title: Histopathological features of the resected left atrial appendage as predictors of recurrence after surgery for atrial fibrillation in valvular heart disease.
abstract: BACKGROUND
  A histopathological assessment of left atrial appendages (LAA) resected during surgical treatment for atrial fibrillation (AF) was made, with the aim of improving the prediction of postoperative AF recurrence.
  
  
  RESULTS
  This clinicopathological study involved 57 surgical cases of valvular AF and 34 age- and sex-matched control autopsy cases with a history of sinus rhythm. LAA from the cases with valvular AF showed greater hypertrophy of cardiomyocytes (p<0.0001), greater nuclear enlargement (p<0.0001), more bizarre nuclei (BN; p<0.0001), and more intercellular fibrosis (ICF; p<0.001). Partial disarray of cardiomyocytes and fatty infiltration were recognized in both the AF and control groups. Thirty-seven cases had maintained sinus rhythm after surgery from 7 months to 10 years. AF recurred within a month of surgery in 17 and after a month in 3; there was no significant difference in histopathological features between them. These 20 cases had more cellular hypertrophy (p<0.025), nuclear enlargement (p<0.025), BN (p<0.01), and ICF (p<0.025) than those who maintained sinus rhythm after surgery.
  
  
  CONCLUSIONS
  The histopathological findings for LAA reflected the underlying valvular diseases; however, the most reliable predictors of postoperative AF recurrence were hypertrophy of cardiomyocytes, bizarre shaped nuclei, and extensive ICF.
authors.affiliation: Nippon Medical School, Department of Pathology, Toranomon Hospital, Tokyo, Japan.
authors.forename: Tsunenori
authors.initials: T
authors.lastname: Saito
authors.forename: Koichi
authors.initials: K
authors.lastname: Tamura
authors.forename: Daisuke
authors.initials: D
authors.lastname: Uchida
authors.forename: Tomonari
authors.initials: T
authors.lastname: Saito
authors.forename: Mayuko
authors.initials: M
authors.lastname: Togashi
authors.forename: Takashi
authors.initials: T
authors.lastname: Nitta
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Sugisaki
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D020517:Atrial Appendage / Q000473:pathology* / Q000601:surgery; D001281:Atrial Fibrillation / Q000209:etiology / Q000473:pathology* / Q000601:surgery*; D001344:Autopsy; D016022:Case-Control Studies; D005260:Female; D006325:Heart Atria / Q000473:pathology* / Q000601:surgery; D006349:Heart Valve Diseases / Q000150:complications / Q000473:pathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D032383:Myocytes, Cardiac / Q000473:pathology; D011237:Predictive Value of Tests; D012008:Recurrence