Left atrial reservoir function predicts atrial fibrillation recurrence after catheter ablation: a two-dimensional speckle strain study

Abstract

Background: Predictors of atrial fibrillation (AF) recurrence after catheter ablation (CA) are not fully defined. We hypothesized that 2D left atrial (LA) regional strain maps would help identify abnormal atrial substrate that increases susceptibility to AF recurrence post-CA.

Methods and results: Sixty-three patients (63 ± 10 years, 60% male) underwent CA for symptomatic paroxysmal (75%) or persistent (25%) AF. Baseline LA mechanical function determined using speckle tracking echocardiography was compared between those with AF recurrence (AFR) and no recurrence post-CA. Bi-dimensional global and regional maps of LA wall velocity, strain, and strain rate (SR) were obtained during end ejection and early diastole. After 18 ± 12 months of follow-up, 34 patients were free of AFR post-CA. There were no differences in clinical characteristics, LA and LV volumes, and Doppler estimates of LV diastolic function and filling pressures at baseline between patients with recurrent AF and those that maintained sinus rhythm. However, the LA emptying fraction (55 ± 17% vs. 64 ± 14%, p = 0.04), global and regional systolic and diastolic strains, SR, and velocities were reduced in patients with recurrent AF. There was marked attenuation of peak LA lateral wall longitudinal strain (LS; 11 ± 7% vs. 20 ± 14%, p = 0.007) and SR (0.9 ± 0.4 vs.1.3 ± 0.6 s(-1), p = 0.01). Multivariate analysis revealed lateral wall LS (odds ratio = 1.15, 95% CI = 1.02-1.28, p = 0.01) as an independent predictor of AFR.

Conclusions: Regional LA lateral wall LS is a pre-procedural determinant of AFR in patients undergoing CA, independent of LA enlargement. Characterization of atrial myocardial tissue properties by speckle tracking echo may aid the appropriate selection of adjunctive strategies and prognostication of patients undergoing CA.

Figures

Fig. 1

Assessment of LA strain by speckle tracking echocardiography. Left atrial wall was tracked in apical four-chamber view using speckle tracking echocardiography. (a, b) Tracking of LA wall and corresponding velocity vectors in a patient without recurrence and with recurrence of AF. (c, d) Corresponding global strains. (e, f) Global SR in the two patients. Note the diminished global strain and SR in the patient who had recurrence of AF. LA left atrial; AF atrial fibrillation; AFR atrial fibrillation recurrence; NR no recurrence group

Fig. 2

Box plot showing the differences in LA lateral wall LS as an independent predictor of recurrence

Fig. 3

ROC curve for the prognostic utility of LA lateral wall LS