CA2110982C - Vascular occlusion removal devices and methods - Google Patents

Abstract

A catheter (10) for removing vascular obstruction(s) is disclosed. The catheter employs a configuration comprising generally coaxial, rapidly rotatable drive cable (14), fluid output lumens or channels (48), and fluid input lumens or channels (30). The drive cable is fixedly coupled to an elongate head (16) so as to permit the head to be rapidly rotated by the drive cable. The head includes flats or impellers (26) which, when rapidly rotated, generate a zone of turbulence or a vortex adjacent the vascular obstruction. The turbulence generated by the device tends to break up or dismantle the obstruction. The fluid input and output mechanisms permit fluid to be delivered to the vicinity of the obstruction and debris from the obstruction to be removed. Methods for removing vascular obstructions are disclosed. Preferably pulsatile turbulence generation is employed.

Description

WO g3i00~19 PCI/US92/~220 ~ .
211~9~2 VASCUI,AR OCCLUSION REMOV~ DEVICES AND METHODS

Backqround of the Invention Field of the Invention This invention relates to vascular occlusion removal or thrombus dissolution or destruction devices. More specifically, this invention relates to thrombus d-ssolution devices or catheters for insertion in body vessels for removing obstructions therefrom. Yet more specifically, this invention relates to apparatuses or thrombectomy devices for removing vascular obstruction~
such as thrombi by the creation of turbulence or a vortex near or adjacent to an obstruction or occlusion.
Concurrently or sub~equently, suction or aspiration , . .. . .
removal of the resulting disiDtegràted obstruction material is described.

Description o~ the Prior Art . .
The removal of harmful blockages from vessels, ducts r : ' ,' ,.; C- -- ;
or pas~ages within the body is typically accomplished by : .,, , -- . - . - . . . ...
one of several techniques. One technique utilizes a~ .
-, . .

treatment catheter equipped with two inflatable balloons.
The inflatable balloons are used to seal off a ~- . - ,. . .
co~stricted area in a duct or passage such as a blood vessel. An inlet member is provided within the catheter WO 93/001i9 -~- l'CI'/1~1~!;220 2110982 '' - -for supplying a suitable ~olvent, such as a thrombolytic agent or solution of digestive enzymes, to the area delimited by the two balloons. An outlet member is provided for removing the dissolved material from the site of the restriction. In addition, a second supply channel is provided for allowing the blood or other body fluid to bypass ~he delimited area, thus preventing a complete vascular or coronary obstruction. A second techniquet balloon angioplasty, involves deployment of a balloon catheter within the obstructed vessel 80 that, when the balloon is inflated, the con~triction or obstruction material is compressed against the vessel w~
A problem with the above techniques is that they may cause blood vessel wall damage.
Another more recent technique, k~own as laser angioplasty, uses laser energy to vaporize an obstruction. In this technique, the catheter, which is mounted for rotation and translation about a filament, has a pair of abutments disposed on it~ distal end. Also included on the distal end of the catheter is a bladder which, when inflated, causes the abutments to bear again~t the inner surface of the blood vessel so that the space between the abutments defines a working chamber for delimiting the area around an obstruction. A fiber optic WO~3/00119 'J~ PC~VS9~2J05220 "..
21i ~9~2 connected to a source of laser energy extends through the catheter, with the distal end of the fiber optic being disposed in one of the abutments. In addition, a suction port is pro~ided between the abutments for removing disintegrated material from the delimited area. Severing means such as a blade or a heated element also may be included for severing and releasing material which is not vaporized by the laser. As with balloon angioplasty, la~er angioplasty can result in damage to the blood ve~sel itself.
Another technique for removal of blockages utilizes what is generally referred to as an atherectomy device or catheter. An example of this type of device is disclosed in ~.S. Pat. No. 4,63l',052 to Kensey. The Ken~ey IOS2 patent de~ice comprises a bladed cutting head which is rotated by a turbine drive to cut away occlusions i~ a body vessel. This Kensey '052 catheter presents the 'possibility of vessel wall damage if its rotary head were ~- to be~; deflected by: an especially hard portion o~ an occlu~ion. ~ - :' ":~ ' ' ' ' - -- United States Patent 4,9S0,238 issued to Dennis E.
Sullivan describes a hydro-rotary vascular catheter which i8 a variation' on the balloon angioplasty technique described above. Sullivan discloses a catheter having a rota~y, fluid-directing head and isolation means, e.g., w~93/oo1i9~ P~T~U~92/05220 21103~

balloons, which are positioned upstrsam and down~tream of the obstruction. After being positioned, the upstream and downstream balloons are inflated with the patient's blood and a prPssurized flushing fluid, re~pectively, to seal off the obstruction. Flu~hing fluid i8 ejected from the rotary fluid-directing head of the Sulli~an catheter which causes the head to rotate. This rotation creates turbulence which, in conjunction with the fluid streams themselves, iB said to break down the vessel obstruction.
A return channel permits debris to be removed from the constricted area. The Sullivan device is ~tructurally complicated and ha~ the admitted drawback of occasionally requiring the use of digestive enzymes or other olvents such7as;those used in ~ome forms of va~cular treatment discu~6ed above.
United States Patent 4,749,376 to Kenneth Kensey et al. discloses a "Reciprocating, Working Head Catheter".
-The-catheter of Ren~ey et al. compri~es an els~gated drive wire- extending through the catheter body and a motion transtator located at the distal ~nd of the : catheter. The-drive wire is rotated at high speed and the tra~stator translates the rotary motion into reciprocating motion. In this manner the working head is rotated and reciprocated. This motion, in conjunction with a fluid, permits the catheter to open the body WO 93iOOil9 ? PCI~/US92/~05220 vessel in which it is inserted. No aspiration or removal of debris is disclosed or suggested in the Ken~ey et al '376 paten~.
United States Patent 4f445r509 to David C. Auth di~closes a rotating head cutting tool recanalization catheter having spirally shaped cutting flutes with hardness-differential cutting properties. Plaque and other obstruction~ are alleged to be removed from organic structures without damage to normal tissue. The cutting apparatus of ~he Auth et al. patent is disclosed to be rapidly rotated withîn the blood yessel of a patient by m~ans of an external torque-generating device, e.g., an electric motor. In operation, then, the cutting tool is ~dvanced against a blood vessel lesion or obstruction and the obstructi~n is differentially cut. Th~ apparatu~ of Auth et al. has a fluid port in communication with an external suction~devi~e so that blood and debris from the cutting operation can be removed from the cukting ~ite.

