Novel method to enhance sternal healing after harvesting bilateral internal thoracic arteries with use of basic fibroblast growth factor

Background-Poor healing of the sternum often limits the use of bilateral in ternal thoracic arteries (BITAs) in coronary bypass surgery, especially for diabetic patients. We have reported that basic fibroblast growth factor (b FGF) enhanced regeneration of the skull. This study was designed to evaluat e the effects of topical use of bFGF on sternal healing after removing the BITAs. Methods nod Results-Forty-five Wistar rats were subjected to median sternot omy and were divided into 3 groups: 15 had the BITAs removed and had a bFGF sheet applied on the posterior table of the sternum (group A), 15 had just the BITAs removed (group B), and 15 had intact BITAs (group C), Five and 1 0 rats were euthanized 2 and 4 weeks after surgery, respectively, in all 3 groups. Peristernal blood flow, measured with use of a noncontact laser flo wmeter, decreased after removal of the BITAs (P<0.001). Four weeks after th e surgery, PBF markedly increased only in group A (9.7+/-1.2, 6.5+/-0.6, an d 8.2+/-0.5 mL.min(-1).100 g(-1) for groups A, B, and C, respectively; P<0. 01 by ANOVA). Four weeks after surgery, the following findings were obtaine d only in group A: (1) nearly completely healed sternum filled with regener ated bone tissue, (2) marked angiogenesis around the sternum, and (3) osteo blasts in an active form around the edge of the sternum. Conclusion-The results suggest that use of the bFGF sheet offset the sterna l ischemia and accelerated sternal healing. This method may help to decreas e sternal necrosis in high-risk patients or allow extended use of BITAs in coronary bypass surgery.