Left atrial reservoir strain predicts recurrence of atrial fibrillation after electrical cardioversion
TL;DR
LA reservoir strain < 17% was predictive of AF recurrence and suggests that additional follow-up and AF management may be needed.
Abstract
Electrical cardioversion (ECV) for persistent atrial fibrillation (AF) is a method used to restore sinus rhythm (SR) to reduce symptoms and improve quality of life. However, AF recurrence is common, and there is a need for clinically useful predictors. We examined whether left atrial (LA) reservoir strain could predict AF recurrence 4 weeks after ECV for persistent AF. We included 200 adults with persistent AF who were referred for ECV in an observational, cohort study. We performed transthoracic echocardiography using Automated Function Imaging to assess LA reservoir strain in participants with SR 3 to 6 hours after ECV for persistent AF. Participants recorded at-home ECGs twice daily and, if symptomatic, for 28 days after the ECV to detect AF recurrence. A total of 140 of 164 participants who underwent ECV for persistent AF were successfully cardioverted and had echocardiography assessable for LA strain. The mean age was 66.3 ± 8.8 years, and 80% were men. A total of 72 participants (51.4 %) had an AF recurrence during the observation period. LA reservoir strain was significantly lower in participants with AF recurrence than in those who maintained SR (13.5 % ± 4.4 vs. 15.7 % ± 5.7, p = 0.01). There was a non-linear association between LA reservoir strain and AF recurrence (p = 0.036). The area under the curve was 0.63 (95% CI 0.56-0.70) in a univariate receiver operating characteristic curve, and the optimal cutoff for LA reservoir strain was 17% (Youden index). A Kaplan-Meier plot showed a significant difference in time to AF recurrence between participants with LA reservoir strain < 17% and those with LA reservoir strain ≥ 17% (log-rank, p = 0.016). Participants with LA reservoir strain < 17 % had 50% higher hazard of AF recurrence compared to those with LA reservoir strain ≥ 17% (Hazard Ratio 1.5, 95% CI 1.04-2.04, p = 0.03). LA reservoir strain was significantly lower in participants with AF recurrence than in those who maintained SR four weeks after ECV for persistent AF. LA reservoir strain < 17% was predictive of AF recurrence and suggests that additional follow-up and AF management may be needed.Box plot of LA reservoir strainKM plot by LA reservoir strain of 17 %