US20050080472A1 - Lead stabilization devices and methods - Google Patents

Abstract

Devices and methods for stabilizing a lead in a cardiac vein.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS
• This application claims the benefit of U.S. Provisional Patent Application No. 60/510,663, filed Oct. 10, 2003, entitled LEAD STABILIZATION DEVICES AND METHODS to Atkinson et al., the entire disclosure of which is incorporated herein by reference.
FIELD OF THE INVENTION
• The present invention generally relates to medical devices and methods. More specifically, the present invention relates to medical devices and methods for stabilizing leads in cardiac vasculature.
BACKGROUND OF THE INVENTION
• Heart failure is an increasingly common condition worldwide. Cardiac resynchronization therapy (CRT) has shown great promise as a treatment for a large percentage of patients in various stages of heart failure. CRT involves cardiac pacing of both the left and right ventricles of the heart (biventricular pacing), which causes both ventricles to beat simultaneously, greatly improving the pumping efficiency of the heart. Typically, the lead that stimulates the left ventricle is positioned via the coronary sinus into a cardiac vein along the free wall of the left ventricle.
• There are numerous challenges in successfully positioning the left ventricular lead, including accessing the coronary sinus and veins, advancing the leads to a position which yields proper stimulation, and preventing subsequent lead dislodgement during removal of delivery devices. Post procedural challenges related to the left ventricular lead include lead dislodgement prior to fibrosis, loss of stimulation capture, and lead removal necessitated by infection.
• Currently available left ventricular leads have generally been designed to facilitate effective delivery and provide fatigue resistance, and are particularly susceptible to dislodgement both intra-procedurally and post-procedurally. Efforts to incorporate more aggressive anchoring into the lead body have generally been insufficient for preventing dislodgment, and/or have compromised effective delivery, fatigue resistance and subsequent lead removal.
SUMMARY OF THE INVENTION
• Therefore, a need exists to enable effective lead stabilization without compromising lead delivery, resistance to lead fatigue, or lead removal. To address this need, various exemplary non-limiting embodiments are described herein which provide devices and methods for acute and/or chronic lead stabilization. By way of example, not limitation, the lead stabilization mechanisms described herein may be separate from but cooperative with the lead, thus allowing independent delivery and function. To this end, the lead may be designed for effective delivery and fatigue resistance, and the stabilization mechanism may be designed for effective acute and/or chronic anchoring to prevent lead dislodgement. In addition, the stabilization mechanisms described herein may be separable from the lead to permit subsequent lead removal.
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1 is an anterior view of a human heart and associated vasculature;
• FIG. 2 is a posterior view of a human heart and associated cardiac venous vasculature;
• FIG. 3 is a schematic side view of a lead and an anchor device in the form of a stent disposed in a cardiac vein;
• FIG. 4 is a schematic side view of a lead and an alternative anchor device in the form of a stent disposed in a cardiac vein;
• FIG. 5 is a schematic side view of a lead disposed in a coronary vein and an alternative anchor device in the form of a stent disposed in a secondary cardiac vein;
• FIG. 6 is a schematic side view of an anchor delivery device for use in delivering the anchor devices illustrated inFIGS. 3-5;
• FIG. 7 is a schematic side view of a lead and an alternative anchor device in the form of a coil disposed in a cardiac vein;
• FIG. 8 is a schematic side view of a lead and an alternative anchor device in the form of a bundle disposed in a cardiac vein;
• FIG. 9 is a schematic side view of a lead disposed in a cardiac vein and an alternative anchor device in the form of a plug disposed in a secondary cardiac vein;
• FIGS. 10 and 11 are schematic side views of a lead and alternative anchor devices in the form of wedges disposed in a cardiac vein;
• FIG. 12 is a schematic illustration of a release mechanism in the form of a connector cutter;
• FIG. 13 is a schematic side view of a lead disposed in a cardiac vein and an anchor device in the form of a coiled stent disposed near the ostium of the coronary sinus;
