Myocardial enzyme release in totally endoscopic coronary artery bypass grafting on the arrested heart

Abstract

Objective: Robotic totally endoscopic coronary artery bypass grafting enables coronary artery bypass grafting without sternotomy or thoracotomy. However, longer cardiopulmonary bypass and aortic endo-occlusion times are currently required compared with those of standard coronary artery bypass grafting operations. We investigated whether longer operation times affect the myocardial enzyme release and the postoperative course.

Methods: From 2001 through 2006, 85 patients with a median age of 58 years (range, 31-76 years) underwent totally endoscopic coronary artery bypass grafting on the arrested heart by using the da Vinci telemanipulator and remote access perfusion through the femoral vessels (Estech or Heartport). The operations involved the left internal thoracic artery-left anterior descending coronary artery or diagonal branch (n = 74); right internal thoracic artery-right coronary artery (n = 2); double-vessel left internal thoracic artery-obtuse marginal branch/circumflex artery and right internal thoracic artery-left anterior descending coronary artery (n = 8); and double-vessel left internal thoracic artery-left anterior descending coronary artery and saphenous vein graft-right coronary artery (n = 1). Totally endoscopic coronary artery bypass grafting duration was 254 minutes (range, 178-710 minutes), cardiopulmonary bypass time was 114 minutes (range, 57-428 minutes), and aortic endo-occlusion time was 65 minutes (range, 28-230 minutes).

Results: The postoperative ventilation time was 8 hours (range, 0-278 hours), and the intensive care unit stay was 20 hours (range, 11-389 hours). The postoperative stay at our department was 6 days (range, 4-22 days), and we observed no hospital deaths in this series. Forty-five percent of the patients had an increased postoperative peak creatine kinase MB level, and 75% had an increased troponin T level. Postoperative peak creatine kinase MB levels significantly increased with totally endoscopic coronary artery bypass grafting duration (r = 0.588, P < .001), cardiopulmonary bypass time (r = 0.521, P < .001), and aortic endo-occlusion time (r = 0.400, P < .001) and translated into moderately prolonged intensive care unit stay (r = 0.432, P < .001) and ventilation time (r = 0.517, P < .001). Creatine kinase MB levels were not associated with sex, age, or EuroSCORE. The postoperative left ventricular ejection fraction did not differ significantly from the preoperative left ventricular ejection fraction.

Conclusions: Myocardial protection can be established in arrested heart totally endoscopic coronary artery bypass grafting operations. An influence of increased myocardial enzyme release on postoperative ventilation time and intensive care unit stay is detectable but does not translate into an early mortality or a decrease in left ventricular ejection fraction.