Transcatheter prosthetic heart valve delivery system and method with expandable stability tube

A system for restoring a defective heart valve of a patient, the system comprising:

• a prosthetic heart valve including a stent frame and a valve structure attached to the frame and forming at least two valve leaflets, the prosthetic heart valve being radially self-expandable from a compressed arrangement to a normal, expanded arrangement;
• and a delivery device comprising:
• an inner shaft assembly including a coupling structure configured to selectively engage the prosthetic heart valve,
• a delivery sheath assembly slidably disposed over the inner shaft assembly and including a distal capsule and a proximal shaft, wherein the capsule is configured to compressively contain the prosthetic heart valve in the compressed arrangement, the capsule having a greater outer diameter than an outer diameter of the proximal shaft,
• an outer stability tube slidably disposed over the delivery sheath assembly, the stability tube including a tubular proximal region and a tubular distal region having a length, the distal region including a polymer tubular wall having a plurality of cuts formed through a thickness of the polymer tubular wall, the plurality of cuts having a length less than the length of the distal region, the distal region configured to be radially expandable by plastic deformation from a first shape having a first diameter to a second shape having a second diameter, the second diameter being greater than the first diameter, the stability tube self-maintaining the second shape by plastic deformation without support of external forces,
• a handle including a housing maintaining the inner shaft assembly, the delivery sheath assembly and the tubular proximal region of the stability tube, the handle being operable to selectively move the delivery sheath assembly relative to the inner shaft assembly and the stability tube;
• wherein the system is configured to provide a delivery condition in which the capsule compressively contains the prosthetic heart valve in the compressed arrangement over the inner shaft assembly, and a deployed condition in which the capsule is retracted from the prosthetic heart valve and at least partially into the distal region to permit the prosthetic heart valve to self-deploy toward the normal expanded arrangement and release from the delivery device.