CA2102617C - Lead introducer with mechanical opening valve - Google Patents

Abstract

A transvenous lead introducer (60) having a mechanical valve assembly (70) disposed thereon. In a preferred embodiment, a longitudinally splittable introducer sheath (61) is provided with a sliding valve at or near one end. The sliding valve may be spring-biased to a normally closed position. A semicircular notch (98) may be provided in the forward end of the sliding valve, so that the sheath may be effectively sealed even when a guidewire runs through the sheath. In an alternative embodiment, the slid-ing valve is adapted to have its forward end inserted into a notch in the cylindrical sheath body.

Description

W O 93/208792 1 ~ 2 ~ 1 ~ PC~r/US93/00290 .. 1 LEAD INTRODUCER WITH MECHANICAL OPENING VALVE

FIELD OF THE INVENTION
This invention relates generally to the mPr1ic~l arts, and more particularly relates to an ~llulllent for f ^ilit~ting the intro~ on of l~vel~ous leads into the hllm~n body.
BACKGROUND OF TME INVENl~ON
The use of electric~lly cQn~luetive ll~,cl-~us leads, particularly cardiac pacing leads, is well known in the mP(lic~l field. Many di~er~ methods and tools have been proposed in the prior art for allowing such leads to be introduced into the patient's subclavian vein via a relatively small in~Cinn Often, m.o-lic~l device .~ r~chlrers may provide an introducer set to be used by doctors in ;.,g pacing leads.
In U.S. Patent No. 4,147,165 issued to Tmschinclri on April 3, 1979 and ent tle~l "Separable Needle for I~~ g a r~theter Into the Blood Stream", there is iicrlose~l a separable met~llic needle having an inner plastic sealing tube for pr~,nl,l.g le~l~e of the needle during insertion into the p~ti~nt's blood vessel.
After the needle is inserted, the inner sealing tube is removed. Thereafter, a lead is inserted through the needle into the blood vessel, and the separable needle is removed.
In U.S. Patent No. 4,166,469 issued to ~ ittleford on September 4, 1979 and çntitle~l "Al~,a~alus and Method for Inserting an Electrode", there are described several di~erenl te~hn~ çs for the intro~luction of a l~v~ ous pacing lead.
One techni1lle involves first 1>"" l~ the skin into an intçrn~l blood vessel such as the subclavian vein. One end of a guide wire is inserted into the vein by p~ccin~ the guide wire Lhrough the lumen of the nee~llp~ after which the needle is then removed leaving the guid_ wire in place. Next, an introducer and introducersleeve or sheath are slid along the guide wire to enter the vein, and the introducer and guide wire are removed, leaving the introducer sleeve in place. The introducer sleeve has sllffiriPrlt ~ mPt~pr to allow a pacing lead to then be WO 93/2087g PCr/US93/00290 inserted therein and fed into the ~ul~cla~ vein. The introducer cannot be slid back along the lead as the needle was retracted over the guide wire, since the p~cçm~kçr lead has a cor~ lor coupling disposed on its end that cannot pass through the introducer sleeve. Acco.d"lgly, the introducer sleeve is lon~ibl~lin~lly scored or utLel~.;se adapted to be lon~bl-lin~lly severed once the pacing lead has been pO~CitiQnP,~
This irst tec~ p is also described in U.S. Patent No. 4,243,050 issued to ittleford on January 6, 1981 and e~titlp~l nMethod for l~cl lillg P3cçfn~kp~r ~ Electrodes and the Like"; in U.S. Patent No. 4,306,562 issued to Osborne on Dece.. hcr 22, 1981 and entitled "Tear Apart C~nnnl~"; in U.S. Patent No.
4,346,606 to ~ ;ttlP,ford on August 24, 1982 and entitlP~ "Split-Sleeve Introducers for P cçfn~kPr Electrodes and the liken; in U.S. Patent No. 4,411,654 issued to Boarini et al. on October 25, 1983 and entitle~l "Peelable Catheter With Sec lrine Ring and Suture Sleeven; in U.S. Patent No. 4,581,025 issued to TimmPrm~nc on April 8, 1986 and entitl~d "Sheath"; in U.S. Patent No. 4,596,559 issued to ~c~ h~cker on June 24, 1986 and entitled "Break-Away Handle for Catheter Introducer Setn; and in U.S. Patent-No. 4,687,469 issued to Osypka on August 18,1987 and Pntitled "Device for Slitting Introducers For P~cefn~kPr Electrodes".
A second technique described in the T ittlçford '469 reference involves a nec~Pcc~rily larger diameter needle that is inserted into the subclavian vein. An introducer sleeve may then be inserted within the intern~l passage or lumen of the needle and into the vein, and tbe needle withdrawn over the introducer. In this second teclmique, the introducer sleeve is simil~rly adapted to be lo~itll-lin~lly severed once the pacing lead has been po.~itioned.
In a third ter~nique described in the Littleford '469 refere,lce, the inner .F,ler of i~l,udllcer sleeve is sized to closely ,~ceive the outer s~ ce of the nPeAl~, so that the needle and sleeve may be inserted into the vein cimnlt~nFously, and the needle then wilhdlawll.
A co.. nl- fealulc of any method for introd~ ne a lead into a patient's blood vessel is that a hollow, tubular i~ u~l~ent is required to provide a wo 93/20879 2 1 0 2 6 1 7 Pcr/uss3/oo29o ~' x ~
telll~ol~r p~Qsa~e or cQndllit into the blood vessel, through w_ich the lead maybe slid to enter the blood vessel. Such a conllllit also allows blood to escape from the blood vessel, and may allow air to enter the blood strea~ possibly le~-lin~ to embolic con~rli-^-^tiQn~
S In ~1rlitinn to the potential adverse clini-^Al effects of le-k~e of blood and air l}~ou~ an introducer Qhe-th, the flow of blood out of an introducer sheath is likely to make the physician's task more liffi~lt, and may e~.~ouf~ge the ~h~r~;c,~ to l,e ~o ~ the intro~hl~ion procedure more hastily. This, in turn, can case the ten~ion asso~;ated with the inl.ocl~ction procedure, and the risk that mict~lres will be made.
In the prior art, it is commonly s~l~esteA that the physician can ~revel~l (or at least restrict) the flow of blood out of a i~l.oducer sleeve while the pacing lead is being pr~arcd for intro~hlctinn into the vein by placing his or her thumb over the exposed end of the introducer sleeve. This sug~estion is made, for example, in the al,o._-noted ~ ;ttleford '050, l itt1efnrd '606, Timm~ '025, and FleiQcllh ^lrer '559 pAIf.~ A similar '~sollltion" to the 1eA1rSI~e problem that is SO...C~ -S pr cti~e~l in the art is to squeeze or pinch the exposed end of the introducer sleeve l;,ch._cn the thumb and foleLi--ger.
Neither of these methods for re~ ^in~ the ~ln~lesired flow of fluids and air through the mlloducer sleeve is deemed by the .. enlo.~ to be entirely acc~tal,le. In both cases, at least one of the physician's hands is required, thereby m~hn~ it liffi~llt for the physician to attend to other or more important m_tterS Morcover, sq~lee7in~ the exposed end of the introducer sheath can ~fO. ~.~ or even break the illlloducer at that point, m~king lead insertion difficult and in~casmg the danger of l~m~e to the lead as it passes through the uducer.
In ~ ition, neither pl~ci~ the thumb over end of the introducer, nor sq~lee7ing the end of the introducer, will be sllffi~iently effective in plcvclllhlg the flow of blood and air in the introducer once a guide wire has been threaded through the introducer. Also, the c~nff~lration of the end of some types of ,~, :' ,.

