title: [Doppler echocardiographic assessment of CarboMedics prosthesis in patients with mitral valve replacement].
abstract: OBJECTIVE
  To evaluate the CarboMedics (CM) prosthesis function two years after mitral valve replacement, and to compare the effective orifice area (EOA) calculated by pressure half-time (PHT) method and continuity method (CON).
  
  
  METHODS
  Forty nine patients who underwent isolated mitral valve replacement with a CM prosthesis were recruited in this study, which included 13 cases of 25 mm CM prosthesis and 36 cases of 27 mm CM prosthesis. Two years after the mitral valve replacement, transthoracic echocardiography (TTE) was performed, measuring left ventricular ejection fraction (LVEF), stroke volume mean gradient (SV), PHT, peak early mitral diastolic velocity (E velocity), mean gradient (MG), time-velocity integral of left ventricular outflow tract/time-velocity integral of mitral valve prosthesis (TVI(MVP)/TVI(LVOT)). The function of the prosthetic valve was considered normal when PHT < 130 ms, E velocity < 2.0 m/s and TVI(MVP)/TVI(LVOT) < 2.2.
  
  
  RESULTS
  More than half (53.1%) of the patients had normal function of the prosthetic valve. No significant differences were found in PHT, MG, TVI(MVP)/TVI(LVOT), EOA or IEOA between the patients with 25 mm valve and the patients with 27 mm valve (P > 0.05). But the patients with 25 mm valve had higher E velocity than the patients with 27 mm valve (P < 0.05). The PHT method produced greater EOA than by the CON method (P < 0.05).
  
  
  CONCLUSIONS
  The function of CM prosthesis is acceptable two years after the mitral valve replacement, with most patients having PHT < 130 ms, E velocity < 2.0 m/s and TVI(MVP)/TVI(LVOT) < 2.2. PHT method produces greater EOA than CON method.
authors.affiliation: Division of Thoracic and Cardiovascular Surgery, West China Hospital, Sichuan University, Chengdu 610041, China.
authors.forename: Dong-Ming
authors.initials: DM
authors.lastname: Wei
authors.forename: Hong
authors.initials: H
authors.lastname: Tang
authors.forename: Wen-Zia
authors.initials: WZ
authors.lastname: Zhou
authors.forename: Bo
authors.initials: B
authors.lastname: Xiang
authors.forename: Hao
authors.initials: H
authors.lastname: Rong
authors.forename: Hong-Sheng
authors.initials: HS
authors.lastname: Yuan
authors.forename: Xi-Jun
authors.initials: XJ
authors.lastname: Xiao
mesh_terms: D000328:Adult; D000368:Aged; D015150:Echocardiography, Doppler; D005260:Female; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000000981:diagnostic imaging* / Q000503:physiopathology* / Q000601:surgery; D011184:Postoperative Period; D012189:Retrospective Studies; D055815:Young Adult