Abstract:
A medical stylet for guiding a lead includes a first elongate member for attachment of the lead to the target tissue, a second elongate member to reshape the lead. The first elongate member of the medical stylet includes a proximal end portion, and a distal end portion wherein the distal end portion of the first elongate member includes a tip feature configured to engage the lead on application of torque externally. The second elongate member defines a lumen along its length. The lumen of the second elongate member can be configured to enclose at least a portion of the first elongate member. The second elongate member can have a pre defined shape. The pre defined shape of the second elongate member allows the lead to be reshaped when inserted into the lead, this reshaped lead now can be guided to an anatomical pass way.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority to U.S. Provisional Application No. 61/693,418, filed Aug. 27, 2012, which is herein incorporated by reference in its entirety. 
     
    
     TECHNICAL FIELD 
       [0002]    The present disclosure relates to a medical stylet. More specifically, the invention relates to a pre-shaped stylet for implanting a lead in the heart of a patient and for delivering torque to a distal lead feature. 
       BACKGROUND 
       [0003]    Implantable medical leads can be used to deliver electrical stimulation to the body tissue through implantable medical devices. Exemplary implantable devices include cardiac rhythm management (CRM) systems (e.g., pacemakers, defibrillators, and cardiac resynchronization therapy devices) and neurostimulation systems (e.g., spinal cord stimulation (SCS) systems). For CRM systems, the medical leads typically extend intravascularly to an implant location within or on a patient&#39;s heart. The implantable medical leads can be equipped with at least one electrode. The implantable medical leads are often positioned so that the electrode delivers electrical stimulation to a target tissue without stimulating adjacent tissue. The implantable medical leads can be flexible and can require use of a support device (e.g., a stylet) to effectively guide the implantable medical lead into a desired location inside the heart of a patient. A stylet-driven implantable medical lead can have a pre-formed shape to facilitate advancement of the medical lead to certain locations within the heart. 
         [0004]    Implantable medical leads are often anchored or fixed to heart tissue using an active (i.e., movable or deployable) fixation anchor, such as a rotatable helix, located at or near a distal end of the lead. As the medical leads are typically flexible in torsion, it can be a challenge to use the lead body to rotate the helix. For stylet-driven implantable medical leads, the stylet can operate to deliver torque from a proximal end of the lead to an active fixation mechanism at or near the distal end of the lead. 
       SUMMARY 
       [0005]    Example 1 is a medical stylet for use in delivering and anchoring an implantable medical lead to a desired location near or in a patient&#39;s heart. The stylet includes an inner member, having a distal end portion and a proximal end portion, wherein the distal end portion includes a tip feature configured to rotationally engage a coupling feature at or near a distal end of the implantable medical lead. The coupling feature is rotationally coupled to an anchoring mechanism including a fixation feature. The stylet further includes an outer member defining a lumen along its length, the lumen configured to accept and allow rotation of at least a portion of inner member. The outer member has a predetermined shape and sufficient stiffness to impart the shape upon the lead. The shape is selected to assist in delivery of the lead to the desired implant location. The inner member has sufficient torsional stiffness to transmit a torque from the proximal end portion to the coupling feature, so as to rotate the anchoring mechanism. 
         [0006]    Example 2 is the medical stylet of Example 1, further comprising an actuating mechanism and wherein the proximal end portion of the inner member is configured to be rotated by the actuating mechanism. 
         [0007]    Example 3 is the medical stylet of Example 1 or 2, wherein the tip feature is configured to be manipulated by the actuating mechanism to engage with the coupling feature of the implantable medical lead. 
         [0008]    Example 4 is the medical stylet of any of Examples 1-3, wherein the inner member is made from at least one of steel, titanium, nickel, and a polymer. 
         [0009]    Example 5 is the medical stylet of any of Examples 1-4, wherein the tip feature of the inner member defines a non-circular shape. 
         [0010]    Example 6 is the medical stylet of any of Examples 1-5, wherein the predetermined shape of the outer member is a J-shape and the desired location in an atrium of the heart. 
