Balloon catheter having multiple inflation lumens and related methods

Abstract

An apparatus is for performing a medical procedure using an inflation fluid. The apparatus includes a shaft with two inflation lumens for transmitting the inflation fluid. A balloon supported by the shaft has an interior capable of being inflated by the inflation fluid transmitted through the inflation lumens of the shaft. The tubes defining the inflation lumens provide two outlets for transmitting different flows of the inflation fluid to the interior of the balloon. A stent and related methods are also disclosed.

Claims

1. An apparatus comprising: an inflatable balloon having proximal and distal cones and an interior for receiving inflation fluid; a first tube comprising a first inflation lumen with a first outlet for transmitting a first flow of the inflation fluid to the interior of the balloon; and a second tube inside the balloon having a proximal end, a distal end, a second outlet spaced from the first outlet in a longitudinal direction, and a passage between the proximal and distal ends adapted to transfer inflation fluid to the second outlet for inflating the balloon; wherein the proximal end is located within the proximal balloon cone and the distal end is located within a distal balloon cone.

2. The apparatus of claim 1 wherein the balloon comprises any one or any combination of a therapeutic agent, a stent, or a stent graft.

3. The apparatus of claim 2 further comprising a stent or stent graft disposed on the balloon, and wherein the first tube supplies inflation fluid to the proximal cone and to the second tube, and the second tube supplies inflation fluid to the distal cone.

4. The apparatus according to claim 3 wherein the proximal end spaced from the first outlet and the second tube is longer than the stent or stent graft.

5. The apparatus according to claim 4 wherein the second tube has a wall thickness in the range of 0.0005 inches to 0.0025 inches.

6. The apparatus according to claim 5 wherein the balloon further comprises a barrel between the proximal and distal cones, and the proximal end is spaced from the first outlet and a length of the second tube is greater than or equal to a length of the barrel.

7. The apparatus according to claim 6 wherein the first outlet is located proximally of the balloon distal cone.

8. The apparatus of claim 7 further comprising a guidewire tube, wherein the guidewire tube supports both the first tube and the second tube within the balloon.

9. The apparatus of claim 8 wherein the first tube extends into the balloon beyond a point at which the balloon is attached to a catheter shaft forming the tube.

10. The apparatus of claim 1 further comprising a stent or stent graft disposed on the balloon, and wherein the first tube supplies inflation fluid to the proximal cone and to the second tube, and the second tube supplies inflation fluid to the distal cone.

11. The apparatus according to claim 1 further comprising a stent or stent graft disposed on the balloon, and wherein the second tube has a first proximal end spaced from the first outlet, and the second tube is longer than the stent or stent graft.

12. The apparatus according to claim 11 wherein the second tube has a wall thickness in the range of 0.0005 inches to 0.0025 inches.

13. The apparatus according to claim 12 wherein the balloon further comprises a barrel between the proximal and distal cones, and the proximal end is spaced from the first outlet and a length of the second tube is greater than or equal to a length of the barrel.

14. The apparatus according to claim 13 wherein the first outlet is located proximally of the balloon distal cone.

15. The apparatus of claim 14 further comprising a guidewire tube, wherein the guidewire tube supports both the first tube and the second tube within the balloon.

16. The apparatus of claim 15 wherein the first tube extends into the balloon beyond a point at which the balloon is attached to a catheter shaft forming the tube.

17. An apparatus comprising: an inflatable balloon having proximal and distal cones and an interior for receiving inflation fluid; a first tube comprising a first inflation lumen with a first outlet for transmitting a first flow of the inflation fluid to the interior of the balloon; a second tube inside the balloon having a proximal end, a distal end, and a solid wall defining a passage between the proximal and distal ends; and a guidewire tube, wherein the guidewire tube supports both the first tube and the second tube within the balloon.

