Is skeletonized internal mammary harvesting better than pedicled harvesting in respect of the sternal blood flow?: an estimation using bone scan

초록

Objective: A study using bone scan is designed to determine whether the difference in internal mammary artery harvesting techniques effects on the sternal blood flow. Methods: From April 2002 to March 2003, 27 patients were enrolled into the study out of 48 patients who underwent the isolated coronary bypass surgery. The enrolled patients underwent bone scan in the preoperative period and postoperative period respectively. The patients were divided into three groups: those in whom bilateral internal mammary arteries were used regardless of harvesting technique (BIMA group, n=8), those in whom skeletonized left internal mammary artery was used (LIMA_skel group, n=12), and those in whom pedicled left internal mammary artery was used (LIMA_ped group, n=7). After the bone scan, the region of interest (ROI) was created on the left half of the sternum and the mirror image with the same pixel numbers was placed on the right half of the sternum. The mean counts per pixel on the left side of the sternum was compared with those on the right side and expressed as left to right ratio (L/R ratio). Results: In LIMA group, the L/R ratio decreased from 94.6±4.1% to 87.9±6.9% (p=0.003) after the operation as compared to BIMA group, in which no change of the L/R ratio was observed. The changes of the L/R ratio in LIMA_skel group and LIMA_ped group were from 95.3±4.2% to 88.3±7.7% and from 93.4±3.9% to 87.4±5.8% respectively. The %changes of the L/R ratio were -7.44±7.08 in LIMA_skel group and -6.17±9.08, which did not reach the statistical difference. Conclusions: Ipsilateral sternal blood flow is interrupted by internal mammary artery harvesting as evidenced by decrease of the L/R ratio after left internal mammary artery harvesting irrespective of the harvesting techniques. Skeletonized harvesting could not show superiority in respect of sternal blood flow as compared to pedicled harvesting.