The diagnostic value of left atrial stiffness for heart failure with preserved ejection fraction in patients with paroxysmal atrial fibrillation.

AIMS: Left atrial (LA) function is impaired in both atrial fibrillation (AF) and heart failure with preserved ejection fraction (HFpEF). Diagnosing HFpEF remains challenging, especially in AF patients. This study aims to evaluate whether LA stiffness (LAS) can facilitate the diagnosis of HFpEF in patients with paroxysmal atrial fibrillation (pxAF). METHODS AND RESULTS: A total of 187 pxAF patients were enrolled in the discovery cohort and underwent baseline transthoracic echocardiography (TTE). LAS was measured in all patients, and HFpEF was ascertained based on the H2FPEF score (44 high-probability of HFpEF [hp-HFpEF], 143 low-probability of HFpEF [lp-HFpEF]). The left ventricular diastolic function and LA function were significantly altered in the hp-HFpEF group compared to the lp-HFpEF group. Among all echocardiographic indices, the ratio of E/MVE’ to 3D LAEF as a surrogate of LAS showed the greatest diagnostic performance in distinguishing hp-HFpEF from lp-HFpEF in pxAF patients (AUC = 0.862, 95% CI 0.801–0.922, p < 0.001), with an optimal cutoff value of 0.27. Combining MVE’ and LAS revealed the highest diagnostic efficiency (LR + 12.18) compared to any single variable. The discriminatory value of LAS with MVE’ was further verified in the validation cohort with an LR + of 7.18. CONCLUSION: LAS analyzed by conventional echocardiography combined with MVE’ is a non-invasive, decision-support approach for discriminating hp-HFpEF from lp-HFpEF in pxAF patients. The clinical trial registration number: ClinicalTrials.gov NCT05266144.