CA2045523A1 - Steerable medical device - Google Patents

Abstract

An elongate steerable implement (10, 45, 60, 76) is dislcosed, which may be either a steerable guidewire or catheter for coronary angioplasty applications. A floppy steerable tip on a steering region (16) at the distal end (14) of the implement (10) and a control device (18) at the proximal end (12) are connected by means of a plurality of axially movable deflection wires (28) extending throughout the implement. Manipulation of the control (18) permits deflection of the steering region (16) throughout a full 360·
range of motion about the axis of the implement, without axial rotation or ''torquing'' thereof.

Description

: W0 ~/0735~ 2 0 ~ ~ 5 2 3 PCT/US90~00113 ... .. .. r ., . , ~ ,~...
TEERABLæ ~EDICAL ~EVI OE
Bac~round of thç XnVentiQ~ ~
~ he present invention relates to steering devi~e ~uch as may be used with catheter~,-s~nnulAe, guidewires ~nd the like. More particularly, the pre~ent invent$on relate~ to catheters ~nd guidewir~ that ~re -steerable through body lumen or cavities and ~osit~onable with~n or ~able at obstructions, ~rgans or tisgue with~n the ~ody from a position extern~l to the body.
Medical catheters generally compri~e elongate ~ube-like me~bers which ~ay be inserted into the ~Ddy, either percutaneously or via ~ body orifice, for ~ny of ~ wide variety of diagn~stic ~nd therapeutic purposes. Such medical applications frequently reguire use o~ ~ catheter havin~ the ability to - negotiate twists ~nd turns, p~rt~cul~rly with ~egard to certain ~c~rdiov~scul~r appliQtions.
~ ne Euch Appli~at~on, ~Percut~neous '~ransluminal Coronary Angioplasty~ (balloon ~ngioplasty), requires 20 ~anipulation of a catheter from ~ position out~ide the patient'~ body through extended portions of the patient~s arterial ~yste~ to the ~tenotic ~ite ~or the purpose of alleviatin~ the obstruction ~y ~nflating a balloon. This particular procedure has ~een perfor~ed with ;~ncreasing ~5 freguency over ~he p~st year8 ~n preference to~open heart ~ypa~s surgery, whe~ poss~ble.
In a typic~l ~ngiopla~ty procedure, ~ guidewire i6 transluminally ~nserted into the ~rachial or the femoral artery, to ke positionea with~n ~he ~tenotic re~ion snd followed by a-balloon-c~theter.- ~he -c~rdiologist usu~lly pre-bends the ~istal tip ~f th~ gu~dewire-before in~ertion ~nd then rotate~ ~or t~rques) the wire once ~t has reached a ~ranch ~rtery lto ~enablé '~ e guidew~re ~o~`enter the branch. If the`angle ~f-the bend h~6-to be ~djusted, the guidewire -~ust be remo~ed,- ~e-bent and reinserted, W090/0735S PCT/US90/~
'~;,, ' ' ~ ~t~ mes several tlme~. Particular ~fficulty is encountered with prebending where an artery branches at one angle, and then ~ub-branch~s -at ~ ~ifferent angle. This procedure is attended by ~he ~i~k of significant trauma to the arterial lining~ and, ~n Eany case~, -the obstruction cannot be reached ~t all ~ith th~ guid~wire ~nd catheter.
Coronary ~rterias are-tortuous,.-hav~ many ~ub-branches and often the obstruction $s ~thQr located where the diameter of the artery ~ ~mall-or, by.its very presence, the obstruction 12aYes only ~ very ~mall open~g through which guidewire and/or cath2ter ~-can be .passed.
Consequently, the cardiologi~t often .finds it very difficult to maneuver the guidewire or catheter, -which are typically several.feet.long, from the proxi~al end.
Steering the.pre-~ent guidewire i5 further ~ompl$cated by the fact that branches ~roject -at all different radial ~ngles, thus necessitat~ng rotation of the guidewire to the appropriate degree to enter the desired ~rterial ~ranch.
However, rotation of the distal end o~ the wire.typically lag~ behind rotat~on ~Df th~ proxL~l, control:~nd, 80 that preci~e rotation~l control ~B not pos5ible. Also, ~rictaon $n the arteries can cause the di~t~l end to rot~te $n a jerky ~ashion which can ~raumatize the ~ascular ~ntima.
In Another .application, ~ransluminal; Laser Catheter Angioplasty. (la~er angioplasty)., tbe delivery.iof laser energy from ~n external ~ource to ~n $ntraluminal site to re~ove plaque or .;thrombus obstructions .~n ~essQl~ 18 ~ccomplished by pro~iding ~ v~vsguidQ ~uch ~8 ~ fiber optic hundl~ ~ithin a cathetQr.. ~h- n~tur~ ~f l~ser-angioplasty regu~re~ ~n even .great~r-~bility ~o.precisely Jnan$pulate the catheter, to control and ai~ ~h~ laser light at the spec~ic plaguas or thrombi ~o b~ ~emov~d.
A v~riety of ~ttemp~-have b~en .~ade in the pæst to pr~Yi~e catheter~ vhich-ar~ ~tser~ble ~ro~ the proxim~l end to ënabie the c~theter ~o be.~i~ed~or ~dvanced t~Nnough non-linear ~ody cc~vities.; ~;For- eYample,. ~.S. ~atent No.
4,723,936 ~to Buchbinder,~._ t al~ discloses ~ balloon ` WO ~/0735~ PCT/US90/00113 ` 20~523 .. .3 catheter, which -~6 .~aid ~o be ~t~er~ble frGm the ~roxi~al end. ~rhe catheter 16 provided-~ith ~ ~eflection wire going along the entire l~ngth ~f ~he cntheter, ~which ~ay be axially ~isplacQd to cau~e ~efl~ction at the ~i~t~l end.
However, il~he tip ~f the 4cath~ter ~an ~e ~nt in one direction only, ~nd the -~ntire c~theter ~ust be rot~ted or torqued to be guided. -:~n eddition, the design r~guires a - relatively larye ~iameter deflection ~wire, which precludes extremely thin diameter catheter~, 8uch ~5 those preferred for use for laser or ~ on angiopla~ty spplication~.
~ .S. Pat. No. 3,470,876 to ~rchilon ~iscloses a catheter dev~ce :~aving ~ -(central lu~en extending ~herethrough, ~nd four tensioning cordR ~xtending ~iong ~n inner wall ~f ~he ~theter. ~he ~876 patent ~pecifically recites that catheter~ ~ay::be prcduced ~n accord~nce with the Barchilon de~ign having diameter~ ~f .125 to 2 inches, ~nd are suited for ~pplic~tions ~uch as wit~in the duodenal bulb or ~s~ending ~olon.~'~hese din~eter6 ~re ~nsuited for u~e as ~ guidewire ~n coron~ry ~ngiopl~ty, whi~h typically reguires diameter6 ~n the are~ -of a~ s ~rom ~bout 0.014 to 0.018 inches.
In the context o~ ~oronary:-~ngiopl~sty ~pplic~tions, the prior ~rt ~enerally ~uffer~ from ~i~advantages ~uch AS
limited steerability --~nd excessiYe -external - aiameters.
Li~ited catheter tip ~teer~bility result~ in greater time 6pent in the body ~nd ~ignif$cantly elevated ri~k of trauma both to the ~ascular intima ~nd to tbe patient ~n gener~l.
Multiple in~ertions o~ guidewir~s or catheter~ ~ay l~d to thro~bosi~, a~ a rssult -of coagulation co~menc~ng along a ~uidewire ~surface. -- Add~tion~lly, ~r~c~se ~rection~l c~ntrol in ~a~er ~ngiopl~ty -~ of the utmo~t importance to assure accuratQ -ai~ing ~ the -laBer 9bea~ to ablate the ~ttendant plaguQ.:i~Howe~r;~he only ~prior art catheters h~v~ng ~ulti-dir~ctional ~teerabl~$ty are typ$c~11y greatly in excess of practical ~ngiopl~sty cath~ter~iameter5.
, . In addition to llmited ~teer~bllity,;~the prior ~rt -- guidewire~, *Buch ~ Shose ~ losed-~y Buchbinder ~nd $n WO90/073S~ ~ 4S~ PCT/US~/~01~ ' A i ., _f _ - 4-U.S. Patent No. 4~719~924 .-tO Crittenden,- rely-;~pon the spring tension o~ the,.,guidewire coil .~and the resilience of the distal. ~nd of the ~eflection ~ire, in the -case of Buchbinder) to return th~ guidewire to the ~tra~ght, unbent position. ~owever, as ~portant a~ de~lecting the wire to enter a branch ~rtery i8 ~traightening the wire after the branch i6 n~gotiated. ,, Any -~bility to-~traighten ln the prior rt devices ~escribed aboYe results ~rom the spring tension or other ~tructure in the digtal end of the wire, ~hich ~tructures .~l~o compro~ise the des$red floppiness of the guidewire tip.
Thus, there - re~ains n need for a ~mall ~iameter steering davic~, which ~ay be readily adapt~d for use in the construction -of 4ither .guidewires or ca~heters, and which i~ especially suited for procedures ~uch~s balloon or lAser angiopla~ty.--:Preferably, the steering device is constructed in a ~anner which per~its ~ ~iameter a~ small that of exi~ting dilatation catheters or guidewire used in angioplasty applications, ~,yet, i~ capable o~ complete deflective ~ovement, throug~out a full 360- sAnge Or ~otion, without axi~l rotation. ,~
- Summary,,Q.~_the InventiQ~ ~: ~ ' .In. accordance ~it~ one ,~8pect ~of ~the '~resent invention, there i8 ~rov$ded.-,~n. .~proved teerable 2S guidewire or c~theter; ~mpl~ment -o~ the typa useful ~or percutaneou~ tran~lu~inal --lnsertion ^lnto t~e coronary va~cular ~y~te~. .,~. ~h~ .~n~ention.. ~er~its ~controlled negotiation ~f branche~, ~nd turns ~o guide a~ angioplasty catheter or ~u~dew$r- to-an ~rteriAl ~teno~is' ~r le~ion or other treatment ~ite,~ithout the,nsed ~or -prebending or torguing of th~ $nstru~Qnt.2. Ih- d~stal .t~p on ~t~erable imple~ents ~e ~ .~ccordanc~ h tbs.present ~nvention can ~e contr~llably radially ~i5placed..in any-~irect~o~, thus per~tt~ng a .fu11 ~60-- r~nge^~f ~otion without the need to rota~e..the body of the ~teerablQ l~plement~ c In ,one .~mbodl~ent ;~DP~*h~:: present sinvention~ a , guidewire ~s ~rovided:-~a~ing ~an ~longate ,flexible ~haft ... . .

