Wie erfolgreich ist die ambulante Elektrokonversion des therapieresistenten Vorhofflimmerns?

Abstract

Summary Between 1993 and 1997 in our out-patient clinic, a 135 direct current electrical cardioversions were performed in 88 patients with atrial fibrillation resistant to medical therapy. Cardioversion was done in short general anaesthesia with propofol (87%) or etomidate (13%). The pads were placed antero-posterior, a monophase shock energy of a mean 148 Joule was applied. Neither during cardioversion nor during 4 hours observation in the hospital serious complications ensued. Primary success, conversion to sinus rhythm, was achieved in 93% of cardioversion; within the 12 hours after cardioversion atrial fibrillation recurred in 11% of cases. In sinus rhythmus remained at 6, 12, 24, and 36 months 48%, 33%, 22% and 17% of the patients, respectively. Somewhat higher proportion of sinus rhythmus was found in 88 cases with the first cardioversion – at 6, 12, 24 and 36 months 54%, 40%, 27% and 27% of the patients, respectively. In univariate analysis previous atrial fibrillation episodes (p = 0.0075), previous cardioversion (p = 0.0137), digoxin before cardioversion (p = 0.0097), left atrium enlargement (>4.0 cm; p = 0.054), higher shock energy in Joule (p = 0.0021) and >1 shock (p = 0.0017) were correlated with atrial fibrillation recurrence during the follow-up. In multivariate Cox analysis left atrium size >4.0 cm (p = 0.023; RR = 0.26) and higher shock energy in Joule (p = 0.0082; RR = 1.006) were independent predictors of atrial fibrillation recurrence. Cardioversion can be performed ambulatory without major complications and is initial successful in >90% of drug resistant atrial fibrillation. Previous atrial fibrillation episodes, previous cardioversion, enlarged left atrium and high shock energy applied herald recurrence of atrial fibrillation in the follow-up. Short-term results can be improved by amiodarone and diuretics/ACE-blockers therapy in cases of heart failure. Long-term results of cardioversion are disappointing while only about 50% of the patients remains in sinus rhythmus after 6 months and even only 25%