Self-Expandable Stent Valve For Transatrial Off-Pump Mitral Valve-In-Ring Implantation After Mitral Valvuloplasty In Vivo Swine

Objective:To study the feasibility of a self-expandable stent valve for transatrial mitral valve-in-ring implantation after mitral valvuloplasty in vivo swine.Method:An independent hand-made self-expandable stent valve was prepared with a improved delivery system. The experimental swine underwent a mitral vavuloplasty under CPB. Then the swine’s chest was opened through the left intercostal incision. The self-expandable stent valve was thereafter off-pump implanted through the transatrial pathway under fluoroscopy guidance.Result:8of the9swine experienced a satisfied procedure, the other one failed because the stent was expanded intra-ventricle. The echocardiography showed the implanted valve worked well, with mild regurgitation in7and moderate in1, but no para-valvular leak was detected. The pressure gradient across the self-expandable stent or across left ventricular outflow tract (LVOT) was no statistical difference. The postmortem examination showed the good positioning of stents within the annuloplasty rings in8animals, without LVOT obstruction.Conclusion:The hand-made self-expandable stent valve and the improved delivery system work well. And the procedure of self-expandable stent valve for Transatrial off-pump mitral valve-in-ring implantation after mitral valvuloplasty in vivo swine is safe and feasilble.