Intraoperative and laboratory evaluation of skeletonized versus pedicled internal thoracic artery

Background. The skeletonization of internal thoracic artery is postulated t o improve graft length early blood flow, sternal blood supply, and postoper ative respiratory function. Concern exists that skeletonization may injure internal thoracic artery, precluding good results of surgery. Reports on en dothelial function of skeletonized internal thoracic artery are lacking. Methods. A prospective assessment of early clinical outcomes of 357 consecu tive patients undergoing coronary artery bypass grafting was performed: 287 patients with nonskeletonized and 70 with skeletonized left internal thora cic artery (LITA). The lengths of LITA and of its discarded distal segment, as well as free LITA blood flow, were measured. The dose-effect relationsh ip for relaxation to acetylcholine was studied in the organ bath. Results. Apart from a higher incidence of breaching the pleura with nonskel etonized LITA the clinical outcomes were comparable. The length of skeleton ized LITA was 17.8 +/- 1.14 cm versus 20.3 +/- 0.52 cm skeletonized (p = 0. 11). The length of discarded LITA was shorter in nonskeletonized artery (0. 8 +/- 0.28 cm versus 2.6 +/- 0.49 cm; p = 0.022). The free LITA blood flow was 66.3 +/- 7.42 mL/min in nonskeletonized vessel versus 100.3 +/- 14.84 m L/min in skeletonized (p = 0.058). The acetylcholine-induced relaxation was similar in both groups (maximal relaxation, 80.7% +/- 5.95% in nonskeleton ized versus 72.9% +/- 9.11% in skeletonized; not significant; negative loga rithm of half-maximal effect, 7.43 +/- 0.18 versus 7.1 +/- 0.10, respective ly; p = 0.063). Conclusions. Skeletonization does not damage the endothelial function of th e LITA. Higher free blood flow and available LITA length should encourage t he use of skeletonized LITA in clinical practice. (C) 1999 by The Society o f Thoracic Surgeons.