Reversal of Electrical Remodeling After Cardioversion of Persistent Atrial Fibrillation

Abstract

The atrial effective refractory period increases, sinus node function improves, and atrial conduction velocity goes up in the first week after cardioversion of long-standing atrial fibrillation in humans. Reverse electrical remodeling of the effective refractory period occurs at different rates in different regions of the atrium.

2012 HRS/EHRA/ECAS Expert Consensus Statement on Catheter and Surgical Ablation of Atrial Fibrillation: Recommendations for Patient Selection, Procedural Techniques, Patient Management and Follow-up, Definitions, Endpoints, and Research Trial Design

“…The evidence in support of this conclusion is based on changes in atrial APD, ERP, CV, and P wave duration when measured 1–4 weeks after achieving sinus rhythm. 617,618,619,620 The changes in P wave duration occur more slowly and do not predict long-term maintenance of sinus rhythm. 619 An important question is whether AAD therapy can be used to prevent or initiate reverse remodeling even prior to ablation, thereby improving the success rate for ablation procedures.…”

“…One study reported that the recurrence rate of AF following ablation was lower when treatment with dofetilide prior to ablation reduced the burden of AF, and was associated with a decrease in P wave duration. 617,618 Another single-center nonrandomized study found that amiodarone prolonged the cycle length of AF and reduced the time spent on CFAE ablation, but it did not have any effect on long-term outcomes. 619 A second single-center study treated patients with Class I or III drugs for long-standing persistent AF and compared the outcomes of ablation in those who were successfully converted to sinus rhythm months prior to ablation as opposed to those who were not.…”

Remodelagem atrial elétrica reversa após cardioversão de fibrilação atrial isolada de longa duração

“…Recovery has also been demonstrated in human atria 3,[23][24][25][26] . On the other hand, a remarkable vulnerability to recurrence during post-cardioversion period has been observed while reverse remodeling is yet incomplete 23 .…”

“…Most studies about electrical atrial remodeling in humans have assessed subjects with and without overt cardiovascular disease [23][24][25]27 . Although micro structural atrial changes have been observed in lone AF 29 , gross and ultra-structural anatomic changes due to underlying cardiac disease, such as fibrosis, may persist indefinitely, despite the restoration to sinus rhythm and may be responsible for persistent electrophysiological abnormalities.…”

“…On the other hand, a remarkable vulnerability to recurrence during post-cardioversion period has been observed while reverse remodeling is yet incomplete 23 . However, the necessary time to completely restore atrial electrophysiological properties, especially the conduction velocity, is yet to be defined.The methods employed for electrophysiological analysis are usually invasive [23][24][25]27 and make consecutive analysis of the same subject difficult, generating limitations to determine the moment of complete reversal remodeling. Furthermore, little is known about the effects of antiarrhythmic drugs on the remodeling process, especially amiodarone, frequently used in order to facilitate cardioversion and maintain sinus rhythm 28 .…”