CA2091561C

CA2091561C - Check valve catheter

Info

Publication number: CA2091561C
Application number: CA 2091561
Authority: CA
Inventors: Thomas M. Young
Original assignee: Strato Infusaid Inc
Current assignee: Strato Infusaid Inc
Priority date: 1990-10-10
Filing date: 1991-09-13
Publication date: 1996-08-20
Anticipated expiration: 2011-09-13
Also published as: JPH07108320B2; AU8911691A; DE9190142U1; US5156600A; JPH05505966A; AU653973B2; ATE127027T1; GR3017489T3; CA2091561A1; WO1992006732A1; EP0552313A1; ES2076744T3; DK0552313T3; DE69112632T2; DE69112632D1; EP0552313B1

Abstract

A valved catheter having an elongated, flexible tubular element (12) extending along a central axis (A) and a flow portion of a valve assembly (10) which controls fluid flow in the tubular element. The element is adaptable for bidirectional flow of fluid between its proximal (14) and its distal (16) ends, with a bidirectional valve assembly (24) coupled to the interior of the tubular element. The bidirectional assembly generally defines a control plane (26) which intersects the central axis at an oblique angle.
Theassembly has an inflow portion (53) and an outflow portion (55) nominally disposed to lie in the control plane. The inflow portion includes an inflow vane (56) positioned between the intersection of the control plane with the central axis and the distal end and which is adapted to be deflected out of the control plane toward the distal end in response to the establishment of a rela-tively high fluid pressure at the proximal end and a relatively lower fluid pressure at the distal end. The outflow portion also in-cludes an outflow vane (58) positioned between the intersection of the central plane with the central axis and the proximal end and which is adapted to be deflected out of the control plane toward the proximal end in response to the establishment of a rela-tively low fluid pressure at the proximal end and a relatively higher fluid pressure at the distal end.

Description

2 0 ~ 1 5 6 1 PCI/US91/06486 .
~ . . ~ .

5 ~ CHECK VALVE CATHETER
Backqround Of The Invention The prese"l invention relates to a catheter intended for implantation within a living body for long term usage, and more particularly to an implantable single lumen cdtl,eter having a bidirelctional check valve for controlling fluid flow into and out of the 10` catheter.
Various medical proce-Jures require vascular access over a period of time. Such ~ruce~ures may include implantation of a pe~rmane~nt intravascular device for portable drug infusion devices, for hemoJialysis, or for cases where continuous blood work or access to the t Ic^ ~ '.e~n is required. These procedures ue often pe, fl,,.ned by using 15 either transcutaneous or totally implanted catheters and fluid access devices.
There are problems Associ~ted with long term cathete, i~lion of a blood vessel.
A first pr~i 'en, is infection at the skin puncture point, and a second ~rc~ 1~ " is clotting of blood within the cdtl,~ter lumen. The first problem may be solved by installing a suhultAneous fluid access assernbly in a patie~nt and which is coupled to the p&lier,ls 20 lo^ ~ ' ~&m by me~ans of an implanted cathe~ter. As for the second problem, in cases where the flow rate of the fluid carried by the catheter is very high or p e,l,aps if an anti-coAgu'~rlt is carried by the fluid in the catheter, then the catheter will remain open to fluid flow over the long term. However in situations with low fluid flow rates or only inter",itlel,l fluid flow, clots or plugs may forrh inside of the catheter lumen, thus 25 obstructing fluid flow. This limits the useful lifetime of the i",planted catheter, or requires consl~Ar,l flushing or hepari"iLalion.
It has also been ex~erienced that changes in blood pressure may cause a ~luctlJAting pressure at the tip of an implanted catheter. Such fluctuAtion can induce a backlh~w of blood up the cc.li,~ter. This blood is subject to clotting.
A known cGrrn "ercially available bidirectional check valve catheter features a slit valve. The tip of the catheter is closed and the side wall of the catheter near the tip is slit, to form the slit valve. The valve allows both -sF:.dtion of blood and infusion of fluids. The check valve precludes the diffusion of blood into the lumen when thecatheter is not in use. This catheter is known as the Groshong catheter (available from Catheter Tecl-nology Corporation, Salt Lake City, Utah).

~.

