title: Electroanatomic remodelling of the pulmonary veins associated with age.
abstract: OBJECTIVE
  Increasing age is a significant risk factor for developing atrial fibrillation (AF). Pulmonary vein (PV) triggers are critical in the mechanism of AF, but little is known of the substrate changes that occur within the PVs with ageing. Therefore, we sought to identify whether ageing is associated with electroanatomic changes within the pulmonary veins.
  
  
  RESULTS
  Twenty-five patients undergoing ablation for left-sided supraventricular tachycardia had high-density 3D electroanatomic maps of all four PVs created. Patients were divided into two groups: group 1 aged <50 years and group 2 aged >50 years. Mean-voltage (MV), % low-voltage (LV < 0.5 mV), conduction, signal complexity, and PV muscle sleeve length and diameter were assessed. Age was 33 ± 8 vs. 66 ± 8 years for groups 1 and 2, respectively (P < 0.001). Group 2 demonstrated: (i) lower MV within the PVs (1.66 ± 1.1 vs. 1.88 ± 1.1 mV, P < 0.001); (ii) increased % LV (5.0 vs. 1.1%, P < 0.001), and increased voltage heterogeneity within the PVs (65 ± 14 vs. 55 ± 8%, P < 0.05); (iii) regional and global conduction slowing in the PVs; and (iv) increased % complex signals within the PVs (1.4 vs. 0.4%, P = 0.009). There was no difference in PV sleeve length or diameter.
  
  
  CONCLUSIONS
  Increasing age is associated with PV electroanatomic changes characterized by a significant reduction in PV voltage, conduction slowing, and increasing signal complexity. These observations provide new insights into the potential mechanisms behind the increased prevalence of AF with advancing age.
authors.affiliation: The Department of Cardiology, Royal Melbourne Hospital, Melbourne, Australia.
authors.forename: Andrew W
authors.initials: AW
authors.lastname: Teh
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Kalman
authors.forename: Geoffrey
authors.initials: G
authors.lastname: Lee
authors.forename: Caroline
authors.initials: C
authors.lastname: Medi
authors.forename: Patrick M
authors.initials: PM
authors.lastname: Heck
authors.forename: Lian-Han
authors.initials: LH
authors.lastname: Ling
authors.forename: Saurabh
authors.initials: S
authors.lastname: Kumar
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Spence
authors.forename: Joseph B
authors.initials: JB
authors.lastname: Morton
authors.forename: Peter M
authors.initials: PM
authors.lastname: Kistler
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000375:Aging / Q000502:physiology*; D017115:Catheter Ablation; D005260:Female; D006325:Heart Atria / Q000503:physiopathology / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D011667:Pulmonary Veins / Q000033:anatomy & histology* / Q000503:physiopathology / Q000601:surgery; D013617:Tachycardia, Supraventricular / Q000503:physiopathology / Q000601:surgery; D016896:Treatment Outcome; D055815:Young Adult