Variable radial stiffness and variable diameter intraluminal device

A radially expandable intraluminal support device for implantation into a lumen of a body vessel having a nominal diameter, the device comprising:

• a first tubular portion having a first end extending to a second end and defining a longitudinal axis therethrough, the first tubular portion comprising at least one ring structure and having a first diameter along a first length of the first tubular portion, the first diameter being greater than the nominal diameter in a fully expanded state, the ring structure of the first tubular portion having a first longitudinal cell length, the first tubular portion having a first radial stiffness;
• a second tubular portion having a third end and extending about the longitudinal axis to a fourth end, the second tubular portion comprising at least one ring structure and having a second diameter along a second length of the second tubular portion, the second diameter in the fully expanded state being substantially equal to the nominal diameter, the ring structure of the second tubular portion having a second longitudinal cell length less than the first longitudinal cell length, the second tubular portion comprising a plurality of second rings disposed coaxial with each other, each second ring individually comprising a plurality of second segments arranged as a plurality of peaks and valleys, adjacent second rings are connected to one another by at least one longitudinal connecting segment, the second tubular portion having a second radial stiffness greater than the first radial stiffness;
• and
• a transition portion between the first tubular portion and the second tubular portion, the transition portion having a length and comprising at least one ring structure and being connected to the second end and the third end, the transition portion having a tapering profile such that the diameter of the transition portion, at any point along its length, has a diameter which is between the first diameter and the second diameter inclusive, the transition portion having a radial stiffness which increases progressively along its length, the radial stiffness of the transition portion increasing from the first radial stiffness at a position at or near the second end to the second radial stiffness at a position at or near the third end;
• wherein the intraluminal support device is of unitary construction, and radial stiffness of the first and second tubular portions is the ability of the first and second tubular portions to resist a compressive force applied perpendicular to an outer surface of the first and second tubular portions.