title: Comparison of valve structure, valve weight, and severity of the valve obstruction in 1849 patients having isolated aortic valve replacement for aortic valve stenosis (with or without associated aortic regurgitation) studied at 3 different medical centers in 2 different time periods.
abstract: BACKGROUND
  Aortic valve replacement (AVR) for patients with aortic stenosis (AS) has now been available for 45 years. During this period, indications for the procedure have changed.
  
  
  RESULTS
  Operatively excised stenotic aortic valves (with or without associated aortic regurgitation and without associated mitral valve disease) from 3 different medical centers (National Institutes of Health, Georgetown University Medical Center, and Baylor University Medical Center) were examined during 2 different time periods by the same physician to compare aortic valve structure, valve weight, age at operation, preoperative transvalvular peak pressure gradient, calculated aortic valve area, and whether simultaneous coronary artery bypass grafting (CABG) was performed. Compared with the first 3 decades (1961-1990) of AVR, patients having this operation during the fourth and fifth decades (1991-2004) had a lower frequency of congenitally malformed aortic valves, a higher frequency of tricuspid aortic valves, an older age, valves of lighter weight and lower transvalvular peak pressure gradients, and more often simultaneous CABG.
  
  
  CONCLUSIONS
  Although patients having isolated AVR for AS in the present and last decade were older than in the first 3 decades of valve replacement surgery, congenitally malformed aortic valves continue to be more common than tricuspid aortic valves, but the degree of AS and therefore, valve weight was significantly lower than in the earlier decades.
authors.affiliation: Baylor Heart and Vascular Institute, Department of Pathology, Baylor University Medical Center, Dallas, TX 75246, USA. wc.roberts@baylorhealth.edu
authors.forename: William Clifford
authors.initials: WC
authors.lastname: Roberts
authors.forename: Jong Mi
authors.initials: JM
authors.lastname: Ko
authors.forename: Cody
authors.initials: C
authors.lastname: Hamilton
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001021:Aortic Valve / Q000002:abnormalities / Q000473:pathology* / Q000601:surgery; D001022:Aortic Valve Insufficiency; D001024:Aortic Valve Stenosis / Q000473:pathology / Q000601:surgery*; D001794:Blood Pressure; D001026:Coronary Artery Bypass; D005260:Female; D019918:Heart Valve Prosthesis Implantation / Q000639:trends*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009929:Organ Size