Comparative Study of Two Brands of Heparin Already on the Market

Two heparin brands have been in the market in Canada for several years. Heparin Leo from Leo Pharma and Hepalean from Organon. The former is standardized by B.P (British pharmacopeia) while the latter is standardized by U.S.P (United states pharmacopeia). Previous studies have shown Heparin Leo to have roughly a 10% less efficacy then Hepalean. It has also been demonstrated that more protamine is required to reverse Heparin Leo. It is the investigators' intention to study the post-operative effects of the two brands of heparin and whether one of the two causes less bleeding after bypass surgery.