Robotic-assisted instruments enhance minimally invasive mitral valve surgery

Background. The potential for totally endoscopic mitral valve surgery has been advanced by the development of minimally invasive techniques. Recently surgical robots have offered instrument access through small ports, obviating the need for a significant thoracotomy. This study tested the hypothesis that a microsurgical robot with 5 degrees of freedom is capable of performing an endoscopic mitral valve replacement (MVR). Methods. Dogs (n = 6) were placed on peripheral cardiopulmonary bypass; aortic occlusion was achieved with endoaortic clamping and transesophageal echocardiographic control. A small left seventh interspace “service entrance” incision was used to insert sutures, retractor blade, and valve prosthesis. Robotically controlled instruments included a thoracoscope and 5-mm needle holders. MVR was performed using an interrupted suture technique. Results. Excellent visualization was achieved with the thoracoscope. Instrument setup required 25.8 minutes (range 12 to 37); valve replacement required 69.3 ± 5.39 minutes (range 48 to 78). MVR was accomplished with normal prosthetic valve function and without misplaced sutures or inadvertent injuries. Conclusions. This study demonstrates the feasibility of adjunctive use of robotic instrumentation for minimally invasive MVR. Clinical trials are indicated.