Successfulness of two pharmacological strategies for conversions of recent-onset atrial fibrillation and perspectives of local drug delivery

Introduction. Pharmacological conversion of recent-onset atrial fibrillation is important practical issue. Related to question of the ESC WG on Cardiovascular Pharmacology and Drug Therapy ‘how to best achieve cardioversion’, we analyzed successfulness of a single drug and sequential drug administration strategies. Furthermore, we tried to enhance the review with an idea on increasing the efficacy of conversion by local delivery of drugs. Methods. A systematic review of controlled trials, published in indexed journals, with antiarrhythmic drugs (of a class III, IC and IA, and atrial-selective) was performed. Eligible studies had to be randomized, controlled, parallel-designed, human trials that prove efficacy of pharmacological cardioversion of recent-onset atrial fibrillation. Results. High diversity in conversion rate of a single antiarrhythmic drug administration is shown, depending on drug dosage and time of its application. Sequential drug administration showed high success rate, but higher time consumption. Conclusion. Atrial-selective drugs have rapid onset of action, but sequential administration of older antiarrhythmic drugs shows excellent success rate. To enhance short-term success rate, local delivery of atrial-selective drugs may be needed. Possible models are proposed.