A hemostasis valve device intended for inserting a medical material into a patient, of the type comprising: - a hollow body delimiting an inner passage for inserting the material extending between a proximal opening and a distal opening; - a sealing valve, positioned in the inner passage, the sealing valve having at least one central passage that is sealed when idle; - a member for opening the central passage of the valve, movable relative to the body between an idle position, in which the valve is sealed, and an open position of the valve; - an assembly for maintaining the material in position in the inner passage of the body, the maintaining assembly including: - a radially compressible member positioned in the inner passage, the compressible member delimiting, when idle, a through passage aperture of the material; - at least one radial compression member for radially compressing the compressible member, radially movable relative to an axis of the passage aperture to outwardly compress the compressible member; - a member for actuating the or each compression member, movable relative to the body to cause the compression member to go from a radially retracted position, in which the section of the passage aperture is maximal, to a position that is radially deployed in the compressible member, in which the section of the passage aperture is minimal. characterized in that each radial compression member is formed by a jaw that is radially movable relative to the body between an idle retracted position and a position that is deployed radially toward the longitudinal axis (A-A') of the body, each jaw being inserted through a distal window of the body and being guided in radial translation toward the longitudinal axis (A-A') in the window between the idle retracted position and the radially deployed position, each jaw having an external radial surface intended to cooperate with the actuating member, and an internal radial surface intended to be applied to the compressible member, the device comprising at least two opposite compression members, the actuating member being capable of simultaneously moving the compression members from their radially retracted position toward their radially deployed position. - a hollow body delimiting an inner passage for inserting the material extending between a proximal opening and a distal opening; - a sealing valve, positioned in the inner passage, the sealing valve having at least one central passage that is sealed when idle; - a member for opening the central passage of the valve, movable relative to the body between an idle position, in which the valve is sealed, and an open position of the valve; - an assembly for maintaining the material in position in the inner passage of the body, the maintaining assembly including: - a radially compressible member positioned in the inner passage, the compressible member delimiting, when idle, a through passage aperture of the material; - at least one radial compression member for radially compressing the compressible member, radially movable relative to an axis of the passage aperture to outwardly compress the compressible member; - a member for actuating the or each compression member, movable relative to the body to cause the compression member to go from a radially retracted position, in which the section of the passage aperture is maximal, to a position that is radially deployed in the compressible member, in which the section of the passage aperture is minimal.