MXPA98003504A - System of supply of endoprotesis of perfusion pas - Google Patents

Abstract

A method and system for delivery of stents is described. The system generally includes an elongated delivery liner and a perfusion catheter disposed within a lumen of the liner having an expandable member at its distal end. The liner includes perfusion gates to maintain blood flow to perfusion gates in the catheter during delivery of the stent. A manipulation device is provided at the proximal end of the delivery system to effect relative axial movement between the liner and the catheter to expose the stent mounted on the expandable member in the catheter within a body lumen such as a coronary artery and allow placement of the endoprosthesis by the expansib member

Description

SYSTEM FOR SUPPLYING ENDOPROTESIS OF PASSIVE PERFUSION BACKGROUND OF THE INVENTION This invention is generally related to devices for the treatment of heart disease and more particularly to endoarterial prostheses, which are commonly referred to as endoprostheses. Various intervention treatment modalities are currently used for heart diseases, including laser and balloon angioplasty, atherectomy, and bypass surgery. In typical balloon angioplasty procedures, a guiding catheter having a preformed distant tip is percutaneously included through the femoral artery into a patient's cardiovascular system in a conventional Seldinger technique and advanced into the cardiovascular system until the distant tip The guide catheter sits in the ostium of a desired coronary artery. A guide wire is placed inside an inner lumen of a dilatation catheter and then the catheter is advanced over the guide wire, through the guide catheter to the distal end of the guide catheter. The guidewire is first advanced out of the distal end of the guide catheter, into the coronary vasculature of the patient until the distal end of the guidewire crosses a lesion to dilate, then the dilatation catheter having an inflatable balloon in its distal portion is advances to the coronary anatomy on the previously introduced guidewire, until the balloon of the dilatation catheter is properly placed through the lesion. Once in position through the lesion, the balloon that is made of relatively inelastic materials is inflated to a predetermined size with radiopaque liquid at relatively high pressure (for example greater than 4,052 bars (4 atmospheres)) to compress the plate Atherosclerosis of the lesion against the inside of the artery wall and to otherwise expand the inner lumen of the artery. The balloon then deflates, so that blood flow can be resumed through the dilated artery and the dilatation catheter can be removed from there. Further details of dilatation catheters, guidewires and associated devices for angioplasty procedures can be found in U.S. Pat. Do not. 4,323,071 (Simpson-Robert); U.S. Patent No. 4,439,185 (Lindquist); U.S. Patent No. 4,516,972 (Samson); U.S. Patent No. 4,538,622 (Samson et al.); U.S. Patent No. 4,554,929 (Samson et al.); U.S. Patent No. 4,616,652 (Simpson); U.S. Patent No. 4,638,805 (Powell); and US patent. No. 4,748,982 (Horzewski et al.). One problem that can occur during balloon angioplasty procedures is the formation of internal fins that can collapse and / or occlude the artery when the balloon deflates at the end of the angioplasty procedure. In the case of a partial or total occlusion of a coronary artery by crushing the lining of a dissected artery after the balloon is deflated, the patient is exposed to a '5 an extremely dangerous situation that requires immediate medical attention, particularly in the coronary arteries. Another characteristic problem of angioplasty procedures of - ^ - balloon is the large number of patients who undergo restenosis in the treated artery. In the case of restenosis, A previously treated artery may again undergo balloon angioplasty or even a less conservative treatment such as bypass surgery. A significant focus of recent development work in the treatment of heart disease has been directed to devices called endoprostheses. Stent grafts are generally cylindrically shaped intravascular devices that are placed inside a damaged artery to keep it open. An endoprosthesis can be used to prevent restenosis and to maintain the opening of the vessel blood immediately after other intravascular treatments. In some circumstances, stents can also be used as the primary treatment device when they expand to dilate a stenosis and then leave them in place.

