Low voltage areas in paroxysmal atrial fibrillation: The prevalence, risk factors and impact on the effectiveness of catheter ablation

Int J Cardiol. 2018 Oct 15:269:139-144. doi: 10.1016/j.ijcard.2018.07.076. Epub 2018 Jul 19.

Abstract

Background: The prevalence, risk factors of left atrial low voltage areas (LVA) in paroxysmal atrial fibrillation (PAF) and the impact of LVA on the effectiveness of circumferential pulmonary vein isolation (CPVI) were not fully clarified.

Methods: One hundred fifty patients (mean age 64.7 years, 89 males) with PAF were consecutively enrolled to undergo CPVI. Prior to ablation a contact force sensing ablation catheter was utilized for LVA mapping in sinus rhythm. The patients were graded based on the proportion of LVA (LVA%): non LVA, mild (LVA% ≤ 10%), moderate (LVA% 10%-<20%) and severe (LVA% ≥ 20%), and were followed up for 12 months after initial CPVI.

Results: There were 56 in non LVA, 54 in mild LVA, 22 in moderate LVA and 18 in severe LVA. The prevalence of LVA was 62.7% in this PAF cohort, with the most frequent localization at anterior free wall (35.3%), PV antrum (22%) and septum (14.7%). Female gender (OR 3.634, 95% CI 1.704-7.751, P = 0.001) and left atrial surface area (LASA) (OR 1.024, 95% CI 1.000-1.048, P = 0.048) were risk factors of LVA. LVA% exceeding10% was associated with poor effectiveness of CPVI. LVA grade (HR 1.633, 95% CI 1.122-2.378, P = 0.011) was an independent predictor for AF recurrence after initial ablation.

Conclusions: LVA affected >60% of patients with PAF. Female gender and LASA were two risk factors of LVA. LVA grade was an independent predictor for AF recurrence following CPVI.

Keywords: Circumferential pulmonary isolation; Contact force sensing; Low voltage area; Paroxysmal atrial fibrillation; Voltage mapping.

MeSH terms

  • Aged
  • Atrial Fibrillation / diagnosis
  • Atrial Fibrillation / physiopathology*
  • Atrial Fibrillation / surgery*
  • Body Surface Potential Mapping / methods
  • Catheter Ablation / trends*
  • Cohort Studies
  • Female
  • Follow-Up Studies
  • Humans
  • Male
  • Middle Aged
  • Prevalence
  • Prospective Studies
  • Risk Factors
  • Treatment Outcome