21 026~ ~
lntroducer sheaths 18 such that lt 18 dlfflcult or lmposslble to seal the end of the lntroducer shut wlth the thumb.
A trlcuspld valve system for catheter (as opposed to lead) lntroducers 18 also deemed to be unacceptable for use ln con~unctlon wlth lead lntroducers. The trlcuspld valve arrangement for catheters could damage the sensltlve lead tlp of a paclng lead. The appllcatlon of pressure requlred to open the trlcuspld valve can result ln dl~tortlon or breakage of the lead tlp. Moreover, some presently known trlcuspld systems are lubrlcated wlth slllcone-based oll. The electrlcal propertles of paclng/senslng leads, and the chemlcal propertles of sterold-elutlng lead tlps and the llke, can be severely effected by comlng ln contact wlth the oll.
It 18 belleved by the lnventors, therefore, that there 18 presently a need for a method and apparatus for preventlng the undeslred flow of alr and blood ln an lntroducer sheath prlor to the lnsertlon of a cardlac paclng or senslng lead.
SUMMARY OF THE INVENTION
In accordance wlth the present lnventlon, an lntroducer sheath for lmplantlng transvenous cardlac paclng and senslng leads 18 provlded ln whlch the flow of blood and alr 18 slgnlflcantly reduced wlthout requlrlng a physlclan or surglcal asslstant to malntaln constant pressure on the end of the lntroducer sheath. Also ln accordance wlth the present lnventlon, the means for preventlng blood and alr flow through the lntroducer sheath does not lmpalr the sheath~s ablllty to accept a lead thereln, and whlch does not lncrease the rlsk of damage to the lead as lt 18 belng lntroduced lnto the patlent.

A~ 66742-444 : `~

2 1 ~

Further ln accordance wlth the present lnventlon, there 18 provlded a means for allowlng the physlclan to qulckly, slmply, safely and repeatedly effect a temporary seal over the lntroducer sheath, prlor to lnsertlon or relnsertlon of the lead.
In accordance wlth the lnventlon, an lntroducer sheath of the type that 18 longltudlnally spllttable 18 provlded wlth a mechanlcal openlng valve dlsposed on or near lts proxlmal end. The valve 18 operable to sllde lnto place over the proxlmal end of the lntroducer sheath after the vessel dllator and gulde wlre have been wlthdrawn, such that the flow of blood and alr through the sheath 18 prevented.
The lnventlon may be summarlzed, therefore, as a transvenous lead lntroducer comprlslngs a longltudlnally spllttable lntroducer sheath havlng a hollow cyllndrlcal body, open at lts proxlmal and dlstal ends; a tab dlsposed at the proxlmal end of sald lntroducer sheath, extendlng radlally outward therefrom7 a slldlng valve dlsposed on sald tab, sald ; slldlng valve adapted to sllde from a flrst, open posltlon whereln a forward end of sald valve 18 dlsposed over sald tab, to a second, closed posltlon whereln sald forward end 18 dlsposed over sald open proximal end of sald lntroducer sheath; such that sald valve, ln sald closed posltlon, substantlally prevents the passage of alr and blood through sald sheath.
In a speclflc embodlment, the slldlng valve may be provlded wlth a semlclrcular notch on lts forward end, 80 that the valve may be closed around a gulde wlre lf the gulde wlre 18 left ln the veln, such as durlng a multlple lead A;

