Strain rate imaging for functional quantification of the left atrium: atrial deformation predicts the maintenance of sinus rhythm after catheter ablation of atrial fibrillation

The aim of the study was to investigate the atrial myocardial deformation properties using ultrasound strain rate (SR) imaging in patients after catheter ablation of atrial fibrillation (AF) and to compare its prognostic value in maintaining sinus rhythm.

A total of 118 patients with AF (74 paroxysmal AF, 44 persistent AF) underwent transthoracic echocardiography with Doppler-derived SR examinations before and after ablation as well as during 3 months of follow-up (FU). Peak SR and strain (S) were measured at each left atrium (LA) segment (septal, lateral, anterior, inferior) during systole (LAs) and at early (LAe) and late diastole (LAa). Clinical and echocardiographic parameters of patients with maintained sinus rhythm during FU were compared with those with recurrent AF and controls (n = 25 patients). Of 118 patients 82 (69%) showed stable sinus rhythm during FU. Atrial myocardial properties after catheter ablation differed significantly in patients with paroxysmal AF (SR-LAs 2.5 s⁻¹, S-LAs 30%, SR-LAa −2.2 s⁻¹) from patients with persistent AF (SR-LAs 2.3 s⁻¹, S-LAs 25%, SR-LAa −1.9 s⁻¹) and controls (SR-LAs 4.1 s⁻¹, S-LAs 88%, SR-LAa −2.9 s⁻¹) (P = 0.011). Best individual predictors of sinus rhythm maintenance were cut-off values of >2.25 s⁻¹ for septal and inferior SR-LAs and of >19.5% for inferior S-LAs (P < 0.001). LA deformation properties increased in patients with maintained sinus rhythm during FU in contrast to patients with recurrent AF (P = 0.001).

SR imaging enables the quantitative assessment of the LA function and can be considered as a potential marker of atrial reverse remodelling. Patients with higher atrial S and SR after catheter ablation appear to have a greater likelihood of maintenance of sinus rhythm. This may have further implications for the anticoagulation regime and the risk of cardioembolic complications.