title: Preoperative evaluation of patient anatomy to increase success of robotics-assisted bypass surgery.
abstract: OBJECTIVE
  Robotics-assisted endoscopic atraumatic coronary artery bypass has been shown to be effective in reducing surgical morbidity and length of hospital stay. Unfortunately, the criteria for selecting eligible patients for this procedure are still primitive. This has motivated the use of preoperative computed tomography scans to establish patient eligibility. The objective of this study is to establish which image measurements can be correlated to procedure success.
  
  
  METHODS
  A retrospective study was performed in 144 patients who underwent robotics-assisted coronary bypass surgery. After an initial set of 55 patients, preoperative computed tomography scans of the other patients were used to obtain patient specific measurements: the lateral distance between the midline of the sternum to the left anterior descending coronary artery and its depth from the skin surface, anteroposterior diameter of the thoracic cavity, and the transverse diameter of the thoracic cavity. The procedures were rated as successful if completed in a minimally invasive manner. Different combinations of the variables were evaluated and correlated with success.
  
  
  RESULTS
  A strong correlation was found between success rate and the ratio of the lateral distance to the transverse diameter in the female patients only (0.532, P = 0.006). A ratio of less than 0.20 significantly increased the occurrence of conversion during this procedure in female cases.
  
  
  CONCLUSIONS
  The lateral distance of the left anterior descending coronary artery from the midline divided by the transverse thoracic width of a female patient shows a significant correlation with procedure success. No significant correlations were found for male patients.
authors.affiliation: Canadian Surgical Technologies & Advanced Robotics-CSTAR, Lawson Health Research Institute, London, ON, Canada.
authors.forename: Ana Luisa
authors.initials: AL
authors.lastname: Trejos
authors.forename: Ian
authors.initials: I
authors.lastname: Ross
authors.forename: Carlie
authors.initials: C
authors.lastname: Scalesse
authors.forename: Rajni V
authors.initials: RV
authors.lastname: Patel
authors.forename: Michael D
authors.initials: MD
authors.lastname: Naish
authors.forename: Bob
authors.initials: B
authors.lastname: Kiaii