-210~6~7 lmplantatlon procedure.
In another embodlment of the lnventlon, the slldlng valve 18 provlded wlth a horlzontal groove on lts forward edge, ln addltlon to the gulde wlre notch. The horlzontal groove 18 adapted to engage a complementary collar dlsposed around the clrcumference of a vessel dllator's proxlmal endplece, 80 that the lntroducer sheath and vessel dllator remaln statlonary wlth respect to one another as the lntroducer 18 lnserted lnto the blood vessel. When the slldlng valve 18 pulled back and the vessel dllator wlthdrawn, the valve may then be closed as ln the flrst embodlment.
In stlll another embodlment of the lnventlon, the slldlng valve 18 provlded wlth a sprlng element dlsposed on lts underslde, the sprlng element tendlng to keep the valve ln a closed posltlon over the top of the lntroducer sheath unless the valve 18 pulled back.
In yet another embodlment of the lnventlon, the slldlng valve 18 housed wlthln a houslng dlsposed at some polnt along the length of the lntroducer sheath where a notch 18 provlded to recelve the forward end of the slldlng valve.
In another embodlment of the lnventlon, a unltary houslng 18 provlded at the proxlmal end of the lntroducer sheath. Protrudlng from opposlte sldes of the houslng are sprlng compresslon elements whlch normally obstruct or seal the end of the sheath, but whlch, when depressed as by squeezlng between the thumb and foreflnger, expose the end of the sheath.

- 5a -. ~

21 02~ 7 ~ BRIEF DESCRIPTION OF THE DRAWINGS
The foregolng and other aspects of the present lnventlon wlll be best appreclated wlth reference to the detalled descrlptlon of a speclflc embodlment of - 5b -A~ ' ' wo g3/20879 PCr/US93/00290 ~ ~102617 the invention, which follows, when read in conjllnction with the ~ccolllp~ g drawings, wherein:
Figure 1 is diagram illuslld~ g the pl~c~PmP,nt of a p~PTn~ker and pacing/sensing leads in a p~tiPnt;
S Figure 2 is a d~ illui hdliug an ,~ iate entry site for impl~nt~ti of a tl~.eilous cardiac pacing/se~ g lead;
Figures 3 through 14 are diagrams illuslldting succe-~ e stages of a prior art Ll~e~ù.~s pacing/sensing lead hll,u~ cti~n procedure;
Figure 15 is a diagram of a lead introducer in accordal,ce with one - 10 e~bo.l;.. ~.-l of the l~leelll invention;
Figure 16 is an enlarged top view of the introducer sheath of the o~lucer of Figure 15;
Figure 17 is an enlarged pe..~pect;vc view of the sliding valve of the introducer sheath of Figures 15 and 16;
Figure 18 is an enlarged per~pective view of a lead i~ oducer in accorda~ce with another embo~lim~-nt of the present invention;
Figure 19 is an enlarged pe.~l-cc~;~e view of the lead introducer of Figure 18;
Figure 20 is an enlarged perspective view of a portion of the introducer sheath of the introducer of Figure 18;
Figures 21 through 25 are pcl~ective, front, top, side, and bottom views of the ~ `c~ valve of the i~ ducer of Figure 18;
Figure 26 is an enlarged pc- ~e~ c view of a lead introducer in accorda~ce with another e l"I,od;...~nt of the ~l~enl invention;
Figure 27 is a l,c,~c~i~,e view of the sheath from the introducer of Figure 26;
Figure 28 is a l~el~eclivc view of the sheath and valve housing from the i~l,ud~lcer of Figure 26;
Figure 29 is a ycl~ycctive view of the valve from the introducer of Figure 26;

. .

.