United States Patent 4,631,052 to Xenneth R. Ken~ey discloses a rotating head or recanalization catheter ~';which-i~advanced through the body-passageways to the site of a restriction. The apparatu~ of the Kensey '052 patent i~ disclo~ed to operate by cutting or by mechanically beating or otherwise agitating or disturbing ~W~93/00119~ PC~/US92~05220 ,, ~

the blockage material to form an opening. A perfusion structure is provided which provides oxygenated fluids, drugs, contrast media or dyes into the occluded or blocked passage way. United States Patent No.
4,795,438 also to Kenneth Kensey discloses a method and apparatus for forming a restriction in a ~es~el, such as a fallopian tube. No removal of unwanted vascular obstructions is disclosed or contemplated in the ~ensey '438 patent.
Uni~ed States Patent 4,784,636 to Mark A. Rydell di~closes a balloon atherectomy catheter. The Rydell '636 patent apparatus has an angular cutting tip fixed to the distal end of an elongated dri~e tube. A separate rotational drive mech~ni~ is coupled to the drive tube to rotate the- drive tip. Provision is made for introducing fluid through the loop of the guide catheter for inflating the balloon and for aspirating blood and loose particles away from the occlusion site. The balloon mechanism i8 used primarily to retain the di~tal end of the catheter a~sembly in place near the oc lu~ion to pe~mit the cutting operation to be performed. .
United States Patent 4,715,538 to Horst Lingnau.and ~nited Stat~s Patent 3,120,326 to Ernie D. Willhoite disclose jet nozzles and rotary spray de~ices, respectively. The inventions of Lingnau and Willhoite WO g3iOfl1i9 '' ' PCr!U,,Sg2/~5220 . ~

are useful for cleaning narrow tubular parts, such as pipes, or for drilling though soft materials by means of j et or spray nozzles. These references make no mention of possible medical applications of these inventionsO
Recently, a catheter has been de~cribed which comprises a distal end header in fluid communication with a plurality of pro~ l end- or backward-directed high pre~sure jets. Fluids are fed to the header through the body of the catheter by means of an off-center input pipe or lumen. The high pressure jet~ direct fluid backward away from the tnrombus, and thereby create a vortex which allegedly tends to remove it. No rotation of the header i~ possible.
~ one of the above patents alone or in combination disclo~e or suggest the invention of the present application.

- - Brief Summar~ of the Invention Briefly, in one a~pect, the present invention i8 a cath¢ter for removing an obstruction in a body vessel which generally involves no cutting or mechanical destruction of the sbstruction or deposit. A device of thi~ invention effectuates removai of the obstruction or deposit by thP creation of fluid turbulen~e or a vortex ~ s~ PCT/US92/~2~

in the region immedia~ely adjacent the obstruction.
A~piration of the resulting detritus or debris, to remove it from the obstruction site, is contemplated. By application of this invention, an obstruction is removed from the vessel without injury or damage to the surrounding vessel walls. In most instances there is no need for physical contact between the obstruction and any part of this invention in order for the vessel obstruction to be destroyed and removed.
A catheter of the present invention comprises a flexible, tubular, or elongate sleeve or catheter body having distal and proximal ends. The sleeve, catheter body, or external sheath has drive means extending therethrough so asjto project from the distal end. The drive means, such as a drive cable or drive wire, can be utilized to assist in guiding or pushing the catheter through the torturous path of the vessels of a body to a point where the.distal end of!the catheter, e.g., the head meAn~t is located near ths obstruction. As such, the drive. ~e~n~ ,..both..flexible and, preferably, steerable. The drive me~n~ of the present invention mu~t be rapidly rotatable within the catheter body. The drive means also comprises a head means or a tip fixedly mounted on its projecting end. ..
The head means comprises a substantially smooth, ' W0~3/~ Pcr/U~92/g5220 ,. ~

bulbous or ellipsoid head having a base or neck. The head ~eans is mounted on the drive means at the base of the head so as to be rapidly rotated thereby. The head means generally includes a turbulence or vortex generating means. The turbulence generating means g~nerally is disposed at the base or neck of the head between the distal end of the catheter body and the head it~elf. A turbulence generating means of this inventiont such as a plura~ity of facets, veins, Lmpellers, or flats, i~ disposed at or adjacent the baae of the head so as to create turbulence when the drive means, and hence the head means, is rapidly rotated, e.g., by an external source of rota~ional energy such as an electric motor or compressed air.
A catheter of the present invention further comprises means for delivering a fluid or fluids proximate the turbulence generating ~eA~s and fluid and debris or~;~detritus recovering means also lorated ! proximate th~- turbulence generating r~n~ The fluid ~delivery and recovery means can be used to deliver and retrieve essentially any fluid-materîal to the distal, :working end of the catheter. The ~luid recovering means permit~ debris and particles generated from the obstruction to be easily and conveniently removed from the site thereof. The fluid delivery and fluid recovery -W0~3/0~19 ~ PCT/US92/0~220 ~

2111~9g2 ~... ,., ., ' means may be operated simultaneously or sequentially.

