Remote magnetic navigation in atrial fibrillation

Atrial Fibrillation Ablation in Congenital Heart Disease: Therapeutic Challenges and Future Perspectives

The increasing prevalence of atrial fibrillation (AF) in adults with congenital heart disease raises significant questions regarding its management. The unique underlying anatomic and physiological background further adds to the difficulty in eliminating the AF burden in these patients. Herein, we provide an overview of the current knowledge on the pathophysiology and risk factors for AF in adult congenital heart disease, with a special focus on the existing challenges in AF ablation. Emerging imaging modalities and ablation techniques might have a role to play. Evidence regarding the safety and efficacy of AF ablation in adult congenital heart disease is summarized, especially for patients with an atrial septal defect, Ebstein anomaly of the tricuspid valve, tetralogy of Fallot, and Fontan circulation. Finally, any remaining gaps in knowledge and potential areas of future research are highlighted.

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

BACKGROUND

Catheter 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.

METHODS

All 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.

RESULTS

A 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).

CONCLUSIONS

AcQMap-RMN integration might improve success rates in CA of ATs with low number of complications.

Dipole charge density mapping integrated in remote magnetic navigation: First-in-human feasibility study

Aims

Robotic magnetic navigation (RMN) provides increased catheter precision and stability. Formerly, only the CARTO 3 mapping system was integrated with the RMN system (CARTO-RMN). Recently, a novel high-resolution non-contact mapping system (AcQMap) has been integrated with the RMN system (AcQMap-RMN) for the treatment of atrial fibrillation (AF) and atrial tachycardias (AT). We aim to compare the safety, efficiency, and efficacy of AcQMap-RMN with CARTO-RMN guided catheter ablation (CA) procedures.

Material and methods

In this prospective registry, procedural safety efficiency and outcome data from total of 238 consecutive patients (147 AcQMap-RMN and 91 CARTO-RMN patients) were compared.

Results

AcQMap-RMN is non-inferior in the primary endpoint of safety as compared to CARTO-RMN across the whole group (overall procedural complications in 5 (3.4%) vs. 3 (3.3%) patients, p = 1.0). Overall procedure durations were longer and associated with more fluoroscopy use with AcQMap-RMN (172.5 vs. 129.6 min, p < 0.01; 181.0 vs. 131.0 mGy, p = 0.02, respectively). Procedure duration and fluoroscopy use decreased significantly between the first 30 and the last 30 AcQMap-RMN procedures. The AcQMap-RMN system had fewer recurrences after persistent AF ablations and was non-inferior in paroxysmal AF patients compared to CARTO-RMN at 12 months (36.6% vs. 75.0%, p = 0.04, PAF 6.6% vs. 12.5%, p = 0.58; respectively). CA of AT outcomes were better using the AcQMap-RMN system (1 year recurrence 17.1% vs. 38.7%, p < 0.05).

Conclusion

AcQMap-RMN integration has no negative impact on the excellent safety profile of RMN guided ablations. It improves outcomes of CA procedures for persAF and AT but requires longer procedure times and higher fluoroscopy use during the initial learning phase.

Application of magnetic nanoparticles in cell therapy

Fe₃O₄ magnetic nanoparticles (MNPs) are biomedical materials that have been approved by the FDA. To date, MNPs have been developed rapidly in nanomedicine and are of great significance. Stem cells and secretory vesicles can be used for tissue regeneration and repair. In cell therapy, MNPs which interact with external magnetic field are introduced to achieve the purpose of cell directional enrichment, while MRI to monitor cell distribution and drug delivery. This paper reviews the size optimization, response in external magnetic field and biomedical application of MNPs in cell therapy and provides a comprehensive view.

Stabilizing interventional instruments in the cardiovascular system: A classification of mechanisms

Positioning and stabilizing a catheter at the required location inside a vessel or the heart is a complicated task in interventional cardiology. In this review we provide a structured classification of catheter stabilization mechanisms to systematically assess their challenges during cardiac interventions. Commercially available, patented, and experimental prototypes of catheters were classified with respect to their stabilizing mechanisms. Subsequently, the classification was used to define requirements for future cardiac catheters and persisting challenges in catheter stabilization. The classification showed that there are two main stabilization mechanisms: surface-based and volume-based. Surface-based mechanisms apply attachment through surface anchoring, while volume-based mechanisms make use of locking through shape or force against the vessel or cardiac wall. The classification provides insight into existing catheter stabilization mechanisms and can possibly be used as a tool for future design of catheter stabilization mechanisms to keep the catheter at a specific location during an intervention. Additionally, insight into the requirements and challenges for catheter stabilization inside the heart and vasculature can lead to the development of more dedicated systems in the future, allowing for intervention- and patient-specific instrument manipulation.

