title: Left atrial wall thickness: anatomic aspects relevant to catheter ablation of atrial fibrillation.
abstract: BACKGROUND
  The success and complication rates of atrial fibrillation (AF) ablation may be related to regional differences in left atrial (LA) wall thickness. The purpose of this study was to investigate the transmural LA wall thickness in various regions.
  
  
  METHODS
  We measured LA wall thickness in 36 human heart specimens using calipers at three planes including left pulmonary veins (PVs) vestibule plane, right PVs vestibule plane and the middle plane between the two. In each plane, eight points were selected, including superior, middle and inferior levels at anterior and posterior wall, roof and bottom.
  
  
  RESULTS
  The anterior and posterior wall thickness displayed gradient from superior to inferior level (anterior wall: (2.73 ± 1.01) mm, (2.08 ± 0.91) mm and (1.54 ± 0.69) mm; posterior wall: (1.74 ± 0.68) mm, (1.48 ± 0.39) mm and (1.27 ± 0.42) mm). At the roof, LA wall thickness was thickest in middle plane ((2.01 ± 1.02) mm) and was thinnest in left PVs vestibule plane ((1.29 ± 0.41) mm). The posterior wall thickness in left PVs vestibule plane was thinner than in the other two planes (P < 0.05 - 0.001), and was thinner in right PVs vestibule plane than in middle plane (P < 0.01 - 0.001). Whereas in anterior wall, the wall thickness in left PVs vestibule plane was thicker than in middle and right PVs vestibule plane.
  
  
  CONCLUSIONS
  Significant variations exist for mean LA wall thickness at different regions which are often targeted during circumferential pulmonary venous ablation (CPVA). Appreciating these differences may have significant implications in catheter ablation of AF.
authors.affiliation: Department of Cardiology, Shanghai Chest Hospital Affiliated to Shanghai Jiao Tong University, Shanghai 200030, China.
authors.forename: Hong-Wei
authors.initials: HW
authors.lastname: Tan
authors.forename: Xin-Hua
authors.initials: XH
authors.lastname: Wang
authors.forename: Hai-Feng
authors.initials: HF
authors.lastname: Shi
authors.forename: Li
authors.initials: L
authors.lastname: Zhou
authors.forename: Jia-Ning
authors.initials: JN
authors.lastname: Gu
authors.forename: Xu
authors.initials: X
authors.lastname: Liu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000601:surgery*; D017115:Catheter Ablation; D005260:Female; D006325:Heart Atria / Q000033:anatomy & histology* / Q000601:surgery*; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D008875:Middle Aged