18. An apparatus comprising: an inflatable balloon having proximal and distal cones, proximal and distal necks, and an interior for receiving inflation fluid; a first tube comprising a first inflation lumen with a first outlet for transmitting a first flow of the inflation fluid to the interior of the balloon; and a second tube inside the balloon having a proximal end, a distal end, a solid wall defining a passage between the proximal and distal ends, and a second outlet spaced proximally of the distal neck; wherein the balloon further comprises a barrel between the proximal and distal cones, the proximal end of the second tube is spaced from the first outlet, and a length of the second tube is greater than or equal to a length of the barrel; wherein the proximal end is located within the proximal balloon cone or the proximal balloon neck.

Description

BRIEF DESCRIPTION OF THE DRAWING FIGURES

(1) FIG. 1 is a partially cutaway side view of a balloon catheter according to one aspect of the disclosure;

(2) FIG. 2 is a partially cutaway perspective view of a balloon catheter according to the disclosure;

(3) FIGS. 2a, 2b, and 2c are cross-sectional views taken along lines 2a-2a, 2b-2b, and 2c-2c of FIG. 2;

(4) FIG. 3 is a partially cutaway side view of a balloon catheter according to the disclosure;

(5) FIG. 3a is cross-sectional view taken along lines 3a-3a of FIG. 3;

(6) FIGS. 3b and 3c are cross-sectional views illustrating one embodiment, taken along lines 3b-3b and 3c-3c of FIG. 3;

(7) FIGS. 3d and 3e are cross-sectional views illustrating one embodiment, taken along lines 3d-3d and 3e-3e of FIG. 3;

(8) FIG. 4 a partially cutaway perspective view of a balloon catheter according to the disclosure, with the balloon in an expanded condition;

(9) FIG. 5 is a cross-sectional view taken along line 5-5 of FIG. 4;

(10) FIG. 6 is a partially cutaway perspective view of a balloon catheter according to the disclosure, with the balloon in a folded condition;

(11) FIG. 7 is an enlarged side view of a stent device forming another aspect of the disclosure;

(12) FIG. 8 is another side view of the stent device; and

(13) FIG. 9 is an enlarged side view of the stent device.

MODES FOR CARRYING OUT THE INVENTION

(14) The description provided below and in regard to the figures applies to all embodiments unless noted otherwise, and features common to each embodiment are similarly shown and numbered.

(15) Referring now to FIG. 1, an apparatus according to one aspect of the disclosure comprises a catheter 10 including an inflatable balloon 12. The balloon 12 may be mounted adjacent to a distal end of a catheter shaft in the form of a tube 14, and hence is supported thereby (even though the balloon 12 might not be directly affixed to the tube 14). A proximal end 12a and a distal end 12b of the balloon 12 may be in the form of tapered or generally conical sections or cones N separated by a generally cylindrical body section, or barrel B. Balloon 12 may include a single or multi-layered balloon wall forming the interior for receiving the inflation fluid.

(16) The balloon 12 may be made from typical materials including polymers such as polyethylene terephthalate (PET), polyetherimide (PEI), polyethylene (PE), polytetrafluoroethylene (PTFE), expanded polytetrafluoroethylene (ePTFE), ethylene tetrafluoroethylene (ETFE), fluorinated ethylene propylene (FEP), polyoxymethylene (POM), polybutylene terephthalate (PBT), polyether block ester, polyurethane, polypropylene (PP), polyvinylchloride (PVC), poly ether-ester, polyester, polyamide, elastomeric polyamides, block polyamide/ethers, polyether block amide, silicones, Marlex high-density polyethylene, Marlex low-density polyethylene, linear low density polyethylene, polyetheretherketone (PEEK), polyimide (PI), polyphenylene sulfide (PPS), polyphenylene oxide (PPO), polysulfone, nylon, perfluoro (propyl vinyl ether) (PFA), other suitable materials, or mixtures, combinations, copolymers thereof, polymer/metal composites, and the like. The wall thickness of the balloon 12 may vary depending on the burst pressure requirements and hoop strength of the balloon material. Fibers, rods, or other types of reinforcement structures may also be included along, within, or as part of the balloon wall, which may also be provided with radiopaque qualities to allow for visualization under fluoroscopy.

