Prognostic Value of Right Ventricular Performance and Left Atrial Mechanical Efficiency in Paroxysmal Atrial...

Background: Predicting atrial fibrillation (AF) recurrence remains a major clinical challenge, as conventional echocardiographic parameters often fail to capture the complex electro-mechanical substrate of the arrhythmia. The prognostic significance of right ventricular (RV) function and atrial mechanical-structural coupling in paroxysmal AF (PAF) remains underexplored. Methods: We prospectively enrolled patients with PAF in sinus rhythm undergoing comprehensive echocardiography. A wide range of conventional left-sided, right-sided, and novel coupling indices was assessed. Univariable analysis was performed to screen for potential AF recurrence predictors. Based on the initial findings, receiver operating characteristic (ROC) analysis was used to determine the optimal cutoff for RV fractional area change (RV FAC). Finally, multivariable logistic regression identified independent predictors of AF recurrence over a 12-month follow-up. Results: A total of 73 patients were included, of whom 31 (42.5%) experienced AF recurrence during 12-month follow-up. Conventional left atrial (LA) indices, including LA volume index (LAVI) and reservoir strain, showed no significant association with recurrence. In univariable analysis, RV FAC, LA contraction strain, and the novel LA contraction strain/LAVI ratio were all significant predictors. ROC analysis identified an RV FAC cutoff of 42.5%, with lower values associated with significantly higher recurrence rates. In multivariable analysis, lower RV systolic performance determined by RV FAC ≤ 42.5% emerged as a primary independent predictor of recurrence (p = 0.003), while the LA contraction strain/LAVI ratio demonstrated a strong trend towards significance (p = 0.076). Conclusions: In this exploratory study of patients with PAF, atrial mechanical-structural mismatch emerged as a primary marker of the arrhythmic substrate. Additionally, an exploratory signal suggested that a subclinical reduction in RV performance may also correlate with recurrence, though this warrants further investigation in larger cohorts.