Echocardiographic predictors of undiagnosed heart failure with preserved ejection fraction in hospitalized atrial fibrillation patients with dyspnea

The aim was to evaluate the prevalence and echocardiographic predictors of previously undiagnosed heart failure with preserved ejection fraction (HFpEF) in patients with atrial fibrillation (AF) and chronic dyspnea. Material and methods. This prospective observational study included 85 patients hospitalized for cardioversion with paroxysmal or persistent AF and chronic dyspnea. All participants underwent transthoracic speckle-tracking echocardiography of left atrial longitudinal strain (LAS). HFpEF probability was assessed using the HFA-PEFF algorithm. Dynamic follow-up of diastolic function was performed at three predefined time points: during AF paroxysm, 24 hours post-cardioversion, and one-month post-cardioversion. Results. High probability of HFpEF was identified in 78.7% of patients (67 out of 85). These patients exhibited significantly higher NT-proBNP levels, greater CHA₂DS₂-VASc score, as well as more impaired LAS parameters and elevated left atrial stiffness index compared to low-intermediate HFpEF probability groups. At one-month follow-up after cardioversion ( n = 55), while NT-proBNP levels significantly declined, overall HFpEF probability remained unchanged. Left atrial stiffness index demonstrated the strongest independent predictive value in verifying high probability HFpEF, with remarkable discriminative capacity both during AF (OR = 34.5; 95% CI 2.5 – 478.7) and after sinus rhythm restoration (OR = 193.1; 95% CI 7.3 – 1,207). Conclusion. This study reveals high prevalence of undiagnosed HFpEF among AF patients undergoing cardioversion, with disease probability persisting despite rhythm control during one-month follow-up. The left atrial stiffness index is as a valuable diagnostic marker for HFpEF detection in this population, potentially enhancing standard HFA-PEFF algorithm.