US20070270882A1 - Pericardium management method for intra-pericardial surgical procedures - Google Patents

Abstract

A method for managing the pericardium during intra-pericardial procedures such as the delivery of cardiac support devices. One embodiment of the method includes making an incision through the pericardium to provide access to the pericardial space, and inserting a plurality of strips of lubricious material into and through the incision. The strips of material are spaced around the edges of the incision to form a tubular barrier against the pericardium. End portions of the strips of material in the pericardial space are expanded away from the body to form a lip that lines the inside of the pericardium around the incision.

Description

FIELD OF THE INVENTION
• The invention is a method for manipulating the pericardium during surgical or other procedures requiring access to the pericardial space.
BACKGROUND OF THE INVENTION
• The pericardium is a multi-layer membranous fibro serous sac that surrounds the heart. An inner layer of the pericardium, known as the serous pericardium, is adjacent to the outer layer of the heart, also known as the epicardium. An outer layer of the pericardium is known as the fibrous pericardium. Between the fibrous pericardium and serous pericardium is a space known as the pericardial space. The term “pericardium” is often used, however, to refer only to the fibrous pericardium. Similarly, the term “pericardial space” is often used to refer generally to the space between the fibrous pericardium and the heart.
• Certain surgical or other procedures on the heart require access to the pericardial space through the pericardium. Known approaches for accessing the pericardium and heart from outside the body include sternotomy and sub-xyphoid approaches. One such surgical procedure that requires access to the pericardial space is the delivery of cardiac support devices. Cardiac support devices are structures, sometimes referred to as jackets, that surround all or portions of a diseased heart. These devices are intended to treat chronic heart failure or other cardiac disease, which may be associated valvular dysfunction, by constraining expansion of the heart. They can be delivered and implanted using conventional cardiothoracic surgical techniques or minimally invasive surgical procedures. Devices of these types and associated delivery tools and methods are shown, for example, in the following U.S. patents, all of which are incorporated herein by reference in their entirety.

• 	Inventor Name	Patent/Publication No.
  	Alferness	5,702,343
  	Alferness et al.	6,123,662
  	Vanden Hoek et al.	6,293,906
  	Alferness et al.	6,482,146
  	Lau et al.	6,702,732
  	Walsh et al.	6,902,522
  	Girard et al.	6,951,534

• Tools and methods for accessing the pericardial space and for introducing other instruments and therapeutic devices such as cardiac support devices into that space are also known. Examples of tools and methods of these types are shown in the following U.S. patents and published applications, all of which are incorporated herein by reference in their entirety.

• 	Inventor Name	Patent/Publication No.
  	Grabek	5,931,810
  	Schmidt	5,972,013
  	Schmidt et al.	6,206,004
  	Lau et al.	2005/0055032
  	Lau et al.	2005/0102010

