ABSTRACT
BACKGROUND: With traditional instruments, endoscopic coronary artery bypass grafting (ECABG) has not been possible. This study was designed to determine the feasibility of using a robotically-assisted microsurgical system to perform ECABG in a chronic animal model. METHODS: Nine calves were placed on cardiopulmonary bypass after harvesting the left internal mammary artery (LIMA). Subxiphoid endoscopic ports (2 instrument, 1 camera) were placed, and a robotic system was used to perform ECABG between the LIMA and left anterior descending coronary artery. LIMA graft flow (LIMAQ) was measured. Animals were sacrificed at 1 month, and hearts underwent angiographic and histologic analyses. RESULTS: Acute graft patency was 89% (8/9). Two animals died suddenly within the first 48 hours. There was no significant difference in mean acute and chronic (n = 6) LIMAQ (40.9+/-4.7 and 38.5+/-5.0 ml/min, respectively). Survivors had an angiographic patency rate of 100% (6/6), confirmed by histology. CONCLUSIONS: This study shows that ECABG is feasible in a chronic animal model with excellent results.
Subject(s)
Coronary Artery Bypass/methods , Endoscopy/methods , Robotics , Anastomosis, Surgical/methods , Animals , Cattle , Coronary Angiography , Coronary Circulation , Echocardiography , Endoscopes , Feasibility Studies , Microsurgery/instrumentation , Microsurgery/methods , Therapy, Computer-Assisted , Vascular PatencyABSTRACT
BACKGROUND: Endoscopic coronary artery bypass grafting (ECABG) has not been possible with traditional techniques. This report details our animal experience determining the feasibility of using a robotically-assisted microsurgical system to perform ECABG. METHODS: Following preliminary work using a cadaveric pig heart model, acute and chronic animal studies were performed. Calves were placed on cardiopulmonary bypass after the left internal mammary artery (LIMA) was harvested. Subxiphoid endoscopic ports (2 instrument, 1 camera) were placed and a robotic system was used to perform ECABG between the LIMA and left anterior descending coronary artery. LIMA graft flow (LIMAQ) was measured, and excised hearts underwent angiographic and histologic analyses. RESULTS: All anastomoses were successfully completed in both the acute and chronic studies (mean time of 33.9 +/- 1.9 and 33.2 +/- 3.4 minutes, respectively). Angiographic patency was 100% in both the acute (8/8) and chronic (6/6) studies, which was confirmed by histology. In the chronic study, there was no difference in LIMAQ between intraoperative and autopsy measurements. CONCLUSIONS: This study shows that ECABG is feasible in an animal model with excellent results. The FDA has recently given approval for clinical trials of this new technology.
Subject(s)
Coronary Artery Bypass/instrumentation , Robotics/instrumentation , Thoracoscopes , Animals , Cattle , Equipment Design , Female , Humans , Male , Myocardial Revascularization/instrumentation , Surgical Instruments , Swine , User-Computer InterfaceABSTRACT
The introduction and widespread acceptance of minimally invasive techniques have revolutionized surgical practice in many disciplines over the last two decades. Endoscopic operations have been shown to reduce patient morbidity and provide a more rapid return to work. Until recently, endoscopic approaches have had little impact on the field of cardiac surgery. Endoscopically-sutured coronary anastomoses have not been possible with conventional endoscopic instruments, due in part to their length and imprecision.
Subject(s)
Coronary Artery Bypass/methods , Endoscopy , Acute Disease , Animals , Cardiopulmonary Bypass , Cattle , Coronary Angiography , Coronary Artery Bypass/instrumentation , Coronary Disease/diagnostic imaging , Coronary Disease/surgery , Disease Models, Animal , Feasibility Studies , Heart Arrest, Induced , Mammary Arteries/diagnostic imaging , Mammary Arteries/transplantation , RoboticsABSTRACT
BACKGROUND: As minimally invasive approaches to cardiac surgery have expanded, a significant number of limitations have become apparent, particularly the lack of adequate precision with standard endoscopic instruments. We hypothesized that the use of robotics would eliminate some of these limitations. METHODS: Twenty-five coronary anastomoses on an isolated porcine heart, using an arterial conduit to the left anterior descending artery, were performed endoscopically with a microsurgical robotic system. Sophisticated robotic engineering was used to control modified endoscopic instruments under direct surgeon control. Computer tremor elimination and motion scaling allowed for precise maneuvering. An arteriotomy was placed in the left anterior descending artery, and an arterial conduit was positioned for anastomosis. The camera and port sites were placed 90 degrees from the long axis of the arteriotomy. A 7-0 Prolene (Ethicon, Somerville, NJ) suture was used to perform the anastomosis in a continuous fashion, begun at the 12 o'clock position and continued counterclockwise. After completion of half of the anastomosis, the conduits were pulled down and the final sutures were placed. The sutures were tied intracorporeally and the procedure was completed. RESULTS: The 25 conduits were successfully completed and showed good probe patency. Average time for completion of the anastomosis was 31.7 +/- 2.0 minutes. Appropriate port placement and orientation, and stabilization of the conduits were critical. The lack of tremor and motion scaling allowed for the precise movements needed to complete an endoscopic microvascular anastomosis. CONCLUSIONS: Coronary artery anastomoses are technically feasible with use of robotic instrumentation. This technology may enable the development of a truly endoscopic approach to bypass surgery.