While various other valved catheters are also known, there is still a need for an lmproved lmplantable, bldirectional check valve catheter assembly wlth long useful life, which does not require special maintenance, and with low potential of formation of obstructions, such as emboli.
Summary of the Invention The present invention provides a valve catheter comprislng an elongated, flexible tubular element extending along a central axls and having a proximal end and a dlstal end and being adapted for flow of fluid between said ends, a valve assembly coupled to the interior of the tubular element, said assembly generally deflning a control plane which lntersects said central axls at an obllque angle, sald assembly havlng a flow portlon disposed to lie ln sald control plane whereby said assembly establishe~ a fluid seal across the interior of said tubular element at said control plane, said flow portion including a flexible vane having its periphery affixed at least in part to the lnterior of said tubular element and being positioned between said intersection of said control plane wlth sald central axis and said ends and adapted to be deflected out of said control plane ln response to the establishment of a relatively high fluld pressure at one of said ends and a relatively low fluid pressure at the other of said ends.
In a preferred embodlment, the element is adapted for bidirectional flow of fluid between its proximal and lts distal end, having a generally planar bidirectional valve assernbly coupled to the interlor of the tubular element. The assembly has an inflow portlon and an outflow portlon nomlnally (e.g., at rest) dlsposed to lie in the control plane. The lnflow portlon lncludes an lnflow vane posltioned between the lntersectlon of the control plane wlth the central axls and the dlstal end and whlch ls adapted to be deflected out of the control plane toward the dlstal end in response to the establishment of a relatlvely hlgh fluld pressure at the proxlmal end and a relatlvely lower fluld pressure at the distal end. The outflow portlon also includes an outflow vane posltioned between the lntersection of the central plane wlth the central axls and the proxlmal end and whlch ls adapted to be deflected out of the control plane toward the proxlmal end ln response to the establlshment of a relatlvely low fluld pressure at the proxlmal end and a relatlvely hlgher fluld pressure at the dlstal end.
Embodiments of the lnventlon may lnclude several varlations. The valve assembly may be other than generally planar, and the control plane may be a nomlnal control plane.
The valve assembly may include reslllent and deflectable portlons such - 2a -wog2/06732 2 ~ 9 1 S 6 1 PCI/US91/06486 . ~ , -3- .

that the inflow vane is ~lispl-~e~~le by flexing in a first 'i~ction generally along the central axis and the outflow vane is ~''sFl--e-~'e by flexing in a second direction opposite to the first direction generally along the central axis.
In one form, for an elliptical or circular cross-section c~ll,eter, the ~ssembly5 includes a flexible elliptical disk-shaped ele "ent which nominally lies in the control plane. At least a part of the periphery of the elliptical disk-shaped element is amxed to the interior of the tubular element. The elliptical disk-shaped element defines two disk axes normal to the central axis. The two disk axes include a major axis and a minor axis which is normal to the major axis. The periphery of the elliptical disk-sl.~ed 10 ~'emenl which is located about (such as at and r1~ nt to) the minor axis is affixed to the interior of the tubular element along a first portion and a second portion of the periphery. A third portion of the periphery defines the inflow vane and is located at and adjacent to the major axis, displ- ,,e-'le in a first direction generally along the central axis. A fourth portion of the periphery defines the outflow vane and is located at and 16 adjacent to the major axis, ~ispl-^eAI~le in a second direction opposite to the first direction ge,nerally along the central axis. Either vane may be defined by an arcuate sey",e, lt of the disk-shaped element located about the major axis.
The peripheral edges of the vanes cooper~le with the nominally adjacent inner surfaces of the catheter to control the fluid flow II.e~through. P,~ ~ly, the inflow 20 vane is ~d~rted to be di ,cl--~ out of the control plane when a fluid pressure di~erer,lial is devGloped in the tubular element based upon a higher pressure in the proximal end than in the distal end in excess of a first pred~te",lined value. The outflow vane is adapted to be ~isF 19 ~e ~ out of the control plane when a fluid pressure Ji~l.2rential is dev~ ~eF ~ ~ in the tubular e' e ne"l base upon a higher pressure in the distal 25 end than in the proximal end in excess of a second predeterrnined value. The inflow vane is suLsl~nti&lly res;al~nt to flow of fluid from the distal end to the proximal end, and the outflow vane is suL, .t~lially resi ,l~"l to flow of fluid from the proximal end to the distal end.
In ~.otl-er aspect of the invention, the assembly may include a disk-shaped 30 element which is affixed to the interior of the tubular ele.,.enl at all points along the periphery of the disk-shaped element. The inflow vane is defined by an arcuate slit in the inflow portion and the outflow vane is defined by an arcuate slit in the outflow portion.