• Cardiac support devices of the type described above are typically delivered through an incision in the pericardium near the apex of the heart. Visualizing the heart and mounting the devices through the incision can involve moving the incision and manipulating the pericardium. In the course of these procedures the pericardium can sometimes interfere with the delivery of the device.
• There is, therefore, a continuing need for improved devices and methods for managing the pericardium during intra-pericardial procedures. Devices and methods that can enhance cardiac support device delivery procedures would be especially desirable.
SUMMARY OF THE INVENTION
• The present invention is an improved method for managing a patient's pericardium during intra-pericardial procedures. The efficiency of procedures such as the delivery of cardiac support devices can be greatly enhanced by the method.
• One embodiment of the invention includes making an incision though the pericardium to provide access to the pericardial space. One or more flexible members are inserted into and through the incision. Portions of the one or more flexible members are formed into a tubular barrier against exposed edges of the pericardium. Portions of one or both ends of the one or more flexible members are formed away from the tubular barrier and around the exposed edges of the pericardium to line at least portions of the pericardium around the incision. The one or more flexible members include a plurality of strips of flexible and lubricious material in one embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
• FIG. 1A is an isometric view of a pericardium management tool in accordance with one embodiment of the present invention in a retracted state.
• FIG. 1B is an isometric view of the pericardium management tool shown inFIG. 1A in an expanded state.
• FIGS. 2A-2C are illustrations of the pericardium management tool shown inFIG. 1A being inserted into and deployed within a patient's pericardial space.
• FIG. 3 is an isometric view of a device for inserting and deploying the pericardium management tool shown inFIG. 1A.
• FIG. 4 is a top view of the deployment device shown inFIG. 3.
• FIG. 5 is an isometric view, taken from the side, showing the pericardium management tool ofFIG. 1A on the deployment device ofFIG. 3, with the internal end of the tool and device inserted into and deployed with the pericardial space.
• FIG. 6 is an isometric view of the deployed tool and device shown inFIG. 5.
• FIG. 7 is an isometric view of a pericardium management tool in accordance with another embodiment of the invention.
• FIGS. 8A-8C are illustrations of the pericardium management tool shown inFIG. 7 being inserted into and deployed within a patient's pericardial space.
• FIG. 9 is a top view of the deployed pericardium management tool shown inFIG. 7.
• FIGS. 10A and 10B are top views of a pericardium retractor in accordance with another embodiment of the invention in closed and open states, respectively.
• FIGS. 11A and 11B are detailed isometric views of the blades of the retractor shown inFIGS. 10A and 10B in the closed and open states, respectively.
• FIGS. 12A and 12B are illustrations of the retractor shown inFIGS. 10A and 10B being inserted into and opened within a patient's pericardial space.
• FIG. 13 is a top view of a pericardium retractor in accordance with another embodiment of the invention inserted into and opened within a pericardial space.
• FIG. 14 is a side view of the retractor shown inFIG. 13 within the pericardial space.
• FIG. 15 is a side view of a pericardium management tool in accordance with another embodiment of the invention deployed within an incision through a patient's pericardium.
• FIG. 16 is an illustration of a plurality of flexible members that can be assembled to form the tool shown inFIG. 15.
• FIG. 17 is a sectional view of an alternative version of one of the flexible members shown inFIG. 16.
• FIG. 18 is a sectional view of another alternative version of one of the flexible members shown inFIG. 16.
• FIG. 19 is a side view of yet another alternative version of one of the flexible members shown inFIG. 16.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
• FIGS. 1A and 1B are illustrations of apericardium management tool10 in accordance with one embodiment of the invention. As shown, thetool10 is a flexible member having atubular body12 with a first orexternal end14 and a second orinternal end16. Abarrier portion18 of thebody12 between theends14 and16 has a diameter D_BP. A lip20 on theexternal end14 of thebody12 has a diameter D_ELthat is greater than the diameter D_BPof thebarrier portion18. Anextendable lip22 on theinternal end16 of thebody12 is expandable with respect to the body between a first or retracted state shown inFIG. 1A and a second or expanded state shown inFIG. 1B. In the retracted state shown inFIG. 1A, theextendable lip22 has a diameter D_IL1that can be greater than, less than or equal to the diameter D_BPof thebarrier portion18. In the embodiment shown, theextendable lip structure22 has a diameter D_IL1in its retracted state that is slightly larger than the diameter D_BPof thebarrier portion18. In the expanded state shown inFIG. 1B, theextendable lip structure22 has a diameter D_IL2that is greater than the diameter D_BPof thebarrier portion18.
