Myocardial Inotropic Function While Receiving Antiarrhythmic Ic Class Medications: Is It Worth Worrying About?

Atrial fibrillation (AF) is one of the most common arrhythmias among adults in economically developed countries of the world. This research aim was to study changes of contractile function of the myocardium in patients with AF during restoration of sinus rhythm (SR). Methods: In a one-center prospective study patients with AF received propaphenone or aethacizinum for 6 months after conversion to SR by planned or acute electrical cardioversion (ECV). Symptoms and safety were evaluated. Results: Of the 62 patients enrolled in the study, 57 completed it per protocol. 25 patients (44%) were admitted for ECV by emergency service, 32 (56%) were referred by a cardiologist or general practitioner. All 57 patients were followed up for 6-month period; 49 (86%) maintained SR group. The rest - 8 patients (14%) experienced =1 AF paroxysm (AF group) within the follow-up time. Between AF group and SR group echocardiographic data, early diastolic atrial myocardial velocity, and strain - no significant changes were found. No safety parameters changed significantly. Recurrence rate of AF in aethacizinum group compared to propafenone group (55,6% vs 72,5%) (p=0,05). Aethacizinum, propafenone may be safe in patients with persistent form of AF and have no negative impact on inotropic function of myocardium.