Impaired left atrial strain as a predictor of bradyarrhythmias and clinical outcomes following TAVI

Abstract

Transcatheter aortic valve implantation (TAVI) is the preferred treatment for elderly patients with symptomatic severe aortic stenosis (SAS). Left atrial (LA) dysfunction is an established prognostic marker in various clinical settings. This study aimed to evaluate the correlation between LA function, assessed by strain parameters, and the incidence of permanent pacemaker (PPM) implantation or major adverse cardiovascular events (MACE) in patients with SAS undergoing TAVI. A total of 157 patients with SAS treated with TAVI between January 2019 and April 2021 were screened. Patients with pre-existing cardiac implanted devices or permanent atrial fibrillation were excluded. The mean follow-up was 24 ± 13 months. LA function was assessed using transthoracic echocardiography (TTE) by measuring three strain parameters: LA reservoir strain (LASr), LA conduit strain (LASct), and LA contractile strain (LAScd). The study endpoints were the association between these strain parameters and the occurrence of PPM implantation or MACE during follow-up. Ninety-nine patients were included in the analysis. During follow-up, 43 patients experienced MACE. Mean values for LASr, LASct, and LAScd were 29.5 ± 12.7%, -18.7 ± 11.0%, and - 18.5 ± 7.3%, respectively. Patients requiring PPM implantation showed significantly reduced LA strain values compared to those who did not (LASr: 13.1% vs. 33.2%; LASct: -10.1% vs. -21.0%; LAScd: -6.7% vs. -21.6%, p < 0.001). Similarly, patients who developed MACE had reduced strain values compared to those without events (LASr: 21.9% vs. 35.4%; LASct: -14.3% vs. -21.8%; LAScd: -9.9% vs. -25.5%, p < 0.001). Pre-TAVI LA dysfunction, assessed through LA strain, is closely associated with increased risk of PPM implantation and MACE.

Keywords: Atrial fibrillation; Left atrial strain; Pacemaker implantation; Severe aortic stenosis; Transcatheter aortic valve implantation.