Predictors of atrial high-rate episodes detection and increase in patients with cardiac implantable electronic devices: a single centre study using demographic and echocardiographic parameters

Atrial high-rate episodes (AHRE) in patients with cardiac implantable electronic devices (CIEDs) have gained increasing interest since recent evidence on their role as a surrogate of atrial fibrillation, especially in patients at high cardioembolic risk. The common definition of AHRE corresponds to atrial activity with a rate > 175/min lasting more than 5 minutes (1), but it can varies also according to devices. Factors determining their onset and trend over time are still not well delineated. (2).

The aim of this study was to analyse the predictive role of commonly used echocardiographic and demographic data on AHRE detection and increase over time in a single centre population.

From January 2023 to September 2024, we collected data from 112 patients during a first routinary scheduled CIED follow up. Patients with history of atrial fibrillation were excluded. We divided patients according to detection or not detection of AHRE during the first control and considered a following 12-month device check in patients with detected AHRE. We analysed the predictive role of common demographic and echocardiographic data (including strain parameters) in relation to AHRE detection during the first visit and to AHRE increase after 12 months.

In patients with AHRE detection, history of AV block previous to CIED implant was significantly more frequent together with increased atrial pacing, lower peak atrial longitudinal strain (PALS) and peak atrial contraction strain (PACS). The univariate analysis identified PACS, PALS, atrial pacing (Ap) percentage, body mass index (BMI), presence of atrioventricular (AV) block at implant, as predictors of AHRE detection. PACS, PALS and Ap Percentage were the only independent predictors of AHRE detection at the first follow up. ROC curves showed a good performance of atrial pacing percentage with an AUC 0,88. In patients with AHRE identified at first follow up, PACS and betablocker use resulted independent predictors of AHRE increase after 12 months.

In this study we demonstrated that reduced PACS and PALS together with increased atrial pacing are independent predictors of AHRE recorded during the 12 months before CIED check. PACS and betablockers are negatively associated with AHRE increase in the 12 months following AHRE detection. These results highlight that left atrial function and sources of atrial remodelling such as atrial pacing, together with attempts of rate control, influence the trend of AHRE. These characteristics confirm a point in common with atrial fibrillation which could help in defining preventive strategies.

Baseline charachteristics of patients