title: Clinical course and hemodynamic observations after supraannular mitral valve replacement in infants and children.
abstract: OBJECTIVE
  We report the clinical course and unique hemodynamic findings after placement of a supraannular mitral valve prosthesis.
  
  
  BACKGROUND
  Children with symptomatic mitral valve disease whose annulus is too small for the smallest prosthesis are difficult to manage. One option is valve replacement with a prosthesis positioned entirely within the left atrium (LA).
  
  
  METHODS
  We reviewed 17 patients (median age 10 months) with symptomatic mitral valve disease who underwent placement of a supraannular valve prosthesis between 1980 and 1994.
  
  
  RESULTS
  The actuarial survival rates were 88% at 1 month and 71%, 62% and 53% at 1, 2 and 10 years, respectively. Preoperative hemodynamic data (mean +/- SD)) compared with those after placement of the supraannular mitral prosthesis were as follows: "a" wave to left ventricular end-diastolic pressure gradient 17 +/- 5 versus 4 +/- 4 mm Hg (p = 0.003), mean LA pressure 25 +/- 6 versus 20 +/- 6 mm Hg (p = 0.07), "a" wave 30 +/- 6 versus 19 +/- 5 mm Hg (p = 0.006), "v" wave 28 +/- 5 versus 30 +/- 9 mm Hg (p = 0.31), mean pulmonary artery pressure 54 +/- 19 versus 42 +/- 15 mm Hg (p = 0.07) and left ventricular end-diastolic pressure 14 +/- 5 versus 16 +/- 4 mm Hg (p = 0.12).
  
  
  CONCLUSIONS
  Supraannular mitral valve replacement provides relief of mitral stenosis or mitral regurgitation. However, LA to left ventricular early diastolic gradients with large atrial "v" waves contribute to elevated mean LA pressures in the absence of prosthetic valve obstruction or regurgitation. As a result of this unexpected finding, associated left heart obstructive lesions and pulmonary and left ventricular end-diastolic hypertension, the outlook remains poor.
authors.affiliation: Department of Cardiology, Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA. ian.adatia@mailhub.sickkids.on.ca
authors.forename: I
authors.initials: I
authors.lastname: Adatia
authors.forename: P M
authors.initials: PM
authors.lastname: Moore
authors.forename: R A
authors.initials: RA
authors.lastname: Jonas
authors.forename: S D
authors.initials: SD
authors.lastname: Colan
authors.forename: J E
authors.initials: JE
authors.lastname: Lock
authors.forename: J F
authors.initials: JF
authors.lastname: Keane
mesh_terms: D002675:Child, Preschool; D017023:Coronary Angiography; D004452:Echocardiography; D005260:Female; D006349:Heart Valve Diseases / Q000000981:diagnostic imaging / Q000401:mortality / Q000503:physiopathology / Q000601:surgery*; D006350:Heart Valve Prosthesis; D006439:Hemodynamics; D006801:Humans; D007223:Infant; D008297:Male; D008943:Mitral Valve; D012189:Retrospective Studies; D015996:Survival Rate; D016896:Treatment Outcome