US20120303048A1 - Transapical valve replacement - Google Patents

Abstract

Techniques for reaching the interior of the heart, such as for aortic valve replacement, can combine elements of percutaneous implantation methods and elements of surgical implantation methods. In some instances, aortic valve replacement may include a dual transapical approach in which a transfemoral approach is used to reach the apex of the patient's heart from inside the left ventricle while a minimally invasive surgical procedure provides access to the exterior of the apex via an intercostal approach.

Description

CROSS-REFERENCE TO RELATED APPLICATION
• This application claims the benefit under 35 U.S.C, §119(e) of U.S. Provisional Application No. 61/489,435, filed May 24, 2011, which is incorporated herein by reference in its entirety.
TECHNICAL FIELD
• The disclosure relates generally to any procedure performed within the heart (or its main arteries), including closure of ventricular septal defects, repair of aortic aneurysm, ablation of atrial/ventricular arrhythmia, and valve replacement procedures. More particularly, it relates to transapical valve replacement procedures.
BACKGROUND
• Natural heart valves, such as aortic valves, mitral valves, pulmonary valves, and tricuspid valves, often become damaged by disease in such a manner that they fail to maintain bodily fluid flow in a single direction. A malfunctioning heart valve may be stenotic (i.e., calcification of the valve leaflets) or regurgitant (i.e., heart leaflets are wide open). Maintenance of blood flow in a single direction through the heart valve is important for proper flow, pressure, and perfusion of blood through the body. Hence, a heart valve that does not function properly may noticeably impair the function of the heart. Left untreated, valve disease can lead to death. There has been increasing consideration given to the possibility of using, as an alternative to traditional cardiac-valve prostheses, valves designed to be implanted using minimally-invasive surgical techniques or endovascular delivery (so-called “percutaneous valves”).
SUMMARY
• Example 1 is a transapical method of gaining access to an interior of a patient's heart. A first guidewire may be advanced through the ascending aorta and through the aortic valve to a location within the left ventricle. A guide catheter may be advanced over the first guidewire to the location within the left ventricle. A cutting catheter may be advanced over the first guidewire and a balloon catheter having an inflatable balloon may be advanced over the first guide catheter. The inflatable balloon may be inflated proximate the wall of the left ventricle, and the left ventricle wall may be penetrated using the cutting catheter. The interior of a patient's chest may be accessed through an intercostal space that is disposed above the apex of the patient's heart. An S-shaped catheter may be advanced through the intercostal space such that the S-shaped catheter has a distal end positioned proximate the patient's pericardial sac. The pericardial sac may be penetrated using an instrument advanced through the S-shaped catheter. A distal end of the balloon catheter may be connected to the distal end of the S-shaped catheter and the S-shaped catheter may be withdrawn to lift the apex of the heart.
• In Example 2, the method of Example 1 in which the first guidewire is advanced through the patient's vasculature from a femoral access point.
• In Example 3, the method of Example 1 or Example 2 in which accessing the interior of a patient's chest includes penetrating the chest wall through an intercostal space using a hollow needle.
• In Example 4, the method of any of Examples 1-3 in which the instrument used to penetrate the pericardial sac is a hollow needle.
• In Example 5, the method of any of Examples 1-4, further including advancing a port over the balloon catheter.
• In Example 6, the method of Example 5, further including delivering a prosthetic valve through the port.
• Example 7 is a transapical method of gaining access to an interior of a patient's heart. A first hollow needle may be advanced into a patient's chest through an intercostal space, the intercostal space being above the apex of the patient's heart. An S-shaped catheter may be advanced through the first hollow needle such that the S-shaped catheter has a distal end positioned proximate the patient's pericardial sac. A guidewire may be advanced through the S-shaped catheter. A second hollow needle may be advanced over the guidewire to a position proximate the pericardial sac, and the pericardial sac may be penetrated with the second hollow needle. A catheter bearing a cutting blade may be advanced through the second hollow needle and penetrating the heart wall. A catheter including an inflatable balloon on a distal region of the catheter may be advanced, the inflatable balloon may be inflated, and then the catheter may be partially withdrawn to lift the apex of the heart to a higher position proximate the intercostal space through which the first hollow needle was advanced.