Wo 93/2087g Pcr/us93/00290 ~7; ~102617 Figure 30 is a perspective view of the huu~ g cover from the introducer of Figure 26;
ri~u~es 31, 32, and 33 are top, side, and bottom views, re~ecli~,~ly, of the valve from the introducer of Figure 26;
Figure 34 is a cross se~ l view of the m~od~cer of Figure 26;
Figure 35 is a top view of an ~ t;~e embo~imPnt of the valve from the illlr~d~cer of Figure 26;
Figure 36 is a l,c-~ec~;~e view of the ~lle...~ embo~liment of the valve from the introducer of Figure 26;
Figure 37 is a ~l-c.~;vc view of an i~ uducer in accordance with another embo~liment of the yr~s~nl invention; and Figure 38 is a cross-section~l view of the i~ o.lucer af Figure 37.
DET~ DF-~CRIPIION OF SPECIFIC EMBODIMENTS
OF lH~ INVENTION
Figure 1 depicts a typical ~_.. g~ n~ of a pacing system impl~nted in a patient 10, the pacing system ç~ a sul,--vl~.cously disposed p~ce-m~kçr 12 and l-~ous pscing/se-~ g leads such as 14 and 16. In Figure 1, the distal end of pacing lead 14 is shown (licpose~ generally in the atrial region of the patient's hesrt 18, while the distal end of pacing lead 16 is disposed generally in the ventrir~ r region of heart 18. It is to be ~ e,~loo~l of course, that the present invention is not limite~l to use in illllûd~ring only atrial or ventricular leads, and may be employed in intro~luring many of various types of L~u~svc lous leads int~-nded to be d~osed at various places within patient 10, in~ ing for example, leads int~.n~e-l to be di~osed wi'~hin the patient's corul-~y sinus.
The pref~led prior art m~th~ of lead ~lloduction co.. ~ ;hle with an introducer in acco.dal-ce with the presently (1i~close~l embodim~ns of the invention will be ~l~s~ betl with reference to riE,ulcs 2 through 14.
Rer ~ ;ue to Figure 2, and in accûrd~ce with co-....... - .~ practice in the medical arts, the entry site for a su~cldvial- vein ~ullctuie is a?mrnOnly chosen to be just below and slightly medial to the jl~n~ tion of the middle and inner third of the davicle WO 93/20879 Pcr/us93/00290 ~'-"210~617 8 20, at an area lçcierqted generally as 22 in Figure 2. In Figure 2, the patient's subclavian vein 24 and heart 18 are shown in ph~nt~m Turning to Figure 3, the sub~l~Yi~ vein puncture is qccomrlished by the physician using a disposable syringe 26 having a thin-wall needle 28 detachably co~ 1e~ lLere~o. Aspiration is ~ d as the needle is advanced into the sul~claYiall vein, to verify proper needle pl~cçln~nt within vessel 24. Next, asl,ila~ g syringe 26 is ~iicco.-~.ccled from needle 28, which r~ s in vessel 24 as shown in Figure 4. Typically, the physician will phce his or her finger over the needle to avoid air as~ation and ~ ~cessi~e blee~
The next step in the lead ;.. ~ ;on procedure involves insertion of a co~v~ nn~l J-type guide wire 30 through needle 28, as illustrated in Figure 5.
Typically, guide wire 30 is cqui~?ed with a tip dçflectQr 32 for f~ilit~ting insertion of wire 30 into the lumen of needle 28. As shown in Figure 6, as wire 30 is fed ll~ougll needle 28 in the direction of arrow 34, the distal end of wire 30 exits the tip of needle 28, and wire 30 re ~ its "J" shape within vessel 24. Once wire 30 has w~ cd vessel 24, needle 28 is wilhd.a~vn in the direction of arrow 36 in Figure 7, leaving wire 30 in place. Wire 30 is a~ced along vessel 24 until its distal end is disposed generally in the area of the patient's s~lperior vena cava, leaving a~pro-;...~tely 15 to 2~cm of the pr~al end of wire 30 exposed.
A small sldn in~c;on 38 is made at the guide-wire entry site, parallel to the clavicle, as shown in Figure 8. In the next stage of the impl~nt~tion procedure, an i lhu~h~cer sheath 40 with tapered vessel dilator 42, as a unit, are threaded onto the o~al end of wire 30. Sheath 40 and dilator 42 are adv~c~d in the direction of arrow 44, through the sub.la~ian fascia and into the su~cla~i~ vein 24, until a short length (e.g., 2 to 8-cm) of sheath 40 and vessel dilator 42 remain exposed, as shown in Figure 9.
Next, as shown in Figures 10 and 11, vessel dilator 42 is withdrawn in the direction of arrow 46, leaving i~ oducer sheath 40 and guide wire 30 in place with its distal end Ji~l,osed within subclavian vein 24. Guide wire 30 may be removed at this point as well, ~ltho Igh it may be left in place in case the lead needs to be WO 93/2087g PCr/US93/002gO
a ~ 1 0 2 6 1 7 r~o~;l;onP~l or re~3~led. As shown in Figure 11, introducer sheath 40 would provide an !-..ob~ cted cnn~hlit for blood to exit subclavianvein 24, and at the stage of lead ~ y~ rn ~lepi~ed in Figure 11, blood could be allowed to escape. In the prior art, as previously noted, it has been sn~gested that the escape of blood and air as~ alio.l at this stage of the ;"~ "1~t;r~n ploce.lule may be re~lucecl by placing a thumb over the y ~Ai..,al end of introducer sheath 40, or by s~lvee~ing the pio~ al end of sheath 40.
In the final stages of the lead ;..~ t;on procedure, illustrated in Figures 12 through 14, pacing lead 14 is inserted into the ~>r~lal end of introducer sheath 40 in the direction of arrow 48, and ad~ ced into the desired position within patient 10. Lastly, i~Lloducer sheath 40 is r~ d. . Removal of introducer sheath 40 may be ~co~r~l;c-he~l in one of several known ways, depending upon the particular type of introducer sheath 40. For e~ le, as dicr~loserl in the above-noted Osborne '562 patent, sheath 40 may be lo~ihldin~lly split by pulling tabs 50 and 52. Other she~thc are known which are severable by means of a special slitter device or the like.
As shown in Figure 1, ~, ce-m~ r 12 may operate in colljullction with two pacing leads. ~n that case, as with single-lead ;..~ L~, it may be ..eces~ to keep - guide wire 30 in place until after the first lead has been implanted. Thus, aspreviously noted wi~h referel-ce to Figures 10 and 11, guide wire 30 may be left in place when dilator 42 is withdrawn. The first lead, if it is sllffi~ently small, may be introduced into su~cl~i~ vein 24 ~longs;(lç guide wire 30, and then the first introducer sheath is r~ o.ed leaving guide wire 30 in place. Then, a second introducer sheath and vessel dilator can be guided along guide wire 30 in the same .-.~...1-. as the first, before guide wire 30 is finally removed.
As would be a~ar~l to one of or~ sldll in the art, leaving guide wire 30 in place while the first lead is implanted further reduces the physician's ability to restrict l,l~e~lin~ and air a~alion ~lOu h the first introducer sheath, since guide wire 30 will pr~ l either the physician's thumb or the sqtlee7ing of introducer sheath from tightly sealing the sheath.