The fluid delivery and recovery means of the invention further comprise channels, lumens, input and output orifices or ports~ The channels are ge~erally coaxial and run through the catheter body within the sleeve. Sources of pressurized fluid, usually external, are contemplated. The debris recovery means al~o generally include6 an external vacuum source or an aspirator.

In a pr~ferred practice, a device of the present invention is constructed ~o as to permit it to be used with a guide means ~uch as a guide wire. Guide wires, especially steerable guide wires, are u~ed to lead the catheter to a pre~iously identified obstruction ~ite.

U~ing conventional techniques, a guide wire is ~teered or directed through the operant ve sel and it~ distal end or tip is located adjacent the vessel obstruction. A

catheter of thi~ in~ention-then is slid over the guide wire o~theipoint-iwhere the head means also is located ~adjacent the-obstruction,~overlapping or in contact with the distal tip or end of the guide wire. Guide wires may be trea~ed, e.g., by coa~ing with-slippery~materials, to make the sliding process easier. If used with a guide wire, a device of $his invention will be hollow colu~lising an inner hollow lumen, of approximate guide , . . . , . . . ,. .;, ~.... . . . . .

W093iO0119~ PCT/US92/0~220 211~932 wire diameter, which permits the catheter easily to slide over the guide wire to the location of the vascular ob~truction once the distal tip of the guide wire has been steered thereto.
In a method of the present invention, the location of a vascular or vessel obstruction is identified. The distal end of a catheter of the above structure is steered to the a location adjacent to, or ~ear the previou~ly-located obs~ruction, preferably using a guide means as described above. The distance between the di~tal end of the catheter, i.e., the head means, and the obstruction should permit the turbulence generated by the ~urbulence generating means, preferably in conju~ction with fluid delivery, to impact and erode the obstruction.
~he:catheter, via the drive means, i8 then con~ected or coupled to external rotation means, external debris removal means, e.g., an aspirator, and external f?uid i~p~t means, e.g., a pump. The drive means then is rapidly rotated~by -~ the:~external rotation means simultaneously~ or in- conjunction -with~ delivery of pres~urized fluid adjacent to the site of the obstruction and proxLmate to the turbulence generating mean~. The pressurized incoming or input fluid can interact with, or impinge upon, the turbulence generating mean~ to create a vortex or zone of turbulence which tends efficiently to W0~3/00119'-~ PCT/US92/05220 21~982 ~ t remove the obstruction without damaging vessel structures. The external debris removal means (e.g., suction) may be simultaneously or subsequently activated 80 as to remove particles generated from the obstruction by the ~urbulence. In thi~ manner, removal of the ve~sel obstruction, and especially debris therefrom, i~
accomplished. It will, of course, be necessary for the rates of output and input of the fluid input means and the debris recovery me~nS to be adjusted so that the body vesselis neither collap~ed nor expanded.
Throughout the description of the present invention, the terms "vessel" or Ubody vessel" are intended to be broadly construed to include es~e~tially any vessel, including veins and~ arteries, whether they are of a coronary or peripheral- nature. Noreover, while ~pecifically directed toward human body ve~sels, removal of obstructions ~rom essentially any body vessel is contemplated herein. ~ -~L~ ;-Brief Description-of the Drawin~s~ ~
-~ FIG.il is a schematic plan view of an embo~;ment of the present invention; --- FIG. 2 is an enlarged fragmentary view of the tip segment or distal end of the embodiment of the invention ~hown in FIG. 1.;
FIG. 3 is a sectional view of the device of FIG. 2 WO'93/00119~'' PCT/~S~2/05220 ~ 3982 taken along line 2-2;
FIG. 4 i~ a view along the line of that of FIG. 3 rotated 45 degrees;
FIG. 5 and 5A are view of the de~ice taken alony line 5-5 of FIG. 2;
FIG. 6 is a view of the device tak~n along line 6-6 of FIG. 2;
FIG. 7 i~ a cross sectional view of the device illustrating the cro8s sectional relationships between the various coaxial components.
FIG. 8 i~ a detailed depiction of the aspiration output port a~embly ge~erally indicated in FIG. 1.
FIG. '9 is a partial se~tion view of a fluid injection asse~bly al60 generally depicted in FIG. 1.
FIG. 10 is-an embodiment of the present i~vention employing a non-removable guide wire;
FIG. '11 i~ an embodiment such a~ in FIG. 10 employing a--removable guide wire;
:~' FIG.-~2~-is a cros~-section view of an apparatus ~uch.
a~-that shown'in FIG. 11;
FIG, 13 ~is the apparatus shown in FIG. 12 but rotated approximately 45~ from the section view shown in FIG.-12;-~ IG. 14 is a cross-sectional view taken along line 14-14 of FIG. 12;

-w0~3/~oi19 ''i PCT/U~92/052~0

2~ iO~S2 FIG. 15 is a cros~-sectional view taken along line 15-15 of FIG. 13;
FIG. 16 is a cross-sectional detailed view of an -alternative e~bodiment of the head of nose of the present invention;
FIGS. 17 and 18 are side and axial view~ of alternative turbulence generating mean~ of the present inventionO
FIGS~ 19 and 20 are side plan views of the distal portion of further embodLments of catheters of the present invention.