• FIG. 13A is a cross sectional view taken along line A-A inFIG. 13;
• FIG. 13B is side sectional view of the fastener illustrated inFIG. 13;
• FIG. 14 is a schematic side view of a lead disposed in a cardiac vein and an anchor device in the form an anchor catheter; and
• FIG. 15 is a detailed schematic view of the anchor catheter illustrated inFIG. 14.
DETAILED DESCRIPTION OF THE INVENTION
• The following detailed description should be read with reference to the drawings in which similar elements in different drawings are numbered the same. The drawings, which are not necessarily to scale, depict illustrative embodiments and are not intended to limit the scope of the invention.
• With reference toFIGS. 1 and 2, the anatomy of a human heart (H) is illustrated.FIG. 1 shows the heart from the anterior side, with the right chambers of the heart shown in section.FIG. 2 shows the heart from the posterior side, and illustrates the cardiac veins, including the coronary sinus (CS) and its associated venous branches (great cardiac vein, left marginal vein, left posterior ventricular vein, middle cardiac vein, and small cardiac vein). The CS carries the primary venous return for the cardiac circulation, with the venous branches distributed about the heart and draining into the CS. The CS circumnavigates the left side of the heart, generally between the left atrium (LA) and the left ventricle (LV). The CS drains into the right atrium (RA) at the ostium.
• Left ventricular leads are typically implanted with the proximal end connected to a pulse generator in a subcutaneous or submuscular pocket, and the distal end (electrode(s)) disposed in one of the cardiac veins to stimulate the left ventricle. The lead body typically extends from the pulse generator in the subcutaneous or submuscular pocket, through the vein wall and into the left subclavian vein (LSV), through the left brachio-cephalic vein (LBV), down the superior vena cava (SVC) and into the right atrium (RA), into the CS and into the target cardiac vein. The venous circulation is usually accessed by introducing delivery catheters (called guide catheters or guide sheaths) from a venous arteriotomy in the LSV to the CS ostium, following the dashed line shown inFIG. 1. Once the CS is cannulated by a delivery catheter, a coronary venogram is obtained to visualize the cardiac veins. The lead is advanced into the CS and the desired cardiac vein, following an exemplary path indicated by the dashed line shown inFIG. 2.
• There are generally two categories of LV leads, over-the-wire (OTW) leads and stylet-delivered leads. OTW leads incorporate a guide wire lumen which extends through the entire lead body, emerging at the tip of the lead. Navigation within the CS and cardiac veins is performed by advancing a steerable guide wire to a desired location in a cardiac vein, and the lead is then advanced over the guide wire. Stylet delivered leads have a stylet lumen which extends through the lead body, but typically terminates proximal of the distal tip. A shaped styled is positioned in the stylet lumen and the lead and stylet are advanced together to navigate the lead to a desired location in a cardiac vein.
• Once the lead is positioned in a location that yields acceptable stimulation (capture), the delivery catheter is removed. Depending on the particular lead, and the type of electrical connector utilized, removal is accomplished either by withdrawing the delivery catheter over the proximal end of the lead, or by splitting the delivery catheter as it is removed over the proximal end of the lead. In some situations, removal of the delivery catheter may dislodge the lead, as the stability of the lead position is often quite tenuous. Even if the lead is not dislodged during removal of the delivery catheter, the beating of the heart and other patient activities can cause lead movement or dislodgement, leading to potential loss of capture (effective pacing of the LV).
• With reference toFIG. 3, apacing lead10 and an anchor device in the form of astent20 are schematically shown disposed in a cardiac vein CV. Generally, the CV generically refers to venous braches of the coronary sinus such as the great cardiac vein, left posterior ventricular vein, middle cardiac vein, small cardiac vein, or other cardiac vein that leads to the left ventricle, and preferably that leads to the apex of the left ventricular free wall or that otherwise provides for effective pacing of the left ventricle. Those skilled in the art will recognize that because of anatomic variation, the precise name and position of the CV will vary.
