When Robotics Makes the Difference: Robotic Magnetic Navigation Offers Advantages in Retrograde Approach During Catheter Ablation of Left-Sided Accessory Pathways: (Case Report)

Krista Lesina, MD; Rita B Gagyi, MD; Tamas Szili-Torok, MD, PhD Department of Cardiology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands

Funding sources: none 

Case Description

A 57-year-old female with a history of palpitations, dizziness and documented supraventricular tachycardia on a 24-hour Holter recording was referred for anelectrophysiology study (EPS) and catheter ablation (CA).Her ECG showed pre-excitation consistent a left lateral accessory pathway. After EPS confirmed the presence of a left-sided pathway CA was undertaken utilizing a transseptal access. Although the first procedure was acutely successful, she developed recurring symptoms with recurrent delta wave on her ECG. The repeated CA was planned using retrogrademapping.


A. The 12-lead electrocardiogram before the catheter ablation shows sinus rhythm (QRS 97 ms, PR interval 129 ms) and pre-excitation consistent with a left lateral accessory pathway.

B. Fluoroscopy image of the catheter position during the first CA procedure indicating a small left atrium with limited space between the ablation target and the tip of the Agilissteerable sheath. (red arrow, LAO view).

C. Redo catheter ablation with RMN Magnoflush catheter (Med Fact engineering GmbH, Lörrach, Germany)utilizing the retrograde approach. Taking advantage of the floppy and flexible catheter design four different-sized loops could be achieved resulting in a very stable position in a more antero-lateral and stable catheter than during the first procedure. Red arrows show the excessive curves on the magnetic catheter in a LAO view.

D. 12-lead electrocardiogram after the catheter ablation shows sinus rhythm (QRS 90 ms, PR interval 135 ms) and normal atrioventricular conduction without pre-excitation.

Discussion and Conclusion

The main message of this case report is that the retrograde approach can be performed successfully using the robotic magnetic navigation (RMN) system (Niobe, Stereotaxis Inc., St. Louis, MO, USA).The RMN system offers several possible advantages including atraumatic catheter design and superior navigation capabilities with stable catheter positioning. When using the RMN, it is possible to gain access to difficult anatomy, and even a minor dislocation may bring the catheter into a close proximity to the conduction system or to another important cardiac structure(1). The RMN catheter allows for reliable contact without increased risk of perforation and it maintains stable contact throughout the cardiac cycle even in the face of changes in cardiac rhythm (2). Furthermore, it is possible to easily make several consecutive bends in different directions with the robotically guided catheter. Using the RMN system there is no need to develop specially curved catheters(3). In this report as presented on the figure, using a transseptal approach due to the small size of the atrium, there was not enough space between the tip of the sheath and the target location. While using the retrograde approach, with multiple curves we gained enough space to get to the target location maintaining the catheter in a stable position. These curves are impossible to perform with manually guided catheters.


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