Detailed DescriPtion of the Inventioll Thus there is shown in FIG. l a schematic plan view showing-the major components of an-apparatus, catheter, assembly, device or article 10 of the present invention.
In this embodimént of the invention, apparatus lO
compri~es a flexible, tubular sleeve or catheter body 12 having distal and pr~ l.ends.~ The distal end of sleeve 12 is the right-most, or working portion of the de~ice depicted in Fig.1. Generally spe~king, "the di~tal end" of sleeve 12 is that portion of sleeve 12 in the ~icinity of any vessel obstruction which is to be removed by operation of an apparatus of this invention.
Sleeve 12 (and the catheter~ may be up to several feet ' !~ - ''- :t~; . PCTlUS~2/05220 2 ~ 3 2 in length, depending upon the distance between the ves~el ob~truction, the ~ite where the catheter enters the body, and the distance to any required external fluid management sy~tems.
As i~ described in greater detail below, running through sleeve 12 is a drive means. Drive means, in one e~bodiment comprise~ a torquable, flexible, drive cable 14 which is rapidly rotatable, and at least partially steerable or pushable. Fixedly attached to drive cable 14 so as to be rapidly rotated thereby is a head ~eans or a tip. In this embodiment, the head means 16 comprises a substantially solid, preferably metal, tip or head 16 which tapers to a turbulence generating means (not depicted in FIG. 13 loc~ted between the distal ~nd of sleeve 12 and head 16. (A preferred turbulence generating means is more completely described below.) Drîve cable 14 is the means by which the head means of thi~ inventio~ i~ rapidly rotated. - .
'- - Also shown in FIG. l-is a-fluid input port-18 which i8 a portion of the fluid delivery ~e~n~. ~.(Fluid output ports-are located adjacent the turbulence generating means substantially coaxial with sleeve 12 and are not depicted~in FIG. l.) -Aspiration output port 20 i8 a part of the fluid and debris reco~ery means, further details of which are included ~elow. Aspiration output port 20 w~ s3Joo~is Pcr~;/u ~s~,s2$/,0s2~20 i~ ~onnected ~by means of an interior channel~ to aspiration input port 21 which is located adjacent the turbulence generating means. In this preferred configuration, aspiration input port 21 is located and extends through the wall of sleeve 12. A plurality or multiplicity of aspira~ion input ports are within the contemplation of this invention. Rotatable fluid seal 22 permits rapid rotation of drive cable 14 within sleeve 12 while the dri~ cable is coupled to an external source of rotational energy (not shown) such as an electric motor or a source of compressed air. Drive cable 14 of ca~heter 10 would normally be connected to an external electric motor ~y means of, for example, a flexible coupling 24. Drive me~n~ or cable 14 run~ through the entire length of catheter 10 and is substantially coaxial therewith~
FIG. 2 is an enlarged fragmentary view of the tip ~egment or portion of the apparatus shown in FIG. 1 with parts cut:away.-.As ~hownj the distal end of sleeve 12 has:bulbous h~ad 16 projecting therefrom. As shown, head 16 i8 substantially smooth i.e., having no cu~ting or ~hearing structure intended physically to cut or erode an obstruction were it- to come into contact therewith.
Between head 16 and slee~e 12, at the base or neck 25 of the head, i~ a turbulence generating means which, in this WO93/00119 ' PCr/US~2~ 20 . ~
2 ~

embodiment, compri~es flats or facets 26. Head 16 tapers or "necks down" to create and define flats or facets 26.
Facets are a preferred turbulence generati~g means of this invention. However, many other possible configurativns at the neck or base of head 16 could be employed to create turbulence. For example, head 16 could be hollow, cone-shaped, or of a mushroom configuration. The "~tem" of a mushroom-shaped head would then be connected to the drive means to permit rapid head rotation. Within and protected by the mushroom "head" would be an interior space in which radial turbulence generating blades, bins, f~cets, or other projections could be located.
Drive cable 14 projects coaxially through sleeve l2 and i8 fixedly attached to head 16 so a~ to permit head 16 to be rapidly rotated ther~by. Output ports 28 project throuyh bushing housing 36, the arrangement of which is digcussed below. Output ports 28 dixect fluid output longitudinally toward flats~26 to ge~eratel.a particularly~preferred thrombus dis solution- ~one. ~: -Sidewall aspiration input port 21 i~ shown in FIG.2. A second pair of end-disposed aspiration input ports 28 also are illustrated. As long as either end-disposed or side wall aspiration input ports are provided, it is largely a matter of design discretion which is utilized.

Wo93/~Oil~ ~ P~rIUS~92,/,05220 ,, ~~
Q ~ 8 2 Sidewall and ~nd or end-disposed aspiration input ports, if both are employed, would preferably be in fluid communication with each other and ultimately (via an interior channel~ with aspiration output port 20.
Also shown in FIG. 2 is a flexible inner member fluid delivery or fluid containm~nt tube or lumen 30.
Fluid deliYery tube 30 i8 part of the fluid delivery means which includes fluid input port 18. The details of the fluid connection between fluid delivery tube 30 and fluid input port 18 are illustrated in FIG. 4. In FIG. 2, fluid delivery tube 30, drive cable 14, and sleeve 12 are all substantially coaxial~ While not required, it has been found that coaxial ~onstruction tends to be the -most space efficient, providing the 6mallest diameter catheter~ ~
FIG. 3 is a partial section view of the devi e of FIG. 2 taken along line 2-2. For purposes of clarity, head 16 (shown in other views) has bee~ remo~ed. Side wall--aspiration;:input- port~ 21 i8 shown to be ~in commnnication (via distal aspiration channel se~ment 32) with end-disposed aspiration port 28. Aspiration ports 21, 28 and distal- channel- segment 32 are in fluid communication with ~eA;~l aspiration channel segment 34.
Nedial aspiration channel segment 34 is in downstream fluid comml-n;cation with aspiration output port 20.