         [0011]    Example 7 is the medical stylet of any of Examples 1-6, wherein the predetermined shape of the outer member is an L-shape and the desired location is a His bundle of the heart. 
         [0012]    Example 8 is the medical stylet of any of Examples 1-7, wherein the predetermined shape is a multi-planar shape. 
         [0013]    Example 9 is the medical stylet of any of Examples 1-8, wherein the outer member is made from at least one of a stainless steel and a nickel-cobalt alloy. 
         [0014]    Example 10 is the medical stylet of any of Examples 1-9, wherein the inner member has a torsional stiffness sufficient to deliver a torque to the coupling feature, with less than 360 degrees rotation along its length, in an amount between about 20 and about 100 micronewton-meters. 
         [0015]    Example 11 is a cardiac lead assembly including an implantable medical lead having a lead body having a lead proximal end and a lead distal end and a lead lumen extending therethrough. The lead further including an anchoring mechanism disposed at or near the lead distal end, the anchoring mechanism having a coupling feature and a fixation feature. The assembly includes a stylet for use in guiding the implantable lead to a desired implant site. The stylet includes an inner member, having a distal end portion and a proximal end portion, wherein the distal end portion includes a tip feature. The tip feature is configured to rotationally engage the coupling feature at or near the distal end of the implantable medical lead. The stylet further includes an outer member defining a stylet lumen along its length, the stylet lumen configured to accept and allow rotation of at least a portion of inner member. The outer member has a predetermined shape and sufficient stiffness to at least partially impart the shape upon the lead. The shape is selected to assist in delivery of the desired implant site. The inner member has sufficient torsional stiffness to transmit a torque from the proximal end portion to the coupling feature, so as to rotate the anchoring mechanism. 
         [0016]    Example 12 is the cardiac lead assembly of Example 11, wherein the inner member is made from at least one of steel, titanium, nickel, and a polymer. 
         [0017]    Example 13 is the cardiac lead assembly of Example 11 or 12, wherein the tip feature of the inner member defines a non-circular shape. 
         [0018]    Example 14 is the cardiac lead assembly of any of Examples 11-13, wherein the anchoring mechanism includes a helix configured for engaging and anchoring with tissue in or near a patient&#39;s heart. 
         [0019]    Example 15 is the cardiac lead assembly of any of Examples 11-14, wherein the predetermined shape is a multi-planar shape. 
         [0020]    Example 16 is the cardiac lead assembly of any of Examples 11-15, wherein the outer member is made from at least one of a stainless steel and a nickel-cobalt alloy. 
         [0021]    Example 17 is the cardiac lead assembly of any of Examples 11-16, wherein the inner member has a torsional stiffness sufficient to deliver a torque to the coupling feature, with less than 360 degrees rotation along its length, in an amount between about 20 and about 100 micronewton-meters. 
         [0022]    Example 18 is the cardiac lead assembly of any of Examples 11-17, wherein the fixation feature is a fixation helix. 
         [0023]    Example 19 is a method of placing a lead in an anatomical location, using a medical stylet. The method includes inserting the medical stylet into a lumen defined by the lead, the medical stylet including an inner member, and an outer member at least partially surrounding the inner member, the outer member configured for providing a shape to the lead in accordance with an anatomical passageway, wherein the lead includes an anchoring mechanism having a coupling feature. The method further includes guiding the stylet along the anatomical passageway to the anatomical location. The method further includes rotating the medical stylet so as to cause the inner member to impart torque upon the coupling feature thereby causing the anchoring mechanism to rotate and engage tissue to anchor the lead at the anatomical location. 
         [0024]    Example 20 is the method of Example 19, further comprising retracting the medical stylet after anchoring the lead at the anatomical location. 
         [0025]    While multiple embodiments are disclosed, still other embodiments of the present disclosure will become apparent to those skilled in the art from the following detailed description, which describes and depicts illustrative embodiments of the invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0026]      FIG. 1  is a perspective view of an implantable medical device in a cardiac rhythm management (CRM) system, according to various embodiments. 
