Clinical Evaluation of a Policy of Early Repeated Internal Cardioversion for Recurrence of Atrial Fibrillation SIMON P. FYNN, M.B., DERICK M. TODD, M.B., W. JULIAN C. HOBBS, M.B., KAREN L. ARMSTRONG, ADAM P. FITZPATRICK, M.D., and CLIFFORD J. GARRATT, D.M. From the Manchester Heart Centre, Manchester Royal Inrmary, Manchester, United Kingdom Early Repeated Cardioversion for AF Recurrence. Introduction: The clinical value of cardio- version (CV) of persistent atrial brillation (AF) is limited by the high rate of early AF recurrence, which may be related to the persistence of atrial electrical remodeling. We examined the hypothesis that the likelihood of maintaining sinus rhythm after CV of persistent AF is signicantly enhanced by a policy of early repeated CV. Methods and Results: Fifty-nine patients with persistent AF underwent internal CV (CV 1). Those patients cardioverted were monitored with daily transtelephonic ECG. In the event of AF recurrence, these patients were admitted rapidly for repeat CV (CV 2) and, if further recurrence occurred, a third CV (CV 3) was performed. Daily ECG monitoring was continued until 1 month of sinus rhythm was maintained or a total of three CVs were performed. Of the 59 patients undergoing CV 1, 43 were discharged in sinus rhythm and 29 subsequently had AF recurrence during monitoring. Twenty-three of these underwent CV 2 and 11 of these underwent CV 3. Of those having repeated CVs, only 4 patients maintained sinus rhythm for 1 month (3 after CV 2 and 1 after CV 3). The remaining patients had repeated AF recurrence during the monitoring period. Mean time from AF recurrence to CV 2 was 20 6 13 hours and from AF recurrence to CV 3 was 13 6 7.2 hours. Atrial effective refractory periods increased from 189 6 16 msec at CV 1 to 215 6 18 msec at CV 3 (P < 0.05), indicating reversal of atrial electrical remodeling during this period. Conclusion: A policy of early repeated CVs for AF recurrence has very limited clinical value despite evidence of reversal of atrial electrical remodeling. The time between AF recurrence and repeat CV may need to be reduced further if such a policy is to succeed. (J Cardiovasc Electrophysiol, Vol. 13, pp. 135-141, February 2002) arrhythmia, atrial brillation, cardioversion, recurrence, atrial electrical remodeling Introduction Electrical cardioversion is an effective treatment for pa- tients with persistent atrial brillation (AF), restoring sinus rhythm in approximately 90% of cases. 1 However, the long- term maintenance of sinus rhythm following cardioversion is poor, irrespective of the use of antiarrhythmic therapy. 2-8 Studies have consistently documented that the rate of AF recurrence is highest in the rst few weeks after cardiover- sion, and thereafter the recurrence rate is markedly re- duced. 9,10 This may be due to the persistence of AF-induced electrical changes (termed atrial electrical remodeling) that, although initially rendering the atria more vulnerable to brillation after cardioversion, 11-13 have been shown to re- verse during a subsequent period of sinus rhythm. 11,14-16 It follows, therefore, that a treatment strategy aimed at main- taining patients in sinus rhythm in the period following cardioversion, during remodeling reversal, may lead to a reduction in the subsequent likelihood of AF recurrence. In a previous article, we documented the reversal of atrial electrical remodeling that occurs between an initial cardio- version and repeat cardioversions for AF recurrence. 14 The aim of this article is to describe the clinical value of this policy of repeated early cardioversion, i.e., whether this policy is likely to result in long-term sinus rhythm. Methods Patient Selection All consecutive patients presenting with persistent AF (minimum duration 3 months) documented by serial ECG were considered for the study. Written informed consent was obtained using an information sheet and consent form approved by the Central Manchester Research Ethics Com- mittee, which also approved the protocol. Internal cardio- version of AF is the preferred method in our institution. This applies to all patients referred for cardioversion of AF, irrespective of whether they had a previous failed external cardioversion. However, if patients are reluctant to undergo cardioversion by the internal route, they are offered external cardioversion as an alternative. Planned exclusion criteria for the study were a contraindication to anticoagulation and pregnancy. Patients with a prosthetic heart valve were con- sented only for an initial internal cardioversion (CV 1) due to the potential risks of repeated invasive procedures in such patients. Drs. Fynn, Todd, and Hobbs are supported by the British Heart Foundation. Address for correspondence: Clifford J. Garratt, D.M., Manchester Heart Centre, Oxford Road, Manchester, United Kingdom, M13 9WL. Fax: 44-161-276-4443; E-mail: Clifford.Garratt@mhc.cmht.nwest.nhs.uk Manuscript received 24 August 2001; Accepted for publication 18 Decem- ber 2001. 135 Reprinted with permission from JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Volume 13, No. 2, February 2002 Copyright ©2002 by Futura Publishing Company, Inc., Armonk, NY 10504-0418