Management of atrial fibrillation in cardiac resynchronization therapy - Clinical practice of CRT: how to improve the success rate

Background Mortality in severe congestive heart failure rises with the incidence of an inter- and intraventricular conduction delay and doubles if atrial fibrillation (AF) occurs. Electrical cardioversion (CV) is frequently regarded as less promising in these patients. Encouraged by first conversions during defibrillation threshold (DFT) testing we consecutively attempted electrical cardioversion in 30 patients selected for cardiac resynchronization therapy (CRT). Methods After successful CV an additional atrial electrode was placed during implantation of a CRT device (ICD or pacemaker) to ensure AV sequential biventricular pacing. Regular clinical follow-up examinations up to 2 years were performed. Results In 23 (75%) of 30 patients (onset of AF at least 6 months earlier), sinus rhythm (SR) could successfully be restored. Under antiarrhythmic medication in 21 patients SR was still present after 333 +/- 142 days. Furthermore, a significant increase of EF from 22% to 31% (P < 0.05) with an accompanying significant increase of the VO2max from 12.9 to 16.1 ml/kg/min (P < 0.05) was measured. Conclusion In CRT candidates with supposed permanent AF more vigorous external or internal cardioversion attempts are justified. In the majority of patients SR can be established and persists for at least 1 year with a superproportional improvement in functional capacity. (C) 2004 The European Society of Cardiology. Published by Elsevier Ltd. AtI. rights reserved.