But the rapid and efficient delivery of a stent to the desired site within the vasculature has been found to be difficult, particularly in those situations in which an inner fin has occluded an artery. Attempts to advance a stent in regions of coronary arteries occluded by lining of dissected arteries have not been very successful. Two basic methods and systems have been developed to deliver endoprostheses to desired sites within body lumens. One method and system involves compressing or otherwise reducing the diameter of an expandable stent, placing the compressed stent within a lumen that is provided at the distal end of a tubular catheter, advancing the catheter through the patient's vasculature until the distal end of the catheter is immediately adjacent to the desired vascular location and then pushing the stent away from the distal end of the catheter to the desired site. Once out of the catheter, the compressed stent expands or is expanded to thereby keep the artery or other body lumen open in it. which one is placed Another method and system involves placing a compressed or otherwise small-sized endoprosthesis relative to an expandable member, such as a balloon, at the distal end of a catheter, advancing the catheter through a patient's vascular system, until the stent is at the desired site within the blood vessel and then expanding the member in the catheter to expand the stent within the blood vessel. The deployed expandable member then contracts or deflates and the catheter is removed, leaving the expanded stent within the blood vessel keeping its passage open. The following references illustrate various types of stents and endoprosthesis delivery systems. The list is intended exemplary, not exhaustive in the matter. Patent of the U.S.A. No. 3,868,956 U.S. Patent. No. 4,503,569 Patent of the U.S.A. No. 4,512,338 Patent of the US. No. 4,553,545 Patent of the U.S.A. No. 4,560,374 Patent of the U.S.A. No. 4,655,771 Patent of the U.S.A. No. 4,665,918 Patent of the U.S.A. No. 4,733,665 Patent of the U.S.A. No. 4,760,849 Patent of the U.S.A. No. 4,762,128 Patent of the U.S.A. No. 4,768,507 Patent of the U.S.A. No. 4,795,458 Patent of the U.S.A. No. 4,800,882 Patent of the U.S.A. No. 4,830,003 Patent of the U.S.A. No. 4,856,516 Patent of the U.S.A. No. 4,878,906 Patent of the U.S.A. No. 4,886,062 Patent of the U.S.A. No. 4,907,336 Patent of the U.S.A. No. 4,913,141 U.S. Patent. No. 4,923,464 U.S. Patent. No. 4,950,227 Patent of the U.S.A. No. 5,458,615 What has been required and to date is not available is a stent delivery system that can be used quickly and easily in a wide variety of situations and particularly in emergency situations, where a dissected arterial lining has been flattened and has occluded the flow of blood to a vital organ. The present invention satisfies this need. In addition, because the expandable member such as a balloon is inflated, the blood flow in the artery or vessel to be treated is occluded. The balloon can only be inflated for a limited amount of time, typically in the order of 15 to 60 seconds. A longer inflation time would be convenient because it would allow more time for the surgeon to deploy the stent, allow for maximum adaptation of stent-to-vessel and allow good support in the artery of the stent. On the other hand, risks of prolonged balloon inflation times include iscc conditions or angina in the tissue distant from the catheter.

The importance of continuous blood flow during percutaneous transluminal coronary angioplasty or during procedures performed in the peripheral vasculature is well recognized. Undoubtedly, an infusion-type dilatation catheter for angioplasty has been introduced to the market by Advanced Cardiovascular Systems, Inc. This catheter, which may take the form of an over-the-wire catheter, a fixed wire or a rapid exchange type, has one or more perfusion gates proximate to and one or more perfusion gates distant from the dilatation balloon. . The perfusion gates are in fluid communication with an inner guide wire lumen extending to the distal end of the catheter. When the balloon is inflated to dilate a stenosis, oxygenated blood in the artery or aorta or both is forced through the nearby perfusion gates, through the lumen inside the catheter, and out of the distant perfusion gates. The rapid exchange version of the perfusion-type dilatation catheter has an inner lumen or short guide wire receiving sleeve that extends through a distal portion of the catheter. The catheter structure allows for rapid exchange of the catheter unnecessarily by an exchange wire and without adding a guidewire extension to the proximal end of the guidewire. Details of this rapid exchange perfusion catheter are described, for example, in U.S. Pat. No. 5,040,548 (Yock).

Also of interest is the US patent. No. 5,368,566 (Crocker), which describes a temporary stent and delivery stent having a reinforced perfusion lumen. The temporary endograft in Crocker's reference is used only to maintain the opening of a body lumen while allowing fluid perfusion through the lumen. The patent of the U.S.A. No. 5,368,566 does not address the delivery of stent after angioplasty procedures. The patent of the U.S.A. No. 5,222,971 (Willard et al.) Discloses a temporary stent to support a region of a vessel comprising a stent portion and an actuator portion. The stent portion has an elongate perfusion vessel support portion, wherein the endoprosthesis provides a radially as well as axial or longitudinal path for fluid flow. However, there is still a need for a stent delivery system that includes a mechanism for blood perfusion during delivery of the stent to the deployment site. SUMMARY OF THE INVENTION The present invention is directed to an improved stent delivery system, which can quickly and easily place a stent in an occluded region of a blood vessel. In a preferred embodiment, the endoprosthesis delivery system of the present invention includes a means for perfusing fluid. A preferred embodiment of the present invention is directed to a catheter structure for maintaining the opening of a body lumen for a period of time sufficient to allow delivery of an expandable stent within the body lumen, wherein the structure comprises an elongated delivery liner. having proximal and distant ends, a lining lumen extending there, a first gate at the far end, which is in fluid communication with the lumen of the liner, and at least one liner perfusion gate at the proximal end in communication fluid with the lining lumen. Modalities of the present invention also include an elongate catheter slidably positioned within the lining lumen of the liner, an adjacent expandable member proximal to the distal end of the catheter receiving on its exterior the expandable stent, an inner lumen extending the length of the catheter elongated to receive a guide member and extending over the entire length of the inner lumen, and at least one catheter perfusion port in the catheter, in fluid communication with the inner lumen. Also included are means for adjusting the relative axial positions of the catheter and liner to expose the expandable member so that its expansion opens the expandable stent.