• Lead10 may comprises a conventional pacing lead having an elongate body orshaft12 and one ormore electrodes14 connected to a pulse generator (not shown) by corresponding wires or traces inside thelead body12.Lead10 is generally designed to be very flexible and fatigue resistant to permit free cardiac movement, to minimize tissue trauma, and to withstand repeated flexure primarily caused by the beating heart. Theelectrodes14 are typically positioned on or near the wall of the vein facing the heart to establish effective conduction into the heart wall.
• Stent20 may be self-expandable or balloon expandable, for example, and may be formed of a biocompatible metal material such as stainless steel, Nitinol, Elgiloy, or MP35N. Alternatively,stent20 may be formed of a biodegradable polymeric material such as poly-L-lactic acid, polyglycolic acid, or polycaprolactone, or other biodegradable materials such as those used for biodegradable sutures. In the case of polymeric materials used forstent20, the polymer may be loaded with a radiopaque agent such as barium, bismuth subcarbonate, etc. to facilitate x-ray visualization. Generally speaking, all of the anchors of the anchor devices described herein may be formed of the aforementioned materials and may be radiopaque.
• Stent20 may be connected to lead10 by anelongate connector30.Elongate connector30 may comprise a tether that is flexible and fatigue resistant such as a braided cord of a high strength biocompatible polymer such as polyester, polypropylene, or polyethylene (e.g., Spectra brand), and may be partially or fully covered or coated with a material that promotes tissue in-growth such as ePTFE. The tissue in-growth promoting material may serve to secure theelongate member30 to thelead10 and/or prevent bacteria migration along theelongate member30.
• In the embodiment illustrated inFIG. 3, the elongate member ortether30 extends through the lumen (e.g., guide wire lumen) of thelead10. This embodiment is particularly suitable for OTW leads that typically have a guide wire lumen extending therethrough. The proximal end of thetether30 may extend out the proximal end of the lumen of thelead10, and may be connected to thelead10 by tying a knot that is larger than the diameter of the lumen, for example. Alternatively, the proximal end of thetether30 may be connected to the proximal end of thelead10 by trapping thetether30 in the lumen of thelead10 with a wedge or pinching it between the electrical connector of thelead10 and the socket of the pulse generator. The distal end of thetether30 may be connected to thestent20 by tying thetether30 in a knot around a strut of thestent20, or swaging and end of thetether30 between struts of thestent20, for example.
• In this embodiment, thestent20 andtether30 may be deployed before thelead10 is delivered. Thestent20 may be deployed in a distal portion of the target CV with a delivery device as described in more detail with reference toFIG. 6. Once deployed, the proximal end of thetether30 may be inserted into the distal end of the lumen extending through thelead10, and thelead10 may then be advanced over thetether30 and into the CV to the desired position, and pacing tests may be performed to ascertain LV pacing capture. Once thelead10 is in the desired position, the proximal end of thetether30 may be secured to the proximal end of thelead10 as described previously.
• If it is necessary or desired to remove or reposition thelead10, thelead10 may be removed from the CV by disconnecting thetether30 from the lead10 (e.g., by cutting the knot in thetether30 at the proximal end of the lead10), thetether30 may be removed from the CV by disconnecting thetether30 from the stent20 (e.g., by using a cutting device as described in more detail with reference toFIG. 12), and thestent20 may be left in place in the CV without compromising blood flow through the CV.
• With reference toFIG. 4, an alternative anchor device arrangement is shown schematically. In this embodiment, rather than extending through the lumen of thelead10, thetether30 extends along side thelead10. This embodiment is particularly suitable for stylet-delivered leads that typically do not have a lumen extending therethrough, but may be used with either stylet-delivered or OTW leads. This embodiment also allows for the delivery of the anchor device either before or afterlead10 placement.
