure time (6.0 ± 2.6 min vs. 6.5 ± 3.6 min, p = 0.705) and dose (3.2 ± 2.4 gycm2 vs. 3.9 ± 2.7 gycm2 ，p = 0.208) had no significant difference. Group B had a more than twofold number of points acquired (66.9 ± 23.0 vs. 143.9 ± 68.3, p < 0.001) and required a shorter radiofrequency ablation time (13.2 ± 3.5 min vs. 8.1 ± 2.9 min, p < 0.001). There were no serious complications in either group. The acute success rate was similar [90.0% (18/20) vs. 87.8% (86/98), p = 1.000] in two groups, and the success rate was also similar in the long-term follow-up [83.3% (15/18) vs. 87.2% (75/86), p = 0.776]. The ablation of PVCs guided by RMN is safe and effective. Combined with the functional capability of PMF, both procedure time and radiofrequency ablation time were significantly decreased.

Robotic magnetic-guided catheter ablation in patients with congenital heart disease: a systematic review and pooled analysis

ABSTRACT Background Robotic magnetic navigation (RMN) has emerged as a potential solution to overcome challenges associated with catheter ablation of arrhythmias in patients with congenital heart disease (CHD). Objectives To assess safety and efficacy of RMNguided catheter ablation in patients with CHD. Design and Methods A systematic review and pooled analysis was conducted on patients with CHD who underwent RMNguided catheter ablation. Random effects models were used to generate pooled estimates with the inverse variance method used for weighting studies. Results Twentyfour nonoverlapping records included 167 patients with CHD, mean age 36.5 years, 44.6% female. Type of CHD was simple in 27 (16.2%), moderate in 32 (19.2%), and complex in 106 (63.5%). A total of 202 procedures targeted 260 arrhythmias, the most common being macroreentrant atrial circuits. The mean procedural duration was 207.5 minutes, with a mean fluoroscopy time of 12.1 minutes. The pooled acute success rate was 89.2% [95% CI (77.8%, 97.4%)]. Freedom from arrhythmia recurrence was 84.5% [95% CI (72.5%, 94.0%)] over a mean follow-up of 24.3 months. The procedural complication rate was 3.5% with no complication attributable to RMN technology. Conclusion RMN-guided ablation appears to be safe and effective across a variety of arrhythmia substrates and types of CHD.

Gradiometer-Based Magnetic Localization for Medical Tools

Remote magnetic navigation (RMN) offers various possibilities for medical interventions. Magnetic catheters can be wirelessly steered with high precision and accuracy through complex structures, as they are generally more dexterous and flexible than their manually steered counterparts. Position feedback is essential for many tasks. However, most of the commercially available systems do not integrate well with the magnetic navigation systems (MNSs). As a result, fluoroscopy is still widely used in many interventions despite the known associated health risks. In this study, we propose a localization method that uses multiple Hall sensors to measure the magnetic fields produced by the MNS and estimate the full sensor pose without the need for a separate dedicated mapping system. This makes the MNS a two-in-one system that can be used for simultaneous navigation and localization of a medical tool. We perform an optimization of the sensors’ array design in simulation and investigate the influence of the magnetic fields and gradients on the localization accuracy to provide information on the minimal requirements for an MNS for this task.