Preferably, both the delivery liner and the catheter have grooves in their walls extending distally from their proximal gates, to facilitate rapid removal of these guiding devices when removing the delivery system from the patient's vascular system after delivery of an endoprosthesis. The distal end of the supply liner may also have grooves in its walls, which extend a short distance proximal to its distal end, to facilitate relative axial position adjustment of the delivery liner and catheter. In a typical situation, the guide wire is used to deliver a dilatation catheter through the vascular system to a stenotic region, which is left inside the patient after the dilatation catheter has been removed. To maintain access to the stenotic region, the distal end of the guidewire should be placed in such a manner that it crosses the stenotic region where the stent is to be placed. The proximal end of the guidewire, which extends outside the patient, is first inserted through an elastic cone by screwing the guidewire to the smallest opening in the cone and out of the larger of the two cone openings. Then, the guidewire is inserted through the gate at the distal end of the intravascular catheter, which has a stent mounted on the expandable member. The intravascular catheter is disposed within the delivery liner with the distal end of the catheter extending out of the gate at the distal end of the delivery liner to facilitate insertion of the proximal end of the guidewire. The relative axial position of the delivery liner and intravascular catheter is adjusted such that the expandable member at the distal end of the intravascular catheter with the expandable stent mounted is retracted into the inner lumen of the delivery liner. The distal end of the supply liner is then fitted into the large opening of the elastic cone. Fitting the supply liner into the elastic cone aids in the advancement of the endoprosthesis delivery system through the vascular system by providing the system with a suitable profile to perform turns through the tortuous vessels. The delivery liner and the catheter are then advanced through the vascular system, preferably over a guidewire extending from outside the patient to the desired coronary artery, until the stent mounted on the expandable member of the intravascular catheter is placed inside. of the stenotic region of the target vessel. The relative axial positions of the delivery liner and the intravascular catheter having the stent are adjusted such that the liner is removed proximally (in a direction away from the patient) to expose the distal end of the vascular catheter and the expandable stent. . As the relative axial positions are adjusted, the cone detaches from the liner and collapses on the distal end of the catheter. Once the stent is completely out of the delivery liner, the expandable member in the intravascular catheter can expand to in turn expand the stent against the walls of the blood vessel. After expanding the stent, the expandable member in the vascular catheter contracts in such a manner that the catheter can be removed from the patient, leaving the stent-graft expanded in its desired position in the target vessel. During delivery of the endoprosthesis to the deployment site, perfusion gates within the liner and the catheter provide continuous blood flow through the lining lumen and inner lumen of the catheter. From the inner lumen, the effluent blood passes through the perfusion gates at the distal end of the catheter to tissue distant from the catheter. Even as the liner is removed, the perfusion gates in the liner allow for continuous flow of blood to the perfusion gates in the catheter shaft. Beneficially, the perfusion gates of the present invention in the liner and catheter prevent or minimize the occurrence of ischemic conditions in the patient. Furthermore, the infusion of blood distant from the inflated balloon allows for long-term dilatations.

