Left atrial function after atrial fibrillation ablation with pulsed field vs radiofrequency energy: A comparative study.

BACKGROUND

The impact of pulmonary vein isolation (PVI) using pulsed field ablation (PFA) on left atrial (LA) function remains incompletely understood.

OBJECTIVE

To compare the effects of PVI performed with PFA vs radiofrequency ablation (RFA) on LA mechanical function in patients with paroxysmal atrial fibrillation (PAF), using serial echocardiographic strain analysis.

METHODS

In this prospective, single-center study, patients undergoing a first-time PVI for PAF with either RFA or PFA were included. All participants underwent transthoracic echocardiography with 2-dimensional speckle tracking analysis at 3 time points: at baseline (immediately before ablation), in the acute phase (immediately after ablation), and in the chronic phase (3 months post-ablation). LA reservoir strain (LASr) and LA contraction strain (LASct) were assessed as primary parameters of LA mechanical function.

RESULTS

A total of 59 patients were analyzed (RFA: 28; PFA: 31). In the PFA group, LASr and LASct decreased significantly in the acute phase (LASr: 26.5 ± 5.8% to 22.9 ± 6.6%, P = .010; LASct: 12.2 ± 3.6% to 8.6 ± 3.1%, P < .001). At 3-month follow-up, LASr had recovered to baseline levels (25.8 ± 7.9%, P = .531), while LASct remained significantly reduced (10.9 ± 4.3%, P = .031). In contrast, no significant changes in LASr or LASct were observed in the RFA group at any time point.

CONCLUSION

PVI using PFA is associated with acute LA stunning, with persistent impairment in contractile function at 3 months despite recovery of reservoir function. These findings suggest subtle, lasting alterations in atrial mechanics not observed with RFA.