ClinicalAblationEndo-epicardial ablation of ventricular arrhythmias in the left ventricle with the Remote Magnetic Navigation System and the 3.5-mm open irrigated magnetic catheter: Results from a large single-center case–control series
Introduction
Radiofrequency catheter ablation (RFCA) is an important option for controlling recurrent ventricular arrhythmias (VAs).1, 2, 3 The field has evolved rapidly due to introduction of new technologies, improved understanding of arrhythmia mechanisms, and improved procedural safety and patient outcomes. However, results are often operator dependent and difficult to replicate. Remote magnetic navigation (RMN) and ablation is a new technology that offers the possibility to reduce the operator dependency and improve catheter stability while minimizing the physician's exposure to radiation. Clinical studies have consistently reported that RMN may represent a new and safe strategy to successfully ablate both supraventricular and ventricular arrhythmias.4, 5, 6, 7, 8, 9, 10
To date, the major drawback of RMN is the unavailability of a magnetic open-irrigated-tip catheter (OIC), thus limiting RF power to be maintained in a desirable range in areas of low local blood flow, such as dilated and poorly contracting ventricles.11, 12, 13 For this reason, operators may frequently need to switch to manual ablation to improve the transmurality and efficacy of the lesions. This represents a significant limitation for ablation of VAs, especially in the presence of a structural heart disease, because of the relatively larger size of responsible re-entrant circuits and the fact that they can be located deep to the endocardium. Accordingly, ablation through nonirrigated catheters in this clinical setting often fails to achieve adequate ablation of lesions.14, 15
The purpose of this study was to evaluate the safety and efficacy of RFCA using the RMN system with the magnetic OIC ablation catheter in a large series of patients with VAs.
Section snippets
Methods
One hundred and ten consecutive patients with clinical and symptomatic VAs underwent RFCA with the remote magnetic navigation (Stereotaxis, St. Louis, Missouri) and the magnetic OIC between March 2009 and November 2009.
The 7-F 3.5-mm-tip floppy irrigated catheter (Navistar Thermocool RMT, Biosense Webster, Diamond Bar, California) became available in the United States in March 2009 to overcome the limitations of the previous 4-mm and 8-mm nonirrigated magnetic catheter. All Remote Magnetic
Patient characteristics
The clinical characteristics and electrophysiologic features of the 110 patients undergoing RFCA with the RMN system are reported in Table 1. The mean LV ejection fraction was 40% ± 14%. All patients included in this study had previously failed treatment with 2 ± 0.9 antiarrhythmic drugs (AADs). Twenty-six (24%) patients presented with the clinical morphology of sustained VT, and 84 (76%) patients had frequent PVCs. Forty-five (41%) patients had an implantable cardioverter-defibrillator (ICD)
Major findings
This is the largest series of consecutive patients undergoing catheter ablation of VAs and PVCs with LV origin using the robotic magnetic navigation system with the new magnetic ablation OICs. The use of the system seems to be feasible, safe, and efficacious for the treatment of VAs in a wide variety of conditions such as normal structural heart or cardiomyopathy with low ejection fraction. In this series, the follow-up was extended to 1 year and clinical success was 85%.
The study population
Conclusion
This large series of consecutive patients shows that catheter ablation of LV arrhythmias with a magnetic OIC and RMN system is effective.
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Cited by (36)
Remote magnetic navigation compared to contemporary manual techniques for the catheter ablation of ventricular arrhythmias in structural heart disease
2021, HeliyonCitation Excerpt :Furthermore, loss of follow-up in that study was much larger, with only 79/113 (70%) patients followed up after ablation. There have been no studies comparing RMN vs. manual ablation in solely NICM patients, but several studies have included relatively small numbers of NICM patients, ranging from 14–38 patients [5, 6, 8, 24]. In contrast, our study numbers of patients with NICM were much larger (n = 104 patients).
Electrophysiologic mapping and cardiac ablation therapy for prevention of ventricular tachycardia
2020, Emerging Technologies for Heart Diseases: Volume 2: Treatments for Myocardial Ischemia and ArrhythmiasSpecial Ablation Approaches: Epicardial, Other
2013, Cardiac Electrophysiology: From Cell to Bedside: Sixth EditionThe emerging role of epicardial ablation
2012, Cardiac Electrophysiology ClinicsCitation Excerpt :The presence of sinuses, recesses, and reflections are important to loop the catheters and direct them to the intended location. The advent of deflectable sheaths and robotic magnetic navigation has improved the ability to navigate in the pericardial space.29 This article discusses the importance of epicardial ablation for the commonly treated arrhythmias.
Remote magnetic navigation and arrhythmia ablation
2012, Archives of Cardiovascular DiseasesCitation Excerpt :A few studies on the efficacy of the treatment in cases of ischaemic ventricular arrhythmias have been published [26]. In addition, isolated cases have been reported in particular clinical situations, such as fascicular ventricular arrhythmia, ventricular extrasystoles localized at the level of the left anterior aortic sigmoid, left atrial arrhythmias or re-entrant arrhythmias associated with congenital cardiopathies and, finally, in the treatment of epicardial ventricular arrhythmias [27,35,40,43–45]. One of the principal advantages that emerged during our review of the literature is represented by the highly significant decrease in the duration of exposure to X-rays [22,41,42].