(17) The balloon 12 may be non-compliant, having a balloon wall that maintains its size and shape in one or more directions when the balloon is inflated for applying a treatment, including possibly drug or an expandable endoprosthesis (e.g., a stent S, stent graft, or similar implant device) for being positioned or deployed with the aid of catheter 10. In the case of a stent S, expansion of the balloon 12 may also result in expansion of the stent for delivery in the associated vessel or other body lumen. The stent S may be at least partially constructed of any of a variety of materials, such as stainless steel, nickel, titanium, nitinol, platinum, gold, chrome, cobalt, as well as any other metals and their combinations or alloys. In some embodiments, a stent may be at least partially constructed of a polymer material, such as a shape-memory polymer. In some embodiments, the balloon 12 or the implant carried by it may include one or more therapeutic and/or lubricious coatings.

(18) The balloon 12 may also have a surface area that remains constant during and after inflation. The balloon 12 may also have a pre-determined length and pre-determined diameter that remain constant during and after inflation. However, the balloon 12 could be semi-compliant or compliant instead, depending on the particular use to which it is put.

(19) The tube 14 serving as the catheter shaft includes a lumen 16 forming a conduit for supplying an inflation fluid (e.g, saline, with or without a contrast agent) from a remote source (such as an inflation device, not shown) to the balloon 12. As illustrated in FIG. 1, this inflation lumen 16 supplies the fluid to the balloon 12 via two distinct passages, thus creating independent fluid flows for inflating different portions of the balloon 12. For example, the fluid delivery may be through a first lumen 16a for delivering a first portion of the flow, and a second, distinct lumen 16b for delivering a second portion of the flow.

(20) Each lumen 16a, 16b may be provided at a different location relative to the interior of the balloon 12. Specifically, the first lumen 16a may be formed by a first tube 18a having an outlet O.sub.1 positioned at a proximal end 12a of the balloon interior I, such as adjacent to the proximal cone N when the balloon is inflated. The second lumen 16b may be formed by a second tube 18b include an outlet O.sub.2 may be positioned at a distal end 12b of the balloon 12, adjacent to a second, distal cone N. It can be understood that the term tube is used herein to refer to a distinct structure comprising an outer wall with an inner surface forming a conduit or lumen having an inlet and outlet, and not merely a lumen within a structure.

(21) One or both the first and second tubes 18a, 18b may be attached to the tube 14 forming the catheter shaft, or may be separate therefrom. The tube 14 may also include a guidewire lumen 22 arranged for allowing a guidewire G to pass (which may be introduced in an over the wire (OTW) or rapid exchange (RX) configuration). In either case, the guidewire lumen 22 extends fully from the proximal end 12a to a tip P adjacent the distal end 12b of the balloon 12. The guidewire lumen 22 may be provided by a smaller diameter tube 14a forming an extension or part of the tube 14 extending within the balloon interior I, which tube 14a may extend to the proximal end of the catheter 10 as well to a hub (not shown).

(22) In one particular embodiment, as shown in FIG. 2, the catheter 10 includes a coaxial arrangement. In such an arrangement, the guidewire lumen 22 is coaxial with at least part of the inflation lumen 16 in at least the portion of the tube 14 proximal of the balloon 12 (see FIG. 2a). In this approach, a divider, such as a transverse partition 24, may be provided adjacent to (e.g., proximal of) the inlet of the dual inflation lumens 16a, 16b, and may associate with tubes 18a, 18b for transmitting flows of the inflation fluid (see FIG. 2b). Consequently, the fluid flow to the balloon 12 is divided, and enters the balloon interior I by way of a first flow F.sub.1 through one lumen 16a at a first location corresponding to the outlet O.sub.1 closer to the proximal end 12a and a second flow F.sub.2 through another lumen 16b at a second location corresponding to the outlet O.sub.2 closer to the distal end 12b (and in a side-by-side arrangement with the portion of tube 14 forming the guidewire lumen 22, see FIG. 2c).

(23) As can be appreciated, the inflation fluid may thus be supplied in different flows to different parts of the balloon 12 in a strategic manner by selecting the length and diameter of the different tubes 18a, 18b. This allows for the relative inflation of the balloon 12 to be precisely controlled, unlike in arrangements where the fluid may enter the balloon at either the proximal end or distal end. Such precision control may help to avoid the differential inflation characteristics that result in misplacement or misalignment of a corresponding payload, such as a stent, stent graft, or other treatment, carried thereon.

