title: Segmental wall motion abnormalities during telerobotic totally endoscopic coronary artery bypass grafting.
abstract: In addition to single-lung ventilation (SLV), intrathoracic CO2 insufflation is mandatory for adequate exposure during totally endoscopic coronary artery bypass grafting. With transesophageal echocardiography, we investigated biventricular myocardial wall motion in 25 patients with isolated disease of the left anterior descending coronary artery who underwent totally endoscopic coronary artery bypass grafting with the "Da Vinci" robotic surgical system. At distinct time points during the operation, a cine loop of both ventricles was registered from a transgastric mid-short-axis view. Myocardial wall motion analysis was performed according to an established segmentation model of the left ventricle and to an established five-point scale for wall motion (1, normal; 5, dyskinesia). Significant alterations from preoperative baseline wall motion were visible in the septal, inferior, and anterior segments of the left ventricle at some time during the prebypass period, combined with a markedly decreased PaO2 under SLV and increased intrathoracic pressure. The same findings applied to the right ventricle; however, wall motion abnormalities were more pronounced here. After myocardial revascularization, weaning from cardiopulmonary bypass, CO2 deflation, and return to double-lung ventilation, myocardial wall motion recovered to baseline values. Clinically significant hemodynamic instability did not occur. The data suggest that robot-assisted coronary artery bypass grafting leads to significant prebypass alterations of biventricular segmental wall motion. On the basis of our data, it cannot be definitively stated whether the observed results were due to reduced oxygenation during SLV and thus "real" myocardial ischemia, intrathoracic CO2 insufflation with positive pressure leading to mechanical compromise of the heart, absolute or relative hypovolemia, or a combination of these factors. However, in this cohort, which consisted of patients with single-vessel disease and good ventricular function, these changes were of limited clinical relevance.
  
  
  CONCLUSIONS
  Segmental myocardial wall motion was evaluated with transesophageal echocardiography during robot-assisted totally endoscopic coronary artery bypass grafting. Significant biventricular segmental wall motion abnormalities occurred before cardiopulmonary bypass under single-lung ventilation and carbon dioxide insufflation. The changes in myocardial wall motion were of limited clinical relevance.
authors.affiliation: Department of Anesthesiology, J. W. Goethe-University Hospital Center, Frankfurt, Germany.
authors.forename: Stephan
authors.initials: S
authors.lastname: Mierdl
authors.forename: Christian
authors.initials: C
authors.lastname: Byhahn
authors.forename: Selami
authors.initials: S
authors.lastname: Dogan
authors.forename: Tayfun
authors.initials: T
authors.lastname: Aybek
authors.forename: Gerhard
authors.initials: G
authors.lastname: Wimmer-Greinecker
authors.forename: Paul
authors.initials: P
authors.lastname: Kessler
authors.forename: Dirk
authors.initials: D
authors.lastname: Meininger
authors.forename: Klaus
authors.initials: K
authors.lastname: Westphal
mesh_terms: D002245:Carbon Dioxide / Q000008:administration & dosage; D001026:Coronary Artery Bypass; D017548:Echocardiography, Transesophageal; D004724:Endoscopy; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D009200:Myocardial Contraction; D011031:Pneumothorax, Artificial; D012121:Respiration, Artificial; D012371:Robotics; D013318:Stroke Volume; D016276:Ventricular Function
chemical_list: D002245:Carbon Dioxide