wo g~,~6,32 2 0 9 1 5 6 i PCr/USsl/06486 Generally, the valve asse",bly is nominally disposed to prevent fluid flow in the tubular element wh~ere there is substantially no fluid prsssur~e .JirrQr~n~&l across the valv,e ~ssel)~bly.
Brief DescriPtion Of The D,c,~ s These and other advantages of the presenl invention will be more fully under~lood by r,ference to the f~llQv.ing detailed descri~tion in conjunction with the dl~.ched drawing in which:
FIG. 1 is a sidle cross-section of a catheter seylllenl incG,i,or~ti"g th~e present invention;
FIG. 2 is a cross-section of valve asser"bly 25 through plane 26 of FIG. 1;
FIG. 3 is a side-cross section of a c~ll ,eter ey"~ent i, ~CGi IJOrdi;l Ig ail B~il6l 1~ /e embodiment of the present invention;
FIG. 4 is a cross-section of valve assernbly 125 through plane 126 of FIG. 3; and FIGS. 5A,B are perspective views of addilional prefer,~d embodiments of a valve a~sei"bly of th~e present invention.
~et~!led Descii~tion Of The Invention An embodiment of the presenl invention is shown in FIGS. 1 and 2 where c~ll,eler check valve assembly 10 includes a flexible tubular element 12, such as a catheter. Catheter 12 has a first or proximal end 14 and a second or distal end 16, and is clisposed when ;",plai,led in a patient, for inflow of fluid from proxi",al end 14 to distal end 16 into the palierlts bloodstream, and for outflow of fluid from the patient from distal end 16 to proximal end 14 to a connected flow device, such as a syringe.
Catheter 12 further includes an interior cylindricai wall sb-ucture 18 which axtends ~long a centrai axis A and thus defines a bidir~1ional fluid flow path. Th~ catheter is prt~ bly formed of ~i~compalivle malelial such as silicone or polyu,~U,~ne.
Coupled to catheter interiorwail 18 is a noi~inally planar bidirectional valve asselnbly24. For the circular cross-section c~U,eter of FIGS. 1 and 2 the valve assem~ly 24 is generaily defined as an elliptical disk-shaped element 25. With Jirrer~r,l cathetercross-e~1ions however,thQdisk-shapedF'en~i.tmayhavQa CGI I~5pondingly dirr~,~r,l shape.
Tha valve assei"bly nominaliy lies in a control plane 26 at an st'i1ue angle to centrai axis A. Valve assembly 24 is generaily resi~l~r l to fluid flow except as pel",itled WO 92/06732 ~ = PCI-/US91/06486 by a valving arrangement such as described beiow. Valve assembly 24 is pleIer~hly formed of a resilient material, such as silicone or polyurethane.
The disk-shaped '~mer,l 25 of asse" Ibly 24 extends along two disk axes normal to the catheter central axis A. These two disk axes include a major axis 30, and a 5 minor axis 32, where these axes are no~al to each other, sub~l~r,lially coinciding with the major and minor axes, respe~ti~/ely of the ellipse defined by el~,Y)e, h 25. A first disk peripheral portion 44 and a second peri~he,al portion 46 of the pe,i~,hery40 of ~ .
disk-shaped elerr)erlt 25, as respe.;ti~/ely located about the minor axis 32, are amxed to the interior 18 of the catheter. A third portion 48 of the disk peri~he,y 40 defines an 10 inflow vane 56, located about major axis 30, which is i~pl~c~~~le in a first direction 50 from the proximal end 14 to the distal end 16 generally along the central axis A. A
fourth portion 52 of periphery 40 defines an oufflow vane 58, located about major axis 30, which is displ~-e-hle in a second direction 54, opposite to the first direction 50, also generally along the central axis A.
Hence, inflow vane 56 is adapted to be displ~^ed out of the control plane (as indicated by the deflected vane 56' shown in phantom in FIG. 1) to open a fluid flow path 53 when a fluid pressure JirIererltial is developed in the ~ll ,~ter with a suf,.- ently high pressure in the proximal end 14 and sufficiently low pressure in the distal end 16.
As well, the outflow vane 58 is adapted to be disFl~^ed out of the control plane (as 20 i"~ c~ by the deflected vane 58' shown in ph&lholll in FIG. 1) to open a fluid flow path 55 when the fluid pressure diIIerer,lial is developed in the catheter with a sufficiently higher pressure in the distal end 16 than in the proximal end 14.
Inflow vane 56 is defined as an arcuate section 48a of the disk which pivots ~bout a pivot axis 48b and outflow vane 58 is defined by an arcuate section 52a which 25 pivots about pivot axis 52b. Location of axes 48b, 52b determines the height H1, H2 of vanes 56, 58. In the sense of the vanes being lever arms, heights H1, H2 determine the amount of clefl~ction (deflect~l ility) of the respective vane for a given fluid pressure and flexibility of the m&t~,ial of valve assembly 24.
As well, scGri"gs 60, 62 on disk 25 opposite to the side of the disk on which the 30 vane 56 or 58 d~le~t-, and along a respective deflectiQn axis 48b, 52b, also may be eillpl~yQd to e~ - ' `;sh flexure regions which regulate the ~iefle~tAbility of the respecti./e vanes 56, 58. Furthermore, it is possible to select .lifI~:re,h depths of scorings 60, 62 and diIlerent vane heights, H1, H2, such that vanes 56, 58 will deflect di~Ierer,ll~
.