WO ~0/073~ PCT/US90/00l13 _5_ wit~ a centr~l ~u~en -extenaing ~herethrough ~and ~ floppy -resilient ~lp ~n the -di6tal ~nd. -~n ~xially extending ~teering post i~ posed within ~ ~te~ring region on the distal portion of the 1ex~b1e ~haft. ~e ~t~ering post is pivot~bly ~ecured at $ts proxi~l nd ~o a radi l ~upport -- axially secured within the flexible ~haft ~t the proxi~al end of the steering region, to prevent axial ~i~placement of the stearing post while ~t the ~ame time lper~itting l~ter~i deflection of ~he cteering post out of parallel with the axi~ of the flexible shaft.
At least one ~nd prefer~bly four deflection wires are ~xially mov~bly disposed within the lumen of the flexible ~h~ft, ~nd extend ~roxi~ally~ from -a distal ~point of attachment on the st~ering post throughout the length of the flexible ~haft -~o -a control at the proximal end thereof. Each deflection wire pas~es through a notch or orifice on the radial ~upport. - ~
In ~nother e~bodi~ent, the ~teering post is provided with a wire ~nchor r2~ion at it~ ~istal end ~nd a wire guide region ~t ~ts proximal end. ~referably, the cross-~ectional area of the ~08t ~t A point intermediate theanchor reg~on ~nd guide regio~ is less than the cross-~ectional are~ of the post at at le~st one of ~he anchor region ~nd guide re~ion, and, more preferably, i6 legs than the cross-sectional area of the post ~t ~oth the guide region ~nd anchor ~Qgion. -: ~
In ~ further ~bodiment, ~ ~eflect~on ~ir~ anchor ig disposed in the ~teering region o~ the ~lexl~le ~h~ft, ~paced apart in ~ ai~tal direct~on ~ro~ a de~l~ction wire quide. Preferably, opposing pa~rs of ~eflect~on wires are formed ~y provi~ing ~ continu~us length o~ wire which 1OGPS
at ~ts midpoint acro~ ~he aistal and of the ~nchor, hoth ends exten~ng~through the ~lex~le ~haft in ~ proxi~al dire~tion. ~ t~
- ~xial ~ovement o~ ~ny ~ne of ~ e ~e~lection~w~res in a proxi~al direction displaces the ~xi~ of the steering post -~n a unigue lateral direction, ~nd ~hrough co~binationc of WO 90~0735~ PCT~US90/~113~
23 . -6-, ,, ~ ., i ~` ;proximal axial displacement of -~ore Shan two deflection wires, the ~teering post i~ c~used to deflect laterally and rotate throughout ~ ~u11.360- ~nga of-~otion ~bout the axis of the flexible ~haft. , -. ;. ^. :.: .
The 6teerab1e medic~l ~evice of the present lnvention can thus negotiate tortuou~ and branched arter~al ~yste~s, ~ithout the need for ~ithdrawal and ~ultiple insertions to deflect th~ tip, or ~xi~l rotation of the c~theter body.
The ~teerable ~edical device ~an ~e readily-manufactured in accordancs ~ith known techni~ue~, ~nd ~t a low per unit cost.
- Theæe and other features and advantages of ~he present invention will beco~e ~pparent -from the-`-detailed description o preferred embodi~ent~ ~which ~follows, when considered together ~ith the ~tt~ched drawings nnd claims.
. Br~ef Description of the D~aw~gs ~:
Figure 1 is a parti~l sectional per pectiv~ view of 6teerabl- guidewirQ ~ccording to .the -present- in~ention, with the outer tubular caRinq removed. . ~ , -F$gure 2 i~ an el~vation~l ~ectional ~iew of the guidewire of Figure 1, illustrated ~n ~ ~irst deflected position.
Figure 3 i~ an elev~tional sectional ~i~w of the guidewire o~ Figure 1, illu~tr~ted in a second deflected position. ~ , - . 3.'~
Pigure 4 i~ a parti~l ~ection~l per~pective :view of a steer~le laser ~ngioplasty ~thet~r ~ccording to the present in~ention.
Figure 5 i8 ~ ~urther a~bodi~ent o~ the ~teerable guidewire o~ th~ prese~t in~ention. ...
Figure 6 i~ a 5che~atic ~i~w o~ .~ha,guidewire of Figur- 1, lllustrated a~ n~gotiating ~n ~rterial ~ranch point ~n~ approaching ~n-~rterial steno~
Figure 7 is an ~l~vational per~peotive :~iew -of a further e~bodiment o~ 5~, ~teering device.nccording to thë
present im ention~ 2~ ' r ~ L ~

WO ~/0735~ PCT/US90/00113 - , 204552~
Figure.8 ~ an ~levational per~pective ~$ew of st~ll a further embodim~nt of the present ~nv~ntion.`~ L
~igure 9.1~-a cross-s~ction~l view ~lo~g the line 9-9 of the device of Figure 8. ~
~igure 10 i~ a ~implif~ed Sront elevntional ~iew of the device 6hown -in ~igure ~ llowing appl~cation of an anc~ur cap. ~ --~igure 11 1~ a ~implified front -~levat~onal ~iew of the device ~hown in ~igure 7, following applicat~on of an anchor cap.
DetailQd Pescription of Preferred ~bodimen~
Referring to Figure 1, there i~ elo~ed an elongate flexible implement 10, ha~ing ~ tubular body 11 with a proximal end 12 and ~ dist21 end 14. ~The ~i~tal end 14 compri~es ~ Eteering region ~6, ~nd the proxi~al end 12 is provided with ~ control 18 for ~teering the i~plement 10, w~ich may ~e, ;for -exa~ple, ~ steera~le guidewire or catheter. Although the ~teering ~evice o~ the present invention ~ill ~qener~lly - ~e -described ~~erein a~
~ncorporated into ~n angioplasty guidewire, it ~ to be under6tood that one ~killed -in the art will be able to readily hdapt the steering device-to other ~edical ~nd non-medical ~ppl~cations. : - ^~J -`' - ' ' -'' The bcdy ~ Df steerable implement ~lO ~ay be any desired length fro~ inche6 to ~any ~eet ~epending upon the intended applicat~on. In ~n ~bodiment u~e~ul ~s ~n a~g~oplasty guidewire ~r cathet~r,- the ~ody ll will typically ~e ~everal-~feet -lo~y, ~Lnd w~ll prefer~bly be about 180. c~ 8 ~typical --~f ~xi~t~ng angiopl~ty catheter6. Ho~a~r, ~ny ~uitable lengt~ ~ay be used.
~ h~ ~ody 11 ~y ~æ ~on8tructed ~n any o~ a ~ariety of ways known in the-~rt,'~uch ~s ~y tlghtly~winding ~ ~oil of retal ~ire, ior extru~o~ of a r relati~ly flexible bioco~pAt~ble poly~r sUch a~ --polyethylene. ~ound guidewires preferably co~pr~e a ~gh ~ten~lle ~treng~h wire of ~ resili~nt, non-corro~ive ~etai sUCh as ~ta~nless ~eel or platinum, and may ha~e a circular cro~s-~ection with a W090/073~ PCT/US~/~011 . -8-di~meter of ~rom-.~bout ,~.001 to ~.020 ~n.- The wire may alternatively ~hhV~ a -rectangul~r -cross-~ection :of from about 0.001 to 0.020 inches by from ~bout 0.001 to 0.040 inches, or other variations known in the ~rt.;: Construction ~aterials and t~chniqu~s ~or ~anufacturing wire wound guidewires are well known ~n the art, ~nd a typical 180 cm teflon coated 0.014 lnch or 0.016 inch diameter non-steerablo guidewire ~ay be obtained fro~ ~.S. C~theter, Inc., ~ di~i~ion of R. Bard, -Inc., located in Billeriea, Massachusett~, U.S.A.
The external diameter of ~ire wound guidewires will of course be a function of ~he intended Applic~tion. The wire wound coronary angioplasty guidewires ~ncorporating the ~teering device of. ~he ~resent :~nvent$on- are preferably wound to have ~n extern 1 ~amQter..in the ~range -of from ~bout 0.014 inches to ~bout 0.018 inches. In steerable catheter applications, the dia~eter of the c~theter:can be varied to opti~ize the di~meter o~ :~ centr~l working cbannel as de~ired, while ~till ~aintaining ~ ~ufficiently ~mall exterior diameter- ~or the -intended ~ application.
Steerablo balloon angioplasty catheter~ incorpor~ting the present invention will typically h~ve ~n exterior ~ia~eter in the range of from ~bout 0.020;:inches -to ~bout 0.041 inches or larger as per~itted.~y location.o~ the lesion.
Preferably,. ~ e -exterior Burface ~f the ~o~nd coil type guide~ire ~sha~t 10 - i8 proYid~d with an -~la~tic, bioco~patibl~ coating or~oath -to pro~ide-~ g~ooth outer ~urfac~. Suitabl- coatings ~can ~e ~or~ed ~y A~ipping, ~praying o~ wrapp~ng ~nd hoat-curing operation~ a8 are known in_th~ Alternatively,~-he~t-i~hrinkabl~ ~ubing ~an provid~ uita~l~ outQr ~b~a~h.-~ A coatlng ~terial should be ~el~cted which w~ll;pernlt ~uftici~nt ~lexing of the ~ody ~ ~ithOut crack~ng~ will ~in~ liding friction of the $~plement 10 dur~ng -in~ertion an~ removal, and i~ ~ubstanti~lly ~hem~lly ~nert-~n.~th~ -iin vi~o ~ascular enYironment. ~ variety-~f-~uitabl~ D~terials are -- c. .. .. . . . . .
r '-~. -c`-_ --8!LrJ2'..~ ~ 9Y5.' V,~ k. s ~s,,lJs!--, ~.