• In the embodiment shown inFIGS. 1A and 1B, theentire body12 is formed from flexible (i.e., compliant) material such as fabric manufactured of expanded PTFE threads. Material of this type is commercially available as Gore-Tex fabric from W.L. Gore. Some embodiments of the invention are formed from material that is also expandable, although other embodiments of the invention are constructed from material that is not expandable. Materials of this type can also be elastic, although other embodiments of the invention are constructed from material that is not elastic. Another characteristic of material of this type is that it has a relatively low coefficient of friction, and therefore has relatively low friction surfaces. Still other embodiments of the invention are formed from other materials (e.g., Dacron) having a lubricious coating.
• In the embodiment ofpericardium management tool10 shown inFIGS. 1A and 1B, thelip20 on theexternal end14 ofbody12 is fixed in size. Thelip20 can, for example, be formed by stretching the fabric around a hoop (not visible) of wire or other elongated material to form atubular pocket23, and forming a hem in the fabric to retain the hoop inside the tubular pocket. As shown inFIGS. 1A and 1B, in this embodiment of thetool10, the diameter of thebody12 continuously increases between the diameter D_BPof thebarrier portion18 and the diameter D_ELof theexternal lip20.
• Theextendable lip22 is moved between its retracted and expanded states in this embodiment by a flexible elongated element such aswire24 that is inserted into and withdrawn from atubular pocket26 in theinternal end16 of thebody12.Pocket26 can be formed by folding and hemming the fabric on theend16 of thebody12. By forcing thewire24 in a direction generally parallel to its length into thepocket26 through a hole (not shown), the wire is be formed into a hoop of increasing circumference and diameter that stretches the fabric of thebody12 to expand thelip22. Thelip22 is retracted by withdrawing thewire24 from thepocket26.
• FIGS. 2A-2C illustrate a method for operating and deploying thetool10 to manage a patient'spericardium30 and provide access toheart32. Thepericardium30 is accessed from a desired location through the patient'sskin31. Anincision34 is then made through thepericardium30 to provide access to thepericardial space36 surroundingheart32. As shown inFIG. 2A, theinternal end16 of thebody12 is inserted through theskin31 andincision34, and positioned within thepericardial space36. Thelip20 on theexternal end14 of thebody12 will remain on the outside of thepericardium30, and typically on the outside of the patient'sskin31.
• The expansion oflip22 can then be initiated by forcing thewire24 into thepocket26 as shown inFIG. 2B. As thewire24 is fed into thepocket26 the circumference and diameter of thelip22 will expand with respect to thebarrier portion18 and draw theinternal end16 of thebody12 closer to the interior surface ofpericardium30. This expansion operation continues until thelip22 is in its expanded state shown inFIG. 2C. When thetool10 is deployed with thelip22 in the expanded state, thebarrier portion18 of thebody12 forms a tubular structure around and against the exposed edges of thepericardium30 andskin31. Thelip22 also extends beyond the edges of theincision34 and forces the fabric of the lip andbody12 to be positioned on or adjacent to the interior surfaces of thepericardium30 around the incision. Thelip22 thereby covers or lines the inside surface of thepericardium30 around theincision34. Similarly, this deployment causes theexternal lip20 to be located on or least adjacent to the external surface of the patient'sskin31, with the fabric of the external lip andbody12 extending beyond and around the opening over the external surface of the skin to form a cover or lining.
• Tool10 can be efficiently inserted and deployed. The deployedtool10 surrounds theincision34 in thepericardium30 and provides a low-friction access port to thepericardial space36. Since the edges of thepericardium30 at theincision34 are covered and protected, they will not interfere with surgical or other procedures being performed through the deployedtool10. The deployedtool10 also engages thepericardium30 around theincision34 to such a degree that the tool can be manipulated to lift, shift or otherwise move the location of thebarrier portion18, and therefore the access port, as desired during the surgical procedure. The surgeon can thereby effectively enhance his or her visualization of and access to thepericardial space36 without interference from the edges of thepericardium30. The characteristics of thetool10 also enable the device to continually resize and conform to changes in the shape or size of theincision34 that might be caused during the surgical procedure.
• Upon completion of the surgical or other procedure thetool10 can be removed from theincision34. This removal can be facilitated by returning thelip22 on theinternal end16 to its retracted state (e.g., by withdrawing the wire24). The above described advantages of thetool10 are thereby achieved by a device that can be efficiently removed following the completion of the procedure.
• Pericardial management tools in accordance with the invention and having features and advantages such as those described above in connection withtool10 can take other forms. By way of example, and not shown, in other embodiments of the invention thebarrier portion18 andlip20 onexternal end14 can be formed of rigid materials such as polymers. Thelip20 on theexternal end14 need not be fixed, but instead can have structures such as those of thelip22 on theinternal end16 that can be moved between retracted and expanded states. Theextendable lip22 can also be formed from different materials, including rigid materials, and different structures and methods can be used to move the lip between its retracted and expanded states. In still other embodiments, the tool includes a low friction material coating (e.g., in solid or liquid form) on the interior surfaces of thebody12 or at least on thebarrier portion18. Theentire tool10, or just portions, can be constructed from any suitable material such as, for example, fabrics, metals, polymers or biologic materials. The exterior surface of thetool10 near thelips20 and/or22 can also include adhesive elements or coatings, or other tissue-engaging structures or material, that will facilitate the attachment of the lips to the adjacent tissue when the device is deployed. Although thetubular body12 has a circular cross section in the illustrated embodiment, other embodiments (not shown) have other cross sectional shapes.
