title: Serial Doppler echocardiographic evaluation of small-sized sorin bicarbon prostheses.
abstract: OBJECTIVE
  The Sorin Bicarbon prosthesis (Sorin Biomedica, Saluggia, Italy) is a bileaflet valve with curved-profile leaflets, a rolling hinge mechanism, and a pyrolytic carbon-coated titanium alloy housing and sewing ring. Although the Sorin Bicarbon prosthesis has been implanted in greater than 80,000 patients, and reference values on the hemodynamic performance of valve prostheses are needed to avoid patient-prosthesis mismatch, few Doppler echocardiographic data are available on the prosthesis in the aortic position. The aim of this study is to provide a detailed echocardiographic evaluation of the hemodynamic performance and regression of left ventricular hypertrophy after aortic valve replacement with the Sorin Bicarbon prosthesis.
  
  
  METHODS
  The study included 182 patients who received a 21-mm (n = 61) or 23-mm (n = 121) Sorin Bicarbon prosthesis for pure or prevalent aortic stenosis who underwent serial echocardiograms at 3, 6, and 12 months after aortic valve replacement.
  
  
  RESULTS
  Mean and peak gradients significantly decreased (P <.001) during follow-up to values of 12 +/- 3 and 22 +/- 6 mm Hg for the 21-mm prosthesis and values of 11 +/- 4 and 19 +/- 6 mm Hg for the 23-mm prosthesis at 1 year. Left ventricular mass index showed a 17% decrease to 120 +/- 27 g/m(2) in recipients of the 21-mm prosthesis (P <.001) and a 21% decrease to 123 +/- 29 g/m(2) in recipients of the 23-mm prosthesis (P <.001). A larger prosthesis size was the only predictor of a higher left ventricular mass index regression. Among recipients of the 21-mm prosthesis, body surface area of greater than 1.85 m(2) was associated with a lower regression of left ventricular mass index. The effective orifice area index was 1.00 +/- 0.11 and 1.08 +/- 0.14 cm(2)/m(2) in recipients of the 21-mm and 23-mm prostheses, respectively.
  
  
  CONCLUSIONS
  Size 21 mm and 23 mm Sorin Bicarbon prostheses show low transprosthetic gradients, with significant reduction of left ventricular mass index during the first postoperative year. The reported effective orifice areas might be useful for aortic valve replacement in patients with a small aortic annulus to avoid patient-prosthesis mismatch.
authors.affiliation: Cardiothoracic Department, University of Pisa Medical School, 56124 Pisa, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: De Carlo
authors.forename: Aldo D
authors.initials: AD
authors.lastname: Milano
authors.forename: Carmela
authors.initials: C
authors.lastname: Nardi
authors.forename: Gianclaudio
authors.initials: G
authors.lastname: Mecozzi
authors.forename: Uberto
authors.initials: U
authors.lastname: Bortolotti
mesh_terms: D000368:Aged; D001024:Aortic Valve Stenosis / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery*; D001794:Blood Pressure / Q000502:physiology; D001830:Body Surface Area; D018618:Echocardiography, Doppler, Color; D005260:Female; D005500:Follow-Up Studies; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000295:instrumentation; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery; D007558:Italy; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000000981:diagnostic imaging / Q000209:etiology / Q000503:physiopathology; D011474:Prosthesis Design; D012044:Regression Analysis; D013318:Stroke Volume / Q000502:physiology; D013599:Systole / Q000502:physiology; D013997:Time Factors; D016896:Treatment Outcome