Background: Ideal heart valve prosthesis is yet to be discovered but recent stentless bioprosthetic valves carry similar properties with homograft valves which resambles to native valves hemodynamically. Our study was carried out to investigate the O’Brien bioprosthetic valves on aortic position, to early and mid term left ventricule mass and mass index results.

Method: During the period between October 1999 and July 2000, 15 patients had aortic valve replacement with O’Brien stentless composite porcine bioprosthesis at Türkiye Yüksek İhtisas Hospital Cardiovascular Surgery Department. 10 (67 %) patients were male and 5 ( 33 %) were female and mean age was 64.9 ± 13.7 years. Two patients were lost in early postoperative period, but both were not related to valve and maximum and mean gradients and velocities of the prosthesis were all lose to phsysiologic limits. Starting with early postoperative period along with clinical improvements, left ventricular end diastolic diameters, wallthicknesses, left ventricular mass (LVM) and mass indexes (LVMI) started to decline, but reached to statistical significance after 6th postoperative month.

Results: All the end of one year mean LVM drapped from 329±75.4gr to 246.9±80.5gr (p=0.02) and mean LVMI drapped from 192.7±39.5 gr/m2 to 142.3±39.3 gr/m2 (p=0.009). Patients were followed for a mean period of 13.0±3.8 months and no valve dysfunction, prosthetic valve endocarditis, paravalvular leakage and hemolysis due to prosthesis were observed.

Conclusion: Use of stentless bioprosthetic valves outlines the necessity of oral anticoagulant usage and consequently bleeding and thromboembolic incidences are rarely seen. Stentless bioprosthetic valves provides along with clinical recovery, an almost perfect regression of left ventricular hypertrophy. Their late term results are yet to be reported but with perfect hemodynamic performances, stentless bioprosthetic valves provide regression of ventricular hypertrophy.

Keywords : Stenless, bioprothesis, aortic valve replacement, left ventricule