Transapical Mitral Valved Stent Implantation

Background Transcatheter aortic and pulmonary valve replacement is currently being tested in human trials. Efforts to create a valved stent to replace the atrioventricular valves have shown limited success. This is due to their their complex anatomy and function. Methods A self-expanding valved stent was created for transapical replacement of the atrioventricular valve. Ten pigs underwent transapical off-pump mitral valved stent implantation. Data were gathered to assess the animalsʹ hemodynamic stability for 60 minutes after implantation. The valved stent function was assessed by transesophageal echocardiography (TEE) and contrast left ventriculogram. Results All animals exhibited normal hemodynamics immediately after mitral valved stent implantation and maintained stability for the entire period of monitoring. Accurate positioning of the valved stent was established in all animals. Mild paravalvular regurgitation was found in three out of ten animals by TEE and in two animals during left ventriculogram. No left ventricular outflow tract obstruction was encountered. Conclusions Transapical off-pump mitral valved stent implantation is feasible in an acute experimental setting. Long-term function of the new valved stent remains to be established.