Stent having a multiplicity of closed circular structures

Claim 2

The stent of Claim 1, wherein the longitudinals (14) comprise a pair of top and bottom longitudinals and a pair of side longitudinals, the top and bottom longitudinals being adapted to maintain an essentially unchanged shape in the absence of the multiplicity of generally circular rings, and the side longitudinals having said undulating shape.

Claim 3

The stent of Claim 1 or Claim 2, wherein the longitudinals (14) are of unitary construction with the generally circular rings (12) from a single piece of thin-walled metal tubing.

Claim 4

The stent of Claim 1 or Claim 2, wherein the rings (12) have a multiplicity of cutouts (5) for the placement therethrough of the longitudinals (14), the longitudinals being generally elongated structures that lie parallel to the common longitudinal axis of the generally circular rings (12).

Claim 5

The stent of claim 4, wherein the cutouts (5) on the rings are formed in unitary construction with the longitudinals (14) from a single piece of metal.

Claim 6

The stent of claim 5, wherein the single piece of metal is generally in the form of a thin-walled cylinder.

Claim 7

The stent of claim 1, wherein at least one of the longitudinals (14) is spaced apart from all other longitudinals (14).

Claim 8

The stent of claim 1, wherein each longitudinal (14) is spaced apart from every other longitudinal (14).

Claim 9

The stent of claim 1, wherein at least one of the longitudinals (14) is a linearly directed, elongated structure.

Claim 10

The stent of claim 1, wherein the rings (12) and longitudinals (14) are made from titanium.

Claim 11

The stent of claim 1, wherein the multiplicity of circular rings (12) has exactly two end rings which are those rings which have an adjacent ring on only one side and at least one interior ring which has adjacent rings on both sides, at least some portion of the end rings being formed from a metal having a higher density as compared to the density of the metal of the at least one interior ring.

Claim 12

The stent of claim 1, wherein the stent is formed from a metal having a shape memory characteristic.

Claim 13

An initial structure (1') that is capable of being formed into a pre-deployment stent structure which in turn is capable of being deployed into a post-deployment stent structure as claimed in any preceding claim for placement within a vessel of the human body, the initial structure being characterised by: a multiplicity of flat ovals (2') which in the post-deployment stent form said multiplicity of closed, generally circular rings (12), the plane of each oval being generally parallel to the plane of all other ovals, the ovals having a common longitudinal axis which is perpendicular to the plane of each oval and which longitudinal axis passes through the geometric centre of the ovals; and a multiplicity of longitudinals (14) fixedly attached to the ovals (2'), at least two of the longitudinals having an undulating shape so as to enhance longitudinal flexibility, the longitudinals being positioned onto the ovals so as to be generally parallel to the longitudinal axis of the ovals, at least one of the longitudinals being spaced apart from all other longitudinals.

Claim 14

The initial structure of claim 13 wherein the ovals (2') and the longitudinals (14) are unitary.

Claim 15

A pre-deployment stent structure (20) which is capable of being deployed into a post-deployment stent structure as claimed in any of claims 1 to 12 for placement within a vessel of the human body, the pre-deployment structure being formed from an initial structure being characterised in that the initial structure consists of a multiplicity of flat ovals which in the post-deployment stent form said multiplicity of closed, generally circular rings (12), the plane of each oval of said initial structure being generally parallel to the plane of all other ovals, the ovals also having a minor axis and a major axis and a minor axis dimension and a major axis dimension, the ovals having a common longitudinal axis which is perpendicular to the plane of each oval and which longitudinal axis passes through the geometric centre of the ovals, and a multiplicity of longitudinals fixedly attached to the ovals, the longitudinals being positioned onto the ovals from a single metallic structure, at least two of the longitudinals having an undulating shape so as to enhance longitudinal flexibility, and the pre-deployment stent structure being formed by folding the ovals about each oval's minor axis in nested relation each with respect to the other, the pre-deployment stent structure being adapted to form a post-deployment stent structure having a multiplicity of generally circular rings that are formed from the ovals.

Claim 16

The pre-deployment stent structure of claim 15 wherein the ovals (2') are folded around an expandable balloon (6) located near the distal end of a stent delivery catheter.

Claim 17

The pre-deployment stent structure of claim 15 wherein the ovals (2') are folded around the oval's minor axis to form a pre-deployment structure of a generally cylindrical shape that can be mounted onto a stent delivery catheter.

Claim 18

The pre-deployment stent structure of claim 15 wherein one side of the ovals (2') is folded in one direction and the opposite side of the ovals is folded in the opposite direction to form a pre-deployment structure of a generally cylindrical shape.

Claim 19

The pre-deployment stent structure of claim 15, wherein the outer diameter of the generally cylindrical pre-deployment stent structure is approximately the same as the minor axis dimension of the oval (2').

Claim 20

The pre-deployment stent structure of claim 17, wherein the stent structure formed from the single metallic structure is a cylinder that is smaller in its inside diameter as compared to the outside diameter of an expandable balloon (6) located at a distal portion of a stent delivery catheter onto which the stent structure is mounted.

Claim 21

The pre-deployment stent structure of any of claims 15 to 20, wherein said at least two longitudinals having an undulating shape (14L,14R) comprise a multiplicity of straight sections and undulating sections with each straight section being joined continuously to an undulating section, the straight sections of all of the longitudinal structures being generally parallel to the longitudinal axis of the stent, the undulating sections of each longitudinal structure being of a generally curved shape so as to allow each undulating longitudinal structure to readily expand and contract in length during insertion of the stent in to a curved vessel.

Claim 22

The pre-deployment stent structure of claim 21, wherein each undulating section is in the general form of a sine wave.