The catheter and delivery liner can be removed as a whole or the liner can be removed first, followed by the catheter. The liner and the catheter can be detached from the guidewire, with the guidewire sliding through the slots extending distally from the proximal gates of the catheter. The exposed section of the guide wire is held, for example manually held in place, such that the liner and the intravascular catheter can be detached from the proximal end of the guidewire. In an exemplary embodiment of the invention, an over-the-wire catheter system is employed to deliver a stent to a site in the vascular system. The over-the-wire catheter includes a proximal arrow and a distant arrow that retracts in the proximal direction by operation of a liner retraction switch in a supply handle. An elongate liner is at the distal end of the distal arrow and covers and protects the stent and balloon member on the catheter shaft during intravascular delivery. When the liner retraction switch is By moving in the proximal direction, the liner is caused to move proximally, thereby exposing the stent, such that it can be deployed. The delivery system of the invention can effectively deliver a stent to a desired site Within a patient's glass, it can allow the stent to be held within the desired location and be removed quickly and easily. These and other advantages of the present invention will become more apparent from the following detailed description, when taken in conjunction with the accompanying exemplary drawings. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a cross sectional view > partial longitudinal of a stent delivery system incorporating features of the invention, including perfusion gates in the catheter and liner. Figure 2 is a top view of the supply liner with perfusion ports and elastic cone of the endoprosthesis delivery system illustrated in Figure 1. Figure 3 is a cross-sectional view that is taken on lines 3-3 shown in Figure 1. Figure 4 is a cross-sectional view taken on lines 4-4 shown in Figure 1. Figure 5 illustrates a stent mounted on the outer surface of a balloon of an intravascular catheter in exemplary mode such as that illustrated in Figure 1. Figure 6 illustrates the advancement of the stent delivery system as illustrated in Figure 5, in an artery that has been damaged by a intravascular procedure such as an angioplasty procedure, and the location of the elastic cone before the relative axial position adjustment of the intravascular catheter and supply liner. Figure 7 illustrates the balloon inflation in the intravascular catheter shown in Figure 1, which expands the endoprosthesis mounted on its exterior, and the location of the elastic cone after the relative axial position adjustment of the intravascular catheter and delivery liner. Figure 8 shows the expanded stent disposed within a damaged arterial section that maintains its opening. Figure 9 is a partial cross-sectional view of the manipulator shown in Figure 1. Figure 10 is a perspective view of an alternating manipulator mounted at the proximal end of the delivery system illustrated in Figure 1. Figure 11 is a plan view of the manipulator shown in Figure 10. Figure 12 is an elevation view, partially in section of the manipulator shown in Figure 10. Figure 13 is a longitudinal view of a stent delivery system incorporating features of a Over-the-wire catheter system. Figure 14 is a partial plan view of the delivery liner of the stent delivery system shown in Figure 3 including optional perfusion gates in the liner. Figure 15 is a longitudinal view of a stent delivery system in which the supply liner is illustrated in its retracted position. Figure 16 is a partial plan view of the stent delivery system of Figure 15, which shows the supply liner after it has been removed from the delivery stent. Figure 17 is a cross-sectional view of the distal portion of the liner for the stent delivery system of Figure 15, with perfusion gates illustrating the liner as it is partially removed from the stent. Figure 18 is a cross-sectional view taken on line 18-18 of Figure 17, showing the distal end of the catheter and the elastic cone. Figure 19 is a cross-sectional view taken on line 19-19 of Figure 17, showing the liner in relation to the catheter system. DETAILED DESCRIPTION OF THE PREFERRED MODALITIES Figures 1 to 4 illustrate preferred embodiments of a stent delivery system having characteristics of the invention. In general, the delivery system includes a supply liner 10 having a liner lumen 11 and a catheter 12 disposed within the liner lumen 11. As illustrated in Figure 1, the supply liner 10 preferably includes gates of perfusion liner 1 and distant infusion perfusion gates 2. The perfusion gates 1, 2 are in fluid communication with the lining lumen 11. The location of the gates 1, 2 on the liner 10, can of course be varied depending of the application. Also, the size, shape and orientation of the perfusion gates 1, 2 can be changed as required. For example, perfusion gates in alternate modalities may be round trades, vertical grooves, horizontal grooves and the like. The exemplary embodiment of intravascular catheter 12 shown in Figure 1 has an elongate catheter body 13 and a balloon 14 in the distal portion of the catheter body 13. A manipulation device 15 is provided at the distal end of the delivery system that it is employed to effect relative longitudinal or axial movement between the delivery liner 10 and the intravascular catheter 12. An expandable stent 16, which is to be delivered within a patient's body lumen, is mounted on the outside of the balloon 14. During advancement of the endoprosthesis delivery system through the vascular system to the region of an occlusion, the liner 10 engages within an elastic cone 58. Figure 1 shows the location of the elastic cone 58 after the relative axial positions of the liner 10. and the catheter 12 are adjusted to expose the expandable stent 16. The supply liner 10 has a remote gate 17 at its distal end, which e is in fluid communication with the lining lumen 11 and a proximal gate 18 disposed proximate the remote gate. The distal portion of the supply liner 10 tapers downward in a spherical type shape, such that the cross-sectional area is somewhat smaller in the distant region than the sectional area.

Cross section of the rest of the supply liner. A slit 19 extends from the proximal gate 18 to a site just proximal to the remote gate 17. In one embodiment, a plurality of slits 59 in the wall of the supply liner 10 extends a short distance from the remote gate. 17. As contemplated, the slits 59 will facilitate the relative axial position adjustment of the delivery liner 10 and the intravascular catheter 12. The intravascular catheter 12 has a remote gate 20 and a proximal gate 21, which are in fluid communication with a first inner lumen 22, which extends within the distal portion of the catheter 12 and is adapted to slidably receive a guidewire. A slit 23 extends from the proximal catheter gate 21 to a site 24, close to the proximal end of balloon 14.

