Factors associated with short- and long-term maintenance of sinus rhythm after successful elective electrical cardioversion

Introduction Electrical cardioversion (ECV) effectively restores sinus rhythm in patients with persistent atrial fibrillation (AF) and atrial flutter (AFL), although arrhythmia recurrence is common. We aimed to identify factors associated with a higher probability of maintaining sinus rhythm one month after successful ECV, and after one year in those who were arrhythmia-free after the first month. Methods This retrospective, single-center study included patients who underwent elective ECV for persistent AF or AFL between January 2011 and June 2023. Clinical, electrocardiographic, and echocardiographic characteristics were analyzed to identify parameters associated with the maintenance of sinus rhythm. Results We included 297 ECV procedures. ECV was successful in 91.9% of patients and sinus rhythm was maintained in 89.7% of them at one month and in 40.3% at one year follow-up. Shorter arrhythmia duration (OR = 0.863, 95% CI: 0.76–0.98, p = 0.026) and ventricular pacing on the pre-procedural ECG (OR = 5.212, 95% CI: 1.16–23.48, p = 0.032) were associated with one-month success. Factors associated with one-year sinus rhythm maintenance in patients who were in sinus rhythm during monthly follow-up were smaller left atrial dimensions (OR = 0.817, 95%CI: 0.77–0.98, p = 0.022), the first-ever arrhythmia episode (OR = 3.320, 95%CI: 1.10–10.05, p = 0.034), lower CHA 2 DS 2 -VASc score (OR = 0.132, 95%CI: 0.03–0.54, p = 0.005), non-smoking status (OR = 0.120, 95%CI: 0.04–0.37, p < 0.001), no previous ECV (OR = 0.082, 95%CI: 0.01–0.47, p = 0.005), and antiarrhythmic therapy (OR = 2.486, 95%CI: 1.01–8.65, p = 0.05). Conclusions ECV is a reasonable rhythm-control strategy in AF/AFL particularly when performed early after arrhythmia onset, in non-smokers and patients with fewer comorbidities, antiarrhythmic treatment, smaller left atrium and no prior ECV.