title: Mechanical aortic and mitral valve replacement in infants and children.
abstract: BACKGROUND
  The aim of this study was to evaluate early and late outcomes after mechanical systemic heart valve replacement in pediatric patients.
  
  
  METHODS
  Between October 1981 and December 2003, 32 children (mean age 7.2 +/- 5.4 years; 4 months - 15.9 years) underwent mechanical mitral (MVR, n = 17), aortic (AVR, n = 13) or double valve replacement (DVR, n = 2) with St. Jude Medical valves. Twenty-two patients (69 %) had undergone previous cardiac surgery. Anticoagulation self-management was used since 1995.
  
  
  RESULTS
  The operative mortality was 3.1 %. Perioperative complications were complete heart block (n = 5), ventricular fibrillation (n = 1) and myocardial infarction (n = 1) and were exclusively related to patients with MVR. Mean calculated valve size ratio (geometric prosthesis orifice area/normal valve size area) was 1.72 (1.07 - 2.85) for AVR and 1.4 (0.88 - 3.12) for MVR. Mean follow-up was 9.1 +/- 6.6 years (range 0.4 - 23.2 years, cumulative 283 patient-years). There were two late deaths in patients with MVR. Actuarial survival after 10 years was 93.8 %. Late complications were endocarditis (n = 2), minor hemorrhagic event (n = 1), and stroke (n = 1). Anticoagulation self-management is well accepted by all patients/parents. Overall 10-year freedom from any anticoagulation-related adverse event with phenprocoumon was 89.1 % (1.2 %/patient year). Nine patients required reoperations: redo-MVR (outgrowth of prostheses (n = 3), pannus overgrowth (n = 2), closure of paravalvular leak after AVR (n = 2), partial aortic valve thrombosis (n = 1) and redo-DVR (n = 1 for endocarditis). Freedom from reoperation after 10 years was 80.9 %.
  
  
  CONCLUSIONS
  Mechanical valve prostheses are a valuable option for left-sided heart valve replacement in pediatric patients. Perioperative morbidity was exclusively related to patients with MVR. Oversizing was often possible to avoid early reoperation for outgrowth. The operative mortality and long-term morbidity are acceptable. Anticoagulation self-management is safe and well accepted.
authors.affiliation: Department of Thoracic and Cardiovascular Surgery, Pediatric Cardiac Surgery, RWTH Aachen University Hospital, Aachen, Germany. jsachweh@ukaachen.de
authors.forename: J S
authors.initials: JS
authors.lastname: Sachweh
authors.forename: A R
authors.initials: AR
authors.lastname: Tiete
authors.forename: E G
authors.initials: EG
authors.lastname: Mühler
authors.forename: J
authors.initials: J
authors.lastname: Groetzner
authors.forename: H
authors.initials: H
authors.lastname: Gulbins
authors.forename: B J
authors.initials: BJ
authors.lastname: Messmer
authors.forename: S H
authors.initials: SH
authors.lastname: Daebritz
mesh_terms: D000206:Actuarial Analysis; D000293:Adolescent; D000925:Anticoagulants / Q000009:adverse effects; D001021:Aortic Valve; D002648:Child; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D006349:Heart Valve Diseases / Q000601:surgery*; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation / Q000401:mortality; D006801:Humans; D007223:Infant; D008297:Male; D008943:Mitral Valve; D019106:Postoperative Hemorrhage / Q000209:etiology; D011475:Prosthesis Failure; D012086:Reoperation; D013923:Thromboembolism / Q000209:etiology; D016896:Treatment Outcome
chemical_list: D000925:Anticoagulants