title: Angiotensin receptor blocker as adjunctive therapy for rhythm control in atrial fibrillation: results of the irbesartan-amiodarone trial.
abstract: Atrial fibrillation (AF) is a common arrhythmia associated with increased risk of stroke and mortality. The early appearance of electrical remodeling is followed by structural remodeling of the atrial tissue. Direct current cardioversion of persistent AF is the most effective treatment for the restoration of sinus rhythm, but it is hampered by a high percentage of recurrences. Recurrences may be the consequence of both electrical and structural remodeling. A study on the use of irbesartan to maintain sinus rhythm in patients with long-lasting persistent AF showed that this angiotensin II receptor blocker combined with amiodarone prolonged sinus rhythm after cardioversion. Irbesartan may have antifibrotic effects due not only to the ability to diminish the synthesis of collagen type I molecules but also to its capacity to stimulate the degradation of collagen type I fibers, as has been demonstrated with losartan, another angiotensin II receptor blocker. This suggests that efforts to reduce the structural changes that occur during AF may be more useful in preventing recurrences than efforts designed to minimize the electrical changes alone. The AFFIRM trial compared two approaches to the treatment of AF: cardioversion with antiarrhythmic drugs to maintain sinus rhythm and the use of rate-controlling drugs. The results show that management of AF with the rhythm-control strategy offers no survival advantage over the rate-control strategy. However, non-antiarrhythmic drugs to prevent recurrences, like irbesartan, were not controlled and amiodarone was used in a low percentage of the patients. The treatment strategies proposed in both AFFIRM and RACE, in our opinion, may not be the optimal. The modern clinical approach to AF involves an early intervention to restore sinus rhythm, therefore preventing atrial remodeling. The pretreatment of patients with AF who undergo electrical cardioversion is very important and will be the subject for continuous improvement.
authors.affiliation: Arrhythmia Unit, Ramón y Cajal Hospital, Department of Medicine, Alcalá University, Madrid, Spain.
authors.forename: Antonio H
authors.initials: AH
authors.lastname: Madrid
authors.forename: Carlos
authors.initials: C
authors.lastname: Escobar
authors.forename: José María G
authors.initials: JM
authors.lastname: Rebollo
authors.forename: Irene
authors.initials: I
authors.lastname: Marín
authors.forename: Enrique
authors.initials: E
authors.lastname: Bernal
authors.forename: Sebastián
authors.initials: S
authors.lastname: Nannini
authors.forename: Lilianna
authors.initials: L
authors.lastname: Limón
authors.forename: Jian
authors.initials: J
authors.lastname: Peng
authors.forename: Concepción
authors.initials: C
authors.lastname: Moro
mesh_terms: D000638:Amiodarone / Q000627:therapeutic use*; D047228:Angiotensin II Type 1 Receptor Blockers; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use*; D001281:Atrial Fibrillation / Q000188:drug therapy; D001713:Biphenyl Compounds / Q000627:therapeutic use*; D004359:Drug Therapy, Combination; D006801:Humans; D000077405:Irbesartan; D016032:Randomized Controlled Trials as Topic; D013777:Tetrazoles / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D047228:Angiotensin II Type 1 Receptor Blockers; D000889:Anti-Arrhythmia Agents; D001713:Biphenyl Compounds; D013777:Tetrazoles; D000077405:Irbesartan; D000638:Amiodarone