This is a method for assembling a prosthetic valved conduit. A kit (1) is provided including:a prosthetic valve (V) having an annular portion (SR)； a prosthetic vascular conduit (40), a collar member (42) including a cuff (420) that is radially contractible to engage the annular portion of the valve (V)； a holder device (2) including a shaft (4) and a hub (12), the prosthetic vascular conduit (40) being fitted on the holder device (2) so that a portion of the conduit (40) adjacent to the cuff (420) wraps around a receiving portion (28) of the hub； The prosthetic heart valve (V) is advanced the into the receiving portion. Then the sleeve member (48) is slid away from the hub (12) to cause the cuff (420) wrap around the annular portion (SR)； eventually securing the cuff (420) is secured around the annular portion (SR) by radially contracting the cuff (V).
