Abstract Body (Do not enter title and authors here): Introduction: Atrial fibrillation (AF) serves both as a cause and a perpetuating factor in the progression of heart failure (HF). While left ventricular (LV) and left atrial (LA) dysfunction are recognized as prognostic markers, their relative prognostic contributions in patients with AF have not been fully elucidated.
Hypothesis: This study aimed to investigate the prognostic significance of LV and LA strain in patients with AF.
Methods: Among 921 patients with AF who performed echocardiography between 2009 and 2022, a total of 552 patients (mean age 69 ± 12 years, 39% female) were included after excluding those with significant valvular diseases, LVEF <50%, cardiac implantable devices, prior cardiac surgery, or inadequate image quality for strain analysis. The primary outcome was a composite of all-cause death and HF hospitalization. Patients were categorized into four groups based on LV global longitudinal strain (GLS) (<18.0%) and LA reservoir strain (LARS, <12.2%).
Results: During a median follow-up of 4.6 [2.4 – 7.2] years, 134 patients (24%) experienced the primary outcome, including 40 deaths (7%) and 94 HF hospitalization (17%). Patients with reduced LARS had worse outcomes compared to those with preserved LARS (log-rank p < 0.001) (Figure 1). In multivariate Cox regression analysis, patients with reduced both LARS and LV GLS showed (HR 1.69, 95% CI 1.10 – 2.62, p=0.018) the highest risk of adverse outcomes, even after adjusting for clinical and echocardiographic parameters (Figure 2). The group with reduced LARS but preserved LV GLS also demonstrated a higher event rate and a significant association in univariate analysis, though this did not remain significant in the multivariable model.
Conclusions: In patients with AF and preserved LVEF, combined impairment of LA and LV strain was independently associated with worse clinical outcomes. Although isolated LA dysfunction was not an independent predictor in multivariate analysis, its association with increased event rate highlights the potential prognostic role of atrial mechanics in this population. These findings suggest that incorporating LA and LV strain into routine assessment may enhance risk stratification in AF.