The proximal end of the first guide wire receiving lumen 22 is provided by a ramp 25 to guide the proximal end of the guide wire 26 out of the proximal gate 21 of the intravascular catheter 12, when the catheter is mounted on the guide wire as will be discussed then. A second much longer inner lumen 27 is provided within the catheter body 13 to direct inflation fluid from the proximal end of the catheter body to the inside of the balloon At least one perfusion catheter for catheter optional 3 is located in a proximal portion of the catheter body 15 and is in fluid communication with the first inner lumen 22. In this manner, the blood circulates through the liner perfusion gates 1, 2, then through the lumen of lining 11 and finally through the perfusion gate of catheter 3 within the first interior lumen 22. Blood passes through the distal catheter gate 20, or through the optional perfusion gates at the distal end of the catheter body 13 to supply tissue distant from the balloon 14. Near the proximal gate 21 in the catheter body 13 is a reinforcing member 28, which is disposed in the third inner lumen placed within the catheter body 13. As shown in the drawings, the third inner lumen 29 and the first interior lumen 22 may be the same lumen with a plug 30 separating the two lumens. The ramp 25 is at the distal end of the cap 30. As illustrated in Figures 1 and 9, the manipulator 15 at the proximal end of the delivery system has a housing 31 with an inner chamber 32, a cap 33 rotatably mounted on the the remote end of the housing 31, an elongated thrust member 34 having male threads on its outside and at least partially disposed in the inner chamber 32, and a Luer latch 35 which is fixed within the end near the housing 31. The proximal end 36 of the liner 10 is fastened to the distal end 37 of the elongated momentum member 34, which extends away from the distal end of the housing 31. As illustrated in more detail in Figure 9, the end next 38 of catheter body 13 passes through of a passage 39 in the elongate pulse member 34 and is secured within the Luer lock 35 by convenient means such as an adhesive. The cap 33, which is rotatably mounted on the distal end of the housing 31, is provided with an internal threaded collar 40 adapted for threaded coupling the threaded outer of the elongated impulse member 34. The rotation of the cap 33 axially moves the impulse member 34 to thereby effect relative axial movement between the delivery liner 10 and the intravascular catheter 12. As can be seen in the Figures 1 and 6, the lining lumen 11 is axially separated from the catheter 12, in the second inner catheter lumen 27, in a non-confining to substantially abutting manner. In this way, when the delivery liner 10 superimposes the intravascular catheter 12, there is little or no contact present at the interface between the lining lumen 27 near the distal end of the intravascular catheter 12. In a typical situation, the delivery system The stent of the present invention is used after an intravascular procedure has damaged the lining of a patient in such a proportion that the lining requires support to avoid crushing the arterial passage, thus compromising the sufficiency of blood flow through the affected vessel. In these situations, there is usually a guide wire 26 (or other guide member) in place that extends through the damaged section of the artery, as illustrated in Figure 6. The proximal end of guide wire 26 extending out of the patient throughout the procedure, is inserted through the elastic cone 58 by screwing the guide wire 26 into the small opening 61 and outside the large opening 60 of cone 58. The guide wire 26 is then inserted through the remote gate 20 at the distal end of the catheter 12 and advanced proximally through the first inner lumen 22, until the proximal end of the guidewire impacts the ramp 25 and thus direct through the next hatch 21.

The catheter 12 is preferably placed within the lining lumen 11 of the delivery liner 10, such that at least a significant portion of the proximal gate 18 in the delivery liner is in alignment with the proximal gate 21 of the intravascular catheter. In this manner, the proximal advancement of the guidewire 26 through the first inner lumen 22 of the catheter will also direct the proximal end of the guidewire out of the proximal gate 18 into the supply liner 10. The supply liner 10 is then fitted inside. of the elastic cone 58 by inserting the distal end of the supply liner 10 to the proximal end and large opening 60 of the cone 58. The proximal end of the guidewire 26 can then be held manually to maintain the position of the guide wire within the vasculature of the patient, while the endoprosthesis delivery system is advanced over the guide wire and through the vascular system. One function of the elastic cone 58 is to facilitate the advancement of the endoprosthesis delivery system. By engaging the distal end of the supply liner 10 within the cone 58 as illustrated in Figure 6, the stent delivery system has a profile suitable for successfully maneuvering through the marked turns and angles of the patient's vasculature. The advancement of the stent delivery system continues until the distal end of the catheter and the distal end of the liner extend adjacent to or through the damaged arterial site. Next, the manipulator 15 at the end next to the delivery system is actuated by rotating the cap 33 at the proximal end of the housing 31, to move the supply liner 10 proximal with respect to the catheter 12, and to thereby expose the stent 16 mounted on the balloon 14. The elastic cone 88 detaches the supply liner 10 and flattens in engagement with respect to the distal portion of the catheter 12 as illustrated in Figure 1. 10 When the balloon and stent mounted thereon are properly positioned Within the damaged artery, the inflation fluid is directed under substantial pressure through the manipulator Luer lock 35 and the catheter inflation lumen 27 in the catheter body 13 into the interior of the balloon 14, expanding the balloon and simultaneously expanding the stent 16 against the vessel wall at the target site as illustrated in Figure 7. The delivery system (both delivery liner 10 and catheter 12) can then be removed from the patient along with the wire guide 26, leaving the stent expanded within the damaged arterial section to maintain its opening as illustrated in Figure 8. The housing 31 of the manipulator 15 can be held in the palm of a doctor's hand, the thumb and forefinger being used to rotate the lid 33 and in this way cause the necessary relative movement between the delivery liner 10 and the intravascular catheter 13 to expose the endoprosthesis 16 mounted on the balloon 14. The doctor can operate an inflation device, such as that described in US Pat. No. 4,439,185, with his free hand, to inject inflating fluid 5 through the Luer 35 inside the balloon 14, to inflate the balloon and thereby expand the stent 16 while maintaining the system M. supply on site with the other hand. By deflating the balloon 16, the manipulator 15 can be operated again by rotating the lid 33 with the fingers of the hand holding the manipulator , to cause relative rotation between the intravascular catheter 12 and the supply liner 10, to pull the intravascular catheter 12 back to the distal end of the supply liner 10 (or push the distal end of the liner on the distal end of the intravascular catheter 12, depending on the perspective). The entire structure, including guide wire 26 can then be removed from the patient. The alternate manipulator 50 illustrated in Figures 10 to 12 generally includes a housing 51 with a camera and a sliding element 53 with a dependent portion 54, which extend through a slot 55 in the wall of the housing and which is fastened to the proximal end of the supply liner 10, which extends through an aperture provided at the far end of the accommodation.