WO 92/06732 2 0 91~ 61 -6- PCI/US91/064K

, ~
according to their resulting respective defl~cts~hilities. Consequently, a bidire.:tional valve may be obtained having a high prsssure direction and a low pressure direction.
The advantage of this two level effect is that infusion therapy may bs tailored for use with special ~sp,car~al.Js such as pumping devices. As well, valves may be opli.,.ked for 5 varying pressures at the point of implant or for use with fluids of di~f~r~.lt viscosiIiQs (i.e.: blood or water) or for use with a variety of infusion devices (i.e.: pumps or bags).
r~f~ ly, the inflow vane is suL~t~lt;&lly r~s;slLrlt to outflow of fluid from the distal end toward the ,cro~i...al end 14, and the outflow vane is substantially r~si;itant to o~nflow of fluid from the proximal end 14 to the distal end 16.
In an r:te.. ~li./e embodiment of the invention, as shown in FIGS. 3 and 4, avalve assembly 124 of catheter check valve asser..bly 100 includes an ellipticaldisk-shaped element 125 which lies in control plane 126 at an oblique angle to call eler central axis A. The entire periphery of disk 125 is affixed at respective locations along the interior wall 118 of catheter 112. Hence this valve assernbly 124 is generall 15 resisl~,l to fluid flow in the c~ltl-eler except as pe-itled by vanes 156, 158 as desc-iL,ed below. The catheter has a proximal end 114 and a distal end 116. The catl.e~er is shown in FIG. 4 as circular in cross-section, but elliptical or other cross-sections are also within the scope of the plese,.l invention.
In this embodiment, Slit 148 piercing entirely through a section of disk 125, creates a flexible flap or vane 156. Slit 152, piercing entireiy through another section of disk 125, creates a flexible flap or vane 158. Vanes 156, 158 are adapted to be d~lected out of the control plane 126, but in opposite directions, generally along central axis A.
Slit 148 is defined by two edges 142,144 formed in valve member 125, and slit 152 is formed by edges 145,146 also formed in valve member 125. These edges are nominally subsl~ltially parallel to the central axis A. In FIG.4, both vanes 142 and 152 are shown in an open position. This is for ease of description only, since it will be appreciated that the valve assembly is generally intended to G,oer~te with one valve or both valves closed, but not with both valves open.
Slit 148 and vane 156 are configured such that inflow of fluid along direction 150 (see arrow 150) impinging ~gainst inner wall 134 of vane 156 will deflect vane 156 (as shown in dotted outline) along the direction 150 away from control plane 126, and thereby opening a fluid flow path (see dotted arrow 136) for the flow of fluid (see dotted WO 92/06732 2 0 9 i tS 6 1 Pcr/us9l/06486 ~ ~ .

