Minimally Invasive Cardiac Surgery: Transapical Aortic Valve Replacement

Cardiothoracic Surgery Research Program, National Heart, Lung, and Blood Institute, National Institutes of Health, 9000 Rockville Pike, Bldg 10, B1D47, Bethesda, MD 20892, USA.
Minimally invasive surgery 10/2012; 2012:145381. DOI: 10.1155/2012/145381
Source: PubMed

ABSTRACT Minimally invasive cardiac surgery is less traumatic and therefore leads to quicker recovery. With the assistance of engineering technologies on devices, imaging, and robotics, in conjunction with surgical technique, minimally invasive cardiac surgery will improve clinical outcomes and expand the cohort of patients that can be treated. We used transapical aortic valve implantation as an example to demonstrate that minimally invasive cardiac surgery can be implemented with the integration of surgical techniques and engineering technologies. Feasibility studies and long-term evaluation results prove that transapical aortic valve implantation under MRI guidance is feasible and practical. We are investigating an MRI compatible robotic surgical system to further assist the surgeon to precisely deliver aortic valve prostheses via a transapical approach. Ex vivo experimentation results indicate that a robotic system can also be employed in in vivo models.

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    ABSTRACT: This paper reports our work on developing a robotic surgical system for transapical beating heart aortic valve replacement (AVR) under interactive real-time magnetic resonance imaging (rtMRI) guidance. Our system integrates a real-time MRI system, a compound MRI robot, as well as an interface for the surgeon to plan the procedure and manipulate the robot. The compound robot consists of a positioning module and a valve delivery module. A 5-DOF Innomotion positioning arm provides and maintains direct access to the native aortic valve. A newly developed 3-DOF robotic valve delivery module allows the surgeon to remotely control bioprosthetic valve delivery with MRI guidance. Preliminary evaluation of the parameters of the robotic system demonstrates it can provide sufficient capability to successfully assist the surgeon.
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