Remote magnetic navigation versus manual control navigation for atrial fibrillation ablation: A systematic review and meta-analysis

BACKGROUND

The aim of this review was to evaluate the efficacy and safety between remote magnetic navigation (RMN) and manual control navigation (MCN) for atrial fibrillation (AF) ablation.

METHODS

We searched the PubMed, EMBASE and Cochrane library databases using the key words AF, ablation and magnetic navigation.

RESULTS

Eighteen studies were identified in this analysis including 4046 patients comparing RMN and MCN in AF ablation, which were all non-randomized controlled studies. No significant difference of AF recurrence rate (40% vs. 38%, OR 1.00, 95% CI 0.82-1.22, p = 0. 97) and acute success rate in achieving pulmonary vein isolation (91% vs. 93%, OR 0.44, 95% CI 0.16-1.17, p = 0.10) was found between RMN and MCN. However, compared with MCN, RMN was associated with significantly lower complication rate (2% vs. 5%, OR 0.44, 95% CI 0.28-0.69, p = 0. 0003) and shorter fluoroscopy time (MD -9.71 min, 95% CI -15.80 to -3.63, p = 0.002). Procedure time (MD 47.05 min, 95% CI 27.5-66.58, p < 0.00001) and ablation time (MD 15.90 min, 95% CI 9.62-22.18, p < 0.00001) of RMN guided AF ablation were significantly longer than those of MCN.

CONCLUSION

The results of this study suggest that RMN is as effective as MCN in achieving pulmonary vein isolation and freedom from AF recurrence, and has superior safety with less complications and shorter fluoroscopy time.

Comparisons of efficacy, safety, and recurrence risk factors of paroxysmal and persistent atrial fibrillation catheter ablation using robotic magnetic navigation system

Background

No data exist on comparisons of efficacy, safety, and recurrence risk factors of paroxysmal and persistent atrial fibrillation (AF) ablation using robotic magnetic navigation system (MNS), respectively.

Methods

About 151 AF patients were prospectively enrolled and divided into paroxysmal AF group (n = 102) and persistent AF group (n = 49). Circumferential pulmonary vein antrum isolation (CPVI) was performed in all patients. Linear ablation at the left atrial roof and mitral isthmus was performed in patients with persistent AF in addition to CPVI. The procedural time, X‐ray exposure time, acute and long‐term success rates of CPVI, and procedure‐related complications were analyzed. The AF recurrence rates in the two groups were compared during 1 year, and Cox regression was used to analyze the recurrence risk factors.

Results

The acute success rates of CPVI in the two groups were 98.04% and 97.96%, respectively. There were no significant differences in the procedural time, X‐ray exposure time, and ablation time between the two groups (P > 0.05). No serious complications appeared in either group. The AF ablation success rates were 70.6% and 57.1% for the paroxysmal and persistent groups respectively at 12‐month follow‐up (P = 0.102). AF duration and coronary heart disease prior to ablation were associated with the higher AF recurrence in patients with persistent AF.

Conclusion

Ablation using MNS is effective and safe both in patients with paroxysmal and persistent AF. AF duration and coronary heart disease prior to ablation are two independent risk factors of AF recurrence in patients with persistent AF postoperatively.

The Use of Innovative Technologies to Guide Cardiac Procedures

The advantages of intracardiac echocardiography (ICE) include shorter procedure times, reduced radiation exposure and the elimination of the need for general anesthesia. It is also effective in the safe performance of transseptal punctures. These have led to its increasing use in electrophysiology (EP) procedures. The use of ICE provides unrestricted access to the cardiac anatomy and guides interventional cardiac procedures by providing high-quality images of intracardiac structures and devices. As well as their use as imaging in catheter ablation of atrial fibrillation and other arrhythmias, ICE ultrasound catheters may be used in cardiac valve repair and the closure of atrial septal defects (ASDs). Integration of ICE catheters with electroanatomical mapping systems that construct three dimensional (3D) images have further increased the application of the technique. The use of magnetic navigation systems (MNS) have conferred further advantages including reduced exposure to fluoroscopy and increased operator comfort. This article presents four clinical cases and reviews clinical studies of these techniques.

Feasibility of remote magnetic navigation for epicardial ablation

Percutaneous epicardial mapping and ablation is an emerging method to treat ventricular tachycardias (VT), premature ventricular complexes (PVC), and accessory pathways. The use of a remote magnetic navigation system (MNS) could enhance precision and maintain safety. This multiple case history demonstrates the feasibility and safety of the MNS-guided epicardial approach in mapping and ablation of ischaemic VT, outflow tract PVCs, and a left-sided accessory pathway. All patients had previously undergone endocardial mapping for the same arrhythmia. MNS could present an advantage from more precise navigation for mapping and maintaining catheter stability during energy application.