B-po05-082 sex-related differences in atrial substrate in patients undergoing pulmonary vein isolation: an age and atrial fibrillation-type matched analysis

Recent data have shown increased rates of atrial fibrillation (AF) recurrence among females compared to males after pulmonary vein isolation (PVI). Whether these differences in outcomes are due to increased age, prevalence of persistent AF or of abnormal atrial substrate among females at time of ablation is unclear. To compare left atrial (LA) scar burden and location as determined by electroanatomic mapping between females and males undergoing PVI. Out of 150 pts undergoing PVI, 46 pts (mean age 67 ± 9 yrs) were matched by sex, age category and AF-type (paroxysmal vs persistent) and included in the study. LA voltage maps were performed in sinus rhythm or atrial pacing using a 1 mm multi-electrode catheter (Pentaray). LA scar was defined as bipolar voltage ≤ 0.2 mV. The LA was divided into 6 regions: roof, septum, anterior wall, posterior wall, lateral wall and floor. Total scar burden was calculated for each region and the entire LA. Compared to males, females had a significantly higher LA scar burden (median 16.8 [IQR 2.5 - 35.3]% versus 1.2 [0 - 3.8]%; P <0.01). In 16 females with LA scar (burden ≥ 5%), burden was highest in the anterior wall (median 34 [16 - 73]%) and roof (median 29 [5 - 73]%). In 4 males with LA scar, burden was highest in the anterior wall (median 29 [7 - 64]%) and lateral wall (median 20 [4 - 57]%). After adjustment for age, AF-type and comorbidities, female sex was independently associated with LA scar (aOR 8.39; 95% CI [1.79 - 39.4]). In this matched analysis, females had significantly higher LA scar burden than males. An increased prevalence of atrial cardiopathy among females undergoing PVI may contribute to higher rates of AF recurrence.