           [0027]      FIGS. 2A-2C  show views of a medical stylet, according to various embodiments. 
           [0028]      FIG. 3A  is a schematic diagram illustrating a distal portion of an implantable medical lead. 
           [0029]      FIG. 3B  is a schematic diagram illustrating a medical stylet engagement to a coupler of a lead 
           [0030]      FIG. 4A  is a front view of a tip portion attached to a distal end of a first elongate member and a proximal end of a first elongate member enclosed within a second elongate member. 
           [0031]      FIG. 4B  is a perspective view of a tip portion with a distal end portion and a proximal end portion of a first elongate member. 
           [0032]      FIG. 5  is a perspective view of a J-shaped stylet placing a lead in an atrium of a heart, according to various embodiments. 
           [0033]      FIG. 6  is a flowchart illustrating a method of placing of a lead in the heart using a stylet. 
       
    
    
       [0034]    While the invention is amenable to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and are described in detail below. The intention, however, is not to limit the invention to the particular embodiments described. On the contrary, the invention is intended to cover all modifications, equivalents, and alternatives falling within the scope of the invention as defined by the appended claims. 
       DETAILED DESCRIPTION 
       [0035]      FIG. 1  is a perspective view of an implantable cardiac rhythm management (CRM) system  10 . As shown, the system  10  includes an implantable rhythm management device  12  and an implantable lead  14 , which extends from a proximal end portion  18  to a distal end portion  20 . As shown in  FIG. 1 , the heart  16  includes a right atrium  26 , a right ventricle  28 , a left atrium  30 , and a left ventricle  32 . As further shown, the heart  16  includes an endocardium  34  covering the myocardium  36 . As shown, an anchoring mechanism (e.g., a fixation helix)  24  located at the distal end portion  20  of the lead  14  penetrates through the endocardium  34  and is embedded in the myocardium  36 . In some embodiments, the anchoring mechanism  24  is electrically active and thus, operates as a helical electrode for sensing the electrical activity of the heart  16  and/or applying a stimulating pulse to the right ventricle  28 . In various embodiments, the anchoring mechanism  24  includes a coupling feature for coupling with a stylet and a fixation feature for engaging and anchoring with tissue in or near the heart  16 . In various embodiments, the CRM system  10  includes a plurality of leads similar to the lead  14 . For example, it can include a first lead that can be similar to the lead  14  adapted to convey electrical signals between the pulse generator (which can be the implantable rhythm management device)  12  and the right ventricle  28  and a second lead (not shown) adapted to convey electrical signals between the pulse generator  12  and the right atrium  26  or coronary veins (not shown). 
         [0036]      FIGS. 2A-2C  show various view and portions of a stylet  300  for assisting with delivery of the lead  14  to a desired location within or near the patient&#39;s heart. As shown in  FIG. 2A , the stylet  300  includes an inner elongate member  302 , an outer elongate member  304 , and an actuating mechanism  326 . The inner member  302  and outer member  304  are sized and shaped such that the inner member  302  can be disposed within the outer member  304 , in such a manner that the inner member  302  can be translated and rotated within the outer member  304 . This translation and rotation can be accomplished by the actuating mechanism  326  in various embodiments. In other embodiments, the stylet  300  does not include an actuation mechanism  326 . In these embodiments, this translation and rotation can be accomplished directly by a user (e.g., a physician) manipulating one or both of the inner member  302  and the outer member  304 . 