(24) In one embodiment, as shown in FIG. 3, the catheter 10 with multiple inflation passages for delivering flows of the inflation fluid to the balloon 12 is a dual lumen configuration. The catheter tube 14 thus includes a guidewire lumen 22 (which may extend though the entire balloon 12) and a separate inflation lumen 16. This inflation lumen 16 (which is shown in FIG. 3a as having an oblong curved or crescent shape in a transverse direction when viewed in cross-section) may also separate into two or more inflation lumens 16a, 16b. This division may occur at a transition T created by a divider, such as the transverse partition 24 within the inflation lumen 16 located proximally of the proximal end 12a of the balloon 12. Hence, the flow of the inflation fluid may be divided prior to entering the interior of the balloon 12.

(25) While FIG. 3 illustrates a single catheter 10, the arrangement of the dual lumens 16a, 16b may be different in different embodiments, as shown in the cross-sections. For example, in one embodiment, as shown in FIGS. 3b and 3c, two separate tubes 18a, 18b create the dual inflation lumens 16a, 16b, and are supported within the balloon 12 along the external surface of the tube 14a forming the guidewire lumen 22. In another, as shown in FIGS. 3d and 3e, a first lumen 16a is provided adjacent the proximal end of the transition T (such as by simply forming a hole in the structure serving as partition 24), and the other lumen 16b corresponds to a separate tube 18b that extends into and at least partially through the interior I of the balloon 12. As can be appreciated, the length of the portion of the tube or tubes 18a, 18b within the balloon 12 may be less than the length D of the balloon 12 in the longitudinal direction (which balloon length D may be considered herein the distance between the end of the cone N at the distal end 12b, and the end of the cone N at the proximal end 12a).

(26) As should be appreciated, the ability to provide multiple inflation lumens 16a, 16b comprising different sizes or lengths of tubes 18a, 18b, allows for the inflation of the balloon 12 to be controlled in an optimal manner. Specifically, the locations of the outlets O.sub.1, O.sub.2 may be selected to correspond to the desired inflation profile, which in most cases involves inflating the proximal and distal cones N of the balloon 12 at a substantially equal rate using different flows of fluid so as to ensure the proper deployment of an expandable implant, such as a stent or stent graft (if present), or the even application of a treatment, such as a drug. In the dual lumen embodiment, a single inflation lumen 16b may extend to the cone N at the distal end 12b of the balloon 12, while the outlet of the proximal inflation lumen 16a may simply be provided at a transition T without extending into the interior of the balloon 12. Consequently, a lower profile catheter 10 may be provided. Furthermore, the materials of the corresponding tubes 18a, 18b may be selected to provide different characteristics in terms of flexibility and strength.

(27) The relative diameters of the lumens 16a, 16b may also be selected to control the relative amount of the inflation fluid delivered to different interior portions of the balloon 12. For example, a larger diameter tube 18b may be used to deliver the inflation fluid to the distal end 12b, while a slightly smaller tube 18a may be used to deliver the inflation fluid to the proximal end 12a, thus accounting for the pressure differential created as a result of the additional travel distance. Likewise, varying the length of one or both of the tubes 18a, 18b allows for precision control of the location of the corresponding outlets O.sub.1, O.sub.2, which means that the inflation fluid upon exiting may create a more pronounced effect at corresponding locations of the balloon 12 (such as within the cones N at the proximal and distal ends 12a, 12b of the balloon 12 to help prevent the undesirable condition of watermelon seeding mentioned in the foregoing discussion). As a consequence of this multi-level, enhanced adaptability, an optimal inflation profile may be provided, which may help to avoid the problems created by differential inflation, especially when the balloon carries a treatment, such as a stent, stent graft, drug, or any combination of the foregoing.