WO 93/00119 ' P~/US92/05220 21~09cd~ ~
1~ ' Shown in FIG. 3 is bu~hing housing 36 which cooperates with headed bushing 38 to permit drive cable 14 to rotate (on bearing surface 40). Bushing housing 36 is mounted on adaptor slee~e or lumen slee~e 41 at adaptor surface 42. Lumen sleeve 41 is, in turn, mounted on inner lumen or tube 30 at inner lumen surface 44. With this configuration, rapid rotation of drive cable 14 within coaxial inner lumen 30 is permitted.
FIG. 4 depict an article of FIG. 3 in partial ~ection, but rotated 45 degrees from the view of FIG. 3 to show more detail of the fluid and debris recovery means. Fluid output port 46 communicates with distal fluîd channel segment 48 and with the chAnnel withi~, Fluid delivered through inner lumen 30 to di6tal fluid channel 48 is delivered adjacent head 16 from output ports 46. The channel defined by inner lumen 30 is in fluid commll~;cation with fluid input port 18 on the proximal end of the apparatus.
~;;' FIGS. 5 a~d 5A-are-views of- a head mean~: of the device taken along iine 5-5 of FIG. 2.~ Flats o~-facets 26, -which merge with bulbou6, -ellipsoidal, ~mooth, substantially spherical or bullet-shaped head 16 are cl~arly shown. Flats 25 do not project beyond the circumferential profile of head 16. Flats 26 generate a particularly advantageous turbulence (for removing vessel ~WOg3i~0il9~'~ PCT/~S92/05220 ..
~110~2 ~

obstructions) in conjunc~ion with pressurized fluid axially or longitudinally emitting or delivered from fluid delivery ports 46 (such as are shown in FIG. 4~.
Fluid axially directed upon rotating flat 26 creates a preferred thrombus obstruction or di solution zone. The capability of controlled delivery of fluid to the turbulence generating means while it is in rapid rotation is a particular advantage of this invention. By adjustment of fluid presgure and rotation speed, it may be possible to adjust or to customiz~ the turbulence zone or thrombus destruc~ion zone to the type of vascular obstruction to be removed.
FIG. 6 is a view of the device taken along line 6-6 of FIG. 2. Fluid output ports 46 are shown in relation ~o aspiration input ports 21. Fluid emitting or emerging from the apparatus would exit ports 46 essentially perpendicularly to the plane of FIG. 6. Headed bushing 38 i8 shown to be mounted upon guide wire 14. ,.
;~FIG.~ 7 is ~a cross -sectional view~ of the device illustrating the schematic relationship between the various coaxial components. Sleeve, outer wall, or exterior sheath 12 i~ coaxial with inner tube, inner fluid tube or lumen 30. Between the outer sheath (or outer tube) 12 and inner lumen 30 is aspiration channel 34. Within aspiration channel 34 is drive cable "~
W~ 93J00119 PCI/US92tO5220 '.

2 ~ 2 or drive wire 14 which then defines fluid delivery channel 48. L~quids or fluids in fluid delivery channel 48 and fluids and debris in aspiration cha~nel 34 (in operation of the device) would be proceeding in opposite directions if the f luid output means and he f luid input means were simultaneously operated. Drive cable 14 optionally may be hollow, leaving an inner most channel or lumen 102 i~to which a guide wire could be slid.
FIG. 8 shows in detail the features of the aspiration output port assembly, as shown generally at arrow 20 in FIG. 1. The particular details are not critical to the invention, there being a number of design alternatives which would be within the ~kill of one familiar with thi~. art. As de~cribed above, drive cable 14: proceeds through the il~ustrated portion of the apparatus substantially coaxially with sleeve 12. Sleeve 12 comprises a flexible, Hytrel polyester material pre$erab1y having a wall thickness in the range of about 0.008 in.- to 0.012.in. :As- i8 more completely di6cussed below, the overall diameter of-sleeve 12 will largely-be deter~; ned by the size of the vessel into which the de~ice i8 to be inserted. It is a ~eneral design pref erence that the portion of the catheter to be in~erted in a vessel have the smallest overall diameter or profile consistent with its intended function.

~r~ i ~ . .. .