The catheter 12 extends out of the proximal end of the supply liner 10, out of an opening in the proximal end of the housing 51 and into the Luer latch 56 attached to the proximal end of the housing. The proximal end of the catheter 12 is held within the Luer lock 56 to be in fluid communication with the second inner inflation lumen 27 of the catheter, so that inflation fluid can be injected through the Luer lock into the balloon 14 in the catheter to expand the balloon and the stent 16 mounted there. As is evident from Figure 10, the movement member 53 on the exterior of the housing 51 will effect relative axial movement between the delivery liner 10 and the catheter 12, this relative axial movement being required to expose the expandable stent 16 mounted on the balloon 14. Slot 55 has narrowed portions near both of its ends. These narrowed portions have widths that are only slightly smaller than the portion. dependent 54, such that the position of the slidable member 53 can be latched or secured. The underside of the housing 51 can be provided with a corrugated surface 57, which is adapted to receive the fingers of an operator for ease of attachment. In another exemplary embodiment of the invention, as illustrated in Figures 13 to 19, an over-the-wire catheter system is employed to transport the delivery liner and stent into the vasculature of a patient to the damaged area.

A guide wire 26 is used to cross the damaged area and locate the position of interest in the patient such that the intravascular catheter 12 can reach the area. As is typical in over-the-wire catheter systems, the intravascular catheter 12 has an outer member 77 and an inner member 78 that are coaxially aligned. The inner member 78 has an inner lumen 79 which carries a guidewire 26. The guidewire can move freely inside the inner lumen 79 in an axial direction. Following the invention, as illustrated in Figures 13 to 19, the supply liner 10 is located at the distal end of a distant retractable liner 74. The catheter 12 is slidably disposed within the supply liner 10 in the interior lumen of the liner 11. The gate 17 in the Distant end of the supply liner 10 provides an opening through which the catheter 12 can extend 12. The supply liner 12 has a flared portion or an expanded portion located at the distal end of the distant retractable liner 74. It is contemplated that the liner 10 can be formed from the same arrow as the distant retractable liner 74, or it can be a separate member (not shown) connected to the distal end of the distant retractable liner 74. The elongated or flared diameter portion of the supply liner 10 should be large enough to house the underlying balloon 14 and the expandable stent 16. It is also contemplated that the supply liner 10 may not have a porc flared ion as illustrated, in order to reduce the profile of the supply liner 10. A notch 80 at the distal end of the supply liner 10 is incorporated to provide a softer and more flexible distant end to the supply liner 10. When the intravascular catheter 12 moves through the vasculature of the patient, a softer remote end for the supply liner 10 is convenient, and the notch 18 provides flexibility and the required smoothness. More than one notch is contemplated to further increase flexibility and smoothness at the distal end of the supply liner 10. If a stiffer, less flexible end is desired, the supply liner 10 may be provided without any notch. The distant retractable liner 74 is connected to a proximal retractable liner 75 comprising a member with a slightly larger diameter and greater stiffness, than the distant retractable liner 74. In this manner, the distal end of the liner will have more flexibility than the proximal end. . It is also contemplated that the invention incorporates a retractable liner characterized by only one diameter over its length, to provide uniform stiffness.

