A wait-and-see approach was noninferior to early cardioversion for achieving sinus rhythm at 4 weeks (91% vs 94%; difference -2.9 percentage points; P=0.005 for noninferiority).
RCT (n=437)
Open-label
randomized
Yes
Does a wait-and-see approach (delayed cardioversion) achieve noninferior rates of sinus rhythm at 4 weeks compared to early cardioversion in patients with recent-onset symptomatic atrial fibrillation?
A wait-and-see approach with delayed cardioversion is noninferior to early cardioversion for achieving sinus rhythm at 4 weeks in recent-onset atrial fibrillation, allowing the majority of patients to spontaneously convert and avoid cardioversion.
Effect estimate: Difference -2.9 percentage points (95% CI -8.2 to 2.2)
Absolute Event Rate: 91% vs 94%
p-value: p=0.005 for noninferiority
BACKGROUND: Patients with recent-onset atrial fibrillation commonly undergo immediate restoration of sinus rhythm by pharmacologic or electrical cardioversion. However, whether immediate restoration of sinus rhythm is necessary is not known, since atrial fibrillation often terminates spontaneously. METHODS: In a multicenter, randomized, open-label, noninferiority trial, we randomly assigned patients with hemodynamically stable, recent-onset (<36 hours), symptomatic atrial fibrillation in the emergency department to be treated with a wait-and-see approach (delayed-cardioversion group) or early cardioversion. The wait-and-see approach involved initial treatment with rate-control medication only and delayed cardioversion if the atrial fibrillation did not resolve within 48 hours. The primary end point was the presence of sinus rhythm at 4 weeks. Noninferiority would be shown if the lower limit of the 95% confidence interval for the between-group difference in the primary end point in percentage points was more than -10. RESULTS: The presence of sinus rhythm at 4 weeks occurred in 193 of 212 patients (91%) in the delayed-cardioversion group and in 202 of 215 (94%) in the early-cardioversion group (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, conversion to sinus rhythm within 48 hours occurred spontaneously in 150 of 218 patients (69%) and after delayed cardioversion in 61 patients (28%). In the early-cardioversion group, conversion to sinus rhythm occurred spontaneously before the initiation of cardioversion in 36 of 219 patients (16%) and after cardioversion in 171 patients (78%). Among the patients who completed remote monitoring during 4 weeks of follow-up, a recurrence of atrial fibrillation occurred in 49 of 164 patients (30%) in the delayed-cardioversion group and in 50 of 171 (29%) in the early-cardioversion group. Within 4 weeks after randomization, cardiovascular complications occurred in 10 patients and 8 patients, respectively. CONCLUSIONS: In patients presenting to the emergency department with recent-onset, symptomatic atrial fibrillation, a wait-and-see approach was noninferior to early cardioversion in achieving a return to sinus rhythm at 4 weeks. (Funded by the Netherlands Organization for Health Research and Development and others; RACE 7 ACWAS ClinicalTrials.gov number, NCT02248753.).
Pluymaekers et al. (Mon,) conducted a rct in Recent-onset atrial fibrillation (n=437). Wait-and-see approach (delayed cardioversion) vs. Early cardioversion was evaluated on Presence of sinus rhythm at 4 weeks (Difference -2.9 percentage points, 95% CI -8.2 to 2.2, p=0.005 for noninferiority). A wait-and-see approach was noninferior to early cardioversion for achieving sinus rhythm at 4 weeks (91% vs 94%; difference -2.9 percentage points; P=0.005 for noninferiority).