Factors associated with one-year maintenance of sinus rhythm after successful electrical cardioversion of persistent atrial arrhythmias in patients with cardiac implantable electronic devices
N Brankovic, G Milasinovic, B Kircanski, N Vujadinovic, V Koic, K Zivic, N RadovanovicAbstract
Background
A substantial proportion of patients with cardiac implantable electronic devices (CIEDs) develop persistent atrial fibrillation (AF) or atrial flutter (AFL). Although electrical cardioversion (ECV) is highly effective in restoring sinus rhythm (SR), its long-term maintenance in this population remains a significant clinical challenge.
Purpose
To identify factors associated with a higher likelihood of maintaining SR one year after successful ECV of persistent AF and AFL in patients with CIEDs.
Methods
This is retrospective, observational study, performed among patients with CIEDs who underwent elective ECV of persistent AF or AFL between January 2011 and June 2023. All procedures were performed under intravenous analgosedation in the presence of an internal medicine specialist and anesthesiologist. In patients with an implantable cardioverter defibrillator (ICD), it always started with a maximum-energy internal shock, and if it was unsuccessful, up to 2 additional maximum external shocks were delivered. In all other patients, an external defibrillator with anterolaterally placed electrodes was used. If the first shock was ineffective, subsequent shocks were delivered at maximum energy, with up to three total shocks. The procedure was considered successful if SR was confirmed on two ECG tracings, obtained immediately after ECV and 30 minutes later. During follow-up, asymptomatic patients underwent an ECG and device interrogation at regular check-ups, while those who experienced arrhythmia or had recorded atrial high-rate episodes were actively screened for atrial arrhythmias using ECG Holter monitoring.
Results
This study included 144 ECV procedures, each performed on a different patient (mean age 66.0±10.4 years, 79.9% male). An antibradycardia pacemaker was implanted in 108 patients, ICD (single or dual chamber) in 18 patients, and a cardiac resynchronization pacemaker in 18 patients (CRT-P in 8 and CRT-D in 10). ECV was successful in 129 patients (89.6%), and SR was maintained one year after the procedure in 49 of them (38.0%). Using multivariate logistic regression analysis we determined factors independently associated with a higher likelihood of maintaining SR one year after successful ECV: shorter total duration of atrial arrhythmia (OR = 0.962; 95%CI: 0.93-0.99: p = 0.017), non-smoking status (OR = 0.098; 95%CI: 0.03-0.34; p < 0.001), absence of hypothyroidism (OR = 0.038; 95%CI: 0.01-0.42; p = 0.021), CHA2DS2-VASc score ≤ 3 (OR = 0.097; 95%CI: 0.02-0.43; p = 0.002), and absence of previous ECV (OR = 0.069; 95%CI: 0.01-0.48; p = 0.007).
Conclusion
Patients with CIEDs, who are non-smokers and have fewer comorbidities, particularly without hypothyroidism, are good candidates for long-term maintenance of SR after ECV of persistent atrial arrhythmias. However, when the arrhythmia has a longer duration or ECV has already been performed, ECV is not the procedure of choice.