         [0037]    As further shown in  FIG. 2A , the stylet  300  has a length defined by the length of the inner member  302 , which has a length greater than a corresponding length of the outer member  304 . As shown, the length of the inner member  302  exceeds the length of the outer member  304  by a distance “D.” The inner member  302  includes a distal tip portion  306 , which extends beyond a distal portion  312  of the outer member  304 . In exemplary embodiments, the length of the medical stylet  300  is selected based on a corresponding length of the lead  14  that the stylet will be used to help implant. For example, the stylet  300  can have a sufficient length to extend from proximal to a lead proximal end to a location at or near a distal end of the lead. In various embodiments, the length of the stylet  300  is between about 400 mm and about 600 mm. More specifically, in certain embodiments, the length of the stylet  300  is one of 450 mm, 520 mm, 580 mm, and 590 mm. In various embodiments, the distance “D” is between about 1 mm and about 20 mm. According to various embodiments, the inner member  302  has an outer diameter of between about 0.0040 inches and 0.0100 inches, and the outer member  304  has an outer diameter of between about 0.0050 inches and about 0.0250 inches. In some embodiments, the outer diameter of the inner member  302  is 0.0080 inches, and the outer diameter of the outer member  304  is 0.017 inches. 
         [0038]    In some embodiments, the implantable lead  14  including a silicone lead body, which is generally flexible and not configured to have a predetermined shape. The implantable lead  14  can be configured for placement in a variety of locations in or near the heart  16 , including the atrial wall, the ventricular wall, the septal wall, or a location at or near the bundle of His (located at or near the atrioventricular node). To assist in delivering the implantable lead  14  through the patient&#39;s vascular system and to a desired location in or near the heart (such as those described above), it is helpful to have a mechanism to impart a desired shape or curvature upon the lead body. As the lead body is often made from a soft, silicone material, one such mechanism is through the use of a stylet  300  having a preset or predetermined shape. Upon placing such a stylet within a lumen of the implantable lead, the lead will conform to the shape of the stylet  300 . As shown in  FIG. 2A , for example, the stylet  300  is preformed, as further explained below, with a curved distal portion  320  having a radius of curvature  322 . 
         [0039]    The outer member  304  includes an inner lumen extending along its length. The lumen is sized to accept the inner member  302  to form the stylet  300 . In various embodiments, the outer member  304  of the medical stylet  300  is formed of sufficiently stiff material to allow the outer member  304  to hold a predetermined shape. In various embodiments, the outer member  304  is made from one or more of a steel, steel alloy (including, for example, stainless steel) titanium, titanium alloys, nickel, nickel alloy, nickel-titanium alloy (including, for example, Nitinol and MP35N), or a polymer (e.g., PEEK or polyamide). In some embodiments, the outer member  304  is made from a stainless steel or a nickel cobalt alloy. In various embodiments, the second elongate member  304  is configured to have a predefined J-shape, wherein the J-shape is selected to allow the lead  14  to be placed at a desired location in or near the heart  16 . As shown in  FIG. 3B , the outer member  304  has a distal curved portion having a radius of curvature  322  of between about 0.40 and 0.50 inches. This radius of curvature can be selected to direct a distal portion of the implantable lead  14  to a desired location in the atrium. In other embodiments, the curved portion is configured with a predetermined wider curve, or with an L-shape, for example to assist in directing a distal portion of the implantable lead to a location near the bundle of His. 
         [0040]    As shown in  FIGS. 2B-2C , the inner member  302  of the stylet  300  includes a distal tip portion  306 , which is configured to engage with a portion of the implantable lead  14 . By engaging appropriately with a distal portion of the implantable lead, the stylet can operate to transmit a torque from a proximal end of the stylet to a component of the implantable lead. In some embodiments, the inner member  302  can be configured to be substantially straight along its length and to have a substantially circular cross-section. The substantially straight shape of the first elongate member  302  facilitates delivery of torque along its length and ultimately to a component of the lead  14  to which it is rotationally coupled. The inner member  302  is made of a material having torsional stiffness. According to various embodiments, the inner member  302  is made from one or more of a steel, steel alloy (including, for example, stainless steel) titanium, titanium alloys, nickel, nickel alloy, nickel-titanium alloy (including, for example, Nitinol and MP35N), or a polymer (e.g., PEEK or polyamide). In some embodiments, the distal tip portion  306  of the inner member  302  is formed of a polymer and the remaining length is formed of stainless steel or Nitinol. In other embodiments, the distal tip portion  306  is formed of a metal and the remaining length of the inner member  302  is formed of a polymer. The inner member  302  may be formed as a tube, a wire, a cable, a coil, or any combination of these elements. 