(28) While the use of one or two tubes 18a, 18b is illustrated, more than two tubes may be used while achieving the desired objective of substantially even inflation. For example, a third tube may be provided for delivering inflation fluid to the middle cylindrical section, or barrel B, of the balloon 12. Likewise, pairs of tubes may be provided for delivering the inflation fluid to the balloon interior I, such as at or near the proximal and distal cones N.

(29) FIG. 4 shows a catheter 10 also including an expandable endoprosthesis, such as a stent S or stent graft having a length E length less than the balloon length D. FIG. 5 is a cross-sectional view showing one possible construction of the tube 14 to include an inflation lumen 16, as well as a guidewire lumen 22 formed by tube 14a extending fully from the proximal end 12a to the tip P adjacent to the distal end 12b of the balloon 12. The inflation lumen 16 opens into the proximal end 12a of the balloon 12, which may be connected to the tube 14 forming the catheter shaft at the proximal end 12a and to the tip P receiving the guidewire lumen 22 at the distal end 12b.

(30) With combined reference to FIGS. 4 and 6, it can be understood that a conduit 30 for transmitting the inflation fluid (e.g., contrast media) is provided within the balloon 12 over the guidewire lumen 22, which is partially shown in phantom. Hence, the inflation lumen fined between the inner surface of the tube forming the conduit 30 and the tube forming the guidewire lumen 22 may be annular. Consequently, when the stent or other implant is in a compressed or unexpanded condition (S) on a folded balloon (12), fluid is able to flow into the conduit 30 from the inlet opening adjacent to the proximal end 12a of the balloon 12, and to the outlet opening adjacent to the distal end 12b. As such, the mounted stent S remains stationary on the balloon 12 throughout insertion and inflation, and the watermelon seeding condition may be avoided.

(31) The conduit 30 may be a thin-walled tube positioned along the guidewire lumen 22, and may be positioned over the corresponding portion of the tube 14 forming at least part of the guidewire lumen as illustrated. In this particular embodiment, the conduit 30 and the guidewire lumen 22 are co-axial, but it should be appreciated that the conduit could take the form of an auxiliary tube carried on the tube 14 within the balloon 12 in a non-coaxial or side-by-side configuration as well. It can also be appreciated from the illustrated embodiment that the conduit 30 is not directly connected to the inflation lumen 16, which may terminate at the end of the tube 14 forming catheter shaft adjacent to the proximal end 12a of the balloon 12. The conduit 30 thus includes an open end or inlet closer to or at the proximal end 12a of the balloon 12, and may further include an open end or outlet closer to or at the distal end 12b of the balloon 12.

(32) The wall thickness of the thin-walled tube forming the conduit 30 in one embodiment is in the range of about 0.0005 inches to about 0.0025 inches, and may be about 0.0015 inches. As can be appreciated, positioning the thin-walled tube or conduit over tube 14 including the guidewire lumen 22 to which the balloon 12 is attached at a proximal end 12a and distal end 12b, enables the concurrent inflation of both distal and proximal balloon cones N, preventing the implant (e.g., stent S) from migrating. The conduit 30 may be used on a wide variety of existing catheter assemblies to provide a balloon catheter 10 with an improved inflation mechanism as compared with the case where a single flow of inflation fluid is used.

(33) The conduit 30 may be coupled to the portion of the portion of the tube 14 forming the guidewire lumen 22 within the balloon 12 in any of a number of suitable ways. For example, in one embodiment, the conduit 30 may be free-floating over the guidewire lumen 22, such that it essentially becomes slidable along it in both directions along a longitudinal axis. In another embodiment, the conduit 30 is attached at one or more points along an outer surface of the tube 14 forming the guidewire lumen 22, whether co-axial or not.

(34) In the co-axial configuration, the conduit 30 may have an internal dimension slightly greater than an outer dimension of the guidewire lumen 22 or tube 14a over which it is disposed. In one possible embodiment, the difference between the inner diameter of the conduit 30 and the outer diameter of the tube 14a is 0.008 inches. This configuration enables the inflation fluid to flow through the crimped stent S without affecting the profile of the balloon 12 in a significant way (at least until sufficient pressure is created to cause expansion).