'-' , ' 21~03S2 ~3 Re~'d P~T/PTO 2 7 AUG 1993 Proceeding from the left of FIG. 8, there i~ shown a barb fitting 60. Barb fitting 60 i6 bonded to junctl'on block or header 64. Barb fitting 60 is not ssen in FIG.
1 hecau6e it i6 compre6sed within sleeve 1~ to permit connection of the a~piration output port assembly to the on tube segment 62 bod~ o~ the catheter. Junction block 64/i~ in-fluid communication with the interior of sleeve 12 ~o as to permit fluid and thrombus destruction products or debris to be removed, therefrom, e.g., by a~piration. Junction block 64 connects through female luer 66, to an external source of vacuum (e.g., an aspira~or) of sufficient strength to withdraw fluid and material from the device.
By meana of a male luer 68, back ring 70 and female luer lock adaptor 72 (and adhesive at 74) junction block 64 provides a vacuum and fluid tight acce~s to medial portion or segment 34 and distal portion or segment 32 (shown in FIG. 3) of the aspiration channel.
FIG. 9 shows, in partial section, the detail~ of fluid input or fluid injection port generally designated 18 in FIG. 1. A3 with the aspiration output port a~ embly of FIG. 8, a second barb valYe 80 i~ connected to a second junction block or header 82. Junction block 82 ~via khreaded fitting 84) is i,n fluid .communication with housing 86. Within housing 8S are ~OK rings 88 which are held in place by "Teflon" polymer bearings 90.

SUBSllTlJTE SH Er WQ'93i~0ii9'~ P~T/US92/052 ~
. 0 ~

External fluid acce~s to junction block 82 is by means of fluid input port 18.
The assembly of FIG. 9 permits fluid to be introduced around drive cable 14 (not shown) while permitting the drive cable to rotate. The plurality o~
"0" ring assemblies are used to decrease the likelihood that fluid would enter the catheter (at 18) and exit toward an external motor (not depicted) employed to rotate drive cable 14.
In FIG. 1, the assemblies of FIGS. 8 and 9 are shown to be separated by a segment of the catheter. One design alternative would be for these two assemblies to be placed next to each other, possibly in contact. In yet a~other e~bodLment, a single junction block mAn;fold~ or header could ~e employed to provide fluid and aspiration access to the respective channels of the catheter. Such a junction block or header would require separate fluid input and aspiration output ports in fluid co~mllnication with their respective ch~nnels within the tubular body of the catheter.
FIGS~ 10 a~d 11 depict an apparatus of this in~ention employing an optional guide means such as a guide wire 100. ~uide wire 100 would project through the inner most or center lumen of the apparatus shown at 102 in F~G. 7. Guide wire 100 ter~;n~teS in a radiopaque, wog3/oo~9l1 P~T/US~2/05220 ~1{i3~

atraumatic coil 104. By mean~ of fluroscopy, atxaumatic, radispaque coil 104 is used to steer the guide wire to the point where its distal end, tip, or head is located immediately adjacent the s~te of a previously identified thrombus. Guide wire 100 generally would have an outside diameter in the range of approximately 0.008 to 0.016 inche With such a small diameter relative to the average vessel diameter, the guide wire is very capable of following or being steered through the tortuous path of body vessels to the site of an obstruction. The two embodim0nts of FIGS. 10 and 11 differ primarily in that coil 104 in FIG. 10 is of a slightly larger diameter than center lumen 102 in head 16. The guide wire up to tip 104 is generally a solid core material. The material of guide wire 100 would be sufficiently flexible as well as suf~iciently stiff to permit the rest of a catheter of the invention to track over it once the guide wire has been advanced to, or possible through, the obstruction or stenosis site.~
A preferred guide wire for use with a catheter;of this in~ention is commercially available from the Lake Region Manufacturing Company, Inc. of Chaska, Minnesota under the trade designation ONTRAC~. After the catheter ha~ been directed to the site of the stenosis, the guide wire shown in FIG. 11 optionally may be withdrawn, W093/00i1g PCT/US92/U5220 2 ~

leaving the catheter in place next to the obstruction.
Alternatively, the guide wire may be left in place with the cathe~er slidably or rotatively di~posed thereover.
This is shown in FIG. 10. Of particular note is the fact that, in this embodiment, fluid output ports 46 are sh~wn to be disposed on turbulence generating means or flats 26. In other ~ords, fluid can be deli~ered from the face of the flats 26. Aspiration input port 21 is shown to be disposed in the ~ide wall of flexible sleeve 12.
FIG. 12 shows a partial-section view of an apparatus of FIGS. 10 or 11. FIG. 12 is a depiction of the device disposed along a guide wire 100. Guide wire 100 extends coA~i~lly through the catheter which is coaxially mov~able therealong. Fluid output ports 46 are also disposed in flats 26 in this embodiment. Fluid output ports 46 commtln;cate with a header 110 which is located interiorly in head or bulb 16. Header 110 comm-lnicates with-internal channel or lumen 112 which would, it~el~, b~ in~fluid communication with -an external source of fluid via input port~l8.~ Aspiration input port~ 21 are disposed in the side wall of tube or lumen 12.
A~piration~input ports 21 communicate-with channel 114 and also provide access to an external source of fluid.
In this example, channel 114 would co~ n;cate with, for example, an aspirator connected to aspiration output 20.

wo s3/o~ s ~ PCr/USg2/05220 i ; ~
211~2 The internal structure in FIG. 12 shows a sleeve cap affixed to an internal sleeve 118. Sleeve 118 is bonded to the inside dis~al end of lead body 12. Headed bushing 130 is interiorly affixed to head 16 and to drive means 14 thereby permitting rapid rotation of head 16. Head 16 is prevented from precessing in this arrangemsnt.
Bushing 130 is held in place by the inside abutment surface 117 of sleeve cap 116.
FIG. 13 shows the exterior details of the device shown in FIG. 12.
FIG. 14 is a sectional view of the apparatus of FI~.
12 taken along line 14-14. FIG. 14 shows the arrangement of channel~ 112 and 114 and of aspiration input ports 21.
PIG. 16 ~ho~s a sectional view of the apparatus o~ FIG.
13 taken along line 15-15. Disposed in flats 26 are fluid output ports 46 which are, in turn, in commu~ication with header 110. Header 110 is interiorly disposed in bulb 116. Thus, liquids emitting from fluid output r-ports- 46~ create~ additional-- -turbulence. i~
conju~ction with~facets 26 80 as to enhance the overa~l thrombus dissolution performance of the apparatus.
FIG. 16 is yet 2 further embodiment of the pre~ent invention wherein fluid o~LyuL ports 46, rather than being substantially perpendicular to the axis of the apparatus, are obliquely disposed with respect thereto.

