Baseline remodeling-dependent changes in left atrial strain after catheter ablation for paroxysmal atrial fibrillation.

BACKGROUND

Left atrial (LA) mechanical function may change after catheter ablation for atrial fibrillation (AF); however, the determinants of follow-up LA function remain unclear. We aimed to characterize 6-month changes in LA strain and identify baseline determinants of follow-up LA strain after ablation for paroxysmal AF.

METHODS

This prospective study enrolled consecutive patients undergoing first-time pulmonary vein isolation for paroxysmal AF. Two-dimensional speckle-tracking echocardiography from apical four- and two-chamber views was performed at baseline and 6 months to assess LA reservoir strain (LASr) and contraction strain (LASct). Factors associated with 6-month LASr and ΔLASr (6-month minus baseline) were examined using multivariable linear regression.

RESULTS

Of 167 enrolled patients, 121 without structural heart disease and with analyzable echocardiograms in sinus rhythm at baseline and 6 months were included (67 ± 11 years; 68% men). LASr decreased (25.9 ± 7.9% to 23.1 ± 6.4%, p < 0.001) and LASct declined (11.8 ± 5.5% to 10.4 ± 4.8%, p = 0.007), while LA volume index (LAVI) was unchanged. Baseline LAVI was independently associated with 6-month LASr (standardized β = 0.32, p < 0.001), and higher baseline LAVI was associated with greater ΔLASr (standardized β = 0.33, p < 0.001). These associations were unchanged after adjustment for ablation modality (pulsed-field ablation vs thermal ablation).

CONCLUSIONS

Post-ablation changes in LA strain were continuously associated with baseline LA remodeling; lower baseline LAVI was independently associated with a less favorable change in LASr. Post-ablation LA function should be interpreted in conjunction with baseline remodeling.