Association Between Mean Left Atrial Voltage and Prior Ischemic Stroke in Atrial Fibrillation: A Single-Center Cross-Sectional Study.

Background/Objectives: Left atrial (LA) low-voltage area quantification is time-consuming and threshold-dependent. We investigated whether mean left atrial bipolar voltage, as a marker of atrial cardiomyopathy, is associated with prior ischemic stroke and compared its performance with low-voltage area percentage (LVA%). Methods: In this single-center retrospective cross-sectional study, 259 consecutive patients with atrial fibrillation (AF) undergoing radiofrequency catheter ablation were enrolled. Mean LA voltage was calculated as the arithmetic mean of all bipolar voltage points acquired during electroanatomic mapping. LVA% was defined as the proportion of LA surface area with voltage < 0.5 mV. Associations with prior ischemic stroke were assessed using Firth's penalized logistic regression. Results: The median age was 67 years and 31.7% were women. Twenty-nine patients (11.2%) had prior ischemic stroke. Patients with prior stroke had significantly lower mean LA voltage (0.5 [0.4-0.8] vs. 1.0 [0.6-1.3] mV, p < 0.001). After adjustment for CHA2DS2-VASc components, mean LA voltage remained independently associated with prior stroke (odds ratio 0.12, 95% confidence interval 0.03-0.38; p < 0.001). Mean LA voltage and LVA% showed comparable discrimination (area under the curve 0.743 vs. 0.717; p = 0.392), but adding mean LA voltage to the LVA%-only model improved model fit (likelihood ratio test p = 0.024). Conclusions: In this cross-sectional cohort, lower mean LA voltage was independently associated with prior ischemic stroke and may better reflect the extent of underlying atrial remodeling than LVA%.