WO90/073~5 PCT/U~90/00113 2n~5~
_ _9_ .
known, ~ncluding, ~or ~xa~ple, polytetr~fluorobthylene, urethane or polyethylene.
The body ll of -fl~xible -i~ple~ent ~0 typically terminates ~t -~t~ -.~istal ~nd 14 ~in n -closed tip 20.
Numerous guidewire ~nd catheter tip construct~ons ~re known in the ~rt and ~ed ~ot be detailed ~xt~n~ively herein. In general, the ~ip 20 ~ --preferably a rounded closure constructed of ~ res~lient ~olymeric ~ateri~l ~uch ~s silicone or ureth~ne whi~h -will ~in~ize trau~a to the ~as~ular intim~ w~ e ~ppreciated by one of ~kill $n the ~rt. As ~ ~afety feature, to facilitate co~plete remov~l o~ frag~ents of ~ broken guidew~re, a ~afety wire ~ay ~e 6ecured at one end ~o ~he ~n ~de of the tip 20, and at the other end to the post:22 or ~upport 24.
Disposed ~ntermediate ~the tip 20 ~nd ~ody -11 of ~lexible implement 10 ~n ~ccordance - Yith the present invention is a floppy but oontroll~ble ~teering region 16.
Steering region ~6 -~s constructed ~n -~ ~anner th~t facilit~tes later~l displace~ent o~ the tip 20 rel~tive to the ~xi~ of the body 11, through phy~ic~l ~esign ~nd/or choice of fl~xible ~onstruction ~aterial6.
For example, ln ~ ~yp~cal-angioplasty ~uid~wlre or cathete~, where~the flexible ~ody 11 c~Dpr~ses ~ ~ethl wire . coil, the revolution~ ~f wire per unit o~ ~xi~ istance 2S along ~he body i~ reducQd ~n ~hei ~teering region 16 relative to ~cdy ~1 to provide a loo~er wound coil having ~pace 17 between adjacent wire-~oop~, as illustrated ~n ~igures 1-6. . ~hus, ~QfQrri~g to'~igure 2, ~t can be ~een that lateral deflect~on o~ ~eering r~gion 16-~o the left ~ay involve both ~n ~x~al compre~ion of ad~acent wire loops on ~he lQ~ide ~Nrface 36 ~f the ~end, an~ an axial ~eparation ~f -khe ad~cent -~ire ~OOp8 ~n~ t~e outside surface 38 of the ~end. ~ ~~
. - ~Altern~ti~e ~esignfi ~or~-~ateri~18 ican~ ~e e~ployed, provided that the cath~ter exhibit~ Eufficient~ lateral flexibility. In ~eneralj; the steerin~ s~gion ~16 ~ay ~e -~ade from ~ ~ariety of ~uitable-~etal or plastic 00~16 or . . .

WO 90/0735~; PC~/US90/~011a 204~23 . . ~
flexible sleeves. katerials opaqu~ ~to ~-r~ys, -~uch as platinu2, gold, tungsten, tantalum: ~r ~he like, ~ay be ~dvantageouEly - ~ncorporated therein, to act as a fluoroscopic marker to A~d ~n precise positioning of a ~alloon saction of ~h~ c~theter._- -In ~ccordanc~ ~ith the ~teering ~echan~sm of thepresent ~n~ention, a at~ering po~t 22 i~ prc~ided, extending ~n ~ senQr~lly ~xial directlon within the steering re~ion 16 o~ flQxible body ~1. ~raferably, the steering post 22 i~ diEposed coaxially within the central lu~en of ~teering region 16 when the ~teering region 16 and ~ody 11 are linearly ~ligned, ~uch a~ when at -rest. See Figure 1. As will be descri~ed, the steering post 22 is secured in *he ~teering - region ;16- in -a -~anner that substantially prevents -~xial di~placement thereof yet perm$ts lateral deflection of the ~xi8 of the ~teering post 22 away from the axi~ of body l~
~ ost 22 preferably compri~es a resilient ~haft which may ~e mold~d or ~xtruded fro~ any o~ a -v~riety of 20 ~ateri~lfi~ 8uCh a~ nyl~n, ~nd ~y haY~ a cross-section~l d~ension o~ ~rom ~bout-~.002 ~nçhe~ -up ~o about 0.012 incheo for us~ ~n ~ typ~cal steer~ble ~ngioplasty gu~dewire embod~ment. -AlternatiYely, a ~riety: ~f resilient or ~pringy metalfi in the for~ of wira can also be used to form ~ost 22, ~uch ~s pho~phor bronzo or other res~ nt metai~
In general, ~t ~ desirabl~ to elect ~ ~aterihl which w~ll perm~t some degr~ Or bending and roturn to it~ or~ginal shape, and will re~$~t aY~l compre~on under-th~ ~orces typ~cally AppliQd ~n -the ~ntanded ~e o~ the ~teerable imple~ent 10. ~ L~o The l~ngth o~ ~teer$ng-po8t -22 ~~ll,^ o~cour~e, be dependant upon the length ~f the ~teer~ng region ~6. -In a typical ~teerable guidQwire for ~ngiopl~sty~-~ppl~cations, the entir- ~t~er~ng~region-l6 ~lll be on the-order of fro~
~bout .040 to about l.0 ~nche~ ~nd pre~2rably -fro~ nbout .120 to about FlS0 -inch~ long,~and ~he ~teering pogt 22 may ~e ~ from on~-qu~rter ~to--two-thirdu ~hat 'lengt~.

