Predictive Value of Left Atrial Strain Combined with Low-Voltage Substrate for Recurrence After Radiofrequency Catheter Ablation in Persistent Atrial Fibrillation

Background/Objectives: To evaluate associations of left atrial strain and low-voltage area (LVA) with recurrence after radiofrequency catheter ablation (RFCA) for persistent atrial fibrillation. Methods: This retrospective cohort included 66 patients undergoing first-time RFCA. Strain was measured before ablation and at 3 months, and voltage mapping quantified LVA. Recurrence after the 3-month blanking period was assessed during approximately 3 months of intermittent follow-up. Results: Recurrence was detected in 16 patients (24.2%). Preoperative left atrial reservoir strain (LASr) and contraction strain were lower in patients with recurrence. At 3 months, LASr-3mo and contraction strain remained lower, whereas LVA percentage was higher (11.50% vs. 3.00%; p < 0.001). LASr-3mo correlated negatively with LVA (r = −0.345; p = 0.005). In multivariable analyses, LASr-3mo (OR = 0.617; p < 0.001) and Delta LASr (OR = 0.461; p < 0.001) were inversely associated with recurrence, whereas LVA was positively associated (OR = 1.069; p = 0.044). The LASr-3mo plus LVA model showed promising apparent discrimination (apparent AUC = 0.923; bootstrap-corrected AUC = 0.913). Conclusions: LASr-3mo may contribute to postoperative risk reassessment. LVA remains an exploratory observational marker because voltage mapping influenced treatment selection. The cohort-derived 4.5% LVA cut-off and model performance require prospective external validation using standardized ablation protocols.