         [0041]      FIG. 2B  is a perspective view of the tip portion  306  of the inner member  302  extending from the proximal portion  312  of the second elongate member  304 . As shown, the tip portion  306  includes a tip feature  310 . This feature  310  can function to both facilitate engagement with a corresponding lead feature and to transfer torque from the inner member  302  to a corresponding lead feature. The tip feature  310  can be any shape capable of engaging with a corresponding shape on a lead feature, including, for example, a flat face, a triangular sectional shape, a square sectional shape, a star sectional shape, a hex sectional shape, a star shape (e.g., a Torx® profile), or other custom shape capable of transferring torque. The specific dimensions of the feature  310  are selected to provide a close (e.g., interference) fit with a corresponding feature on the component of the lead  14 . 
         [0042]      FIG. 2C  shows an exemplary tip portion  306  of the inner member  302  of the medical stylet  300 . As shown, the tip portion  306  includes a proximal portion  328  and a distal portion  330 . The tip portion  306  can include a length  340  extending from the proximal portion  328  to the distal portion  330 . The length  340  can vary from 0.04 inch to 0.08 inch. In some embodiments, the length  340  can be 0.06 inch. The tip portion  306  can be configured to include a first swage point  338  along a plane  344 . The first swage point  338  can be defined and configured so that the proximal portion  328  forms a first swage angle  350  (α) with the distal portion  330 . The first swage point  338  can be the point where the proximal portion  328  meets the distal portion  330 . The proximal portion  328  can be configured to be substantially straight. The tip portion  306  can be configured to define a second swage point  348  along a plane  346 . The second swage point  348  can be defined and configured so that the proximal portion  328  forms a second swage angle  352  (β) with the distal portion  330 . The second swage point  348  can define the point where the tip portion  306  meets other components of the first elongate member  302 . 
         [0043]    In various embodiments, the tip portion  306  can be configured so that the first swage angle  350  (α) can be substantially opposite to the second swage angle  352  (β). The first swage point  338 , the first swage angle  350  (α), the second swage point  348 , or the second swage angle  352  (β) can be positioned or configured so as to allow various shapes to be designed for the tip portion  306  such as to facilitate fixation of the tip portion  306  to the coupler  356  of the lead  14  for lead torque delivery or lead implantation. In an embodiment, the tip feature  310  can be configured to have one of bladed, triangular cut, square cut, Philips, Torx®, hex, or any other custom keyed head for easy fixation with the coupler  356  placed inside the lead  14 . The distal portion  330  of the tip portion  306  can be configured to define a width  342 . The width  342  can be configured so that it decreases along the direction A1 starting from the first swage point  338  or the second swage point  348 , and extending until an end point  354  located on the distal portion  330 . In an embodiment, the width  342  can vary between 0.005 inch and 0.009 inch. In an embodiment, the width  342  can be 0.007 inches at end point  354 . 
         [0044]      FIG. 3A  is a sectional view of components of an anchoring mechanism (e.g., a fixation helix)  24  of an implantable medical lead  14 . As described above, the anchoring mechanism  24  is typically coupled at or near a distal end of the medical lead  14 , and it operates to help anchor or secure the lead  14  at a desired location in or near the patient&#39;s heart. As shown, the anchoring mechanism  24  includes a housing  402  and a rotatable helical member (i.e., fixation feature)  406 . The housing  402  and helical member  406  are configured such that upon rotation of the helical member, it will advance forward such that it extends from a distal end or the housing  402 . In this way, the helical member  406  may extend into and engage tissue to perform an anchoring function. In some embodiments, the housing  402  is active such that it operates as an electrode. In some embodiments, an internal surface of the housing  402  is lined with a polymer liner  407  to prevent electrical communication between the housing and the helical member. In some embodiments, the housing  402  further includes a peg, which holds the helical member  406  in place and allows the helical member  406  to extend from the housing  402  only upon rotation. The helical member  406  includes a structure  410  having coupling feature  418 . The coupling feature  418 , according to various embodiments, is configured to couple with the tip feature  310  of the inner member  302  in such a manner as to allow torque to transfer from the inner member  302  to the coupling feature  418 . This torque will then operate to encourage rotation of the helical member  406 .  FIG. 3B  shows the tip portion  306  of the inner member  302  extending from a distal portion of the outer member  304 , according to other embodiments. In  FIG. 3B , the distal tip feature  310  (not shown) is coupled or mated with the coupling feature  418  of the implantable lead  14 . In this configuration, the stylet  300  can be used to deliver torque to the lead feature by rotating the inner member  302 . 
