Open heart bypass surgery is the standard treatment in advanced coronary heart diseases. For an effective
revascularization procedure, optimal placement of the bypass is very important. To accelerate the intraoperative
localization of the anastomosis site and to increase the precision of the procedure, a concept for computer
assistance in open heart bypass surgery has been developed comprising the following steps:
1. Preprocedural planning: A patient-specific coronary map with information on vessel paths and wall plaque
formations is extracted from a multi-slice computed tomography (MSCT). On this basis, the heart surgeon
and the cardiac radiologist define the optimal anastomosis site prior to surgery.
2. Intraoperative navigation: During surgery, data are recorded at the beating heart using a stereo camera
system. After registering the pre- and intraoperative data sets, preprocedural information can be transferred
to the surgical site by overlaying the coronary map and the planned anastomosis site on the live
video stream. With this visual guidance system, the surgeon can navigate to the planned anastomosis site.
In this work, the proposed surgical assistance system has been validated for the left anterior descending coronary
artery (LAD). The accuracy of the registration mechanism has been evaluated in retrospective on patient data
sets and the effects of breathing motion were quantified. The promising results of the retrospective evaluation
led to the in-vivo application of the computer assistance system during several bypass grafting procedures.
Intraoperative navigation has been performed successfully and postoperative evaluation confirms that the bypass
grafts were accurately positioned to the preoperatively planned anastomosis sites.