A system for providing vascular access in a patient's body may comprise at least one hemostatic valve (610) and at least one clamp (210) to be used with a vascular graft (110). The vascular graft (110) comprises a tubular body having a proximal end (110A) and a distal end (110B), the proximal end (110A) being configured to be attached to a vessel in a patient's body. The at least one valve (610) is configured to be attached to the distal end (110B) of the graft's tubular body and comprises a housing (616) including a flexible membrane (611) that allows a medical device (810) to be inserted through the membrane (611) into said vascular graft (110). The valve (610) further comprises an introducer sheath (615) configured to be inserted into the distal end (110B) of the graft's tubular body. The at least one clamp (210) is configured to be disposed around the graft's tubular body and has a first configuration that allows insertion of the valve's introducer sheath (615) into the distal end (110B) of the graft's tubular body and a second configuration that allows clamping of the graft (110) against the valve's introducer sheath (615), when inserted in the graft's tubular body.