w,o so/0?3s~ PCr/US90/00113 204~23 Although 6teering pc~t 22 ~ay ~xtend dist~lly all the way to the distal tip 20 of ~ e ~teerabl~ impl~ment 10, it i5 preferred to limit the l~ngth ~o .the proximal one-half or one-third of the ~xial length ~;of ~teering r~gion 16 to minimize rigidity ~n the ~teering r~gion 16 yet permit sufficient ~teerabllity ~her~of. : .
For example, ~n a typic~l ~ngiopl~sty guidewire the distal end 27 of ~teering po~t 22 ~11 be ~paced apart from the ~nterior ~urface of tip 20 by ~ d$st~n~e of Sro~ ~bout one-tenth to one-half an inch or ~ore, 1~hus permitt~ng the gteering region 16 of the ~atheter ~hflft to be a~ ~loppy as desired. HoweYer, ~n .~n -~mhodiment where the -di~tal por~ion of a fiber optic~ bundle or flexible tube for definin~ ~ working channel -~dditionally functions ~s the ~teering post 22, the po~t 22-will ~xtend all the way to t~e distal tip 20 and be exposed to ~he outside by way of an opening therethrough. See, for example, ~$gure ~.
In ~ p~rticularly preferred embod~ment,;stQering post 22 is further provided with ~ ~e~a or enlarged region 26 to optimize tr~nsmigsion of lnteral force from ~he ~teering post 22 to the wall of ~teering r~g$on 16. For thi~
purpose, bead 26 i~ mo~t effectively .located ~t or near the di~tal end of ~teering post 22. ~3~ad 26 ~ay be ~or~ed by dipping or ~oating techn~ques,.or ~y ~e ~ preformed member having an opening therein for sliding over the ~nd of ~teering post 22. _~lternatively,:~o~t 22 can be ~olded or milled to provide a bead 26 .~ntegrally ~oroed thereon.
Bead 26 i5 preferably ~ubstantially ~ircul~r ~n ~ ~ross-~ection perpendicul~r. to the ~xi~ of po~t 22, ~nd the external di~meter of the kead 26 ~ only ~l~ghtly l~ss than the ~terior din~eter -~f *he ~teering region 16 ~o that maximu~ lateral ~otion ~of the :8tQ~ring po5t 22 i~
transmitt~d.~o the steer~ng r~g~on :a6,^ but~~eaa ~6 also remain~ only ~n slidablQ contact ~itb thQ :lnter~or ~urface ~hereo~
The proxlmal end 23 of the steering post 22 ~ ~ounted to or ~n pivotable contact w~th n radia~ ~upport -Z4, in WO90/0~3S5 PCT~US9Ot~ll--` 20~5~23 ~ 12-~anner which .permits pivot~ng- ~f the steering post 22 throughout a u11-~60- ~ange -of ~otion about the 8XiS 0~
body ~1. ~he post ~ay 'aleo be ~olded or ~illed as an integral part of ~isk ~4.- The ~upport ~4 comprises any means by which th~ ~eflection -wire~ 28 are displaced radi~lly outwardly fro~ th~ nYi8 of the tubular body 11, relative to their point o~ attachment to the steering post 22, as will be discussed. c- ~--Referring to FigurQ 1, the support 24 o~ the illustrated embodiment comprises a circular disk 25 locatedwithin the *ubul~r body 11 of thR ~teerable ~mple~ent 10, preferably lo~ated near the di~tal ~nd thereof. ~he disk 25 i8 axially secur~d within the tubular body 11 to provide a stationary radi~l ~upport ~or at least one deflection wire 28, and pivotable mount for steering post 22. Disk 25 may be attached, -for example, by friction ~it between nd;acent turn~ o~ coilad spring w~ré; - Steering post 22 prefQrably i~ attach~d -to or in contact w~th the di~k 25 ~n a manner wh$ch per~it~ ~t to swivel from 90 degsees to clo e to .0 degree~, r~l~t~ve to the l~teral plane o~ disk 25. . . . . ~
~ he d~k 25 ~ay be ~ade of ~tai~less steel or any of a variety o~ other suitabl~ ~aterials such a~ other ~etals or plastic poly~ers w~ich ~ill provide a sufficiently axially rigid seat ~or the proximal ~nd 23 of steering post 22.
Dis~ 25 ~ay be ~ormed ~y -8ta~ping ~ro~ sheet stock and dr$11ing, ~n~ction ~olding,:or other technigues ~ell known in the ~rt. Pr~fer~bly,` ~ central depression or or~fice i8 pro~ided ther~on, ~or pro~i~ing an;~xi~l ~eat ~or steering po~t 22. ~ qhe di~eter ~o~-~$~ 25 c~n ~ary, ~owever, it will typically b~ no greater than, but may ~pproxi~te the outside diameter.~of th~ ~teerabl~-~ple~ent 10.- Diameters from sbout D.14 ~to ~.~5~ ~nche~ ~y prefer~bly ~e used $n the constructi~n Or car~i~c angi~plasty catheters.
Lateral deflection o~ the ~teering post 22 ~way from .-the -~xi~ Df body~elZ i~ ;acco~pl~shed5by proxl~l ~xial . displace~ent of.~ny of-~ rplurallty o~ ~eflection wires 28 WO 9o/07355 P~/US90/0~1 13 _ -13- `- 20~5S23 extending proximally~throughout ~the lQngth-of ~lexible ~ody 11. Although ~nly a eingle defl~et~on 4wire-~8 or two deflection wires can -be ;u~ed, pr~f~r~bly thr~e or ~our deflection ~ires 28 are ~ ployed ~o-~rov$de ~ ~ull 360-r~nge of ~otion of the ~t~ering rQgion 16 ~bout the ~xis ofthe ~ody 11, ac w$11 ~ecome ~pp rent. ~Only ~ ~ingle deflection wire 28 ~ill ~e descr~ed ~n ~etail herein.
The di~tal ~nd of ~eflection Yire ~8 i~ ~ecured such hS by adhes$ves to the steering post 22 ~t ~he distal end thereof, or ~t a variety of .other l~cations ~lon~ the length of post 22. Iypically, ~ecuring deflection ~ire 28 closer to the proxim~l 4nd 23 of po~t 22-w~ll maxim$ze the lateral force ~o~ponent generated by axial displacement of the deflection wire 28,-~nd ~or th~t rea~on, deflection wire 28 is preferably ~ecured *o post 22 ;w$thin the proximal half or one-third of the axi~l length ~f the post 22 ~xtendlng ~i~t~lly of ~upport ~4O LBy ~ttached" or "~ecuredn to the po~t and ~ lar language herein, lt is to be under~tood th~t the ~efl~ction wire 28 ~ust ~e ~echanically linked to the ~o~t 22 but ~ed not necessarily be directly secured -ther~to. - ~or example,-the ~eflection wire 28 could ~e 6ecured to ;~n annul~r ~l~nge or ring ~urrounding the post or -other -~tructure ~hich ~ay be convenient from ~ ~anufacturing ~tandpoint to ~ruvide a sufficiently ~ecure link~ge ~to .~cco~pl$~h the -intended ~teering function. i~lternati~ely, an ~ye on ~h~ end of the deflection wire can ~urround the po~t 22 and rest ~gainst a ~top for~ed ~y ~ ed shOUlder ~r-adhesive, or other Deans of att~ch~ent ~ w$11 ~e apparent to one of ~kill in 30 the art. ;; ~ - - r F - ~
~ he defl~ction ~ir~ 28 . pref~r~bly - ~xtena~ rad~ ally outwardly ~rom the point of atta~hm~nt ~o the ~teer~ng post ~2 to the ~upport 24. ~ F~r t~i~ purpose,- the ~upport-24 $s prefer~bly provided with ~ notc~ or ~rifice 40 for each deflection ~ir~ 28 ~o ~Ytend :~hrough, ~a~d~orif$ce 40 ~p~ced radi~lly outw~rdly-from the ~X~8 of the tu~ul~r body 11 by a ir~t di8t~nce. ~rhe dist~l end of ~ach deflection WO90/0735~ PCT/US90/00~-``~` 204~23 - . -14-wire 28 i8 ~ecured -~o ~he -~teering post 22 at a point radially displaced`from the ~XiB 0~ tha steering post 22 by a sQcond di~t~nce, ~nd ~e ~irst di~tance i5 preferably greater than the seeond distance to ~axi~ize the lateral co~ponent of force. ~ e ~econd di~tance preferably approaches zero; ~owever,-~t will $nherently include the radius o~ th~ ~teering po~t 22 w~erQ th~ deflection wire 28 ~8 secured intermediat~ the ~wo Qnds thereof.
In the ~ost pre~erred e~bodi~ent of the present invention, ~our de~lection wires 28 are provided, e~ch passing through an ori~ic~ 40 in ~upport 24 ~paced at angles of approximately 90- ~part from each other along the plane of the support-24. In a three deflection wire embodi~ent,.as illustrated in Figure 1, each orifice 40 is separated fro~ each ~d~acent orifice by an angle of approximately 120~
The deflection wireE ~ay bo ~ade of ~t~inless steel, nylon or any other suitable ~ateri~l which provides su~icient tensile trength ~nd ~lexibility. The diameter o~ the lines can range ~ro~ ~.001 to -0.005 in~hes or more, and 6uitability o~ particular ~i~es or ~terials can be readily determined by experi~ent~tion.
~ control device 18 for ~t~ering t~e catheter is ~hown ~che~atically in .Figures 1-3. ~he control device 18 is preferably provided.~t ~ts center ~ith a pivotable mount 32 to permit it to be tipped throughoutia ~ul~ 360- range of ~otion. In th~ illu~trated e~bodi~ent, control 18 compri~es a circular plato 34 ~ecured to proxi~al end 12 of ~lQxibl- Eh~ft 10 ~y w~y o~ plvotabl~ ~ount 32. Deflection w~re~ 28 aro ~paced ~gually radi~lly outwardly from the pivotable center o~ thQ control devic~-and at equal angular dist~nce~ ~round the plat~ 34. De~lecting plate 34 from a plan~ normal to .the ~xi~ of :~h~ft ~0 tr~ns~ts forc~ vi~
one or more dQflection wire8 28,~ a ~omponent ~f -which i5 resolved ~nto a lateral ~orce to deflect the catheter tip toward or away ;fro~- th~ ;~ongitudinal ~xi~ o~ -c~theter.
Selective ~ipping of -the qd~fl~ction~ platë ~4 ~result~ in ^ W0 ~/07355 PCT/US90/OOlt3 ; -15- 2oq~s~
rotation of the catheter tip to any desired orient~tion.
A variety ~f ~lternative -~ontrol ~de~icQs ~an ~e envisioned Sor use with the ~teerable ~mplement-of the present ~nvention. For ~x~mple,-~ ~joy ~tick" type device s comprising ~ ~ingle lever whic~ can be di~pl~ced to any posit$on throughout a nearly hemi6pherical r~nge ~f motion might be used. As ~ fur~her alternati~e, ~ portion of the proximal end 12 of ~ubul~r ~ody 11 i~ ~nlarged to a cross ~ ection of ~ half inch or larger to facilitate gr$p. The enlarged 6ection ~8 provided ~ith ~ plurAlity o~ ~xially ~lidable ~witches, one correcponding to ~ach deflection wire 2~. Manipulation o~ the 6witches iby ~he thumb or forefinger will obtain the desired deflection of steering region 16. As will be appreciated ~y one of ~ n the art, ~ny control de~ice will prefera~ly ~e pro~ded with ~
stop to prevent bending of ~he post 22 or ~t~er~ng resion 16 past its el~stic l~mit.
A ~ariety of factor~ impact the a~ount of ~he lateral force component exerted on ~teering po~t ~2 by ~xi~
proximal di~placement of ~ny of deflect~on wires ~8. For example, ~ orifice ~0 i6 ~oved further ln ~ radially outward direct$on, the l~ter~l ~orce ~o~ponent will $ncrease. Iateral displacement of-orifice 0, ~owev~r, ~s constrained by the maximu~ -dia~eter that the ~teer~ble implement c~n have for ~n i~tended ~ppl$cationO
Alternatively, ~hortening the ~xi~l-distance ~rom the support 24 to the point of ~ttach~ent 42 ~f tbe deflect$on wire 28 to the ~teering po~t 22 increases the nngle ~etween the ~xi~ of po~t .22 and 4eflection Y~re 28, thereby $ncreAsing the lateral ~omponent of force. -- For this reason, ~upport 24 i~ ~ypic~lly w$t~in-sne ~r two inche~, ~nd pr~fernbly le~ ~han one ~nc~, ~rom tha a$~tal tip 20 of an angio~lasty catheter -or:gu$dewire ~bodi~ent lof the invention. ~ c. .~ ; 3~
A further alternatiYe i6 illu~trat~d $n ~igure ~5~ In thi~ embodiment, ,~ fulcrum 44 i~ prov$ded ~t -a point intermedi~te the r~di~l 8upport 24 and p~int of atta~hment WO ~/0735~ , PCT/USgO/~1i 2~4~5~ -. 42 for ~aintaining ~he:deflection ~ire 28 concave in a radial $nward direction. ~he fulcrum -i4 ~ay conveniently comprise a substantially r~dially sy~etrical member ~uch aQ ~ sphere or toroid, -which c~n also`~unct~on to limit S proximal axial ~ovement of ~te~ring post Z2 through a centr~l opening in support 24. ~n thi6 Qmbodiment, the point of attachment o~ deflection wires 28 m~y be to the fulcrum ~4 ~nstead of dlrectly to the steering post 22.
In accordanc~ with ~ further ~spect of the present invention, there ~ 8 pr~Yided ~teerable ~edical implement for use in percutaneous tr~nslu~inal laser angioplasty applications. Referring to Figure 4, there i~ d~closed an elongate -~lexible i~plement 45 comprising ~t ~ts distal end ~ floppy ~teering region 46. As described with previcus em~odi~ents, ~nh~nced flexibllity may ~e imparted to ~teerin~ region 46 by provid$ng ~pacing 47 between ad~acent loops of wound wir~ 48. - -A ~di~l ~upport ~eans 49 i~ dispo~ed at the proxi~alend of st~er~ng region 46, wh~h ~hy comprise a c$rcul~r -20 plate 50 or other ~tructure for ~i~plac~ng deflect$on wires - 52 radially outwardly from the axis o~ i~plement 45.
A w~veguide-~uch as ~ ~iber ~ptic bundle~54 extends ~hQ entir~ length of the ~plement 45, for directing laser light fro~. a source -tnot illustrated) disposed at the proximal end ~f-the i~plement 45, to a point of application with~ ~ coron~ rtery et - t~e disthi tip 56 of the irpl~ent 45. For:-~his -purpose, the optical pathway 54 extQnds throughout th~ lQngth o~ stQering r~gion ~6 ~nd travQrses tip 56 by way-~f ~n opening 58 therein.
~ach of the defl~ction ~ire3 52 ls secursd at its ~i~t~l ~nd to ~he -Siber -optic bundlè ~4 at ~ point - ~ nter~edi~te ~rad~al `--upport ~9 -~nd `distal tip 56.
Preferably~A~s ha~ en pr~iously de~cribe~, the po~nt of ~tt~chment of deflection wires 52 to the ~iber optic bundle 54 ~ ss-th~n ~al~ the-distance ~ni-preferably 1~ within one-third of th~ distance ~etween t~e ra~ial ~upport 49 and W0 90t07355 PC~ 00113 20~523 ~ 17- ~
di6tal ~tip 56, in Qr~er to optimize the l~ter~l ~omponent of force.
Thus, ~tilizing - ~ control .~evice ~s ~revisusly described, a l~ser angioplasty ~c~theter incorpor~ting the S present invention ~er~it~ the ~ontrolled ~irection of a beam of light tran~tted ~hrough -~ber ~undle 54 ~t any desired point ~ithin a full 360~ c~rcle on ~ pl~ne normal to the axi~ of the imple~ent ~5. :-As is well ~nown in ~he f~ber ~ptic$-art, nu~erous functions ~an be ~ccompllshed ~hrough a waveguide 6uch ~s fiber bundle 54. For example, ~ub~t~ntially par211el but discrete ~undles of fiber optics can ~e ~ecured adjacent one another within ~he fiber ~ibundle 54 ~o permit a plurality of discrete light transmitting -~hannels.
Alternatively, ~ plurality of concentric optic~l p~thways can be provided as is well ~nown in the ~rt.- : -A plurality of -diacrete ~ptical pathways may advantageously ~e used to perform ~ 3variety -of functions.
For example, a first optical ~athway ~ight ~e utilized to permit visu~lization of the ~tenotic site or ~ther -oeurfaoe to be treated. A ~eparate optical pathway aay ~e utilized to transmit light for -illu~inating ~he ~ite. ~et a third optical pathway m~5ht ~e -utilized to tran~it the laser light. These and o~her a~pects :of zthe -~iber ~ptics ~nd laser light ~ource are well ~o~n to those e~illed in the fiber optics nrt.
A variety ~f additional functio~6 ~ay -be performed through use ~f ~he ~dditional ~nterior -s~ace -v~thin the housing of ~teerable ~ple~ent-~5~ or ~xa~ple, --in a preferred embodi~ent, ~n ~piration duct ~y ~e provided near the di~t~l end of ~the ~mpl~ment 4~,~for ~uctioning debr$ or gases which-~ay ~ generated ~as a result of the action of ~ the laser. ~ _~lternativ~y,~- ~n ~ lace o~ ~
waveguide S4, a ~lexible tu~e ~a~y ~e ~incorpor~ted ~nto the ~teering device of the pre~ent I~Yention, thereby prov~ding working _c~annel ~to ~eceive s~ t~n~l -$~plement~
therethrough.