• Thetether30 may be connected to thelead10 by a fastener such ascollar40.Collar40 may comprise a short dual lumen tube including a relatively large lumen to accommodate thelead10 therethrough and a relatively small lumen to accommodate thetether30 therethrough.Collar40 may be fixedly connected to thelead10 if the anchor device is delivered prior to thelead10 by swaging, adhesive, etc. To facilitate delivery of the lead after placement of thelead10, thecollar40 may be slidable over thelead10 and lock in place adjacent the distal potion of thelead10 using a mating geometry such as a detent on the outer surface of thelead10 that receives a protrusion extending from the inside surface of thecollar40. Alternatively, the outer surface of thelead10 may include a protrusion such as a steppedridge45 that abuts the distal end of thecollar40 as thecollar40 is advanced over thelead10 in order to prevent proximal movement of thelead10 relative to thecollar40. With this alternative, the steppedridge45 may be an integral extension of the outer surface of thelead10 or a separate component fixedly connected to thelead10.
• Thetether30 may be effectively connected to thecollar40 to prevent proximal movement of thecollar40 relative to thetether30 by utilizing a knot or stop35 that is slid down the length of thetether30. A knot may be made in the tether at its proximal end and advanced distally to thecollar40 using a conventional knot pusher. Astop35 may be used and configured to readily advance distally over thetether30 and resist retraction proximally. For example, stop35 may comprise a short tubular segment having proximal facing flanges extending from the inside surface that selectively engage thetether30 only when thestop35 is advanced in the proximal direction relative to thetether30. To facilitate removal of thelead10, thestop35 may be cut or thetether30 may be cut between thestop35 and thecollar40 using the cutting device described with reference toFIG. 12.
• To facilitate advancement of thecollar40 over thelead10 and to facilitate advancement of thestop35 over thetether35, a duallumen advancement sheath50 may be slid (pushed) over thelead10 andtether30.Sheath50 may comprise an elongate dual lumen tube having a length sufficient to extend over thelead10, through the venous vasculature, and out the venous access site, with one lumen to accommodate thelead10 and another lumen to accommodate thetether30.Sheath50 may include a slit (not shown) along the length thereof to facilitate peeling over thelead10.Sheath50 may be removed over thelead10 andtether30 after advancement of thecollar40 and stop35, or it may be left implanted to contain thetether30 relative to thelead10.
• With reference toFIG. 5, an alternative anchor device arrangement is shown schematically. In this embodiment, thestent20 is deployed in a secondary cardiac vein (SCV) and connected viatether30 andcollar40 to lead10 as described with reference toFIG. 4. Positioning thestent20 in a SCV enhances the anchoring effect and, because of collateral venous circulation, reduces the possibility of adverse effects if thestent20 were to become occluded.
• With reference toFIG. 6, a schematic side view of an anchordelivery catheter device100 for use in delivering anchor devices such asstent20 as described in connection with the embodiments ofFIGS. 3-5. In this embodiment, thedelivery device100 is configured to deliver an elastically expandable (self-expanding) stent, but a balloon catheter type delivery device may alternatively be utilized to deliver a plastically deformable (balloon expandable) stent. In the illustrated embodiment, thedelivery catheter100 may include aninner tube110 coaxially disposed in anouter tube120. Thestent20 may be pre-loaded inside theouter tube120, near its distal end. The distal end of theinner tube110 abuts the proximal end of thestent20, and may be advanced distally with respect to theouter tube120 as indicated byarrow115 to advancestent20 out of the distal end of theouter tube120. Thetether30 may be disposed between theinner tube110 and theouter tube120.
• To facilitate delivery, aguide wire130 may be used to initially navigate the CV. Once theguide wire130 is in the desired position, thedelivery catheter100 with thepre-loaded stent20 therein may then be advanced over the proximal end of theguide wire130 and advanced thereover to the desired deployment position. Theinner tube110 may be advanced in the distal direction with respect to theouter tube120 as indicated byarrow115 to deploy thestent20 in the CV. Once thestent20 is deployed, thedelivery catheter100 may be removed.
