Süleyman Demirel Üniversitesi, Şevket Demirel Kalp Merkezi, Kalp ve Damar Cerrahisi Kliniği, Isparta

Background: The aim of the current study was to compare hemodynamic performances of the Carbomedics&reg; and On- X&reg; mechanical bileaflet heart valves in the early postoperative period in patients undergoing mitral valve replacement (MVR). Methods: Thirty patients who underwent MVR operations were randomly divided into two groups. Carbomedics&reg; and On-X&reg; mechanical bileaflet mitral valves were implanted in the first group (n=15) and the second group (n=15) of patients, respectively. Hemodynamic measurements were done by echocardiography in the preoperative period and three months after the operation. Results: There were no statistically significant differences between the two groups regarding pre- and postoperative changes that occured in left ventricular end diastolic diameter, left ventricular end sistolic diameter, left atrium diameter, pulmonary artery pressure, ejection fraction and fractional shortening (p>0.05). However, performance index in the Carbomedics&reg; group was higher than that in the On-X&reg; group (0.96±0.15 vs 0.73±0.10) and the difference was statistically significant (p<0.05). Transvalvular peak pressure gradient in the Carbomedics&reg; group was higher than that in the On-X&reg; group (14.20±3.14 vs 11.07±2.89) and the difference was also statistically significant (p<0.05). There was no statistically significant difference for effective orifice area and transvalvular mean pressure gradient between the two groups postoperatively (p>0.05). Conclusions: When echocardiographic data of the On-X&reg; and Carbomedics&reg; mitral mechanical heart valves were compared in the early postoperative period, similar hemodynamic performances were found. We propose that the On-X&reg; heart valve, which has been introduced into clinical use more recently than Carbomedics&reg;, can be used safely in MVR operations.