WO90/07355 PC~/US90/0011~
:`;; 20~523 ~ 18-Re~errinq to ~igure 7, there i8 di closed -a ~urther embodiment of the Gteerinq device in accordance w$th the present invention. c~rh~ steerabl~ de~ice ~tllugtrated in Figure 7 can be incorporated ~nto ~-guidewire,-Dr directly into a catheter, such ~ a balloon ~ilation catheter, or other elong~te ~mplement for which ~teerabil~ty ~8 desired.
~t ~ to ~e under~tood -that whll~ ~ertain preferred dimensions and construction -~aterial~ will ~ recited in the dificus~ion ~ tha present e~bsdiDent, the~e lllustrate a single ~ngioplasty guide~ire embodiment only and in no way limit the ~cope of the pre~ent ~nvention.
-The ~teering device ~0 preferably i8 incorporated into a ~teerable guidewire, ~of the type ~ade from an elongate ~lexibl~ *ubular ~pring ~oil 61 h~ving a central lumen extending therethrough. ~The ~pring coil 61 ~ay ~e further provided with an outer sheath or-coating, as Ere known in the art, or the ~pring c~il may, by ~tsel~, serYe as the outer wall of the guidewire.-:As i~ well ~nown $n the art, the proximal end of tAe spring coil 61 is ~ade up o~ a plurality of ~d~acent loops oS wirs. I~t~ral rlexibility o~ th~ spr~ng coil 61 ~t a distal teering reg~on can be enhanced ~y providing ~ ~p~cing ~etween ad~acent loops of the ~pring co$1. ThesQ fe~tures ~re ~llustrated ~n Figures 1-6 of ~ pre~ious ~hodiment of the present invention, ~nd need no ~urther diacussion here.`~ lt~rnati~ely, the ad~acent loops o~ wire ~n the ~teering region cnn~be in cont~ct with one ~nother, ~ , no ~x~al spac~ng, when the ~t~ering region ~8 ~n an orlentation ~o-llnear ~ith the ~Xi8 0~ the ~djacent gui~wir~. ~e5 - -Xxtending ~xi~lly w~thin th~teer~ng region of the spring coil 61 i8 a central po8t 62. ~o~t ~2 i~ pre~erably ~ade rom a flexibl~ polymeric ~xtruslon, ~1thoug~ any of a ~d~ vari~ty of ~teri~ls can b~ -inGorporated into the post ~62 ~f ~he ~r~s~nt ~Lnven~on. Nost pr~er~bly,-the post 62 35 co~price~ ~n nylon ~rod ~ving Sa ~ubetantially ~~ircular cros~-sectional ar~a ~nd ~ dia~ater ~f about 004 ~nches.
, ~, t, ~ C 5 ~