• FIGS. 3 and 4 are illustrations of adeployment device50 that can be used to insert and deploy thepericardium management tool10. As shown,deployment device50 has ahandle52 with a pair ofguide members54 extending from one end. Theguide members54 are tubes and havefingers56 on the ends opposite thehandle52 that extend in a direction back toward and generally parallel to the handle. Thewire24 that is used to deploy the tool10 (not shown inFIGS. 3 or4) extends through theguide members54 and out the ends of thefingers56. The portion of thewire24 extending from thefingers56 forms a hoop that is located in theextendable lip22 of thetool10 when the tool is mounted on thedeployment device50, thereby supporting the tool during its use. The ends of thewire24 extending from the ends of theguide members54 mounted to thehandle52 are connected to aslide60.Slide60 is movably mounted to thehandle52, and in the embodiment shown is mounted to aslot62 for movement along the length of the handle. The circumference and diameter of the hoop in thewire24 can be expanded and retracted by moving theslide60 toward and away from the end of thehandle52 with theguide members54, respectively.
• FIGS. 5 and 6 are illustrations of thepericardium management tool10 mounted to thedeployment device50. Acover64 of flexible fabric encloses the portions of thedeployment device50 between theslide60 and end portion ofhandle52. Theinternal end16 andextendable lip22 of the tool10 (not visible inFIGS. 5 and 6) are positioned through anincision34 intomammalian pericardium30 in these figures. Theslide60 has been actuated (e.g., by the surgeon's thumb) to drive theextendable lip22 to its expanded state. InFIG. 6 thepericardial space36 andheart32 are visible through the opening in thebody12.
• FIG. 7 is an illustration of apericardium management tool110 in accordance with another embodiment of the invention. As shown,tool110 includes ahoop170 and abody112 formed by a plurality of flexible members such as material strips172. The material strips172 can be formed of any of the materials of thebody12 oftool10 described above. In one embodiment, for example, strips172 are formed of relatively low friction and flexible material such as PTFE. Thestrips172 extend from the hoop at spaced apart locations and can be formed of relatively thin sheet material.Hoop170 can be an elongated metal or polymer member (e.g., wire). Material strips172 can be attached to thehoop170 by wrapping the ends of the strips around the hoop and securing the ends to the hoop or adjacent portions of the strips (e.g., by a sewn hem or adhesive). Theend114 oftool110 at which the material strips172 are attached to thehoop170 is an exterior end of the tool, while the free ends of the strips are at aninternal end116 of the tool.
• FIGS. 8A-8C and9 illustrate a method for operating and deploying thetool110 to manage a patient'spericardium130 and provide access toheart132. Thepericardium130 is accessed from a desired location through the patient'sskin131. Anincision134 is then made through thepericardium130 to provide access to thepericardial space136 surroundingheart132. As shown inFIG. 8A, the portions ofmaterial strips172 on theinternal end116 of thebody112 are inserted through theskin131 andincision134, and positioned within thepericardial space136. Thebody112 of thedevice10 is in a retracted state during this insertion step. Thehoop170 on theexternal end114 of thebody112 functions as alip120 and remains on the outside of thepericardium130, and typically on the outside of the patient'sskin131.
• Thebody112 oftool110 is then expanded within thepericardial space136 by radially extending the free ends of the material strips172 in a fanned arrangement under thepericardium130. The portions of the material strips172 on theinternal end116 of thebody112 are thereby expanded in diameter and circumference with respect to the diameter and circumference of abarrier portion118 that engages the edges of thepericardium130 at theincision134. These steps can be done by hand (e.g., by the surgeon using his or her fingers to tuck the material strips172 under the pericardium130) or with the assistance of instruments. The portions of the material strips172 on theends116 of thebody112 form alip122 under thepericardium130. This expansion operation continues until thelip122 is in its expanded state shown inFIG. 8C.
• As perhaps best shown inFIGS. 8C and 9, when thetool110 is deployed with thelip122 in the expanded state, the portions of the material strips172 atbarrier portion118 are positioned closely adjacent to one another and form a tubular structure against the exposed edges of thepericardium130 andskin131. In the illustrated embodiment the portions of the material strips172 atbarrier portion118 are located immediately adjacent to one another. In other embodiments (not shown) thestrips172 can overlap one another, or be spaced from one other, atbarrier portion118.