Wo 93/2087g ; PCr/US93/00290 ~2iO2617 lo Turning now to Figure 15, an introducer 60 in accord~ce with one eml)o.~ l of the present h~vclllion is illusllated. Introducer 60 co~ ises an ~t~oducer sheath 61 in which a vessel dilator 66 is il~ ed. A tapered end 68 of vessel dilator 66 fr^ilit~tes the intro~u~c~n of sheath 60 into the subclavian vessel.
Ther~ler, guide wire 30 and vessel dilator 66 are withdrawn from the p~tient In the el-lboA;...rnt of Figure 15, sheath 61 of the type that is re.n.,._d from a pacing lead by being lo~hl(lin~lly splitti~ apart. In particular, introducer sheath 61 is split apart by glas~ g tabs 62 and 64 as it is being withdrawn from the lead introdu~tion site, ~ o~ it is believed by the illvenlol~ that the ylesenl invention could also be advantage~ sly employed in conj~ m with introducer ~he~th~ that are rc",~,able by other means, such as by a sheath slitter or the like, as is c~)mmonly known in the art.
As shown in Figure 15, and in accolda,lce with a plilll~ aspect of the presently rlic~ secl embo~l;...enl of the invention, a sliding mPc~ni~l valve 70 is ~ osed on tab 62 of introducer 60. As will be her~in~rl~r described in ~lealer detail, valve 70 is m~ml~lly slidable in the direction of arrow 72 to substantially cover the circular ~ at the end of sheath 61 between tabs 62 and 64.
- Operation of ...~cl-A~ al valve 70 may be better a~t,.e~ ;ated with reference to Figure 16, which is a greatly enlarged end view of inlloducer 60, looldng down upon tabs 62 and 64, axially along the cylindri~l body of sheath 61. In Figure 16, vessel dilator 66 has been rclllo~ed from sheath 61, and valve 70 is shown in a 'closed' position~ such as to effccli~ely cover and seal the top end of cylindrical sheath 61, the circular outline of which being d~si&r~te~l by a dotted line in Figure 16. In the embo~ .l of Figure 16, valve 70 is inset within a shallow well 74 in the upper s~ e of tab 62, with well 74 having a cu~ed end 76 sllbsl~ lly con~wll~ g to the shape of valve 70. Valve 70 may be slid in the direction of arrow 78, thereby U~C ,.c.illg the top end of cylin~lnc~l sheath 60. Valve 70 having been moved to the 'open' position is ~lepi~ted by dotted outline 80 in Figure 16.
In Figure 17, a greatly enlarged pc.s~e~:livc; view of sliding valve 70 is shown.
The top of valve 70 is provided with a series of sawtooth ridges 82, aUowing the WO g3/2087g PCr/US93/002gO
ll 2102617 physician to easily slide valve 70 back and forth within well 74 with only slight dc,wll~.drd yr~SDul~.
On each side of valve 70 is a ho. ;,.~ 1 track such as track 84 shown in Figure 17. Tracks 84 are ~-~n~ecl in ~.es of a co~r~ g size disposed along the 5r~Dyp~:live inner side walls of well 74. The grooves in the side walls of well 74 will be more readily .l;~f~,. ..;hle in later Figures.
It is cQ~ te~l by the m~n~ that in the above-described embo~limPnt of the invention, as well as in later el"l,o~l;..~f~ , the i~ oll~cer sheath tabs can be made of polyethylene or any other suitably rç~ ont and stçrili7~ble m~ter~
~ltho~leh the use of a particular .. ~tc . ;~l is not ~eemed to be ~bsollltçly essential to the s~loccs~ll practice of the ylese~ll invention. It is also believed that the cer of the y.csc"l and later embo~1im~nt~ of the invention can be readily adapted by a person of ordi~ skill in the art to any of the various sizes of ce.rs conlmc~nly known and used.
15One fealu,e of the embo~ pr~t of the invention described above with - ref~,lellce to ~i~;ules 15 through 17, as well as of the embo l;...P~ll to be here;~rler described with referel~ce to Figures 18 through 25, is that the size and shape of the sliding valve may be chosen so that the same part can be used in the ...~ r~ re of intro~lncers of various sizes; that is, the size of the valve and related components 20need not be ~ O~ C~ for a particular size introducer sheath. In ~d~lition, it is contçmplated by the il-vel~lol~ that the valves in introducers in accorda"ce with any of the embo~ L~ of the invention lic~lose~ herein can be color-coded, such that a physician can identify the size of the introducer sheath by quick referel,ce to the color of the valve.
25Turning now to Figure 18, a ~cl~c.li~e view of a slightly different e~o~l;...~--.l of the ~;esellt invention is shown. In Figure 18, the individual introducer co~l)ol,ents have rct~ 1 the same refere~ce numerals as those of the e~bo~l;...~-nt of Figures 15 through 17, but are followed by a "dash one" (-1) suffix.
In Figure 18, i~ oducer 60-1 is shown with a vessel dilator 66-1 inserted into sheath 61-1. As in the embotlim~nt of Figures 15 through 17, introducer 60-1 is of WO g3/20879 ' ' PCr/USg3/002gO
21~2617 12 the type in which sheath 61-1 is removed from around an implanted lead by grasping tabs 62-1 and 64-1 and pulling, .~ g sheath 61-1 to split lon~ lin-s-lly away from the lead, the line of the s~ g being de~ ul in Figure 18 by a dotted line 86-1.
In the embo/lim~nt of Figure 18, sliding valve 7~1 is provided with a groove 88-1 along one end which is car-s-~- of çng~ an snnlllsr collar 90-1 disposed onthe p u.~i~al end of vessel dilator 66-1. With this &r~ g,~...ont vessel dilator 66-1 may be secured in place in sheath 61-1 and be ~e~ ed from sliding back out of sheath 61-1 as in~ cer 6~1 is inserted into the ~ubcla~ vein. The ability to lock dilator 66-1 is believed to be advantageous, since dilator 66-1 may be pushed out by venous ~.cs~ure or venous ~ to~ , espec~slly if there is low fricti--n or a loose fit bct~.ccn dilator 66-1 and sheath 61-1. With the locking ...rch~..;.~... of the e~ o~ nt of Figure 18, the physician need not be co~.c~-~.P--l with the relativepo~ ..c of dilator 66-1 and sheath 61-1 as the introducer is being inserted. Once sheath 61-1 has been ~r~clly positinn~ within the subcla~i~ vein, valve 70-1 maybe slid baclc (in the direction of arrow 92-1 in Figure 18), allowing vessel dilator 66-1 to be re~ d from sheath 61-1. Then) valve 70-1 can be slid into place such that it covers and seals the top of c31;...h;c~l sheath 61-1.
In Figure 19, a side view of introducer 60-1 from Figure 18 is shown, wherein such fealulcs as groove 88-1 in sliding valve 70-1, and collar 90-1 of vessel dilator 66-1 are somewhat more a~arclll than in Figure 19. As in the embo~iiment of the invention ~escribe~l with ref~ellce to riE,~cs 15 through 17 above, sliding valve 70-1 is disposed within a well 74-1 in tab 62-1, and valve 7~1 is provided with ho. ;~o..l~l tracks 84-1 which are rec~ d in co ~fu~ ~oû~es~ one of which is de-sign~te~l as 94-1 in Figllre 19, in the side walls of well 74-1. It is to be noted from Figure 19 that grooves such as 9~1 need not extend the entire length of well 74-1, but in~te~d may - te-.. ;.. ~te at the point ~ci~.a~ed generally as 96-1 in Figure 19. As a result, valve 7~1 is pr~ ~cihlcd from being separated from tab 62-1, even when sheath 61-1 is split apart. This is believed to be desirable from the st~n~roint of not allowing a small piece of introducer 6~1 to be lost during the surgical plAn~ ;on procedure.