WO90~0735~ PCT/US90/00113 ` ~:`;;` 20~5~2'~
~ 19 ~ he di~tal ~nd 64 ~f post-~2 preferab1y ~ disposed ~t or near the ~i6t~1 end of tbe ~pring ~oll ~l. For example, the di~tal ~nd ~4 $n ~ne ~mbodi~ent terminates proximally of the guidewire ~ip ~not illustrated), ~imilarly to the S embodiment ~llu~tr~tad in ;F~gure ~. ~lternatlvely, the distal end 64 is ~n ~ontact wlth the ~uidew~re tip, which can be molded or ~achined int~gr~lly ~ith ~he po~t 62 or ~ecured ther~to ~uch ~ ~y ~nown biocompati~le adhesives.
In either emhodiment,-~he distal end o~ the ~pring coil 61 0 i5 provided witb any o~ the known atrau~tic tîps conventional in the ang~opla~ty-~rt~, ~uch as those formed by molding or dipping proce~es.
Most preferably, ~he po~t ~2-4xtends in ~ di~tal direction beyond t~e di6tal ends of ~ire guid~ 72 and for a predetermined length to the di~tal Qnd of the guidewire.
Provision of such ~ length ~etween the --effective point of attachment of the guidew~res ~nd the tip of the guidewire causes the eteering region ~n ~perat$cn to ~o~m an ~el~ow"
bend, ~hich i~ ~elieved ~linically de~irable. ~n addition, the portion of ~ost 62 di~pose~ ~etween ~he end of wire guide ~2 ~nd tbe guidewire ~lp ~n ~un~tion ~as a 6afety wire for securing the guidewire `~p ~gainst -in vivo detachment~
By ~el~ow" ben~ t ~ ~eant th~t the bend in the guidewire occur~ ~t a r~latl~ely ~iscrete position ~i~placed ~roximally from the ~istal end of the guidewire.
Thi~ enable~ a ~hort.lQng~h ~f -~loppy guidewire ~t the distal end to f~cilitate ~egotiation -o~ the artery with ~inimal trauma to tbe vascular $nti~a.
~he length ~f the floppy tip ~eyond ~he ~ore rigid Rteer~ng re~ion of ~he 'guidewir~ can -~e ~ri~d, idepend~ng upon ~ number ~of cons~der~t~ons ~$~h ~ill ~e apparent to one o~ skill ln the ~rt,-inclu~ln~ the di~m~ter of the ve~el~ expectedi.to :be tr~verff~d. ~-' ~n- one ~~pecific 35 ~on~tructioA of~the embodi~ent of~~gures 7 -~nd ll, for example, ~he ~el~tive ~i~en~ion~ are Q~ ~ollows. IRngth of each of guide ~8 an~ an5hor ~2: ~bout 0.OlO ~nche~ xi~l ~ w090io735s PCTI~S90/~1l ~0 ~ 5 23 ~ 20-distance between -guide ~ nd ~anchor -72: - ~bout 0.006 inches. Distance ~bQt~een ~nd of ~nchor 72 and di~tal tip of guidewire: about~0.140 $n~hQs. ^ Di~meter of ~ontrol post 62: ~bout -0.004 -~nches. :;Dla~Qter :o~ cpring w$re of S guidewir~ body: about 0.002 inches.- ~uts$de diameter of ~ssembled gu~de~irc: about-0.014 inche~
The post 62 extends in -a proxi~al~direction through th~ spring coil -61 ~ f~r ~8 ~ay be desired for given ~ppl~cation, a will be under~tood~by lone of ~kill in the ~rt. For oxampl~, ~the central ~post -62 ~ay -extend proxi~ally only ~s ~r ~s th~ proxi~al ~ire guide 68, or further in ~ proximal direction to i~part greater rigidity to the ~pring coil ~l th~n would otherwise be present.
~he post ~2 ~ust at ~ome point ~long ~ts length be ~ecured against axial movement -~n ~he proximal direction rel~tive to the spring ~oil ~61. ~rom a manufacturing ~tandpoint, it h~8 b~-n found convenient to ~ecure the proximal wir~S guide~ 68 both to th~s post ~2 ~nd-to the inter~or surf~ces of ~pring coil ~l for thi~ pu~pose as will 20 bQ discussesd- ~oweSv~r~ th~s po~t 62 can ~l~o b~ secured to the coil 61 ~t other loc~tion~, such a5 at the proxim~l end of ~n ~xially oslongated poBt 62....~
A plurality of proximal wire guides 68 .re provided for guiding ~ wh of a plurality of deflect~ on wires 70 .
Prefer~bly, four -proximal wire ~ides 68 ~re -proYided, egually paced ~bout ~he pesriphery of ~he centr~l post 62.
As will ba app~rent~to oneS o~ ~kill ;~n the ~rt,-t~ree wire guides 68 ~ spaced :eguidi8tant -~aroun~ ~he perlphery of central post 62 will ~l~o ~llow ~omplete~360- steeratsility o~ the ~uidewirQO ~ S~owe~er~ the use ~o~ four deflection -wiro~ 70 ~ pref~rrod. ~ Si~ rly,-~hQ guidew~r~ can be con~tructed h~ving only-tvo or even a ~ingl~ proximal ~ire guid~ 68, with ~ ~Fum~nsur~t- :reductlon -ln'~h r~nge of ~otion over which th~ ~luldewir~ y ~e ~t~er~d. ai~ ~
A ~plurality -;o~ d~fl~ction 3 w~res ~q0~xtena ~xiall~~
~hroughout the longth-o~h~ ~pring~ a~h through a unique proxi~al~wira guide 68 to the d~tal:~nd 64 ~f post wo90te~3s5 PCT/US90/00113 ~ 21- 2 Og5 5 2 3 62. Prefer~bly, ~he ~ t~l ~nd 64 of po~t 62 i8 ~lso provided ~ith ~ plural$ty of ~i~tal wire ~uides 72, corre6~0nding to ~ach deflection wire~70. - --In ~ccordance ~ith ~h~ preferr~d embod~ment of ~he S present invention, Sour ideflection wlre~ 70 ar~ utilized,each deflection ~ire 70 b~ving a unique proximal wire guide 68 ~nd distal wire guide 72. ~^ ~AC~ of ~he deflection wires 70 may be secured to the di~t~l Qnd ~f the p~st ~n ~ny of a ~ariety of Danner~,2which ~illibe apparent to one of skill $n the ~rt, 8uch ~ ~y ~echanical ~nchor~, ~dhesives or thermal or chemical welding. -~:
~ owever, .it ~has -~een-1determined ~y the present inventors that ~echanical ~nchoring ~r welding of the distal end of deflectimn wire 70 ~ difficult to accomplish while providing sufficient -~trength to allow repeated ~teering ~aneuver~ of the ~teering ~dev~ce 60 without ~eparation of the ~ist~l ~nd of defl~ction w$re 70 from the di~tal ~nd 64 of pc6t ~2. : Thus, ~ltbough the preferred embodi~ent i~ ef~ectively provided ~th four ~e~lection wires ~0, ~hey ar- ~ctually two cont~nuou6 deflQction wires -which loop acro~ the di~t~l ~und 6i ~f ~the po~t 62. A
fir6t ~deflection wire 70 4xtend~ ~ictally through dist~l wire guide ~2, ~ont~nuou61y ~round or over the d~stal end 64 of centr~l ~o~t 62 :~nd b~ck proxi~ally through the opposing ;wire guide 72 ~nd -~ontinu$ng on toward~ the proximal end of ~he in~tru~ent. In this ~annQr, all four ends o~ the two continuou~ ~ir-~ t~r~in~t~ ~t ~he proximal end of the guidewire ~here they ~onnQct to ~ control ~e~ice .permitting seleCtivQ ax$al reciproc~ting ~ot$on ~here~f.
3Q In accord~nce J~ith on~ -pre~erred embod~ent ~of the present invention, prox~al ~wirc gui~e ~8 i~ ~n ~he form of ~n elongate ~tu~ular body--~or r~ceiving ~the corresponding defl~ction ~ire ~0 thorethrough. 'Ihe tu`~ul~r wire guide 68 . preferably l~ ~co~prl-9~ ~ ~~ ~ater$ai-whlc~~can-be readily ~dhered to the centr~l ~po~t 62,i~nd preferably ~i80 can be ~adhered to the ad~acent lo~p~ ~f pr~ng coil 6i. Polyi~ide tubing,.~:~uch Ya5 ~that ~anufactured ~y~ ~oly~icro WO 90/-735~ 3 -22- PCTrUS90/~l Technologies, Inc. ~n Phoenix,--Arizona,.h~v~ng ~n axial length of approximately .-010 inches and an ~n~ide d$ameter of slightly gre~ter th~n .0015 .-~nches, pre~er_bly ~bout .002 inches, has keen-found p~rticul~rly ~uit2ble for this purpose, and can be re~dily adhered to ~ nylon post 62 using ~ zuitable epoxy ~dhesi~e, such as ~hat marketed under the name Ecobond by Em~erson ~u~ing of -Canton, Massachusetts. .The length of the tubQ ~B less i~portant than the diameter, and the di~meter ~ust be suS~icient that ~ d~flection ~re extending there~hrough $~ capable of reciprocal motion with ~ufficiently low friction that steering ~ay be .accompli~hed.: The wall t~icXness of the tube will directly ~ffect ~he ~inimum diameter of the _~sembled steerable guidewire,--~nd i8 thus preferably ~inimized. For ~he polyimide t~be dis~losed ~bove, the wall thickness is pre~erably AS low as ~bout 0003 inches.
A~ illustrated i~ Figure 8, the.prox~mal wlre guide 68 is conveniently ~ffixed to the ~prlng ~oil 61 ~y ~pplying ~n epoxy 69 ther~to.
Deflection wire 70 Qxtend6 dist~lly ~eyond the ~nd ~
the proxi~al wire guide 68, ~nd preferably through a distal wire guide 72. De~lection wire 70 i5 ~ fine wire of a diameter ~ufficient-to-provide enough tensile ~trength t~
allow steering of the guidewire without breaking, but small enough to permit construction o~ guidewires suitable for angiopl~sty ~pplic~tions. ~ 3~referably,, a ~tainless steel wire i~ used, and dia2eter~ a~. lo~.a~ about ~0015 inches have been ~ound .Sunct$onally ;~ufficicnt. ; ~owever, a ~ariety of other ~et~ or poly~er~ ~ay be used, ~nd the mini~u~ appropriate^diametar for.~uny ~iYen ~aterial can ~e roadily determine~ by onQ of ~kill.-~n-th~rt.
Di~tal Yire guidQ 72 ~ ~n thQ preferrod ~mbodi~ent a si~ilar con~truction to ~r~xi~l ~ire guid~ ~68. - Thus, d~st~l ~ir~ guidefi ?2 ~are~or~ed ~y ~-plurallty-o~ elongate tubular guides.aahered to the central ~ost 62 for~r~ceiving t~ c~rre~po~ding d~fl~ction -~d~rQ 970 ~herethroug~.
. Alternat$vely, the dlstal wire gulde 72 ~can s~mply be a ~ ~0go/~73s~ PCT/US~/00113 ~ 23- 204~23 groove over the di~t~l ~nd 6~ nf poet 62, or-a ~ore hole extending transversely thr~ugh *he ~:enter of central post 62. , , : ~
A~se~bly -~Df the -~t~er~ng d~Yice ~of the prese~t invention Day ~e ~ccompli~hed ln ~-variety of ways wh~ch will be understood by one of ~ill ln the ~rt, with ~any o f the assa~bly step~ ~eing perforced under ~croscopic vision. The proxi~al ~ire guide ~8 ~nd dista~ wire guide 72, ~hen u~ed, ~re preferably sQcur~d to -the centr~l post 62 by applying ~n adhesive thereto ~uch ~ ~y d~bbing with a o0015 inch dia~eter ~wire ~ an -applicator. A first deflection ~ire -70 ~ thre~ded in a ~i~tal ~irection through corresponding -~roximal -w~re guide -68, ~rough distal wire guide 72, ~ en back ;~n ~ ~proxi~al ~irection through the corresponding wire guides on the opposite ~ide of post 62 ~nd drawn through to ~the proximal ~nd of the ~nstrument. ~his ~e~ly procedure ~s r~peated ~or ~
~econd deflection wire. ~ith -the ~efl~ction w~res 70 ~n place, the ~ntire di~tal end ~4 of po~t C2 18 dipped in or dabbed with n epoxy ~r ~ther -biologically compati~le ~ater~al ~o form a ~ap ~5 to 6ecure ~ach of the ~eflection wires 70 against ~xi~l ~ovement relative to ~he control post 62. See ~gure ~1. ~~
The entire a~6e~b1y ~f po6t '62 ~wire guides ~nd deflection ~ires iY thereafter~in6erted ~i6tal ~nd first into the proximal ~nd ~ a ~tAnd~rd ~pring coil 61 ~nd ad~anced until tbe proxi~l wire quide C8 ~ approximately ~x~lly adj~cent the ~eginning ~ the di~tal flex~le ~teer~ng region ~n the ~pring co n '61. An ~po ~ or other biocompat~bl~ ~dhe~ 69 1~ therea~ter ~pplie~ ~etween the ~ cent loop~ -of ~pr~ng ;coll-~l 'rtO ~ecure the prox~ual wire guides 68 to the ~pr~ng coil ~1, ~thereby preve~t$ng ax$al ~ovement o~.~he ~o~t ~2 rel~t$Ya ~o ~ e 6pring co~l 61. I~ haa been ~ound th~t polyi~i~e tub~nq c~n be epox~ed 35 to ~he ~d~acent spr~ng -c~il 61 ~ing ~ .002 ~nch wire or other ~ppiicator tip ~ander ~croscoplc vi~ion. ~ Bowever, care ~ust be taken ~h~t Ythe epoxy- ~oes -not~flow into WO ~/0735~ PCT/.US~/~113`
20~523 r ~ ---2 4--contact with the 1deflection w~re ~O,C-:in which case the deflection wire 70 ~ould~b~ unabl- to ol~de æx~lly within the proximal wire guide 68.
~eferring ito Figura~ 08-10; there i8 -~isclo~ed a further embodiment o~ the ~tecrlng 4evice $n accordance with the pre~ant in~ention. ~he ateering d~viGe 76 compri~es a ~ain body -7? hav$ng A -proxi~al wir~ guide 80, a wire anchor 84 and~a p~ot region 86.- Pre~erably, the wire guida 80, pivot 86 ~nd anchor 84 ~re lntegr~lly ~ormed from ~ ~ingle extrusion or ~olded p~rt. --In accordance .~ith a preferred ~mbodLment of theinvention, ~he main body 77 has ~ maximum di~eter of as small as ~bout .009 inches or smaller, and ia substantially circular in outer cros~-~ectional configur~tion, except for ~ p'urality of ~xially extending ~hannel~ 85 for -receiving guidewires 88 .therethrough.- Each of ~the channels 85 preferably ha~ a depth -of:~pproxim~tely .002 inches, ~o th~t .0015-inch diameter ~tainless ~teel-wirQ can slidably extend therethrough.. ~hannels 85 -can -conveniently be formed in thQ extru~ion process ~ ~xial recesses of the type lllustr~t-d in F$gure~ 8-10,- or ~y pro~iding parallel ~et~ of radi~lly -outwardly :extending:rlanges -which extend axi~lly to creAt~ ~ channel 85 therebetween. -Pivot 86 ~ay ke for~ed in ~ny of a variety of ~ays,25 which will be ~pp~rent-~o one ~f sXill-~n ~e art, and which will depend ~pon the construction ~ateri~l utilized.
For xample, ln ~tha ..ca~e~ ~ ~:~bermopl~stic -polymeric eYtru$ion, the pi~ot r region -i86 pra~erably comprises a radl~lly lnwardly ex*snaing .~nnul~r -~epre~sion,~ ~h~ch ~ay be for~ed by applic~tion;-~f ~t - and pre~sure or by çtretching ~ollow~g ~he ex*ru8ion proce~ ~;Alternatively, the pi~ot region ~6 can be.-~rovided ~y producing an ~n~ular reGQss ~ ough ~ther3-operht~on ~uch ~ y -physically ~illing or cutt~ng portion~ o~the 4xtru6ion away, or, ~ire guide~80 ~nd anchor 84 can ~a-~cur~d to-a -~ength ~f-meta~`
or polymeric w~r~ pac~d-.axl~lly apart ~o -provide a fi~xible l~ngthr~f~ir~ tb~rebet~en.-'~ sc ~ F'~

