Prognostic value of left atrial stiffness index for incident heart failure in paroxysmal atrial fibrillation: a prospective cohort study

Aims Approximately 20-30% of paroxysmal atrial fibrillation (PAF) may progress into heart failure (HF). Identifying specific PAF characteristics predisposing to HF is crucial for enabling precise interventions. Methods and results A cross-sectional study first evaluated subclinical cardiac dysfunction in PAF (n=142) versus controls (n=63), employing echocardiography to assess noninvasive left ventricular myocardial work (LVMW), left atrial (LA) remodeling, and LA strain. Subsequently, a prospective cohort study within the PAF group identified echocardiography predictors for incident HF using multivariable logistic regression analysis (adjusted for confounding; Stata 15.0, R 4.1). Compared with the controls, PAF had significantly elevated global wasted work (GWW), impaired global work efficiency (GWE), increased peak strain dispersion (PSD), enlarged LA volume index (LAVI), decreased LA ejection fraction (LAEF), impaired LA strain and increased LA stiffness index (LASI) (0.69±0.51vs0.41±0.18, p<0.001). Increased LASI was correlated with increased PSD, impaired E/e’, enlarged LAVImin, decreased LAEF and impaired LA strain in PAF. During a median follow-up of 40.5 months, incident HF occurred in 9.86% in PAF participants. Increased LASI (OR:16.4,95%CI 1.44-186.72, p=0.02) was significantly associated with incident HF, with a value greater than 1.24 maximizing predictive accuracy (AUC=0.77, 95%CI 0.61-0.93) in non-alation subgroup. Conclusions Subclinical cardiac dysfunction of PAF includes elevated GWW, reduced GWE, increased LASI, and impaired LA strain and cardiac dysfunction of PAF may originate in LA remodeling and dysfunction. Increased LASI could predict incident HF and PAF with LASI greater than 1.24 should be strongly proposed for early sinus rhythm restoring strategy to prevent incident HF.