• While multiple embodiments are disclosed, still other embodiments of the present invention will become apparent to those skilled in the art from the following detailed description, which shows and describes 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 FIGURES
• FIG. 1 is a schematic view of a method in accordance with an embodiment of the present invention.
• FIG. 2 is a schematic view of a method in accordance with an embodiment of the present invention.
• FIG. 3 is a schematic view of a method in accordance with an embodiment of the present invention.
• FIG. 4 is a schematic view of a method in accordance with an embodiment of the present invention.
• FIG. 5 is a schematic view of a method in accordance with an embodiment of the present invention.
• FIG. 6 is a schematic view of a method in accordance with an embodiment of the present invention.
• FIG. 7 is a schematic view of a method in accordance with an embodiment of the present invention.
• FIG. 8 is a schematic view of a method in accordance with an embodiment of the present invention.
• FIG. 9 is a schematic view of a method in accordance with an embodiment of the present invention.
• FIG. 10 is a schematic view of a method in accordance with an embodiment of the present invention.
• FIG. 11 is a schematic view of a method in accordance with an embodiment of the present invention.
• FIG. 12 is a schematic view of a method in accordance with an embodiment of the present invention.
• FIG. 13 is a schematic view of a method in accordance with an embodiment of the present invention.
• FIG. 14 is a schematic view of a method in accordance with an embodiment of the present invention.
• FIG. 15 is a schematic view of a method in accordance with an embodiment of the present invention.
• FIG. 16 is a schematic view of a method in accordance with an embodiment of the present invention.
• FIG. 17 is a schematic view of a method in accordance with an embodiment of the present invention.
• FIG. 18 is a schematic view of a method in accordance with an embodiment of the present invention.
• FIG. 19 is a perspective view of an embodiment of an implantable prosthetic aortic valve.
• FIG. 20 is a perspective view of an embodiment of an implantable prosthetic aortic valve.
• FIGS. 21A and 21B are schematic illustrations of an embodiment of a delivery device.
• FIG. 22 is a partial cross-section of the delivery device shown inFIGS. 21A and 21B.
• FIG. 23 is a schematic illustration of an embodiment of a delivery device.
• FIG. 24 is an exploded view of the delivery device ofFIG. 23.
• 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
• The invention pertains to techniques for gaining access to the interior of the heart. Once access has been gained to the interior of the heart, a variety of useful procedures may be performed. For illustrative purposes, embodiments of the invention will be described with respect to cardiac valve replacement. In some embodiments, the invention pertains to aortic valve replacement techniques that combine elements of percutaneous implantation methods and elements of surgical implantation methods. In some embodiments, aortic valve replacement may include a transapical approach.
• In some embodiments, as illustrated inFIGS. 1-11, aortic valve replacement may involve a dual transapical procedure in which a transfemoral approach is used to reach the apex of the patient's heart from inside the left ventricle while a minimally invasive surgical procedure provides access to the exterior of the apex via an intercostal approach. In some embodiments, the Seldinger technique may be used to access the interior of the left ventricle.
• FIGS. 1 through 5 illustrate the transfemoral portion of the dual transapical procedure.FIG. 1 illustrates a portion of theleft heart10. Theleft heart10 includes theleft atrium12, theleft ventricle14 and theaorta16. Theaorta16 may be considered as including an ascendingaorta18 and a descendingaorta20. Anaortic valve22 is disposed between theleft atrium12 and theleft ventricle14. Theleft ventricle14 includes an apex15. As seen inFIG. 1, aguidewire24 has been advanced up through the descendingaorta20, through the ascendingaorta18 and through theaortic valve22 into theleft ventricle14. In some embodiments, theguidewire24 may access the vasculature via the femoral artery (not illustrated). In some embodiments, theguidewire24 may instead access the vasculature via a radial or brachial artery (not illustrated) or through theaorta16. In some embodiments, theguidewire24 may include a trilabe centering balloon such as that shown in FIG. 8 of U.S. Patent Publication US 200810147180, which is incorporated by reference herein in its entirety.