• Thelip122 extends beyond and around the edges of theincision134 and forces the material strips172 to be positioned on or adjacent to the interior surfaces of thepericardium130 around the incision, thereby lining the pericardium around the incision. When deployed, the illustrated embodiment oftool110 has gaps in thelip122 between the material strips172. However substantial portions of thepericardium130 around theincision134 are still lined by the lip122 (e.g., sufficient portions to reduce or prevent the pericardium from interfering with the surgical procedure). Following this deployment operation theexternal lip120 will typically be located on or at least adjacent to the external surface of the patient'sskin131, with the material ofstrips172 at thelip120 andbody112 extending beyond and around the opening over the external surface of the skin.
• Pericardium management tool110 can be efficiently inserted and deployed to surround the incision and provide a low-friction access port to thepericardial space136.FIG. 9, for example, shows how the deployedtool110 provides access to thepericardial space136 andheart132. Thetool110 can be removed from theincision134 following the completion of the surgical procedure by returning thelip122 to its retracted state and pulling thebody112 out of the incision. The functions and associated advantages provided bypericardium management tool110 are the same or similar to those oftool10 described above.
• Pericardium management tools in accordance with the invention having features and advantages such as those described above in connection withtool110 can take other forms. By way of example, and not shown, in other embodiments if the invention the portions of the strips172 (e.g., flexible members) that are positioned on the outside and/or the inside of thepericardium130 can be formed of rigid material, and the portions of the strips forming thebarrier portion118 can be formed of flexible material or have hinge structures that enable the ends to be fanned out within thepericardial space136. Malleable metals or other material or structures can be added to the material strips172 at thebarrier portion118 to cause the strips to retain their expanded state positions. The strips need not be formed of low friction material, but can instead be formed of other materials and have a coating of low friction material on at least those portions forming the interior surface ofbarrier portion118. The material strips172 can also be curved or otherwise shaped to reduce or eliminate the size of the gaps between the strips at thelips120 and/or122 when thetool110 is deployed. Adhesive or other structures (e.g., hook and loop fasteners) on the material strips (e.g., on the edges) can be used to secure the strips to one another. Other features of thetool10 described above can also be incorporated intotool110.
• Aretractor200 in accordance with another embodiment of the invention is shown inFIGS. 10A and 10B.Retractor200 includes ahandle202, a pair ofblades204 and anactuating member208.Blades204 are shown in greater detail inFIGS. 11A and 11B. Theretractor200 andblades204 are shown in a closed or retracted position inFIGS. 10A and 11A with the blades located adjacent to one another, and in an open or extended position inFIGS. 10B and 11B with the blades spaced apart from one another.
• Blades204 each have anupright wall portion210 and alip212 extending from the wall portion.Wall portions210 have a convex surface in the embodiment shown. Similarly, in the embodiment shown thelips212 have a convex outer edge. In other embodiments of the invention thewall portions210 and the outer edges of thelips212 have other shapes (e.g., are flat or straight).
• Handle202 is an elongated member in the embodiment shown and has aproximal end214 and adistal end216. One of the blades204 (i.e., a fixed blade) is mounted to thedistal end216 of thehandle202 with thelip212 facing theproximal end214. An elongated member such asshaft215 can mount the fixedblade204 to thehandle202. Actuatingmember208 includes aU-shaped arm217 with aproximal end218 movably mounted to thehandle202 and adistal end220 mounted to the other blade204 (i.e., the movable blade). Theblade204 is mounted to thedistal end220 ofarm217 with thelip212 of the blade facing away from thedistal end216 of thehandle202. In the embodiment shown, theproximal end218 ofarm217 is slidably mounted to a slot222 in thehandle202 by an aslide224.
• The operation ofretractor200 can be described with reference toFIGS. 10A,10B,11A,11B,12A and12B. Thepericardium230 is accessed from a desired location through the patient'sskin231. Anincision234 is then made through thepericardium230 to provide access to thepericardial space236. With thehandle202 and actuatingmember208 manipulated so theblades204 are in the closed position shown inFIGS. 10A and 11A, the blades are inserted through theincision234 to position thelips212 within thepericardial space236 as shown inFIG. 12A. The actuatingmember208 is then actuated to move theblades204 to the open position shown inFIGS. 10B and 11B. This expansion of theblades204 will cause thewall portions210 of the blades to engage the exposed edges of thepericardium230, and thelips212 to extend beyond the edges of the incision over the inside surface of thepericardium230. Theincision234 is thereby spread apart, and the edges of thepericardium230 at the incision engaged, to provide access to thepericardial space236 andheart232. A releasable clamp mechanism (not shown) on the handle can be used to retain theretractor200 in the open position during surgical procedures. Upon completion of the surgical procedure theretractor200 can be returned to its closed position and withdrawn from theincision234.
