Abstract: A buttress for cardiac valve reconstruction comprises an elongate member formed from two superimposed layers of a fabric. The layers are fastened together by longitudinally extending seams having inwardly extending opposing selvedges. The elongate member fits part-annularly against the base of the cusps of the cardiac valve. The fabric is longitudinally extendable to 105-150% of its non-extended length. An apparatus for cardiac valve reconstruction comprises a holder, including a buttress receiving area; and a buttress comprising a part-annularly shaped elongate member formed from a fabric. The buttress is removably mounted onto the buttress receiving area of the holder in an extended condition, the extended condition being 105-150% of the non-extended length of the elongate member. The buttress and apparatus can be used in the reconstruction of mitral and tricuspid cardiac valves.