Longitudinally flexible stent

摘要

An intravascular stent especially suited for implanting in curved arterial portion. The stent retains longitudinal flexibility after expansion. The stent is formed of intertwined meander patterns forming triangular cells. The cells are adapted to provide radial support, and also provide longitudinal flexibility after expansion. The cells also provide increase coverage of a vessel wall. Loops in the stent are disposed and adapted to cooperate, so that after expansion of said stent within a curved lumen, the stent is curved and cells on the outside of the curve open in length, but narrow in width, whereas cells on the inside of the curve shorten in length, but thicken in width to maintain a density of the stent element area which is much more constant than otherwise between the inside and outside of the curve. The stent also minimizes flaring out by eliminating free loops of the radially supporting circumferential bands of loops. The stent includes widened struts, wherein one or more of the widened struts have at least one reservoir for the delivery of an agent to a vessel site. The reservoir may be a fenestration or a recess that opens towards either the vessel wall or the lumen.

主权项

1. A stent comprising:
a plurality of first sinusoidal bands having strut members connected by curved segments, said first sinusoidal bands arranged generally in a circumferential direction, said curved segments occurring at a first frequency, at least one of said curved segments forming a keyhole-like structure with the adjacent strut members, and a plurality of second sinusoidal bands having strut members connected by curved segments, said curved segments in said second loop containing sections occurring at a second frequency that is higher than said first frequency, said second sinusoidal bands consecutively alternating with said first sinusoidal bands along a longitudinal axis of the stent; wherein at least one curved segment of a first sinusoidal band has a greater width than the width of the strut members of a second sinusoidal band; and wherein said first and second sinusoidal bands connect directly at curved segments of said first and second sinusoidal bands to form a plurality of cells.