title: The double-orifice tricuspid valve: a review.
abstract: OBJECTIVE
  Duplication of an atrioventricular valve is a rare congenital anomaly, with only single cases of double-orifice tricuspid valves (DOTV) having been identified. Because of its rarity, the clinical spectrum of this entity remains obscure.
  
  
  METHODS
  A literature search was conducted using databases and search engines. In addition, the reference sections of all relevant articles were searched to identify additional cases. All cases reported until March 2006 were included.
  
  
  RESULTS
  In total, 22 cases of DOTV were identified. The mean patient age was 21 years, and there was a male predominance. Autopsy was the leading mode of detection, followed by surgery and echocardiography. In cases where the functional status of the DOTV was specifically mentioned, pure regurgitation was found in 62.5%, and combined stenosis and regurgitation in 25%. In 12.5% of cases the valve function was normal. Additional congenital malformations were present in (72.7%) of cases (n = 16).
  
  
  CONCLUSIONS
  The DOTV is a very rare congenital heart defect. The isolated occurrence of this condition seems extremely rare, and in most cases it is associated with other congenital cardiac malformations that determine patient outcome.
authors.affiliation: Department of Cardiology and Angiology, Hannover Medical School, Hannover, Germany. otutarel@hotmail.com
authors.forename: Oktay
authors.initials: O
authors.lastname: Tutarel
authors.forename: Mechthild
authors.initials: M
authors.lastname: Westhoff-Bleck
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D012727:Sex Characteristics; D014261:Tricuspid Valve / Q000002:abnormalities*; D014262:Tricuspid Valve Insufficiency / Q000209:etiology; D014264:Tricuspid Valve Stenosis / Q000209:etiology