Background: Low-energy internal cardioversion (LEIC) is a safe and effective procedure for the restoration of sinus rhythm in patients with atrial fibrillation refractory to external cardioversion. However, the procedure needs fluoroscopy and the use of the electrophysiology laboratory, even when the esophageal approach is utilized. The aim of this study was to assess the efficacy, safety and tolerability of a new simplified procedure of esophageal LEIC performed without fluoroscopy, outside the electrophysiology laboratory.
Methods: Thirty consecutive patients (23 males, 7 females) with persistent atrial fibrillation were submitted to LEIC using a step-up protocol (by steps of 50 V, starting from 200 V). Twenty (66%) were resistant to external cardioversion. A large surface area lead (cathode) was positioned within the esophagus, 45 cm from the nasal orifice. A second large surface area lead (anode) was positioned in the right atrium via the right internal jugular vein without fluoroscopic control. Synchronization of delivery of the shock with the QRS was achieved by means of two cutaneous electrodes positioned on the thoracic wall.
Results: Sinus rhythm was restored in 28 patients (93%) with a mean delivered energy of 15.2 +/- 7.5 J (range 5-27 J) and a mean impedance of 48.3 +/- 5.6 Ohm. No complication occurred during and after the procedure that was well tolerated under sedation.
Conclusions: This new technique of performing esophageal LEIC is effective and seems to be safe and well tolerated. In this way internal cardioversion can be performed without fluoroscopy, outside the electrophysiology laboratory.