Predictors of Low Voltage Zone and Sex Differences in Low Voltage Zone Distribution in Patients with Atrial Fibrillation

Background: Previous studies have revealed the left atrial (LA) low voltage zone (LVZ) are tightly linked to the recurrence of atrial fibrillation (AF). Furthermore ablation that targets the LA LVZ can improve patient prognosis. The aim of this study was to identify potential clinical predictors of the LA LVZ, to investigate possible sex differences in the distribution of LA LVZ, and to examine the relationship between LA LVZ and AF recurrence. Methods: A total of 108 patients who underwent AF catheter ablation and LA high-density electro-anatomic mapping were enrolled in the study. Of these, 56 patients with LA LVZ ≥5% were assigned to the LVZ group, while the remaining 52 patients with LA LVZ <5% were assigned to the non-LVZ group. Clinical characteristics and laboratory results for all patients were collected and compared between the two groups. Results: Multivariate logistic regression analysis revealed that persistent AF (odds ratio [OR] = 4.563, 95% confidence interval [CI]: 1.194–17.431, p = 0.026), left atrial volume (LAV, OR = 1.030, 95% CI: 1.001–1.061, p = 0.044) and brain natriuretic peptide (BNP, OR = 1.010, 95% CI: 1.002–1.019, p = 0.015) were independent predictors for the presence of LA LVZ. In addition, female sex (OR = 7.161, 95% CI: 1.518–33.792, p = 0.013), LAV (OR = 1.028, 95% CI: 1.002–1.055, p = 0.035) and BNP (OR = 1.009, 95% CI: 1.001–1.016, p = 0.018) were independent predictors of severe LA LVZ (LA LVZ >20%). The extent of LVZ was significantly greater in females than in males (32.8% ± 15.5% vs. 23.5% ± 12.7%, p = 0.021), especially in the anterior (34.5% ± 16.7% vs. 20.0% ± 16.4%, p = 0.003) and septal (44.9% ± 17.1% vs. 29.0% ± 18.9%, p = 0.004) walls. During follow-up, AF recurrence was significantly higher in patients with LA LVZ than in those without LA LVZ (31.3% vs. 12.8%, respectively, p = 0.023). Conclusions: In this study cohort, persistent AF, LAV and BNP were independent predictors of LA LVZ. Furthermore, female sex, LAV and BNP were independent predictors of severe LA LVZ. Females had a significantly greater extent of LVZ than males, especially in the anterior and septal walls. Patients with LA LVZ had a higher risk of recurrent AF.