COMPARISON OF THE EFFECT OF MONOPOLAR AND BIPOLAR CAUTERIZATION ON SKELETONIZED, DISSECTED INTERNAL THORACIC ARTERIES

The internal thoracic artery is preferable to the saphenous vein for u se as a conduit for coronary artery bypass, More extensive use is poss ible if this artery is mobilized in a skeletonized form to provide gre ater length, Internal thoracic arteries are usually mobilized with cau terization, This study compared the effectiveness and effects on neigh boring areas of division of the branches of the canine internal thorac ic artery with bipolar cauterization and monopolar cauterization, Bran ch closure was significantly more secure in the bipolar cauterization group, with bleeding in 25 (9%) of 279 branches of 15 internal thoraci c arteries treated with monopolar cauterization, in contrast to bleedi ng in 4 (1.3%) of 306 branches in the 15 internal thoracic arteries tr eated with bipolar cauterization, which were paired with the group tre ated with monopolar cauterization, The group of internal thoracic arte ries treated with monopolar cauterization had a significantly higher p revalence of leakage when luminal pressure was increased from 120 to 1 60 mm Hg. Scanning electron microscopy demonstrated partial loss of en dothelial cells on the how surface of internal thoracic arteries treat ed with bipolar cauterization, compared with almost complete loss of e ndothelial cells around the orificial areas after monopolar cauterizat ion, Secondary bipolar cauterization treatment caused only slightly mo re damage than primary treatment, but secondary monopolar cauterizatio n was much more severe and extensive than primary treatment, These dat a suggest that bipolar cauterization is preferable to monopolar cauter ization for skeletonized dissection of the internal thoracic artery.