, arrows 138) in the direction 150 from proximal end 114 to distal end 116. The amount of ~leflection of vane 156 is a function of the fluid pressure ~ arentiaJ on the proximal and distal sides of disk 125 and the d~le~l~hility of the vane.
Vane 158 is similarly configured such that outflow of fluid (see dotted arrows 168) along direction 154 (see arrow 154) is caused by fluid pressure mounting up on the outer wall 166 of vane 158 and de9~ ~ing vane 158 toward proxi",~l end 114 (as shown in dotted outline) in the direction 154, opening a fluid flow path 176 for flow of fluid (see dotted urows 168) also as a function of the fluid pressure .lif~ererlti&l and vane d~llectAbility.
In this embodiment vane deflect~hility may be col It,olled by controlling the arc length of slits 14~,152, and also by scoring the disk as in the manner earlier described with respect to the embodiment of FIGS. 1 and 2. nefle Pbility may also be reg~ ~'qted by varying the thickness of the disk, i.e., having a thicker (harder to deflect) inflow vane than the outflow vane for sxample.
It will now be appreciated that in view of the simplicity of the present invention, a respecti.ls valve asser, Ibly may be employed in each lumen of a multi-lumen catheter, so as to afford independent bi-directional control to each of the lumen and in which case FIGS. 1-2 and ~4 will be under:,lood to show one lumen of a rbspe.1i./e multiple lumen catheter.
While a ~enerdlly planar valve ~sser"bly has been described, an S-shaped or other non-planar or non-sy",rnetrical valve assembly may also be employed within the invention, and therefore ~iscuscicn of a control plane may be u"der~lood as generally encG",passi"g a control plane or a nominal control plane.
In two further prefe"ed embodiments, as shown in FIGS. 5 A,B, the valve ~ssembly takes the form of an ~l~ng~le flexible ~leh ,enl 224 or 324, nominally mounted relative to a respective control plane 226, 326 to form vanes 256, 258 and vanes 356, 358, resp~ti~ely. Vanes 256, 258 and vanes 356 358 function generally as do vanes 56, 58 of FlGs. 1 and 2.
More puticularly, as shown in FIG. 5A, element 224 is affixed to the interior ofc~tl,eter 12 only at its edge pol tions 244, 246 to create vanes 256, 258. Vanes 256, 258 form mechanical closures against the catheter interior.
In FIG. 5B, eleh-er,t 324 is a contoured structure prefe"A~ly molded from a flexible material (such as UM-type silicone rubber), and is affixed to the interior of WO 92/0673t 2 0 9 ~ PCI/US91~06486 ~ll .~ter 12 along a first pair of the element's sides 344, 346. The opposecl ends 341 343 of element 324 are mechanically urged aga nst the interior of tha catheter to create vanes 356, 358. rl6x Ie element 324 is plef~., bly formed thinner than the wall ll.ioh-.ess of the catheter in which it is to be used. Hence, an fi emenl having a 5 ll ,. ~hl ,ess of about 0.010 0.020 inches can be benEf;-ially mated with a catheter having a wall lhi~k. ,ess of about 0.020-0.025 inches, for ex~-"r'e.
The pr~sent invention may be embodied in other speci~:c forms without dep~ li"g from the spirit or essential char. _t~ lics thereof. The pr~serlt embodiments are lher~rore to be consider~d in ~ll r~spe-;t~ as illustrative and not re:,l,i~ti~e, the 10 scope of tha invention being i"-l c~lecl by the appended claims rather than by the ~re;,oi.,g des~ Jlion and all changes which come within the meaning and range ofequivalency of the claims are II,e,~fore i"lended to be er"braced therein.

