Cardiovascular Journal of Africa: Vol 32 No 6 (NOVEMBER/DECEMBER 2021)

CARDIOVASCULAR JOURNAL OF AFRICA • Volume 32, No 6, November/December 2021 AFRICA 327 Review Article Efficacy of amiodarone for the prevention of atrial fibrillation recurrence after cardioversion Sabina Istratoaie, Octavia Sabin, Ș tefan C Vesa, Gabriel Cismaru, Valer I Donca, Anca D Buzoianu Abstract The restoration and maintenance of sinus rhythm is a desir- able strategy for many patients with atrial fibrillation (AF) since it has been associated with improvement in symptoms and a better quality of life. Sinus rhythm can be achieved by pharmacological or electrical cardioversion or after catheter ablation of AF. Despite high rates of successful cardioversion, AF recurrence remains a major challenge. Anti-arrhythmic drug therapy currently plays a significant role in maintaining sinus rhythm after cardioversion. Amiodarone is the most commonly prescribed anti-arrhythmic drug for patients with AF. This is due to its particular electrophysiological proper- ties and superior anti-arrhythmic effects in comparison with other anti-arrhythmic drugs. Understanding the cardiac elec- trophysiology and arrhythmogenesis mechanisms may result in identification of new targets for anti-arrhythmic therapy. The aim of this article was to review amiodarone’s clinical pharmacology and evaluate evidence supporting amiodarone for treatment and prevention of AF recurrence after cardio- version. Keywords: amiodarone, atrial fibrillation, conversion, electro- physiology Submitted 29/6/20, accepted 4/12/20 Published online 14/1/21 Cardiovasc J Afr 2021; 32 : 327–338 www.cvja.co.za DOI: 10.5830/CVJA-2020-060 Atrial fibrillation (AF), the most common sustained cardiac arrhythmia, is a major cause of cardiovascular morbidity and mortality due to stroke, heart failure and sudden death. 1 A recent study estimates that in 2016, 7.6 million people over 65 years in the European Union had AF, and by 2060, this will increase by 89% to 14.4 million. This corresponds to a 22% increase in AF prevalence, from 7.8 to 9.5%. 2 Several randomised trials investigated the two treatment strategies for patients with AF, rhythm control with restoration and maintenance of sinus rhythm (SR) versus ventricular rate control by lowering the heart rate: AFFIRM (Atrial Fibrillation Follow-up of Rhythm Management), HOT-CAFE (How to Treat Chronic Atrial Fibrillation), PIAF (Pharmacological Intervention in Atrial Fibrillation), RACE (RAte Control versus Electrical conversion) and STAF (Strategies of Treatment of Atrial Fibrillation). 3-7 Results from these studies showed that the rhythm-control strategy was no more efficient than rate control in terms of stroke and mortality. However, restoration and maintenance of normal SR has been associated with an improved tolerance to exercise and a better quality of life. Approaches to restore SR include anti-arrhythmic drugs (AADs), electrical cardioversion and catheter ablation. High recurrence rate of AF has been reported after cardioversion, highlighting the need for AADs. Multiple AADs are available for AF rhythm control, the choice of drug being driven by the AAD’s reported efficacy, patient co-morbidities and risks of side effects. Amiodarone was first used in cardiology in 1962 as an anti-anginal agent. Five years later it was withdrawn due to its side effects. Afterwards, in 1974 it was re-introduced for its anti-arrhythmic effects both for atrial and ventricular arrhythmias. Amiodarone has been largely used for pharmacological cardioversion of AF and for maintenance of SR after direct current cardioversion (DCC) or catheter ablation. Amiodarone is also particularly used in patients with concomitant AF and impaired left ventricular function or underlying ischaemic heart disease. This review aimed to evaluate the accumulated data on amiodarone’s efficacy and safety for the treatment and prevention of AF recurrence after cardioversion. It also examined the particular pharmacological characteristics of amiodarone that are thought to play a role in the superior anti-arrhythmic effects in comparison with other anti-arrhythmic drugs. We conducted a review of the medical literature, which included all relevant articles published between 1978 and October 2019 using the MEDLINE, EMBASE databases and the COCHRANE library. To achieve different aims, we used several MeSH terms for our search strategy. For evaluating the efficacy Department of Pharmacology, Toxicology and Clinical Pharmacology, Iuliu Ha ţ ieganu University of Medicine and Pharmacy, Cluj-Napoca, Romania Sabina Istratoaie, MD Octavia Sabin, MD, PhD Ș tefan C Vesa, MD, PhD Anca D Buzoianu, MD, PhD 5th Department of Internal Medicine, Cardiology – Rehabilitation, Iuliu Ha ţ ieganu University of Medicine and Pharmacy, Cluj-Napoca, Romania Gabriel Cismaru MD, PhD, gabi_cismaru@yahoo.com Department of Geriatrics – Gerontology, Iuliu Ha ţ ieganu University of Medicine and Pharmacy, Cluj-Napoca, Romania Valer I Donca, MD, PhD