Invited commentary

Abstract

The median sternotomy has remained the primary incision for all cardiac operations. Therefore, surgeons rarely have been concerned with chest wall topography as related to specific cardiac regions. Nevertheless, spatial projections of intercostal entry points onto cardiac surgical sites vary widely. The thorax is a complex semirigid, paraboloid cage that encloses a dynamic organ (ie, the heart). Until now alignment of robotic instrument entry points with cardiac operative sites has been difficult, even on an arrested heart and with the use of visual cues through a small incision. Comparatively, the elastic abdominal wall can be mobilized to align instrument entry points with multiple operative targets. In robotic cardiac surgery exact placement, the operative “triplet” (3-dimensional [3-D] camera and two instrument arms) amplify these complexities. Heretofore, the frustration of trocar placement and instrument vector alignment with the operative plane has been an impediment to widespread adoption of robotic cardiac surgery. Moreover, in a closed chest, work-space limitations can distort visual cues, eventuating in grafting the wrong target vessel. To help resolve these problems, Falk and Coste-Manière in collaboration with colleagues at the Leipzig Heart Center, designed and applied a pioneering cardio-navigation system both experimentally and clinically. This “surgical global positioning satellite” prototype was designed to plan, simulate, and augment closed-chest coronary operations using robotic devices. Robotic instrument positions were integrated electronically with visual overlay models of target vessels, derived from computed tomographic acquired anatomic registrations and coronary angiograms. These methods, validated in animal models and applied for the first time clinically, could become the spring-board needed to enable robotic cardiac surgery to evolve. The resolution of computed tomographic scanners is improving logarithmically, and newer devices should be easier to integrate with next generation robotic technology. With this evolution the iterative steps and time required for data acquisition, processing, modeling, instrument positioning, and visual augmentation will be reduced. These methods could provide the pathway to develop training algorithms and visual modeling of every cardiac operation. By combining future cardio-navigation systems with smaller 3-D cameras, improved image registration, smaller instruments, intracardiac 3-D echocardiography, and perhaps nano-robotic devices, a new frontier in cardiac surgery may emerge. Falk and Cost-Maniere are to be congratulated for their collaboration in developing this project and for carrying it to a successful clinical application. However, their work is just beginning.