Pharmacological Cardioversion with Cavutilide: Results of Restoration and Maintenance of Sinus Rhythm in Certain Categories of Patients with Atrial Fibrillation and Atrial Flutter

Background/Objectives: Atrial fibrillation (AF) and atrial flutter (AFl) are common arrhythmias associated with significant morbidity and mortality. Pharmacological cardioversion (PCV) is an alternative to electrical cardioversion (ECV), particularly in patients with contraindications or prior unsuccessful ECV. This study aimed to evaluate the short- and long-term efficacy and safety of Cavutilide for PCV in patients with AF/AFl, including those with obesity and previous failed ECV. Methods: In this prospective, open-label, single-center study, 193 consecutive patients with paroxysmal or persistent AF/AFl underwent PCV with intravenous Cavutilide (maximum total dose 30 µg/kg). Patients were stratified into three groups: obesity (n = 56), prior unsuccessful ECV (n = 50), and control (n = 87). Sinus rhythm (SR) restoration, early recurrence (within 24 h), adverse events, and long-term recurrence rates were assessed during a follow-up period of up to 19 months. Results: SR was restored in 89.6% of patients overall, including 87.5% in obese patients and 78% in those with prior failed ECV. The first dose was effective in 49.2% of cases. Early recurrence occurred in 5.2% of patients. During follow-up, AF/AFl recurrence was documented in 33.7% of patients, most frequently within the first 3 months. Restoration of SR with the lowest dose (10 µg/kg) was associated with a higher recurrence risk (OR 1.92; 95% CI 1.01–3.71; p = 0.03). Serious adverse events were infrequent; torsades de pointes occurred in 1.5% of patients. Conclusions: Cavutilide is effective for pharmacological cardioversion of AF/AFl, including in patients with obesity and prior unsuccessful ECV, with an acceptable safety profile. Careful monitoring is warranted due to the risk of proarrhythmic events and arrhythmia recurrence, particularly in the early post-cardioversion period.