• With reference toFIG. 7, an alternative anchor device arrangement is shown schematically. In this embodiment, acoil70 is deployed distal of thelead10 and connected viatether30 to lead10 as described with reference toFIG. 3. The proximal end of thecoil70 may be connected to the distal end of thetether30 atconnection75, and thecoil70 may comprise a resilient structure such as a metal wire formed of any of the materials described with reference tostent20.Coil70 may be delivered via a lumen (e.g. guide wire lumen) extending through thelead10 and is particularly suitable for an OTW lead. Thecoil70 may be advanced through the lumen of thelead10 using a push tube (not shown) having sufficient column strength disposed over thetether30 that abuts theconnection75 between thecoil70 and thetether30.
• To accommodate delivery through the lumen extending through thelead10, thecoil70 may have a delivery configuration wherein thecoil70 is elongated to have a reduced profile sufficiently small to fit into the lumen, and a deployed configuration wherein thecoil70 is radially expanded to have an expanded profile sufficiently large to frictionally engage the wall of the CV. Thecoil70 may be highly elastic such that it assumes the deployed configuration automatically upon advancement out of the distal end of thelead10, or the coil may be actuated (e.g., thermally) upon advancement out of the distal end of thelead10 to assume the deployed configuration.
• With reference toFIG. 8, an alternative anchor device arrangement is shown schematically. In this embodiment, abundle80 is deployed distal of thelead10 and connected viatether30 to lead10 as described with reference toFIG. 3. The proximal end of thebundle80 may be connected to the distal end of thetether30 atconnection85, and thebundle80 may comprise a resilient structure such as a metal wire formed of any of the materials described with reference tostent20.Bundle80 may be delivered in the same manner as and may have the same or similar characteristics ascoil70 described with reference toFIG. 7.Bundle80, as opposed tocoil70, may have an occlusive effect, and therefore may be particularly suitable for a SCV to take advantage of collateral venous circulation.
• With reference toFIG. 9, an alternative anchor device arrangement is shown schematically. This embodiment is similar to the embodiment illustrated inFIG. 5, except that aplug90 is used in place ofstent20. Theplug90 may comprise a curable adhesive (e.g., cyanoacrylate, EVA in a DSMO solvent) or an embolic coil, for example, such as those conventionally used in occluding blood vessels and aneurisms.Plug90 may be deployed in a SCV using a conventional embolic delivery system and connected viatether30 andcollar40 to lead10 as described with reference toFIG. 4. Positioning theplug90 in a SCV enhances the anchoring effect, and despite the occlusive effect of theplug90, the possibility of adverse effects are reduced if not eliminated due to collateral venous circulation.
• With reference toFIGS. 10 and 11, alternative anchor device arrangements are shown schematically. In these embodiments, awedge140 or150 is deployed adjacent the distal portion of thelead10, such as proximal ofelectrodes14.Wedges140 and150 frictionally engage thelead body12 and the wall of the CV, to lodge thelead10 in the desired position in the CV. Thewedges140 and150 may be connected to tether30 to facilitate subsequent removal.Wedges140 and150 may comprise any of the materials discussed with reference tostent20.Wedges140 and150 are particularly suitable for deployment after thelead10 has been delivered to the desired position.
• With specific reference toFIG. 10,wedge140 includes abody portion142 andoptional threads144.Body portion142 may include a perfusion lumen extending therethrough to permit blood perfusion from the distal end to the proximal end of thewedge140. The wedge body142 (or thewedge threads144 if used) may have a diameter slightly greater than the diameter of the lumen of the CV less the diameter of thelead10 in order to provide a snug frictional fit therebetween.Wedge140 may be delivered into the desired position utilizing apush tube60 advanced over a guide wire (not shown), for example, wherein thepush tube60 has sufficient column strength to push thewedge140 alongside thelead10 with thedistal end65 of the push tube abutting the proximal end of thewedge140 and thetether30 extending through the push tube. The push tube may also have sufficient torsional strength with adistal end65 that mates with the proximal inside diameter of thewedge140 such that thewedge140 may be rotated to engage or disengage thethreads144 with thelead10 and the wall of the CV.
