Robotic Ablation of Atrial Fibrillation

The overall goal of this procedure is to achieve an electrical isolation of the pulmonary veins from the left atrium to prevent recurrence of atrial fibrillation with a novel robotic ablation system. This is accomplished by first preparing the robotic catheter system. Next, the catheters are positioned in the left atrium with a transseptal puncture, then an angiography and 3D anatomical reconstruction of the left atrium is performed.

Finally, an ablation catheter is positioned in the left atrium and the pulmonary veins are encircled with the ablation catheter to achieve an electrical conduction block between pulmonary vein and atrium. Ultimately, the electrical conduction block is confirmed by stimulation inside the pulmonary vein, while the stimulus in the pulmonary vein does not excite left atrial myocardium Catheter. Ablation of atrial fibrillation is a complex procedure with a relatively long duration and with substantial fluoroscopy exposure for the patient and the medical staff.

The main advantage of this procedure is that radiation exposure is limited to the first steps of the procedure and the operator stays out of the radiation field the main part of the procedure. Furthermore, catheter stability is improved due to the fact that all further movements of the catheter are performed via the remote control and the robotic arm, and, and this technique allows fast switching between manual ablation and robotic ablation, and therefore combines the advantage of robotic ablation and manual ablation. The protocol presented here is the standard approach of robotic catheter ablation RCS at the Department of Cardiology Berlin Camp.

The protocol and analysis of procedures and patient outcomes was approved by the local ethics committee of the Shati Berlin. The remote catheter system or RCS consists of a remote catheter manipulator, which is a robotic arm that can be moved by remote control. Attach the robotic arm to the operating table as previously described to prepare for pre ablation.

Position the patient on the operating table and use a 0.3 milligram per kilogram bolus of midazolam and a four milligram per kilogram per hour continuous infusion of propofol to induce deep sedation. Now attach 12 lead ECG and surface electrodes for the 3D mapping system to the body of the patient. Then prepare the following materials for surgery, a transseptal needle and an 8.5 FSLO sheath with guide wire A six F and a seven F 25 centimeter sheath, a dec apolar, and a circular steerable diagnostic catheter, an open irrigated ablation catheter and an ablation generator.

Also prepare a contrast syringe and a pericardial synesis tray for acute treatment of complications. Next position the robotic arm of the system in a sterile drape and ready to use. Then attach the handheld remote controller to the robotic arm with six F seven F and 8.5 F sheath.

Perform a bilateral venous puncture to obtain venous axis and place a de apolar diagnostic catheter in the coronary sinus or cs. Then under fluoroscopic guidance, use an 8.5 F long SLO sheath and a 71 centimeter transseptal needle. To perform a transseptal puncture, remove the needle and introduce a guide wire via the transseptal sheath in the left superior pulmonary vein.

Then draw back the sheath in the inferior vena cva. Using the wire as a guide place an 8.5 F long SRO sheath with the wire in the left atrium or LA to the fossa vallas, and the LA advance. An open irrigated ablation catheter with contact force measurement via the SRO sheath to the la.

After administering a bolus of heparin, administer heparin at a rate of 15 international units to maintain an activated clotting time of 300 to 350 seconds throughout the procedure. Once the ablation catheter has entered the la, introduce the sheath into the la, remove the G wire and dilator of the SLO sheath and place the ablation catheter in the left ventricle. Next, perform LA angiography over the sheath while using the ablation catheter for high rate ventricular pacing to enhance contrast opacification.

Then via the long sheath, advance the circular mapping catheter into the LA while using a computerized mapping system for registration of the movement in relation to a reference electrode, create a 3D anatomical reconstruction of the LA by moving the circular catheter on the inner surface of the la all of the four PVS and the left atrial appendage. Place the circular mapping catheter in the right superior PV to record PV potentials and confirm a conduction block After PV isolation or PVI then draw back the ablation catheter from the left ventricle to the left atrium to carry out catheter ablation as wide antral circumferential ablation. Position the handle of the ablation catheter in the robotic arm of the amigo system.

Use a maximum temperature of 43 degrees Celsius and a maximum power of 35 watts, septal of 25 watts posterior wall respectively, and a flow rate of 17 milliliters per minute. With use of the remote control from outside the radiation field, manipulate the ablation catheter creating point by point lesions around the left and right PV osteo. Measure contact force during ablation.

Then use the local electrogram amplitude reduction recorded on the tip of the ablation catheter elimination or dissociation of the PV electrograms on the circular catheter and entry exit block. As ablation endpoints, mark each ablation point on the 3D reconstruction. Confirm conduction block for every single PV by recording potentials on the circular mapping catheter inside the PV or the entry block, and by pacing from inside the PV without capture of the atrium or the exit block.

When ablation procedure complete stop propofol infusion and remove all catheters. Measure a CT and if greater than 300 seconds, administer 3000 international units of protamine before removing the sheaths. Manually compress the puncture site for 10 minutes and until the bleeding stops, place a pressure dressing in the groin and advise the patient to lay still for eight hours.

Transfer the patient to a step down unit and monitor for four hours and until fully responsive, administer anticoagulant and perform transthoracic echocardiography. According to the text protocol in this table, the characteristics and clinical data of the first 21 patients who received PVI with RCS are shown comparison of procedure duration, total fluoroscopy time and operator fluoroscopy exposure duration was performed to analyze procedural improvement. As experience grew with the technique as shown here, mean duration of cases 11 through 20 was significantly reduced compared to cases one through 10 while reduction of total fluoroscopy time and operator fluoroscopy exposure time did not reach significance.

However, operator fluoroscopy exposure was significantly reduced in RCS performed ablations as compared to those performed using the standard ablation procedure. When compared in a recent study, This technique can be done in less than two hours. If performed properly, the ablation can be performed with adequate contact force and conduction block can be achieved in all pulmonary veins.

Therefore, this technique is not inferior to manual ablation in terms of procedural success and duration.