and three interactive table-mounted instrument manipulators. Details of this system have been previously described.1 Starting September 18, 1999, 18 patients with single-vessel coronary disease involving the left anterior descending coronary artery underwent beating-heart minimally invasive coronary artery bypass grafting with telerobotic assistance after approval by the university’s institutional ethics committee. Totally robotic, closed-chest procedures were completed in 6 male patients and are the subject of this report. After establishment of general anesthesia with a doublelumen endotracheal tube, each patient was placed in a 45° right lateral decubitus position. The left arm was abducted to permit the insertion of three 5-mm access ports, while avoiding external robotic arm collisions. The left internal thoracic artery (LITA) was identified and dissected as a pedicle from the first to sixth ribs with voice-activated robotic and video assistance using the Harmonic Scalpel (Ethicon EndoSurgery, Inc, Somerville, NJ). During the procedure, warm carbon dioxide gas was insufflated into the pleural cavity up to a pressure of 5 to 10 mm Hg. The left anterior descending coronary artery (LAD) was stabilized with a prototype articulating endoscopic stabilizer (Fig 1). A specially designed sternal elevator was used in 3 of the patients to increase anteroposterior intrathoracic working space. A 5-mm 0° endoscope and assistant instruments were passed through working ports. The patients were then systemically heparinized and the LAD prepared for anastomosis. The LITA Significant advances have been made in computer-assisted robotic coronary surgery in the past 2 years. Although limited success has been achieved with totally endoscopic, robotassisted bypass on the arrested heart, the ultimate objective is to perform a beating-heart procedure. To date, technical limitations have prevented this goal from being accomplished. We describe our initial clinical experience using robotic instrumentation and voice-controlled camera guidance (Zeus; Computer Motion Inc, Goleta, Calif) in performing closedchest, beating-heart coronary artery bypasses. Patients and methods. The Zeus endoscopic instrument control system is a supervised online robotic system consisting of three components: a surgeon’s console, a computer controller, CLOSED-CHEST CORONARY ARTERY BYPASS GRAFTING ON THE BEATING HEART WITH THE USE OF A COMPUTER-ENHANCED SURGICAL ROBOTIC SYSTEM