An elastic cone 58 is connected to the intravascular catheter 12 near its distal tip. The elastic cone 58 has a large opening 60 that is sufficiently elastic to superpose the very distant end of the supply liner 10. The elastic cone also has a small opening 61 at its distal end that connects to the outer member 77 of the catheter on the -Wire by known methods such as thermal shrinkage or by an adhesive. The elastic cone 58 is # intended to provide coverage on the extreme Distant from the liner 10, as the liner moves through the tortuous vasculature and will prevent the liner 10 from being trapped in the vasculature. In addition, the intravascular catheter 12 includes optional catheter perfusion gates 5 at its end distant. The catheter perfusion gates 5 are in fluid communication with the inner lumen 79 of the inner member 78 of the over-the-wire catheter that carries the guidewire 26. A blood inflow flow optionally will be delivered to the remote perfusion gates 5. to through the inner lumen 79 from a blood supply source 6 as is known in the art of perfusion catheters. In addition, the supply liner 10 in the preferred embodiment includes liner perfusion gates 4, such as horizontal grooves illustrated in Figures 14 and 16. Of course, the size, shape, location and orientation of the liner perfusion dampers 4 can be adjusted to allow particular applications. The perfusion gates 4 allow blood flow through the supply liner 10. The liner perfusion gates are useful in an alternate mode of the catheter having proximal perfusion gates (not shown). Specifically, as the liner 10 retracts, the liner perfusion gates 4 * ensure continuous blood flow in the event that proximal catheter perfusion ports are covered or blocked by the supply liner 10 as it retracts. A blood supply 6 known in the art directs blood through the inner lumen 79 of the inner member 78 of the over-the-wire catheter. The blood flows to through the inner lumen 69 and out of the perfusion gates to the catheter 5 to the distal tissue of the catheter 12. As described above, the delivery liner 10 provides a protective cover for the stent 16, while the stent is transported to the endoprosthesis 16. through the vasculature of the patient. Once the damaged area has been crossed, the stent is then ready to deploy. In order to deploy the stent, a manipulator handle 70 is used to retract the supply liner 10. The The proximal end (not shown) of the proximal retractable liner 75 is connected to a connector 72. A liner retraction switch 71 can be operated by the doctor's thumb by moving the switch in the proximal direction. The liner retraction switch 71 is connected to the connector 72 which is slidably mounted in an elongated slot 73. As the liner retraction switch 71 moves in the proximal direction, the next retractable liner 75 and the distant retractable liner 74 also becomes move in the next direction. Because the supply liner 10 is connected to the distant retractable liner 74, a distance sufficient to expose the expandable stent 16 and balloon 14 is also moved in the proximal direction. It is preferred to place a radiopaque marker 67 near the end. Distant of the delivery liner 10, such that the doctor can determine when the liner 10 has been removed a sufficient distance so as not to interfere with the deployment of the stent 16. Alternatively, the radio-opaque marker can be placed on the site. 68 (Figure 14) instead of at the site indicated by the radio-opaque marker 67. When the radio-opaque marker 68 is placed in the distant retractable liner 74, has a smaller profile than the radio-opaque marker 67, thus allowing the supply liner 10 to cross an occluded area more easily. In order to deploy the expandable endoprosthesis 16, the balloon 14 is inflated with an inflation fluid through an inflation gate 65. As illustrated in Figure 17, a supply of inflation fluid 7 known in the art directs fluid balloon inflation 14. After the expandable stent 16 is deployed, balloon 14 deflates and intravascular catheter 12 is removed from the patient's vasculature. In the preferred embodiment of the present invention, the dimensions of the intravascular catheter generally follow the dimensions of the intravascular catheters employed in angioplasty procedures in the same arterial location.

Typically, the length of a catheter for use in the coronary arteries is approximately 150 cm (59 inches), the outer diameter of the catheter shaft is approximately 0.89 mm (0.035 inches), the length of the balloon is typically approximately 2 cm ( 0.79 inch) and inflated diameter about 1 mm to about 8 mm (0.04 to 0.31 inch). The construction materials can be selected from those employed in conventional balloon angioplasty catheters, such as those described in the patents previously referred. The supply liner will generally be slightly shorter than the intravascular catheter, for example in approximately the length of the handling devices 15 or 50, with an inside diameter large enough to accommodate the intravascular catheter and allow the free longitudinal movement of the catheter inside the supply liner. The liner and catheter shaft can be made from conventional polyethylene tubing. While the present invention has been described herein in terms of supplying an expandable stent to a desired site within a blood vessel of a patient, the delivery system can be used to provide endografts on site within other body lumens such as the urethra or the fallopian tubes, so that the # Stents can be expanded to maintain the opening of these 10 body lumens. Various changes and improvements to the invention can also be made without departing from its scope.