WO ~/0735~ PCT/USgO/00113 ; - -25- 2045~23 Prefer~bly,'~he s~eer~ng device 76 i~ provided with a deflection wire 88 at ea d o~ the four;9C- ~c~it~ons ~round the periphery 'thereo~. ~See ~igure 9.~ ~s has been previou~ly ~iscussed, ~hi~ ~an be nccomplished ~y providing four ~epar~te guidew~res ~hich are anchored ~t the ~istal end of the ~teeri~g ~ev$ce 76. ~ow~ver, four de~lection wires 88 are ~fectively proYided by assem~l~ng the ~teering deYice 76 with two continuous deflection ~ires 88, which loop o~er the di~tal ~nd of w~ra ~nchor 84 and extend back in a proximal direction as ha~ ~een discussed.
In a~embling the e~bo~i~ent of the ~teering device 76 illustrated ln Figures 8-lO,-the deflection wire~ 88 ~re pre~erably cros~ed over the distal ~nd of an extruded ~in ~ody 7~ xi~lly aligned with the free-~nds-extending in the proxi~al direction. ~he di~t~l ~nd of ~he wire ~nchor 84 is there~fter dipped ~n ~r ~abbed with ~n ~ppropri~te ~dhesive, ~uch a~ an ~poxy, to ~orm a cap~9o ~or securing the deflection wires 88 to the ~ire anchor 84.
A tubular sleeve -82,5~uch a~ a length of heat-~hrink tubing,-~6 thereafter ~pas~ed o~er the ~istal ~nd of wire ~nchcr ~4 ~nd advancQd-proximally into ~lignment with the proximal wire guide 80 ~n ~ ~nner which capture~ each wire 88 within the respective channel ~S. ~pon ~pplication of heat, the annular ~lee~e %2 reducesiin ~i~meter -to ~nugly 2~ adhere to the proximal -wire guide 80.- -It has ~een found that the use of ~hannel~ -Bl,-- having a depth of approximately -.0~2 inches, l~a~e~ a suff~c~ent toler~nce ~fter heat ~hr~nking of ~.leeve 82 o that ~tainie~s ~teel ~ires havinq ~ ~iameter of ~pproximately .~015 ~ches can freely ~xi~lly ~o~e th-rethrough. ~ -The ste~r$ng a~e~bly ~s t~er~i~ter ln~erted lnto a~tandard guide~ire ~oll ~8,~n~ adYanced until-the proximal wire gu~de 80 i~ ~pproxi~at~ly^al~gned w$th ~he~~$stal ~nd of the ~l~xible 6teering region ~f the ^C~il 78. The xadial outside surf~ce of the ~nnular 81ee~ê ~82 may therea~ter ~e secured to t~e ad~acent coil loops of co~l ~8, ~uch as by WO90/073s5 PCT~US90/001l3 ~ ~ 4 ~ ~ 2 . 26--.
thè application of ~n epoxy or other ~dhesiYe 79, as has previously been de~cribed. ,~
As w$11 be ~pparent to one of ~kill in the art, axial movement of r~ny gi~en defl~ction -wire--88 ~n ~ proximal S direction will cause ~he wire -88 to ~lide through the channel 81 in proximal wire guide 80, and, ~ec~use the wire 88 $~ im~ovably secured to the wir~ ~nchor 84, pi~ot region 86 will ~lex to permit l~teral displacement of wire anchor 84 in the direction 'of the wire -~8 which h~s been proxi~ally displ~ced. - In thi~ ~anner, ~8 ~as been described, the steering device 76 permits selective lateral displ~cement of the distal t~p in any direction, and re~torat$on of the position -~f the -distal end of the stQering device ~ack into axial alignment with ~he axis of th~ ad~acent portion o~ the guidewire or catheter.
In a ~odified version Inot illustrated) of ~he device illustrated in Figures 8-10, the pivot region B6 is dele~ed 80 that the assembled dev~ce has ~n ~nchor reglon 84 and n wire guide 80 axially spaced apart and ~ecured to the coils of guidewir- body 78. , Thu8, ~no po~t appears ~n this embodi~ent. In thi~ e~bodiment,-the deflection wires extend dista~ly ~rom the wire guide 80 toward the anchor 84 a~ be~ore, but instead of extending sUbstanti~lly parallel to the ~xi~ of the steering de~ice -76 -~8 illustrated in Figures 8 and lO, each ~eflection wire crosse~ the axis of th~ ~teering dev~ce to the opposite side thereof. Thus, for ~xa~pl~, one deflaction wir~ 70 ext~nds through wire guide 80 ~t the 90- pc~ition,-then distally:at an incline r~l~tiva to the ~xi~ of the ~t~ering dev~c~ to the 180-pos~tion on the anchor 84. ~he ~ir~ -70 thereafter in the pr~ferred embod~ment loops ~round the di8ta1 nd of anchor U and extends proxi~ally through the channel 85 ~t the 90-position th-r~o~. ~ Wire ;?4 t~r~aft-r ~xta~ds diagonally a~ro~B the .~xi8~0f ~he ~t~er~ng-4~vic~,.through the wire guiae 80 at th~ 180-~pos~tion,- and^proxiGally -~o the ~te~ring contr91~ "~ ~LO~ - G' ~
.. ..