w~3ibol1g " PCjT/U~92/0522~

21~ a~s~

FIG. 16 suggests that the precise angle of fluid deli~ery from fluid output ports 46 and the axis of the apparatus is not critical. Thus, by means of a header, fluid output ports 46 could, in fact, be directed toward the catheter body (i.e., toward ~he left in FIG. 16) of the apparatus). Head 16 is mounted on headed bushing 38 which rotates against the inside abutment 117 of sleeve cap 116. In this manner, fluids are permitted to course through header 110 and out fluid output channels or parts 46. Head 16 is then turned by drive means or drive cable 14 as is clearly shown in FIG. 16.
FIGS. 17 and 18 are side views and end views of alternative turbulence generating means of the invention.
Rather than employing flats or four fa¢e~, a~ ~hown in FIGS. 10 and 11, arcuate leading surfaces 120 and obliquely angled following surfaces 122 are disposed on an impeller 124. Impeller 124, as depicted, generates a particularly advantages turbulence for thrombus di~ olution.~ Rotatio~ of the :tip- or bulbous ~head depicted in FIGS. 17 and 18 would be generally clockwise when:viewed as in FIG. 18.
FIGS. 19 and 20 depict further embodiments of this invention. Head 16 in FIG. 20 is rotated 90~ from that of FIG. 19 to show flats 26. The rounded configuration of head 26 i~ particularly suitable for withdrawing the 'WO~93/00119 ~ PCT/U~92/05220 '' 2:110~82 .

catheter from a ve6sel.
For the most part, the components for the present apparatus or as~embly will be machined ~rom a thermosetting or thermoplastic material. Tip or head components generally are made of metal, stai~le~s steel i being preferred luer adapters and related parts may compri~e a polycarbonate material. Many other sufficiently rigid, polymeric materials may be employed.

The preferred drive cable of the pr~sent invention i~ a multi-filar, double layer torque cable commercially available from Lake ~egion Manufacturing Company of Cha~ka, Minnesota. Generally, the qualifications for a drive cable ar~ that it be torquable to rotate tip or head, rapidly rotatable, and that it be of ~ufficiently narrow diameter, ~o as to permit the device to be used in ~mall ve~sels. It is, of course, important that the dri~e cable employed efficiently tra~sfer rotational torqué from~its-proximal end to the- distal.endior tip end. Efficient transfer of rotational torque means that the m~;mnm turbulence would be created adjacent the distal end or tip of-the apparatu~. Other commercially available drive cables or drive wire~ may be employed in this invention.
The inner member or inner lumen 30 of the present w093ioolig-~' PC~/U~92/05220 9 ~ 2 in~ention preferably comprises a braided polyimide tubing material 6uch as that commercially available from the HV
Technologies Company of Trenton, Georgia. The braided configuration of this preferred inner lumen material permits a very thin walled lumen to be employed which has sufficient strength and flexibility to permit pressurized fluids to be passed therethrough. The wall of the braided polyimide inner member optionally be reinforced with a braided stainless steel structure having a wall thickness of about 0.0035 inches. The optional stainless steel rei~forcement permits liquids of a higher pressure to be deployed through the inner lumen to fluid output ports, e.g., 46.
In operation, a pressurized fluid i injected or pumped from an external source through input port 18.
Passing through junction block 82 to inner lumen 30, the pressurized fluid' passes down the fluid channel 48 to exit at fluid-output port 46. Fluids emerging from output ports'46-encounter flats 26 at the base of head l6 as head 16 is-rotated via drive cable 14. In this ma~ner, a pulsatile effect is imparted to the fluids emerging from the body of the catheter. Surprisingly and u~expectédly, this pulsatile turbulence effect is believed to dramatically enhance the ability of the present apparatu~ to remove vessel obstructions such as wo 93Jo0119 Pcr3usg2/os220 2 ~.L0~
thrombi.
It is known in the art to which this invention pertains that, the de~truction products and debris of vessel or vascular occlusions or obstructions generally should not be permitted to proceed down the vascular stream. In a practice of the present invention, obstruction debris i5 prevented from proceeding downstream from the catheter by adjustment of the rates of fluid input and of fluid and debris removal.
Essentially, the rate of aspiration of fluid and debris from the site of obstruction is coordinated with the rate of fluid input so that particulate material and debris are contemporaneously removed from the obstruction sîte as they are generated. By this expedient, the downstream flow of debris generated from destruction of the occlusion is controlled.
It is contemplated that a selection of sizes of the pre~ent catheter will be employed, depending upon the si~e~of the ~esssl frQm which the occlusion is to be removed. Generally speaking, the diameter of the catheter ghould be approximately two-thirds of the diameter of the vessel in which it is to be inserted. An exemplary sized catheter, such as those depicted in the figures, i5 about 7.5 French. For coronary applications, an over-the-wire catheter, i.e., a cathet r using a guide WO''93iOOll9~' PCT/US92/0~220 9~

wire, would have a mA~;mum diameter in the range of 6F.
The apparatus of this invention is not a cutting device in the sense that mechanical cutting or shear forces are used to effect thrombus dissolution.
Generally speaking, the rotatable head will be substantially smooth. Moreover, in a preferred practice of the present invention, the device can be employed to remove a vessel obstruction with little more tha~
incidental contact between the device and the occlusion.
It is the f eature which pe~mits the present invention ~ubstantially to enhance occlusion dissolution without substantially increasing the likelihood of damaging the veRsel wall.
The above disclosure will suggest many alteratiorls and variations to one o~ ordinary skill in this art.
This disclosur~ is intended to be illustrative and not exhaustive. ~11 such variations and permutations suggested by the above disclosure ar~ to be included wi~hin-the:scope of the attached claims.~

