Catheter ablation of paroxysmal atrial fibrillation (PAF) is an established therapy option for highly symptomatic patients failing conventional treatments. The standard procedure requires generous use of fluoroscopy in combination with 3-dimensional mapping systems to visualize the left atrium, causing high radiation exposure to patient and electrophysiologist in a time dependent manner. Newly introduced technology utilizing robotic navigation systems for catheter manipulation, allow operator to be removed from the radiation field and potentially reduce procedure duration.

The researchers evaluated this approach by randomizing 60 patients with drug refractory highly symptomatic PAF to Robotic Navigation, versus a conventional manual navigation for Atrial Fibrillation Ablation. Both groups were comparable in terms of gender, age, history of AF, duration of AF episodes, presence of structural heart disease, LA diameter, and LVEF.

In both groups surface and endocardial electrograms were monitored and stored. 3-D mapping for LA geometry acquisition was obtained with a standard protocol using a non-fluoroscopic navigation system. Venous access was obtained and a single transseptal puncture allowed Left Atrial access. Pulmonary Vein Isolation and r adiofrequency ablation was performed in a standard fashion to achieve complete electrical Pulmonary Vein disconnection. The control group required manual catheter manipulation by operator at the table. In the Robotic Navigation method pull wires are attached to the outer sheath and catheter tip and controlled by a joystick using the software interface from the control room.

Fluoroscopy time being the primary endpoint was measured at any time the operator entered the laboratory. Presence in the control room was considered as zero fluoroscopy exposure. Post procedure, all patients were left on weight based Heparin and Warfarin until INR was 2-3. Oral anticoagulation was continued for at least 3 months. All anti-arrhythmic medications were left off following the procedure.

The results showed overall fluoroscopy time was significantly lower in the robotic navigation compared to the conventional group. Mean time with robotic navigation was 9 minutes versus 22 minutes in conventional group. The preparation phase did not have any difference indicating placement of the robotic sheath in the LA does not require additional fluoroscopy. There was no significant difference in overall procedure duration between groups. At 6 month follow up, maintenance of Sinus Rhythm was similar in both groups.

The authors felt that the contributing factors for decrease in fluoroscopy time with robotic navigation were a combination of: 1. Operator being distanced from fluoroscopy source. 2. Improved stability of catheter tip in robotic sheath. 3. Favorable arrangement of procedural information leading to improved operator use of 3D mapping systems alone, instead of relying on fluoroscopy.

The authors concluded that, “The presented data indicate that PVI can safely and successfully be performed using robotic navigation.” (Steven et al. Reduced Fluoroscopy During Atrial Fibrillation Ablation: Benefits of Robotic Guided Navigation. J Cardiovasc Electrophysiol 2010; 21: 6-12.)