Pluymaekers NAHA, et al. - As atrial fibrillation often stops naturally, researchers examined if restoring sinus rhythm immediately is needed for patients with recent-onset atrial fibrillation. Outcomes of this multicenter, randomized, open-label, noninferiority trial suggest the noninferiority of a wait-and-see approach to early cardioversion in returning to sinus rhythm at 4 weeks in these patients.

Methods

• Patients with hemodynamically stable, recent-onset (<36 hours), symptomatic atrial fibrillation in the emergency department were randomly assigned to be treated with a wait-and-see approach (delayed-cardioversion group) or early cardioversion.
• Initial treatment with rate-control medication only and delayed cardioversion if the atrial fibrillation did not resolve within 48 hours, were provided to patients in delayed-cardioversion group.
• The presence of sinus rhythm at 4 weeks was assessed as the primary end point.
• They defined noninferiority as the lower limit of the 95% confidence interval for the between-group difference in the primary end point in percentage points more than −10.

Results

• The presence of sinus rhythm at 4 weeks occurred in 193 of 212 patients (91%) and 202 of 215 (94%) in the delayed-cardioversion group and the early-cardioversion group, respectively (between-group difference, −2.9 percentage points; 95% confidence interval [CI], −8.2 to 2.2; P=0.005 for noninferiority).
• In the delayed-cardioversion group, 150 of 218 patients (69%) had conversion to sinus rhythm within 48 hours spontaneously and 61 patients (28%) had after delayed cardioversion.
• In the early-cardioversion group, 36 of 219 patients (16%) had conversion to sinus rhythm spontaneously before the initiation of cardioversion and 171 patients (78%) had after cardioversion.
• Atrial fibrillation recurred in 49 of 164 patients (30%) in the delayed-cardioversion group and in 50 of 171 (29%) in the early-cardioversion group among the patients who completed remote monitoring during 4 weeks of follow-up.
• They noted cardiovascular complications in 10 patients and 8 patients, respectively, within 4 weeks of randomization.