Transcervical Robot Assisted Aortic Valve Replacement: Proof of Concept and Minimally Invasive Surgical Technique

Background: A minimally invasive surgical technique for aortic valve replacement using a custom surgical retractor specifically designed for transcervical approach to cardiothoracic surgery has previously been described. We hypothesized that the adjunct and integration of robotic technology may improve surgical dexterity and render the transcervical approach advantageous over lateral approaches for robotic aortic valve replacement (AVR). We therefore sought to evaluate its feasibility. This is a preclinical cadaveric feasibility study; no human outcomes are reported. Clinical validation will be addressed in future trials. Methods: A dry lab was firstly set up in the robotic operating room (OR) to explore the concept, with chest phantom incorporating synthetic aortic root mounted atop the surgical table. The minimally invasive surgery was then repeated on five fresh frozen cadavers using an identical setup. The specially designed transcervical retractor system was mounted on the table for exposure. A da Vinci Xi robot was docked from the side and arms allocated for instrumentation or camerascope. Key steps of AVR were performed by console and bedside surgeons working in harmony. Objective procedural metrics were prospectively recorded for each cadaver, including pericardial opening time, aortotomy creation, leaflet excision, prosthesis delivery, inspection and deployment, and aortotomy closure. All times were measured from video timestamps by two independent observers. Results: Quantitative findings are summarised. A transient loss of visualisation occurred once when adipose tissue obscured the 30° scope; switching to a 0° lens resolved the issue. No difficulty was encountered passing the prosthesis through the uniportal access; however, in two cadavers mild resistance required momentary elevation of the sternum via the retractor ratchet. The cadaver provided a realistic representation of transcervical anatomy, surgical approach for detailing instrumentation and OR setup, similar to live surgery. Key steps of the aortic valve replacement procedure were successfully executed by console surgeon and bedside assistant working in harmony and integrating the use of the robot with the specially designed transcervical retractor system. Conclusions: Advanced Videoscopic Aortic surgery, Transcervical Approach, Robot assisted (AVATAR) AVR looks feasible. Key steps were easily performed with the robot when used in cooperation with the robot enabling retraction system.