WO 93/20879 ~ 1 0 2 6 1 7 PCr/US93/00290 13;

The extent of grooves 94-1 in the side walls of well 74-1 can be more readily apprc~ ted with refercllce to Figure 20, which is an enlarged perspective view of a portion of introducer 60-1, in~lu~ling tabs 62-1 and 64-1, but having sliding valve 70-1 removed. Figures 21, 22, 23, 24, and 25 are pel~e~ive, front, top, side, and bottom views, res~c~ ely, of sliding valve 70-1 from the embo~limpnt of Figures 18 and 19.
In Figures 21, 23, and 25, another fealule of the prcsclllly disclosed embodimPnt of the ~lesenl invention is shown, in particular, a semi-circular notch 98-1 disposed in the front edge of valve 70-1. Recall from the foIeg~ g ~lic~lccion of the lead impl~ ;o.~ procedure that in the case that h,vo leads are to be i~ ed during one procedure, it may be desirable to leave guide wire 30 in the subclavian vein while the first lead is introduced, so that the guide wire is available for g~ ing the il~ d~.ction of a second hlllo~cer sheath and vessel dilator. In that case, the problems with blood le~lrage and air asl,~alion are further exacerbated by the fact that the guide wire reduces the effectiveness of pl~ng a thumb over the top openine of the sheath or of p;,.-~l,;"~ the sheath closed.
Semi-circular notch 98-1 in valve 70-1 is l,lerelably the same size as guide wire 30, so that when valve 70-1 is slid into a closed pocition, guide wire 30 is received within notch 98-1, sllbst~nti~lly completing the seal over the top of sheath 61-1. If no guide wire is present when valve 70-1 is closed, valve 70-1 is able to slide slightly further over the top of sheath 61-1, so that notch 98-1 is advanced slightly past the top of sheath 61-1.
Turning now to Figure 26, a pe.~e~;vc view of another embo-liment of the present invention is shown, the components thereof being desi~n~te~l by reference lelals followed by a "dash two" (-2) suff~. In the embo~liment of Figure 26, introducer 60-2 has a tab 62-2 disposed on the distal end of introducer sheath 61-2 CQ.,~ S a sliding m~cll~ni~l valve 70-2. A second tab 64-2 is considered optional in this embo~lim~nt and is ~ercfore shown in ~ tc..~ in Figure 26.
Tab 62-2 in Figure 26 col~ es a housing 100 2 and housing cover 102-2.
With referellce now to Figures 27 through 34, various stages in the assembly of introducer 60-2 will be described. Assembly of introducer 60-2 begins by forming a WO g3/20879 PCI/US93/1~02gO

notch 104-2 near the pr~ al end of cylindrical sheath body 61-2, as shown in Figure 27. Next, housing 100-2 is fitted over notch 1û4-2, as shown in Figure 28. Housing 100-2 tl~finPs a first shallow well 74-2 which receives sliding valve 70-2. Well 74-2, in turn, has a se~on~l deeper well 106-2 disl,osed therein, for receivillg a spring el~m~nt on the lm~l~rsidp of valve 70-2, to be here;.. ~*er described with ref~el.ce to Figures 32 throu~ 34.
As shown in Figure 29, valve 70-2 has a ~lw~d end 108-2 which is curved to s..~sl~ lly cc...r.~-... to the inner wall of sheath 61-2. After valve 70-2 is fitted into well 74-2, houci~ cover 102-2, shown in Figure 30, is secured, as by sonic bonding or the like, onto housing 100-2, resulting in the fully ~ccembled tab 62-2 shown in figure 26.
Figure 31 is a top view of valve 70-2. Figure 32 is a side view of valve 70-2.
A ridged l.rol,usion 110-2 ~yten~lc through a re~t~.~g,ll~r hole 112-2 (see Figure 30) disposed in housing cover 102-2. On the o~,o~ile face of valve 70-2, a spring elemP-nt 114-2 is forme~l being ~tt~he~l to valve 70-2 at a point ~eci~n~te~l generally as 116-2 and having an nn~tt~ehed end ~leP;~ ted 118-2 in Figure 32. The ctm-fig~lration of spring el~-ment 114-2 may be better appreri~ted with reference to - Figure 33. Spring elen1~nt 114-2 is made of polyethylene or another suitably resilient le~ ;~1 and has a snbst~nt~ y curved shape which is capable of being col,lplessed in les~ lse to applir~tion of force directed on its nn~tt~rhed end 118-2 in the direction of arrow 120-2. Spring element 114-2 in a co-~ressed state is illustrated by dotted line 122-2 in Figure 33.
Operation of valve 70-2 will now be described with reference to Figure 34.
