Abstract
BACKGROUNDS: Alterations in the atrial structure and function associated with aging result in electric remodeling of the left atrium (LA) in patients with persistent atrial fibrillation (AF). We performed this study to evaluate the influence of age on electric remodeling as assessed by the extent of complex fractionated atrial electrograms (CFAEs) in the LA. METHODS: A total of 122 patients (mean age, 55.9 ± 10.4 years; range, 31-79; 106 males) who underwent catheter ablation for drug-refractory persistent AF were included in the study. The extent of CFAE was measured by CFAE area and its index (CFAE area/LA surface area × 100) using three-dimensional automated software of NavX system. RESULTS: The mean value of CFAE extent was significantly different among age groups; the CFAE area decreased significantly with increasing age (30 seconds [43.2 ± 14.5 mm(2)] vs 40 seconds [28.6 ± 6.0 mm(2)] vs 50 seconds [22.8 ± 3.4 mm(2)] vs 60 seconds [15.3 ± 2.6 mm(2)] vs 70 seconds [10.3 ± 3.2 mm(2)]; P = .010). A similar significant decrease was observed in the CFAE area index (30 seconds [22.9 ± 7.4] vs 40 seconds [14.9 ± 3.4] vs 50 seconds [10.4 ± 1.6] vs 60 seconds [6.9 ± 1.2] vs 70 seconds [4.6 ± 1.4]; P = .002). Age had a significantly negative correlation with the CFAE area (r = -0.322, P < .001) and CFAE area index (r = -0.357, P < .001). CONCLUSIONS: Increasing age is associated with electric remodeling in the LA characterized by a decrease in the extent of CFAE area and its index.