Left atrial remodeling and voltage-guided ablation outcome in persistent atrial fibrillation patients over 75 years of age

Background

The prevalence of atrial fibrillation (AF) increases with age. The improvement in ablation techniques has widened the indications, particularly in elderly patients. Data on LA remodeling and low-voltage zone (LVZ) extent in this subgroup are scarce.

Objective

We assessed the left atrial (LA) bipolar voltage, LVZ extent, and efficacy of voltage-guided ablation in a cohort of patients with persistent AF according to age.

Methods

Three hundred fifty-three patients with persistent AF undergoing a first voltage-guided ablation procedure were enrolled and divided into 2 groups: those <75 years of age (n=286) and those ≥75 years of age (n=67). LA voltage maps were obtained in sinus rhythm. LVZ was defined as <0.5 mV. A propensity score–matching analysis was used to assess the impact of age on LA remodeling.

Results

The LA bipolar voltage was lower (P<.01) in elderly patients. LVZs were found in 67% of elderly patients and 30% of younger patients (P<.01), especially in mild (P<.01) and moderate (P<.01) LVZs. After propensity score matching, these differences were no longer noticeable. Pulmonary vein isolation alone was performed in 33% of elderly patients and 70% of patients <75 years of age (P<.01). Female sex (P<.001), age ≥ 75 years (P=.042), estimated glomerular filtration rate (P=.009), and LA volume index (P<.001) were predictive of LVZ presence. After 36 months of follow-up, the AF-free survival rate after a single procedure was similar between the 2 groups.

Conclusion

Patients >75 years of age with persistent AF display increased LA substrate remodeling than do younger patients. LA scar did not seem to negatively affect the results of substrate-guided ablation, and the complication rate was low.