D3: Tissue Mechanics

DEVELOPMENT OF A PULSATILE CIRCULATORY SIMULATOR DUPLICATING MOVEMENT OF MITRAL ANNULUS AND PAPILLARY MUSCLES FOR THE ASSESSMENT OF A STENTLESS MITRAL VALVE


Kazuaki Usui1, Jumpei Takada1, Hitoshi Kasegawa2, Mitsuo Umezu1, Kiyotaka Iwasaki1 

 

1Center for Advanced Biomedical Sciences, TWIns, Waseda University, Japan;
2Sakakibara Memorial Hospital, Japan


BACKGROUND: A novel stentless mitral valve (Normo valve) consisted from an anterior and a posterior leaflet using autologous pericardium sutured around a flexible ring (Duran, Medtronic), which possesses physiological annulopapillary continuity. AIMS: The aim of this study is to develop a pulsatile circulatory simulator for the assessment of mitral valves and to evaluate hydrodynamic performances of the Normo valve in comparison with those of the prosthetic valve (Mosaic valve, Medtronic). METHOD: A novel pulsatile circulatory simulator we have developed consists of an elastic left ventricular model which shape was made based on a patient’s CT data (LVEF≧0.6, volume≧110 ml), an overflow tank, a mechanical valve, a compliance tank and a resistive unit and mimics flow and pressure environment in patients. It also reproduces mitral annular movement and relative distance between annulus and papillary muscles. The Normo valve (27 mm) and the mosaic valve (27 mm) were mounted to the ventricular model. The ventricular model was driven at 70 bpm using a pneumatic driver. The hydrodynamic performances were investigated (n=6). RESULT&DISCCUSION: Mean mitral flow was comparable between the Normo and Mosaic valves (3.9 ± 0.1 L/min, 3.9 ± 0.1 L/min; N.S.). Forward flow and regurgitation of the Normo valve was higher than that of the Mosaic valve (Forward flow: 67.8 ± 1.7 ml/beat, 60.9 ± 2.0 ml/beat; P < 0.01, regurgitation: 10.2 ± 0.6 ml/beat, 3.1 ± 0.4 ml/beat; p < 0.01), respectively. The diastolic mean pressure gradient of the Normo valve was lower than that of the Mosaic valve (1.9 ± 0.9 mmHg, 3.1 ± 0.5 mmHg; P < 0.05). CONCLUSION: The pulsatile circulatory simulator for the assessment of the Normo valve with a function of chordae tendineae was successfully developed. It was found that the hydrodynamic performances of the Normo valve were equivalent to those of the Mosaic 

Organised by

Endorsed by

 

        Supported by
 

 

                          
     

       

                             
           
 

        Supporting Media