• Retractor200 can be efficiently operated. Theretractor200 provides functions and advantages that are the same or similar to those described above in connection withtool10.Retractor200 can be used alone to access thepericardial space236. Alternatively, tools such as10 and110 described above can be used in connection with theretractor200 by inserting them into the opening created by the retractor.
• FIGS. 13 and 14 are illustrations of aretractor300 in accordance with another embodiment of the invention. In these figures theretractor300 is shown in an open state with theblades304 within thepericardium330 of a mammal, exposing the pericardial space336 and heart332. In the embodiment shown, the actuating mechanism and handle ofretractor300 formed by a hand-heldclamp mechanism303 having a pair ofarms305 pivotally connected by ahinge307. Areleasable locking mechanism311 is connected to the hand-engagingsections313 of thearms305. Theblades304 are mounted directly to thearms305. The edges of thelips312 are generally linear, and thewall portions310 are generally planar. Other than these differences,retractor300 can be substantially the same or similar toretractor200 described above, and functions in manner that is substantially the same or similar to that ofretractor200.
• FIG. 15 is an illustration of apericardium management tool410 in accordance with another embodiment of the invention.Tool410 is formed from a plurality of individual material strips472 such as those shown inFIG. 16. Material strips472 can be formed from any of the materials and/or structures ofmaterial strips172 oftool110 described above (e.g., low friction and flexible materials), and have anexternal end414 and aninternal end416. In the embodiment shown, the material strips472 are elongated members having concave side edges475.Adhesive473 is located on at least one side of the material strips472 adjacent to at least one of the edges.
• Tool410 is deployed by inserting the material strips472 individually into anincision434 in thepericardium430. Internal ends416 are then tucked under the internal surface of thepericardium430, and the external ends414 are bent over the outside of thepericardium430 or body. Adjacent side edges475 of the material strips472 can be joined together. In the embodiment shown inFIGS. 15 and 16, for example, the side edges475 are overlapped and secured together by the adhesive473. When deployed, thetool410 has atubular body412 with abarrier portion418 that engages and surrounds the edge of thepericardium430 at theincision434. The internal ends416 of the material strips472 are extended from retracted positions to form anextendable lip422 that lines the interior surface of thepericardium430 around theincision434. The external ends414 form alip420 on the outside surface of thepericardium430 or body.
• Pericardium management tool410 can be efficiently inserted and deployed to surround theincision434 and provide a low-friction access port to thepericardial space436. Thetool410 can be removed from theincision434 following the completion of the intra-pericardial procedure by pulling thebody412 out of the incision. The functions and advantages provided bypericardial management tool410 are the same or similar to those oftools10 and110 described above.
• Pericardium management tools in accordance with the invention having features and advantages such as those described above in connection withtool410 can take other forms. By way of example,FIG. 17 illustrates a cross section of amaterial strip472′ having an arcuate cross section. The actuate cross section ofmaterial strip472′ provides the strip with beam strength, and enhances the its ability to be deployed as part of the tool.FIG. 18 illustrates theexternal end414″ of amaterial strip472″. As shown, theend414 includes an engagement structure such aspocket481″ that can be engaged by an instrument or other tool during the deployment of the tool.FIG. 19 illustrates amaterial strip472′″ having a tissue-engaging structure such as adhesive strip485′″ on itsexternal end414′″ and amalleable material strip483′″ adjacent thebarrier portion418′″. Adhesive strip485′″ can be used to enhance the engagement of theend414′″ with the pericardium (not shown) when deployed as part of the tool in the manner described above.Malleable material strip483′″ can help thematerial strip472′″ retain its shape when deployed as part of the tool, yet allow the material strip to be returned to other shapes during the removal of the tool. Of course the features of the material strips shown inFIGS. 17-19 can be combined with one another and with the features of the material strips472 described above. Similarly, features of thetools10 and110 described above can be incorporated intomaterial strips472 andtool410. Other structures such as snaps, magnets or hook and loop fasteners can be used as alternatives to the adhesive473 to secure the material strips472 to one another. The material strips472 can have side edges with straight or other shape profiles, and need not be configured to engage adjacent material strips along their entire lengths. A plurality of the material strips472 can be distributed together as a kit for assembling the tool. For example, in one embodiment (not shown) a plurality of the material strips472 are packaged together as a kit for this purpose.
• Although the present invention has been described with reference to preferred embodiments, those skilled in the art will recognize that changes can be made in form and detail without departing from the spirit and scope of the invention. For example, although not shown, tools and methods in accordance with the invention can be incorporated into delivery tools for cardiac support devices.