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Claims (22)

What is claimed is as follows:

1. A catheter for removing an obstruction in a vessel of a patient, said catheter comprising:
a flexible, tubular sleeve having distal and proximal ends, said sleeve having extending substantially coaxially therethrough so as to project therefrom;
drive means, said drive means being flexible and rotatable, and having fixedly mounted on its projecting end;
head means, said head means comprising a bulbous head, said head being mounted on said drive means so as to be rotated thereby, said head means further including;
a turbulence generating means, said turbulence generating means being disposed between said distal end of said sleeve and said head so as to create turbulence when said drive means is rotated, said catheter further comprising:
means for delivering fluid proximate the distal end of said sleeve, and means for recovering fluid and debris from proximate the distal end of said sleeve.

2. A catheter according to claim 1 wherein the drive means comprises a hollow drive cable.

3. A catheter according to claim 1 wherein the head is substantially hemispherical and is hollow.

4. A catheter according to claim 1 wherein the turbulence generating means is a plurality of facets.

5. A catheter according to claim 4 wherein the head has a base on which it is mounted and the turbulence generating means comprises a plurality of facets, the planes of which are substantially parallel, the facets being located on opposite sides of the axis of the drive means, said facets being defined by the base.

6. A catheter according to claim 1 wherein the head means comprises a substantially hollow cone, the cone having therein an axially disposed stem on which the cone is interiorly mounted and by which the head means may be rotated, said turbulence generating means being mounted within said cone.

7. A catheter according to claim 6 wherein the cone is a nose cone and the turbulence generating means is a plurality of radial projections.

8. A catheter according to claim 7 wherein the projections are fins.

9. An apparatus according to claim 1 which further comprises guide means, said guide means extending substantially coaxially through the catheter.

10. An apparatus according to claim 1 wherein the means for delivering fluid comprises a lumen which is in fluid communication with the proximal end of the sleeve and a fluid delivery port located proximate the turbulence generating means.

11. An apparatus according to claim 1 wherein the fluid and debris recovery means comprises a second lumen which is in fluid communication with a fluid and debris recovery port and the proximal end of the sleeve.

12. An apparatus according to claim 1 in which the fluid delivery means comprises an inner lumen in communication with a fluid delivery port and the proximal end of the catheter and the fluid recovery means comprises an outer lumen in communication with a fluid recovery port and the proximal end of the sleeve, the inner and outer lumens being coaxial.

13. An apparatus according to claim 12 wherein the drive means, the inner lumen, and the outer lumen are all substantially coaxial for at least a substantial length of the catheter.

14. An apparatus of claim 1 which further comprises external means to provide rotational energy to the drive means.

15. An apparatus of claim 1 which further comprises external fluid input means and removal means.

16. A catheter for removing an obstruction in a vessel of a patient, said catheter comprising:

a flexible, tubular sleeve having distal and proximal ends, said sleeve having extending substantially coaxially therethrough;
a drive cable, said drive cable being flexible and rotatable, and having fixedly mounted thereon;
a bulbous head, said head having a neck and being mounted on said drive cable by said neck so as to be rotated thereby, said head including;
a plurality of facets defined by said neck, the facets being disposed between said distal end of said sleeve and said head so as to create turbulence when said drive means is rotated, said catheter further comprising:
fluid delivery ports located proximate the distal end of said sleeve, the fluid delivery ports comprising a coupled lumen and a fluid input port so that said fluid delivery port can be coupled to an external source of fluid;
fluid and debris recovery ports located proximate the distal end of said sleeve the fluid recovery port comprising a coupled lumen and a vacuum output port so that said fluid recovery port can be coupled to an external source of vacuum;
wherein said lumens, said drive cable, and said sleeve are all substantially coaxial through at least a substantial length of the catheter.

17. A catheter according to claim 16 wherein the drive cable is hollow.

18. A catheter according to claim 17 which further includes a guide means inserted within said drive cable.

19. A catheter for removing an obstruction in a body vessel comprising:
a flexible, tubular sleeve having distal and proximal ends, said sleeve extending substantially coaxially therethrough so as to project therefrom;
drive means, said drive means being flexible and rotatable, having fixedly mounted on its projecting end;
head means, said head means comprising a bulbous head, said head being mounted on said drive means so as to be rotated thereby, said head means further including:
turbulence generating means, said catheter further comprising:
means for delivering fluid proximate to the distal end of said sleeve, and means for recovering fluid and debris from proximate the proximal end of said sleeve.

20. A catheter according to claim 19 wherein the turbulence generating means is a plurality of facets on said head.

21. A catheter according to claim 19 wherein the means for delivering fluid includes ports in the head means.

22. A catheter according to claim 21 wherein the ports in the head means are defined by the turbulence generating means.