Left atrial contraction strain as a predictor of device-detected atrial fibrillation in patients with heart failure with reduced ejection fraction

Abstract Atrial fibrillation (AF) is the most common atrial arrhythmia in patients with heart failure (HF) and is associated with left atrial (LA) remodeling. Left atrial strain parameters are sensitive and specific markers of early LA dysfunction. We aimed to identify predictors of new-onset atrial fibrillation (NOAF) in patients with heart failure with reduced ejection fraction (HFrEF) treated with implantable cardioverter-defibrillator (ICD) or cardiac resynchronization therapy (CRT). Our study population comprised 88 patients with HFrEF (left ventricular ejection fraction ≤ 40%) undergoing ICD or CRT implantation. All patients underwent transthoracic echocardiography and electrocardiography at baseline and after 12 months. NOAF episodes were identified through device interrogation. NOAF was detected in 15 patients (17%). NOAF group demonstrated lower left atrial reservoir (LASr) and contraction strain (LASct), reduced LA emptying fraction (LAEF), and increased LA stiffness index (LASI, all p < 0.001). In addition, NOAF patients had longer PQ intervals ( p = 0.03) and higher NT-proBNP concentrations ( p = 0.004). In univariable logistic regression analysis, lower LASr (OR 0.802), LASct (OR 0.768), and higher LASI (OR 2.218) were significantly associated with NOAF (all p < 0.001). LASct showed the highest discriminative performance for NOAF prediction (AUC 0.829), exceeding LASr (AUC 0.789) and other echocardiographic parameters. LASr, LASct, LAEF and LASI were strongly interrelated (|rho| 0.75–0.90), and LASct stayed associated with NOAF after adjustment for LV global longitudinal strain, LVEF and E/e′. In this exploratory dataset, impaired LA mechanics were associated with device-detected AF, and LASct showed the best discrimination of the parameters tested. The small number of events, the strong intercorrelation between LA functional indices and the lack of external validation prevent firm conclusions about independent or incremental prognostic value.