In Figure 34, valve 70-2 is shown in a 'closed' position~ such that forward end 108-2 PYt~n~l~ thlo.~ll notch 104-2 and is held in cQnt~ct against the inner wall of sheath 61-2, thereby sealing sheath 61-2. Spring element 114-2 biases valve 70-2 into the position depicted in Figure 34, so that sheath 61-2 is nonn~lly sealed. Upon applir~ n of force on ridged l rol~ u~ion 110-2 in the direction of arrow 124-2, spring element 114-2 is co~ essed against a back wall 126-2 of well 106-2, such that fo.~.drd end 108-2 of valve 70-2 is retracted out of sheath 61-2, thereby leaving wo 93,2087g 2 1 0 2 6 1 ~ PCr/US93/00290 ~ ~S ,., ~ .~
sheath 61-2 open and unobstructed. When force on ~,ollusion 110-2 is removed, spring el~prnpnt 114-2 ~eco~ resses, restorin~ valve 70-2 to its closed position and rese~ling sheath 61-2.
In the forcgoillg desc,iplion of the ~re_nl embo~liment of the invention, it has been ~C~ .rd that the colll~ol.cnts are made of relatively rigid m~tçri~l such as polyethylene or the like. It is conlr~ .lated by the ill~entola~ huw~ver, that a better seal may be achieved between the fol-.~rd end 108-2 of valve 70-2 and the inner wall of cylin-lric~l sheath 61-2 if valve 70-2 had a col-l~osile COllall~CtiOn as depicted in riy,urcs 35 and 36. In particular, it is conte.~ te~l that valve 70-2 may comprise a first, rigid valve body 71-2 having a rigid fOl. ald plolluaion 73-2 eYtP-n-ling~cr~o~, around which a more resiliP-nt (e.g., silicone rubber or the like) end piece 108-2 may be fitted. End piece 108-2 may be moltl~P~ as shown in Figure 36 with a cavity 126-2 therein for en~in~ rigid l)rolluaion 73-2 on valve body 71-2.
Yet another embodiment of the present invention, depicted in Figures 37 and 38, is c( ntPrnrlated by t_e h~vellto.~. It is believed that the embo-limPnt of Figures 37 and 38 is best suited for non-splitt~ble introducer ~he.~th~ As shown in Figure 37, introducer 6~3 colll~lises a ul~ilal~ endpiece 130-3 disposed at the distal end of a cylindrical sheath body 61-3. Endpiece 130-3 has coll.~lession elem~nt~ 132-3 and 134-3 eytenrling oulward from its ends. Introducer 60-3, like introducer 60-2 previously described v~ith lefercllce to Figures 26 through 36, is biased to a normally 'closed' or sealed conclition; 'opening' or nn~e~lin~ sheath 61-3 in the embodiment of Figure 37 is ~ccompli~hed by ~slaaplug endpiece 130-3, as betw-een the thumb and forefinger, such that collll,ression element~ are forced inward.
Operation of the co~ re~sion elements of Figure 37 will be best appreci~te~l with reference to Figure 38, wherein collll~lession element~ 132-3 and 134-3 areshown to be identical, o~osilely-oriente~l and interlocking. In the state shown in Figure 38, the circular end of sheath 61-3 is completely obstructed, half by colll~esaion element 132-3 and half by coll~l~ssion elemPnt 134-3. When force is.ciml~lt~nf~ously applied in the directions of arrows 136-3 and 138-3, colll~lession element 134-3 is co~essed a~in.ct coll,~rcssion elem~-nt 132-3, and el~ment 132-3 Wo g3/20879 PCr/US93/00290 is coJl,~ressed ~ nct elerntont 134-3, thereby e~o~ g the end of sheath 61-3. The extent to which co~ )ression elementc 132-3 and 134-3 is mnt~ ly ~letermined by the two elçm~ntc cQmine in cQnt~ct with each other. In particular, as shown in Figure 38, the point of el~rnent 132-3 ~ledgn~teA as 140-3 will cont: ct elem~nt 134-3 at the S - point ~lesi~te~l 142-3; likewise, the point on elern~nt 134-3 d~-ci~te~l 146-3 will contnct point 144 3 of e~ 132-3.
From the ior~going ~let~ile~l description of specific embo~limentc of the invention, it should be a~are.ll that means for restricting the flow of blood and air through a l~ nous lead introducer sheath have been disclosed. While particular embo-liments of the invention have been described herein in some detail, this has been done for the purposes ofillustration only, and is not intenrle~l to be taken as l;...;l;..g the scope of the presenl invention as ~l~finel1 in the appended daims. It is cQnte~ ted by the i.l/t;nlols that various alterations, sllbstitlltiQncJ and mf~-lific~tiQnc may be made to tbe l;cclrse1 embo~ f -~LC of the invention without d~a~ g from the spirit and scope of the ~;~s^nt invention, as d.o.fin~-l in the claims.

