Patent ID: 6945990

Claim:
A stent-graft deployment system, comprising: a stent-graft; a catheter, comprising: a catheter shaft having a tip; a retractable primary sheath and a retractable flexible secondary sheath, wherein the primary sheath is disposed about the secondary sheath; wherein in a predeployed condition said stent-graft is contained within the flexible secondary sheath and retained in a first constrained small diameter configuration by the primary sheath, wherein when said primary sheath is retracted from around said stent-graft, said flexible secondary sheath retains said stent-graft in a second constrained small diameter configuration larger than said first constrained small diameter configuration and has substantially reduced resistance to bending as compared to when said primary sheath is covering said stent-graft, wherein removal of the secondary sheath releases the stent-graft from a radial constraint so that stent-graft deployment occurs as the secondary sheath releases.