• With specific reference toFIG. 11,wedge150 comprises a short dual lumen having one lumen to accommodate thelead10 and another (crescent shaped) lumen to permit blood perfusion from the distal end to the proximal end of thewedge150. Thewedge150 may be tapered and may have a diameter slightly greater than the diameter of the lumen of the CV less the diameter of thelead10 in order to provide a snug frictional fit therebetween. Steppedridge45 prevents proximal movement of thelead10 relative to wedge150 as described previously.Wedge150 may be delivered into the desired position utilizing apush tube50 advanced over thelead10, as described previously.
• With reference toFIG. 12, acutting device160 is shown schematically. Cuttingdevice160 may be used to cuttether30 and/or stop35 in order to disconnect thetether30 from the anchor device, such asstent20. Cuttingdevice160 is merely an example of a variety of cutting mechanisms that may be used to sever the connection of thetether30 from the anchor device. For example, thetether30 may be equipped with two internal wires connected to a distal electrolytic fuse that separates (melts) upon the application of electrical current, such as those used for detachable embolic coils.
• In this exemplary embodiment, cuttingdevice160 includes anouter tube162 and aninner tube164 coaxially disposed and movable therein. The outer andinner tubes162 and164 may have a length sufficient to extend from outside the vascular access site to the anchor device, and may be configured for intravascular navigation and advancement overtether30. The distal end of theinner tube164 may have a sharpened edge and may be formed of a material that retains a cutting edge (e.g., metal). A cuttinghole168 is provided adjacent the distal end of theouter tube162 through which thetether30 may be threaded. The distal circumference of thecutting hole168 may be sharpened and may be formed of a material that retains a cutting edge (e.g., metal) After the cutting device is advanced over thetether30 to the desired cutting site, theinner tube164 may be advanced distally as indicated byarrow166, with the sharpened distal end of theinner tube164 and the sharpenedcutting hole168 acting as shears to cut thetether30 at thecutting hole168.
• With reference toFIG. 13, alead10 is shown disposed in a CV, with an anchor device in the form of acoiled stent200 disposed near the ostium of the CS. Thecoiled stent200 may be positioned near the ostium of the CS, where the vessel diameter is large enough to resist becoming occluded by the presence of thecoiled stent200 next to thelead10. However, it is contemplated that thecoiled stent200 may be placed elsewhere within the CS or CV in which the lead is positioned. As seen inFIG. 13A, thelead10 is eccentrically disposed in the lumen of the CS to define a relatively large crescent shaped blood perfusion lumen.
• Coil stent200 may be formed of a resilient material such as Nitinol, Elgiloy, MP35N, or stainless steel.Coiled stent200 could also be formed of degradable materials such as those described in reference tostent20 above.Coiled stent200 may be releasably attached to thelead10 utilizingcollar210, andcollar210 may frictionally engage thebody12 oflead10, thus facilitating anchoring of the lead within the coronary sinus or cardiac vein.
• With reference toFIG. 13B, thecollar210 may comprise a relativelyshort tube212, and may include one or more proximally oriented grips218.Grips218 may be in the shape of finger-like projections, or circular ribs either partially or completely extending circumferentially around the inside oftube212.Grips218 facilitate the advancement of thecollar210 in a distal direction for delivery overlead10, but resist proximal movement once thecollar210 is positioned in a desired anchoring location.Grips218 may be formed of a soft resilient material such as silicone, polyurethane, polyether-block-amide, or the like.
• To facilitate subsequent removal of thelead10, thecoiled stent200 may be connected to thecollar210 in a detachable manner. For example, thecoiled stent200 may be connected to thecollar210 utilizing a biodegradable adhesive connecting adjacent portions of thecoil200 to thecollar210. Such an adhesive may degrade after thelead10 has chronically anchored to the wall of the CS by normal tissue encapsulation. After the adhesive has degraded, the lead10 (along with collar210) may be removed utilizing standard techniques, with thecoiled stent200 remaining in the CS.
• Alternatively, thecoiled stent200 may be secured to thecollar210 utilizing aretractable pin220. In this alternative embodiment,collar210 may include twoangled flanges214 collectively defining arecess216 in whichstent coil200 may reside.Pin220 may span the length of therecess216 between theflanges214, extending over thecoiled stent200 to retain thecoil stent200 in therecess216, thus providing a connection between thestent coil200 and thecollar214. Subsequent release of thestent coil200 from thelead10 may be accomplished by removingpin220 usingtether30 which extends from the proximal end of thelead10 to thepin220. The proximal end of thepin220 is connected to the distal end of thetether30, and thepin220 may be removed by pulling thetether30 proximally. After thepin220 is removed, thelead10 andcollar210 are free from thestent coil200 and may be removed with standard techniques, leavingstent coil200 in the CS.