Claims (20)

1. A method for managing a patient's pericardium during an intra-pericardial procedure, including:

making an incision though the pericardium to provide access to the pericardial space;

inserting one or more flexible members into and through the incision;

forming portions of the one or more flexible members into a tubular barrier against exposed edges of the pericardium; and

extending portions of one or both ends of the one or more flexible members away from the tubular barrier and around the exposed edges of the pericardium to line at least portions of the pericardium around incision.

2. The method ofclaim 1 wherein inserting one or more flexible members includes inserting a tubular structure formed of flexible material.

3. The method ofclaim 2 wherein extending end portions of the one or more flexible members includes forming a lip on an end of the tubular structure.

4. The method ofclaim 3 wherein forming the lip includes actuating an actuating member to form the lip.

5. The method ofclaim 4 wherein actuating an actuating member includes forming a hoop on the end portion of the tubular structure.

6. The method ofclaim 3 wherein inserting one or more flexible members into the incision includes inserting flexible sheet material into the incision.

7. The method ofclaim 2 wherein extending end portions of the one or more flexible members includes forming a lip on an end of the tubular structure within the pericardial space and under the pericardium.

8. The method ofclaim 1 wherein inserting one or more flexible members includes inserting a plurality of flexible members.

9. The method ofclaim 8 wherein inserting a plurality of flexible members includes inserting a plurality of strips of flexible material.

10. The method ofclaim 9 wherein forming the tubular barrier includes circumferentially spacing the strips of material around the edges of the incision.

11. The method ofclaim 9 wherein extending end portions of the flexible members includes fanning the end portions of the flexible material away from the tubular barrier.

12. The method ofclaim 9 wherein inserting flexible material includes inserting ends of strips of material extending from circumferentially spaced locations around a hoop into the incision.

13. The method ofclaim 9 wherein inserting the strips of flexible material includes inserting the strips within the pericardial space and extending ends of the strips under the pericardium.

14. The method ofclaim 9 wherein inserting flexible material includes inserting material having a relatively low friction surface.

15. The method ofclaim 9 wherein forming a portion of the one or more flexible members into a tubular barrier includes attaching at least portions of the strips of flexible material to one another.

16. The method ofclaim 1 wherein inserting one or more flexible members includes inserting relatively low friction members.

17. The method ofclaim 1 wherein extending portions of one or both ends of the one or more flexible members includes increasing a diameter of the portions of the members extending away from the tubular barrier with respect to a diameter of the tubular barrier.

18. The method ofclaim 1 wherein:

inserting one or more flexible members includes inserting a plurality of flexible members; and

forming portions of the flexible members into a tubular barrier includes positioning edges of the flexible members adjacent to one another.

19. The method ofclaim 18 wherein positioning edges of the flexible members adjacent to one another includes overlapping the edges of the flexible members.

20. The method ofclaim 18 and further including attaching portions of the edges of adjacent flexible members.

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