Improved cardiac surgery retractor which comprises a baseband formed by a larger base and a smaller base, mutually arranged in a perpendicular manner and forming a cross-section of the baseband in the shape of an L, the smaller base being planar and the larger base having a curved geometry； the baseband incorporating a fin formed by a profile with a cross-section also in the shape of an L and the fin being articulated at the smaller base of the baseband, at a lateral edge of the smaller base contiguous to the contact thereof with the larger base of the same baseband； such that in one position of the joint of the fin, one of the sides of the L profile forming the fin is the continuation of the same smaller base and the other side of the same L profile of the fin is the continuation of the larger base.