• Delivery and deployment of thestent coil200 andcollar210 may be facilitated bydeployment sheath230. Thedeployment sheath230 may comprise a tubular catheter, having a lumen extending therethrough to accommodate thelead10 and thestent coil200. Alternatively, the lumen in thedeployment sheath230 may extend from a distal opening to a mid-shaft opening as used in conventional monorail style balloon catheters. Afterlead10 has been positioned by standard techniques to a desired position, thestent coil200 andcollar210 may be loaded on the proximal end of thelead10.Coil200 may be initially in a compressed condition, and loaded in the inside of thedeployment sheath230. If thelead10 has a large diameter proximal connector, anoptional slit215 may be provided in thecollar220 to facilitate loading over the large diameter connector. In this case, thecollar210 andcoil200 may be positioned on thelead body12 before thecoil200 is loaded into thedeployment sheath230. Thedeployment sheath230 may be advanced distally down thebody12 of thelead10 until thestent coil200 andcollar210 are in the desirable location. Thedeployment sheath230 may then be withdrawn proximally, with thecollar210 andstent coil200 remaining in position on thelead10 due togrips218 oncollar210. As thestent coil200 emerges from thedeployment sheath230, it expands to engage the wall of the CS. Thedeployment sheath230 can then be removed from thelead10.
• FIGS. 14 and 15 illustrate an anchor device in the form of an anchoringcatheter300, which may be utilized to secure the position oflead10, particularly during the removal of the guide sheath (guide catheter) used in the delivery of thelead10. As described above, the lead stability is particularly vulnerable during the removal of the guide sheath.
• In use, the anchoringcatheter300 is positioned next to thelead10 afterlead10 has been positioned in a desired location. Anchoringcatheter300 may be advanced within the guide sheath (not shown), generally parallel to thelead body12, or may be advanced outside the guide sheath. An expandable member such as aballoon314 is inflated to frictionallysecure lead10 against the wall of the blood vessel. The guide sheath can then be removed without inadvertent dislodgement of thelead10. The anchoringcatheter300 can then be removed. Since anchoringcatheter300 is next to and not surrounding thelead body12, removal of the anchoringcatheter300 does not pose a risk of dislodginglead10.
• With particular reference toFIG. 15, anchoringcatheter300 is shown in more detail.Shaft312 may comprise aproximal shaft portion312A connected by adhesive, for example, to adistal shaft portion312B. Aluer adaptor316 may be connected to the proximal end of theproximal shaft portion312A for connection to an inflation apparatus (not shown) such as a syringe. Aninflatable balloon314 may be connected to the distal end of thedistal shaft portion312B, and may be formed of elastomeric material or a molded inelastic material.
• Proximal shaft portion312A may be relatively stiff and may be formed of a metallic tube such as a stainless steel hypotube.Distal shaft portion312B may be relatively flexible and may be formed of a polymeric tube, for example. To facilitate advancement of the flexibledistal shaft portion312B and theballoon314, a core wire may be connected to and extend from the distal end of theproximal shaft portion312A. Thecore wire320 may comprise a metal wire such as a tapered stainless steel mandrel.
• Core wire320 extends to the distal end of theballoon314, and may extend beyond with an atraumatic spring tip, for example. The distal end of theballoon314 may be bonded to thecore wire320, and the proximal end of theballoon314 may be bonded to the distal end of thedistal shaft portion312B. Within theshaft312 is a lumen through which inflation medium is infused to inflateballoon314.
• Those skilled in the art will recognize that the present invention may be manifested in a variety of forms other than the specific embodiments described and contemplated herein. Accordingly, departures in form and detail may be made without departing from the scope and spirit of the present invention as described in the appended claims.