Claims (12)

1. CLAIMS 1. A catheter structure for maintaining the opening of a body lumen for a period of time sufficient to allow delivery of an expandable stent in the body lumen, characterized in that it comprises: an elongated liner having proximal and distant ends, a lumen of lining that extends there, a first gate at the far end that is in communication # fluid with the lining lumen, and at least one gate 10 perfusion of lining in the lining in fluid communication with the lining lumen; an elongate catheter disposed within the lining lumen and having a proximal end and a distal end, wherein the catheter includes at least one catheter perfusion gate, the elongated catheter has a member 15 outside and an inner member, an expandable adjacent member proximate the distal end of the outer member receiving the expandable stent on its exterior, an inner lumen on the inner member receiving a guide member and extending the entire length of the inner lumen , the inner lumen 20 is also in fluid communication with the catheter perfusion port and means for adjusting the relative axial positions of the catheter and liner to expose the expandable member, such that its expansion deploys the expandable endoprosthesis and allows blood to circulate through of the first gate in the liner and the catheter perfusion port at least.
2. 2. A system for supplying an expandable endoprosthesis within a body lumen on a guide member, characterized in that it comprises: an elongate liner having proximal and distant ends, a lining lumen extending, a first gate at the distal end of the liner which is in fluid communication with the lining lumen and a gate of # perfusion in the lining, in fluid communication with the lumen of 10 lining; an elongate catheter slidably disposed in the lining lumen, an adjacent expandable member proximal to the distal end of the catheter receiving on its exterior the expandable stent, an inner lumen extending the length of the elongate catheter to receive the guiding member 15 and extending over the entire length of the inner lumen, and at least one catheter perfusion port in the catheter in fluid communication with the inner lumen; and means for adjusting the relative axial positions of the catheter and liner to expose the expandable member and stent 20 expandable.
3. 3. The stent delivery system according to claim 2, characterized in that the liner has a tapered portion at its distal end.
4. 4. A catheter structure for maintaining the opening of a body lumen for a period of time sufficient to allow delivery of an expandable stent within the body lumen, characterized in that it comprises: an elongate liner having a proximal end and a distal end, a portion flared near the distal end, a tapered portion proximate the flared portion, H a lining lumen extending there, a first gate at the far end and a second gate at the end Next, both gates are in fluid communication with the liner lumen, and at least one liner perfusion gate in the liner in fluid communication with the liner lumen; an elongate catheter slidably disposed within the liner lumen, an adjacent expandable member proximal to the end 15 is remote from the catheter receiving the expandable endoprosthesis on the outside, an inner lumen extending along the length of the elongated catheter to receive a guide member and extending over the entire length of the inner lumen, and at least one perfusion gate catheter in the catheter in 20 fluid communication with the inner lumen; an elastic cone having a proximal end and a distal end and having a small opening at the distal end and a large opening at the proximal end, the large opening receiving the distal end of the elongated liner; and a manipulative handle that has a The switch adapted to move axially in the handle, the switch is connected to the proximal end of the liner, such that as the switch moves closer, the liner moves proximally to expose the stent and the expandable member.
5. 5. The catheter according to claim 4, characterized in that the liner perfusion gate includes a plurality of vertical slots.
6. 6. The catheter according to claim 4, characterized in that the liner perfusion gate 10 includes a plurality of horizontal slots.
7. The catheter according to claim 4, characterized in that the catheter perfusion gate includes a plurality of slots.
8. The catheter according to claim 15 4, characterized in that the liner further comprises a liner perfusion gate in fluid communication with the liner lumen and located at the distal end of the liner.
9. 9. A method for delivering an expandable stent to a desired site within a body lumen of a The patient having a guide wire disposed with a proximal end extending away from the patient, the method is characterized in that it comprises the steps of: providing an elongated liner with a liner lumen and a perfusion liner gate in fluid communication with the patient. lumen of 25 liner, the liner has proximal and distal ends, and a first gate at the distal end of the liner; providing an elongate catheter disposed within the elongated liner, the catheter has an expandable member adjacent to the distal end of the catheter and has the expandable stent mounted on the outside, the catheter has the inner lumen adapted to slidably receive a guidewire, the guidewire extends over the entire length of the inner lumen, wherein the catheter further includes a catheter perfusion gate in fluid communication with the inner lumen; advancing the liner and catheter over the guidewire through the body lumen to the desired site; adjusting the relative axial position of the liner relative to the catheter to expose the expandable stent in the expandable member; deploying the expandable member to expand the endoprosthesis mounted at the desired site within the body lumen; contracting the expandable member in the catheter; and remove the catheter and lining of the body lumen.
10. The method according to claim 9, characterized in that the expandable member includes a balloon and wherein an inflation fluid is directed into the interior of the balloon to expand the balloon and thereby expand the endoprosthesis thereon.
11. 11. The method according to claim 9, characterized in that the method further comprises the step of perfusing a fluid through the liner perfusion gate. The method according to claim 9, characterized in that the step of providing an elongated liner includes a liner having a plurality of perfusion gates.