title: [Mitral valve replacement with porcine bioprosthesis in children. Evaluation of 29 patients during 12 years].
abstract: OBJECTIVE
  To analyze the clinical result of the mitral valve substitution for the porcine bioprostheses, the incidence of dysfunction caused by calcification and its importance related to the durability of bioprostheses and also the patients' survival.
  
  
  METHODS
  Twenty-nine children of about seven to sixteen years old were operated on from November 1977 to August 1982 and all of them received porcine bioprostheses of low profile.
  
  
  RESULTS
  There were three (10.34%) hospital deaths and nine other late mortalities. The follow-up period varied from 4 to 128 months with average of 58.17 months and with the loss of nine patients. An actuarial survival rate of 46.08% has been observed at 11 years after surgery. Calcification of 21 bioprostheses occurred in 14 out of 17 follow-up patients; 47.6% of them happened until the third year of pos-operative and 85.7% until the fifth year. Eleven patients were reoperated on with 9.09% of hospital mortality. There were no cases of thromboembolism.
  
  
  CONCLUSIONS
  Porcine bioprostheses works well with an evident clinical improvement of patients, with no thromboembolic accidents. However, its durability has been affected by the high incidence of calcification, which is responsible for an increase in late morbidity and mortality. Mitral valve disease treatment in children must be conservative, in an attempt to solve the problem with the different available plastic technics and leave the valve substitution to be a last option. In that case, the preference is given to the homologous bioprostheses.
authors.affiliation: Hospital da Santa Casa de Misericórdia de São Paulo e Hospital Samaritano.
authors.forename: S M
authors.initials: SM
authors.lastname: Gandra
authors.forename: L A
authors.initials: LA
authors.lastname: Rivetti
authors.forename: A M
authors.initials: AM
authors.lastname: Pinto
authors.forename: I
authors.initials: I
authors.lastname: Marinelli
authors.forename: V P
authors.initials: VP
authors.lastname: Campagnucci
authors.forename: R A
authors.initials: RA
authors.lastname: Franken
mesh_terms: D000206:Actuarial Analysis; D000293:Adolescent; D001705:Bioprosthesis; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006349:Heart Valve Diseases / Q000601:surgery; D006350:Heart Valve Prosthesis / Q000401:mortality*; D006801:Humans; D008297:Male; D008943:Mitral Valve / Q000601:surgery
vernacular_title: Substituição valvar mitral por bioprótese porcina em crianças. Avaliação de 29 pacientes durante 12 anos.