Objective: External electrical cardioversion is commonly used in the management of atrial fibrillation (AF), but usually involves general anaesthesia. We tested the efficacy, safety and tolerability of a minimally invasive cardioversion technique, not requiring general anaesthesia, performed on an outpatient basis.
Methods: We performed outpatient oesophageal cardioversion in 87 consecutive patients (mean age: 67.5 +/- 9.6 years; weight: 77.47 +/- 12.34 kg; left atrium diameter: 46.25 +/- 6.85 mm; LVEF: 55.5 +/- 16%) with persistent AF (mean duration: 6.99 +/- 11.55 months). A biphasic shock was delivered via an oesophageal decapolar lead (cathode) and two precordial patches (anode) under a mild sedation (midazolam 2.5-5 mg). In the first 25 patients, a step-up protocol (from 10 to 100 J) was performed whereas, in the other 62, a first shock at 50 J and a second one at 100 J, were delivered.
Results: Patients described the level of discomfort caused by the procedure according a five-grade scale. Cardioversion was achieved in 97.7% of patients using a mean effective energy of 51.2 +/- 15.7 J. In 88.5% of patients, sinus rhythm was restored by using 50 J or less. No complications occurred and no patient required hospital admission. Mean discomfort score was 1.56 +/- 0.74 out of 5. Sinus rhythm persisted in 62.6% of patients at the 1-month follow-up.
Conclusions: Outpatient oesophageal cardioversion is a safe, acceptable and effective way to cardiovert patients with AF. It may be a useful alternative to external cardioversion. A relatively high starting energy (50 J) was demonstrated to be superior to a low-energy step-up technique.