(35) The length of the conduit 30 may vary, and may be longer than the length of the body section or barrel B between the cones N at the proximal and distal ends 12a, 12b. In such case, the conduit 30 on both proximal and distal ends thereof extends, respectively, into the proximal and distal cones N (and possibly to a point of interface with the inflation lumen, but in the illustrated embodiment the two structures are spaced apart in the longitudinal direction). Considering that each of the proximal and distal cones N has a length, in one embodiment, the conduit 30 is of sufficient length to extend into each of the proximal and distal cones to approximately the mid-point of the length of the proximal and distal cones. It should be appreciated that the length of the conduit 30 may be greater than the length E of the implement, such as stent S, disposed over the balloon 12, but less than the length D of the balloon 12 itself. As a result of the compression or crimping of a stent S onto the balloon 12, the ends of the conduit 30 beyond the perimeter of the stent S may tend to flare outwardly, which flared ends further help to provide a stent retention function during insertion and prior to deployment. However, expansion of the balloon 12 removes the compressive force, and thus the ends of the conduit 30 return to normal and do not cause any hang-up that would preclude proper deployment of the stent S.

(36) FIGS. 7-9 illustrate a stent 100 with a stent architecture including v-shaped stent elements v.sub.1-v.sub.4, each of which include a first leg portion parallel to the longitudinal axis L, a peak portion, and a second leg portion angled with respect to the longitudinal axis, and V-shaped stent elements V.sub.1-V.sub.2. Beginning from the top left side of FIG. 7, a repeating series of stent elements is shown along a first side 66 of the stent cells 62 and 64. The v-shaped stent elements v.sub.1, v.sub.2, v.sub.3, v.sub.4 are similar in shape but are oriented differently from one another with respect to a circumferential axis and/or a longitudinal axis. The V-shaped stent elements V.sub.1 and V.sub.2 are facing in opposite directions with respect to a circumferential axis A.sub.1.

(37) The same repeating series of stent elements (arranged identically with respect to the circumferential axis A.sub.1 and longitudinal axis L) proceeds along a second side 68 of the stent cells 62 and 64, but is offset such that the sequence begins with stent element v.sub.3 which is directly adjacent v.sub.1 of the series along the first side 66. Thus, beginning from the top of FIG. 7 along second side 68, the series of stent elements is v.sub.3, v.sub.4, V.sub.2, v.sub.1, v.sub.2, V.sub.1, v.sub.3, etc. Stated differently, the circumferential pattern may be considered as an M-shape, followed by a W-shape sharing a common leg with the M-shape, which is then repeated (as well as with the common leg).

(38) The first side 66 may be connected to the second side 68 via connectors C.sub.3. For instance, stent element v.sub.1 of the first side 66 may be connected to stent element v.sub.3 of the second side 68 at each instance along the circumferential axis A.sub.1 in which stent elements v.sub.1 and v.sub.3 are adjacent one another. The connectors C.sub.3 are attached to the stent elements v.sub.1 and v.sub.3 at about a peak portion thereof to align with the first leg portion thereof that is parallel to the longitudinal axis L. In stent 100, the connectors C.sub.3 have a width equal to the width of the first leg portions of v.sub.1 and v.sub.3. The side of stent elements adjacent to the second side 68 (toward the middle of the stent 100) are connected to the second side 68 in the same manner (that is, stent elements v.sub.1 and v.sub.3 are connected by connectors C.sub.3 at locations where the peak portion of v.sub.1 is adjacent the peak portion of v.sub.3). This pattern may continue along the length of the stent 100.

(39) It is noted that stent elements v.sub.2 and v.sub.4 are not connected to one another by any connector when the peak portions thereof are adjacent one another. In other embodiments, these peak portions are connected by a connector. In yet other embodiments, instead of stent 100 including only connectors C.sub.3, other connector types could be utilized. In still other embodiments, the connectors could connect V.sub.1 and V.sub.2 instead of, or in addition to connecting v.sub.1 and v.sub.3 and/or v.sub.2 and v.sub.4. For example, in one embodiment, a straight connector could connect V.sub.1 and V.sub.2 at locations where the peak portions thereof are facing away from each other (i.e., across stent cell 62). In one embodiment, the peaks connected by one or more of the connectors C.sub.3 could be touching, such that the effective length of one or more of the connectors C.sub.3 is zero.