WO90~0735~ PCT~US90/~113 .
-: -27- 20~523 As a further alternative, the di~tal ~nds ~f the deflection wires ~(which ~y ~be ~the ~idpoint ~f a long, doubled back Hire ~6 previous~y diucus~e~) Are brazed ~ir~ctly ~o the-~ire coilz o~ ~he guid~wire ~vdy. A ~razed joint i8 ~ost conv~ni~ntly ~ccompl~shed-on the outside ~urface of the guidew~re body, ~nd the deflection wires - preferably R~tend sadially ~utwardly ~etween ad~cent loop~
on the guidewire body ~or thi~ purpo~. In th~ c3se of two deflection ~ires forned ~rom a ~ingle length of wire looping around the ~t~ering -region o~ the guidewire, the deflection ~wire is .~onven~ently looped ~round the outs$de of the guidewire body to provide ~ ~ite for brazing. ~hen brazed ~oint -~ u~ed, the di6t~l-wire anchor 84 c~n be deleted. . ~
~5 Although thi5 invention ha~ been ~escr~bed ~n ter~s of certai~ preferred ~mbodi~ents, -other embo~i~ent~ that ~re apparent to those of ~ordinary ~kill ;in the ~rt ~re ~lso .Yithin the scope o~ ~hi~ lnvent~on. :~Accordingly, the ~ope of the ~nvention l~ int~nded to ~e de~$ned only by reference to the appended cla~6.

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Claims (16)

WE CLAIM:

1. A steerable guidewire for percutaneous transluminal insertion into the coronary vascular system and controlled negotiation of branches and turns therein to guide an angioplasty catheter to an arterial stenosis or other treatment site, said guidewire comprising:
an elongate flexible shaft having a proximal and a distal end and at least one lumen extending therethrough, said distal end being provided with a floppy, resilient tip;
a deflection wire guide disposed within a steering region on the distal end of said flexible shaft, said wire guide secured to substantially prevent axial displacement thereof;
a deflection wire anchor disposed with in steering region distally of the wire guide; and at least three deflection wires axially movably disposed within the lumen of said flexible shaft and extending from a distal point of attachment to the wire anchor throughout the length of the flexible shaft to the proximal end thereof;
wherein axial movement of any one of said deflection wires in a proximal direction displaces the axis of the steering region in a unique lateral direction, and through combinations of proximal axial displacement of said deflection wires, said steering region is caused to deflect laterally and rotate throughout a full 360° range of motion about the axis of the flexible shaft.

2. A steering device for controlling a flexible steering region on the distal end of an elongate implement, comprising:
a deflection wire guide having proximal and distal ends positioned within the steering region of said elongate implement;
a deflection wire anchor displaced axially in a distal direction from the wire guide; and at least one deflection wire secured to the deflection wire anchor and extending proximally adjacent the deflection wire guide;
wherein the deflection wire is axially movably disposed in contact with the wire guide.

3. A steering device as in Claim 2, wherein the elongate implement comprises a flexible catheter.

4. A steering device as in Claim 2 wherein the elongate implement comprises a flexible guidewire.

5. A steering device as in Claim 2, comprising four deflection wires and a means on the deflection wire guide for guidably receiving each of the wires.

6. A steering device as in Claim 5, wherein said means comprises an axially extending channel on the surface of the deflection wire guide.

7. A steering device as in Claim 5, wherein said means comprises an aperture through the deflection wire guide.

8. A steerable implement, comprising:
an elongate housing for transmitting a first force in a distal direction;
a resilient tip on the distal end of the housing, said tip moveable between a first position on the axis of the housing and a second position displaced radially from the axis of the housing;
at least one deflection wire within the housing for selectively transmitting a second force in a proximal direction; and a deflection wire anchor disposed in the housing for transmitting a radial component of said second force to the housing;
wherein movement of the deflection wire in a proximal direction along the housing deflects the tip from the first position to the second position.

9. A steerable implement as in Claim 8, wherein the housing comprises a flexible coiled wire.

10. A steerable implement as in Claim 9, comprising at least three deflection wires approximately equally WO 90/07355 PCT/US90/001?

radially spaced about the housing and extending axially in the proximal direction so that selective proximal movement of the deflection wires will result in a full 360° range of motion of said tip.

11. A steerable implement as in Claim 10, comprising four deflection wires radially symmetrically spaced about the axis of the housing.

12. A steerable implement, comprising:
An elongate flexible housing having proximal and distal ends and a central lumen extending therebetween, the distal end of the housing being flexible in a lateral direction;
an axially extending steering post secured in the housing, and adapted to displace the distal end of the housing in a lateral direction, said steering post having a wire anchor region and a wire guide region thereon;
at least one deflection wire having proximal and distal ends extending along the housing, said wire being attached to the anchor region of the steering post; and a control at the proximal end of the housing for engaging the proximal end of the deflection wire to cause said deflection wire to be displaced axially, in relation to said catheter;
wherein the axis of the steering post is displaced laterally in response to axial displacement of the deflection wire, thereby causing the distal end of said housing to bend out of the line of the housing longitudinal axis.

13. A steerable implement as in Claim 12, comprising at least three deflection wires.

14. A steerable implement as in Claim 12, comprising four deflection wires.

15. The implement of Claim 12, further comprising a flexible tip attached to the distal end of the housing.

16. A steerable implement as in Claim 12, wherein the cross-sectional area of the steering post at a point intermediate the anchor region and guide region is less than the cross-sectional area of the steering post in at least one of the guide region and the anchor region.