Claims (19)

1-28. (canceled)

29. A system for stabilizing an electrical lead in a coronary vessel, comprising:

an electrical lead having a proximal portion and a distal portion with a lumen extending therethrough; and

an intravascular anchoring device including an anchor and an elongate tether, the tether detachably connected to the anchor and extending proximally from the anchor, the tether extending through the lumen of the lead with the anchor disposed distally of the lead, wherein the lead is longitudinally movable with respect to the anchoring device.

30. A system as inclaim 29, further comprising a connector for limiting longitudinal movement between the lead and the anchoring device, wherein the connector is insertable into the lumen of the lead adjacent the tether.

31. A system as inclaim 29, wherein the tether in nonelectrically conductive.

32. A system as inclaim 29, wherein the tether comprises a braid.

33. A system as inclaim 29, wherein the tether comprises a polymeric braid.

34. A system as inclaim 29, wherein the anchor comprises a self-expanding structure.

35. A system for stabilizing an electrical lead in a coronary vessel, comprising:

an electrical lead having a proximal portion and a distal portion with a lumen extending therethrough; and

an intravascular anchoring device including a self-expanding anchor and an elongate tether, the tether connected to the anchor and extending proximally from the anchor, the tether extending through the lumen of the lead with the anchor disposed distally of the lead, wherein the lead is longitudinally movable with respect to the anchoring device.

36. A system as inclaim 35, further comprising a connector for limiting longitudinal movement between the lead and the anchoring device, wherein the connector is insertable into the lumen of the lead adjacent the tether.

37. A system as inclaim 35, wherein the tether in non-electrically conductive.

38. A system as inclaim 35, wherein the tether comprises a braid.

39. A system as inclaim 35, wherein the tether comprises a polymeric braid.

40. A system as inclaim 35, wherein the tether is detachable from the anchor.

41. A system for stabilizing an electrical lead in a coronary vessel, comprising:

an electrical lead having a proximal portion and a distal portion with a lumen extending therethrough; and

an intravascular anchoring device including an anchor and an elongate non-electrically conductive tether, the tether connected to the anchor and extending proximally from the anchor, the tether extending through the lumen of the lead with the anchor disposed distally of the lead, wherein the connector is insertable into the lumen of the lead adjacent the tether.

42. A system as inclaim 41, further comprising a connector for limiting longitudinal movement between the lead and the anchoring device, wherein the connector is insertable into the lumen of the lead adjacent the tether.

43. A system as inclaim 41, wherein the anchor comprises a self-expanding structure.

44. A system as inclaim 41, wherein the tether comprises a braid.

45. A system as inclaim 41, wherein the tether comprises a polymeric braid.

46. A system as inclaim 41, wherein the tether is detachable from the anchor.

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