(40) FIG. 8 shows stent 100 after the pattern has been cut into a tube. In one embodiment, the tube forming the stent 100 is a metal tube that is laser machined to form the repeating series of stent elements. In one embodiment, the stent has a diameter of about 6 millimeters and a thickness of about 0.0085 inch after electro-polishing. In an embodiment in which the stent 100 is covered by one or more graft layers, the stent 100 can be expanded to a larger diameter for covering with the graft layer(s), can be covered with the graft layer(s) at the cut diameter, or can be crimped to a smaller diameter for covering with the graft layer(s), following post processing steps such as, for example, electro-polishing.

(41) In the embodiment of FIGS. 7-9, the width of selected portions of the stent elements v.sub.1-v.sub.4 is tapered to a narrowed width for stent elements V.sub.1-V.sub.2 to promote uniform expansion of the stent. Such uniform expansion is particularly preferred for stents covered by graft material to avoid tearing or deformation of the graft material upon deployment. In other embodiments, the thickness of selected stent elements is reduced instead of, or in conjunction with, the tapered and narrowed of the widths thereof. In FIG. 9, widths w.sub.6-w.sub.9 are shown at different locations on the stent cells. Width w.sub.6 is at the beginning of second leg portion of stent element v.sub.2, width w.sub.7 is along the length of first leg portion of stent elements v.sub.1 and v.sub.2, width w.sub.8 is at a section of stent element V.sub.1, and width w.sub.9 is at a section of connector C.sub.3. In the embodiment shown, the widths of w.sub.6, w.sub.7, and w.sub.9 are the same, and the width of w.sub.8 is less than the widths of w.sub.6, w.sub.7, and w.sub.9. It is noted that the first leg portions and peak portions of stent elements v.sub.1-v.sub.4 have the same width along the length thereof (i.e., w.sub.6, w.sub.7), but second leg portions of each of stent elements v.sub.1-v.sub.4 taper from width w.sub.6 to width w.sub.8 along the length thereof. In one embodiment, which could be used in a vessel diameter of about 5 mm to about 15 mm, the widths of w.sub.6, w.sub.7 and w.sub.9 are in the range from about 0.0070 inch to about 0.0120 inch, for example about 0.0095 inch, and the width at w.sub.8 is in the range from about 0.0040 inch to about 0.0090 inch, for example about 0.0065 inch. For smaller or larger vessels, dimensions can be accordingly smaller or larger.

(42) In FIG. 9, the peak portions of the stent elements v.sub.1-v.sub.4 are shown longitudinally spaced a distance D.sub.3 from the peak portions of V.sub.1 and V.sub.2, which in one embodiment at a diameter of about 6 millimeters is in the range from about 0.005 inch to about 0.035 inch, for example about 0.018 inch. In other embodiments, the peak portions are circumferentially aligned. Also in FIG. 9, the peak portions of the stent elements v.sub.2 and v.sub.4 are shown longitudinally spaced, respectively, a distance D.sub.4 from the peak portions of the stent elements v.sub.3 and v.sub.1, which in one embodiment at a diameter of about 6 mm is in the range from about 0.005 inch to about 0.035 inch, for example about 0.012 inch. The distance D.sub.4 provides increased spacing for the unconnected peaks to allow additional room for expansion to better ensure that the unconnected peaks do not come into contact during delivery and/or deployment.

(43) While the invention has been described in terms of particular variations and illustrative figures, those of ordinary skill in the art will recognize that the invention is not limited to the variations or figures described. In addition, where methods and steps described above indicate certain events occurring in certain order, those of ordinary skill in the art will recognize that the ordering of certain steps may be modified and that such modifications are in accordance with the variations of the invention. Additionally, certain of the steps may be performed concurrently in a parallel process when possible, as well as performed sequentially as described above. Therefore, to the extent there are variations of the invention, which are within the spirit of the disclosure or equivalent to the inventions found in the claims, it is the intent to cover those variations as well.