Claims (6)

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

1. A transvenous lead introducer comprising:
a longitudinally splittable introducer sheath having a hollow cylindrical body, open at its proximal and distal ends;
a tab disposed at the proximal end of said introducer sheath, extending radially outward therefrom;
a sliding valve disposed on said tab, said sliding valve adapted to slide from a first, open position wherein a forward end of said valve is disposed over said tab, to a second, closed position wherein said forward end is disposed over said open proximal end of said introducer sheath;
such that said valve, in said closed position, substantially prevents the passage of air and blood through said sheath.

2. An introducer in accordance with claim 1, further comprising:
a vessel dilator, having a hollow, substantially cylindrical body, a conically tapered end, and a flared endpiece adapted to facilitate insertion of a guidewire into said dilator, said dilator being adapted to be inserted, tapered end first, into the proximal end of said introducer sheath, such that said flared endpiece is brought into contact with said tab.

3. An introducer in accordance with claim 2, wherein said flared endpiece has an annular collar disposed therearound, and wherein said forward end of said sliding valve has a horizontal groove formed therein for engaging said annular collar and securing said sheath to said dilator.

4. An introducer in accordance with claim 1, wherein a guidewire is inserted into said introducer and wherein said forward end of said valve has a notch formed therein, adapted to engage said guidewire therein when said valve is slid to said closed position before said guidewire is removed from said introducer, such that passage of air and blood through said sheath is substantially prevented.

5. An introducer in accordance with claim 1, wherein said sliding valve is spring-biased to assume a normally closed position.

6. An introducer in accordance with claim 1 comprising a further tab disposed at the proximal end of said introducer sheath, the further tab being generally aligned with the first mentioned tab but extending radially outward from the sheath in an opposed direction, whereby the sheath may be split by grasping and pulling apart the two tabs.