A surgical instrument for holding a piece of tissue in a configuration of an open circulatory system valve to facilitate surgical attachment of the tissue to the patient's valve annulus. The instrument includes an inner member having a handle portion at one end and an inner tissue holding portion at the opposite end. The inner tissue holding portion includes one or more of inner leaves. An outer member disposed about the inner member includes an outer tissue holding portion having one or more of outer leaves that are complementary and can be engaged with the inner leaves. A collet or other actuator moves the outer leaves radially inward and outward with respect to the inner leaves. The outer leaves are separated from the inner leaves to allow placement of the tissue on the inner leaves. The outer leaves are then moved radially inward to hold the tissue between the leaves in a configuration of one or more leaflets of an open circulatory system valve to facilitate surgical attachment.