The Impact Of Age On The Electroanatomical Characteristics And Clinical Outcome After Catheter Ablation Of Patients With Atrial Fibrillation

Objective: Atrial Fibrillation (AF) is the most common arrhythmia, and more than 30% arrhythmia inpatient are for AF. With the increase of people's living qualities and the prolongation of average life length,the prevalence rate of coronary heart disease, heart failure and hypertension disease became much more, which cause the prevalence rate of AF to increase, and among those desease the age plays important role. However, there is limited evidence for the impact of age on AF atrial substrate and catheter ablation outcome.This study aimed to explore the impact of age on the recurrence after catheter ablation and the characteristics of electroanatomy in AF patients.Methods: 213 countious AF patients underwent circumferential pulmonary vein isolation (CPVI) guided by a CARTO mapping system were included in this study. They were divided into two groups according to AF types : Group I : paroxysmal AF (n=136), Group II: persistent AF (n=77), each group was divided into two subgroups based on ages: Group A: age >60 years old (n=130), Group B: age≤60 (n=83). The mean voltage and total activation time of the individual atria were obtained by using a CARTO mapping system before ablation. Six months of follow-up was conducted through the electrocardiogram and dynamic electrocardiogram after radiofrequency ablation; meanwhile, several parameters ,including gender, AF duration, left atrial (LA) diameter, and the underlying disease (hypertension,ect) were analyzed.Results: The younger patients had a significantly higher LA bipolar voltage (0.73±0.6 vs 0.51±0.36mV, respectively, p=0.002), less scar and less low voltage zone( LVZ), compared to the elder patients.The youger patients also demostrated an higher voltage and lower scar burden in group II, however,paroxysmal AF patients did not show the tendance of the LA bipolar voltage ,scar and LVZ burden changed with the ageConclusions: Age has a significant impact on the LA substrate properties of persistent AF, but not paroxysmal AF. The LA substrate properties,the voltage and scar burden,change with the age of persistent AF , whichfacilated the atrial fibrillation sustain.