         [0045]    According to various embodiments, the inner member  302  is configured to have a torsional stiffness sufficient to deliver a torque input at the proximal end, along its length to the distal end to the anchoring mechanism (e.g., fixation helix)  24 , with less than 360 degrees rotation (i.e., twisting) along the length of the inner member  302  (i.e., between the proximal end and the distal end). In particular, according to various embodiments, the inner member  302  has a torsional stiffness sufficient to deliver a torque to the fixation helix, with less than 360 degrees rotation along its length, in an amount in the range between about 10 and about 250 micronewton-meters. In other embodiments, the inner member  302  has a torsional stiffness sufficient to deliver a torque to the fixation helix with less than 360 degrees rotation along its length, in an amount in the range between about 20 and about 100 micronewton-meters. In further embodiments, the inner member  302  has a torsional stiffness sufficient to deliver a torque to the fixation helix, with less than 360 degrees rotation along its length, in an amount in the range between about 30 and about 80 micronewton-meters. In further embodiments, the inner member  302  has a torsional stiffness sufficient to deliver a torque to the fixation helix, with less than 360 degrees rotation along its length, in an amount of at least about 40 micronewton-meters. According to various embodiments, the inner member  302  has sufficient torsional stiffness to deliver a torque to the fixation helix, with less than 24 degrees or rotation along its length, in any of the various amounts set forth above. 
         [0046]      FIGS. 4A and 4B  show further embodiments of a stylet  300 . As shown, the distal end portion  306  of the inner member  302  has a diameter larger than an inner diameter of the outer member  304 . By having an enlarged diameter, the end portion  306  is prevented from moving longitudinally into the lumen of the outer member  304 . In this manner, the inner member  302  is restricted from moving longitudinally with respect to the outer member  304 , but remains free to rotate with respect to the outer member  304 . 
         [0047]    In embodiments of a stylet  300  including an actuating mechanism  326  (as shown, for example, in  FIG. 2A ), the mechanism can be operated to provide relative longitudinal and/or rotational movement between the inner member  302  and the outer member  304 . In various embodiments, the mechanism  326  is configured to advance the inner member  302  with respect to the outer member  304 , so as to engage with the lead  14 . The actuating mechanism  326  can be configured to actuate and move the inner member  302  back and forth within the lumen  316  of the outer member  304 , for example, toward the coupling feature  418  of the lead  14 . The actuating mechanism  326  can further be configured to retract the inner member  302  back into the lumen  316  after implant of the lead  14  at the desired implant location. In some embodiments, the actuating mechanism  326  is coupled at the proximal end portion of the outer member  304 . In other embodiments, the actuating mechanism  326  is operatively coupled to the inner member  302 . In various embodiments, the actuating mechanism  326  can be a handle or a knob wherein rotating the handle or the knob can cause the inner member  302  to rotate and engage with the coupling feature  418  of the lead  14 . In some embodiments, the actuating mechanism  326  can be a push button or a piston type arrangement that allows the movement of the inner member  302  forward and backward in order to engage with the lead  14 . 
