title: The increasing use of mechanical pulmonary valve replacement over a 40-year period.
abstract: BACKGROUND
  Because reoperation is often necessary for bioprostheses, mechanical pulmonary valve replacement (mPVR) may be appropriate for many patients. Mechanical prostheses are durable, but there has been concern concerning valve thrombosis and bleeding complications from warfarin.
  
  
  METHODS
  Between October 1965 and August 2008, 54 patients (33 male, median age 30 years, range 5 to 66) underwent mechanical PVR at our institution (40 patients since 2004). Forty-nine of these 54 patients underwent a total of 110 prior operations (median 2, maximum 5), including 89 prior operations on the right ventricular outflow tract (median 1, maximum 4). Diagnoses included congenital (n = 47) and carcinoid (n = 7) heart disease. Bleeding complications were compared with a 1:2 matched patient cohort (age, gender, and diagnosis) receiving bioprosthetic PVR.
  
  
  RESULTS
  The most common concomitant procedures were tricuspid valve replacement in 15 patients, aortic root replacement in 14, and aortic valve replacement in 13. At last follow-up in 45 of 51 early survivors (median 2.2 years, maximum 20 years), there was no perivalvular leak, vegetations, pannus formation, or valve thrombosis. Further, no patient required reoperation on mPVR. Major late bleeding complications occurred in 3 of 54 patients in the mPVR group and 4 of 108 in the tissue PVR group.
  
  
  CONCLUSIONS
  Thromboembolic complications are rare with therapeutic international normalized ratios and mechanical PVR provides excellent durability and freedom from reoperation. Tissue PVR does not eliminate bleeding complications. Mechanical PVR should be considered in select patients with multiple prior operations, or when there is another need for warfarin anticoagulation.
authors.affiliation: Division of Cardiovascular Surgery, Mayo Clinic and Foundation, Rochester, Minnesota 55905, USA.
authors.forename: John M
authors.initials: JM
authors.lastname: Stulak
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Dearani
authors.forename: Harold M
authors.initials: HM
authors.lastname: Burkhart
authors.forename: Heidi M
authors.initials: HM
authors.lastname: Connolly
authors.forename: Carole A
authors.initials: CA
authors.lastname: Warnes
authors.forename: Rakesh M
authors.initials: RM
authors.lastname: Suri
authors.forename: Hartzell V
authors.initials: HV
authors.lastname: Schaff
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001705:Bioprosthesis; D002648:Child; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D006349:Heart Valve Diseases / Q000601:surgery*; D006350:Heart Valve Prosthesis / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011474:Prosthesis Design; D011475:Prosthesis Failure; D011664:Pulmonary Valve / Q000601:surgery*; D012086:Reoperation / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D013923:Thromboembolism / Q000209:etiology / Q000517:prevention & control*; D013997:Time Factors; D055815:Young Adult