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A valve catheter comprising an elongated, flexible tubular element extending along a central axis and having a proximal end and a distal end and being adapted for flow of fluid between said ends, a valve assembly coupled to the interior of the tubular element, said assembly generally defining a control plane which intersects said central axis at an oblique angle, said assembly having a flow portion disposed to lie in said control plane whereby said assembly establishes a fluid seal across the interior of said tubular element at said control plane, said flow portion including a flexible vane having its periphery affixed at least in part to the interior of sald tubular element and being positioned between said intersection of said control plane with said central axis and said ends and adapted to be deflected out of said control plane in response to the establishment of a relatively high fluid pressure at one of said ends and a relatively low fluid pressure at the other of said ends.

2. The catheter of claim 1 wherein said element is adapted for bidirectional flow of fluid and said valve assembly further comprises a bidirectional valve assembly, said flow portion having an inflow portlon and an outflow portion nominally disposed to lie in said control plane, said inflow portion including an inflow vane positioned between said intersection of said control plane with said central axis and said distal end and adapted to be deflected out of said control plane toward said distal end in response to the establishment of a relatively high fluid pressure at said proximal end and a relatively low fluid pressure at said distal end, and said outflow portion including an outflow vane positioned between said intersection of said central plane with said central axis and said proximal end and adapted to be deflected out of said control plane toward said proximal end in response to the establishment of a relatively low fluid pressure at said proximal end and a relatively high fluid pressure at said distal end.

3. The catheter of claim 2 wherein said bidirectional valve assembly comprises resilient and deflectable portions such that said inflow vein is displaceable by flexing in a first direction generally along said central axis and said outflow vane is displaceable by flexing in a second direction opposite to said first direction generally along said central axis.

4. The catheter of claim 2 wherein said tubular element defines a substantially circular cross-section interior region extending along said central axis and said assembly includes a flexible elliptical disk-shaped element which nominally lies in said control plane.

5. The catheter of claim 4 wherein at least a part of the periphery of said elliptical disk-shaped element is affixed to the interior surface of said tubular element.

6. The catheter of claim 5 wherein said elliptical disk-shaped element defines two disk axes normal to said central axis, said two disk axes including a major axis and a minor axis which is normal to said major axis, the periphery of said elliptical disk-shaped element located about said minor axis being affixed to the interior of said tubular element along a first portion and a second portion of said periphery, a third portion of said periphery defining said inflow vane located about said major axis and being displaceable in a first direction generally along said central axis, and a fourth portion of said periphery defining said outflow vane located about said major axis and being displaceable in a second direction opposite to said first direction generally along said central axis.

7. The catheter of claim 6 wherein said inflow vane is defined by an arcuate segment of said disk-shaped element located about said major axis.

8. The catheter of claim 6 wherein said outflow vane is defined by an arcuate segment of said disk-shaped element located about said major axis.

9. The catheter of claim 6 wherein said periphery first portion and said periphery second portion are generally positioned in opposition to each other.

10. The catheter of claim 6 wherein said periphery third portion and said periphery fourth portion are generally positioned in opposition to each other.

11. The catheter of claim 2 wherein said valve assembly is entirely internal to said tubular element.

12. The catheter of claim 2 wherein said control element is affixed to the interior of said tubular element at all points along the periphery of said disk-shaped element.

13. The catheter of claim 12 wherein said inflow vane is defined by an arcuate slit in said inflow portion and said outflow vane is defined by an arcuate slit in said outflow portion.

14. The catheter of claim 2 wherein the valve assembly is nominally disposed to prevent fluid flow in said tubular element where there is substantially no fluid pressure differential across said valve assembly.

15. The catheter of claim 14 wherein the inflow vane is adapted to be displaced out of said control plane when a fluid pressure differential is developed in said tubular element based upon a higher pressure in said proximal end than in said distal end in excess of a first predetermined value.

16. The catheter of claim 13 wherein the outflow vane is adapted to be displaced out of said control plane when a fluid pressure differential is developed in said tubular element based upon a higher pressure in said distal end than in said proximal end in excess of a second predetermined value.

17. The catheter of claim 2 wherein said inflow vane is substantially resistant to flow of fluid from said distal end to said proximal end.

18. The catheter of claim 2 wherein said outflow vane is substantially resistant to flow of fluid from said proximal end to said distal end.

19. The catheter of claim 2 wherein said catheter includes multiple lumen, at least one of said multiple lumen comprising said tubular element.

20. The catheter of claim 2 wherein said bidirectional valve assembly is generally planar.