         [0048]    During use, the stylet  300  can be inserted into the longitudinally extending lumen of the lead  14 . The stylet  300  can be inserted such that the distal tip feature  310  engages the coupling feature  418  at or near a distal end of the lead  14 . Upon insertion into the lead  14 , the outer member  304  of the stylet  300  imparts (wholly or partially) its predetermined shape onto the flexible lead body, such that the lead  14  may be effectively advanced through the patient&#39;s vasculature and directed to a desired implant location or site. For example, in some embodiments, the outer member  304  imparts a J-shape upon the lead  14 . The J-shape of the outer member  304  of the medical stylet  300  allows the lead  14  to be placed in the right atrium  26  of the heart  16 . Upon reaching the desired implant location near or in the patient&#39;s heart, the user (e.g., a physician) imparts a torque upon the inner member  302 . This torque is then transferred by the distal tip feature  310  from the inner member  302  to coupling feature  418  on the lead. This torque causes rotation of the helical component, which then advances into and engages the tissue in or near the heart. 
         [0049]      FIG. 5  is a perspective view of a compound-shaped medical stylet  600  for imparting a shape to the lead  14  and for delivering torque to a distal anchoring mechanism of the lead  14 . In an embodiment, the compound shaped medical stylet  600  can be configured to have more than one curve to provide a compound shape to the lead  14 . As shown in  FIG. 5 , the compound shaped medical stylet  600 , according to various embodiments, includes an inner member  608 , an outer member  610 , and an actuating mechanism  612 . The inner member  608  can be similar to the inner member  302  in structure and function. The outer member  610  can be similar to the outer member  304  in structure and function. The actuating mechanism  612  can be similar to the actuating mechanism  326  in structure and function. The inner member  608  can include a distal end portion  618  and a proximal end portion  620 . The outer member  610  can include a distal end portion  614  and a proximal end portion  616 . 
         [0050]    In various embodiments, the compound shaped medical stylet  600  can be configured so that the outer member  610 , the proximal end portion  620 , and the actuating mechanism  612  lie in a first plane  602 . The distal end portion  618  of the first elongate member  608  can be configured to lie in a second plane  606  that is different from the first plane  602 . In some embodiments, the compound-shaped medical stylet  600  is configured so that the outer member  610  defines a curve shape  604  in the plane  606 . In various embodiments, the outer member  610  of the stylet  600  is configured to have a pre-defined shape, wherein the pre-defined shape can be a multi-planar shape. In other embodiments, the medical stylet  600  is configured and shaped to be defined along more than two planes so as to provide a multi-planar shape to the compound-shaped medical stylet  600 . 
         [0051]      FIG. 6  is a flowchart illustrating a method  700  of placing the lead  14  in the heart  16  using a medical stylet  300  or  600 . The method  700  can include inserting the medical stylet that can be similar to the medical stylet  300  or the medical stylet  600  into the lumen  22  defined by the lead  14  in order to provide the desired shape to the lead  14  as illustrated at step  702 . The medical stylet  300  or the medical stylet  600  can be configured to include a first elongate member and a second elongate member for at least partially enclosing the first elongate member; the second elongate member can be configured for providing a shape to the lead  14  in accordance with an anatomical passageway. 
         [0052]    The medical stylet can be similar to the medical stylet  300  or the compound shaped medical stylet  600 . The second elongate member such as the second elongate member  304  of the stylet such as for example, the medical stylet  300  can be a pre-shaped member that can be configured to allow a shape to be provided to the lead  14 , in accordance with the anatomical passageway. The method  700  can further include rotating the medical stylet  300  to cause the first elongate member similar to the first elongate member  302  to engage with the lead  14  to provide torque externally at step  704 . In an embodiment, rotating the medical stylet  300  can cause the tip portion  310  of the first elongate member  302  to engage with the lead  14  to externally provide torque to the lead  14 . The tip portion  310  of the first elongate member  302  can be configured in different shapes, in accordance with the coupler  356  used in the lead  14 . The method  700  can further include guiding the medical stylet  300  along the anatomical passageway to cause the placement of the lead  14  at step  706 . The method  700  can include retracting the medical stylet  300  after placing the lead  14  at the anatomical location.