• Once theguidewire24 has been placed, additional elements such as a guide catheter may be advanced over theguidewire24 such that the guide catheter passes through theaorta16, through theaortic valve22 and into theleft ventricle14 to a location proximate the apex15. In some embodiments, theguidewire24 may be withdrawn once theguide catheter26 has been placed. As seen inFIG. 2, aguide catheter26 has been advanced over theguidewire24, and theguidewire24 has been withdrawn.
• In some embodiments, a cutting element may be introduced through theguide catheter26. The cutting element may be an elongate hollow needle. In some embodiments, as illustrated inFIG. 2, the cutting element may be a cuttingcatheter28 that includes ablade30 that is secured to the cuttingcatheter28. By advancing the cuttingcatheter28 through theguide catheter26, the vasculature and the cardiac anatomy are protected from potential inadvertent damage that could otherwise be caused by theblade30.
• Before the cuttingcatheter28 is advanced into significant contact with the myocardium, aballoon catheter32 may be advanced over or through theguide catheter26. In some embodiments, as illustrated, theballoon catheter32 may be advanced over theguide catheter26. In some embodiments, theballoon catheter32 includes aninflatable balloon34 disposed at or near a distal end36 of theballoon catheter32. In some embodiments (not illustrated), theguide catheter26 itself includes an inflatable balloon and thus functions as a balloon catheter. In some embodiments, theballoon catheter32 may be advanced over the cuttingcatheter28, particularly if the cuttingcatheter28 includes a configuration in which theblade30 is withdrawn, retracted, folded or otherwise temporarily rendered inert to permit theballoon catheter32 to advance over the cuttingcatheter28. Theballoon catheter32 will include an inflation lumen (not shown) that permits inflation fluid to be communicated to an interior of theinflatable balloon34 in order to inflate theinflatable balloon34.
• InFIG. 2, theguide catheter26 is illustrated as extending distally beyond theballoon catheter32. The cuttingcatheter28 is illustrated as extending distally beyond theguide catheter26. These relative positions are intended merely to be illustrative by showing each of the components in a single drawing but are not intended to describe or suggest any potential limitation regarding the relative positions of each of these components.
• In some embodiments, as illustrated inFIG. 3, the balloon catheter32 (or other catheter optionally carrying an inflatable balloon, such as the guide catheter26) may be advanced towards the apex15 such that theinflatable balloon34 is proximate the apex15. Theinflatable balloon34 may be inflated to provide an air/fluid seal between theballoon catheter32 and the heart wall such that little to no air may enter the heart and such that little or no blood may exit the heart.FIG. 4 is a cross-sectional view illustrating the position of theballoon catheter32 relative to theheart wall40. Once theinflatable balloon34 has been inflated to provide an air/fluid seal between theballoon catheter32 and theheart wall40, and as seen inFIG. 5, the cuttingcatheter28 may be advanced up to and through theheart wall40 to form anaperture42 that extends through theheart wall40 and into thepericardial sac44.
• In some embodiments, the dual transapical procedure also includes an intercostal portion of the procedure, as outlined inFIGS. 6 through 11.FIG. 6 shows theleft ventricle14 and apex15 relative to thepericardial sac44 and theribcage46. The intercostal portion of the procedure begins, in some embodiments, by penetrating the chest wall through theribcage46 using ahollow needle48. In some embodiments, theribcage46 is penetrated through the 4^thintercostal space or the 5^thintercostal space. In some embodiments, theribcage46 is penetrated at a relative level that is above the normal position of the apex15.
• As seen inFIG. 7, thehollow needle48 has penetrated theribcage46 and aguidewire50 has been advanced through thehollow needle48 and down through the space between thepericardial sac44 and theribcage46 to a position proximate (but exterior to the pericardiac sac44) to the apex15. Once theguidewire50 has been placed, a malleable S-shapedcatheter52 is advanced over theguidewire50. In some embodiments, the S-shapedcatheter52 is formed of a shape memory material such as a shape memory polymer or a shape memory metal. It can be seen that adistal end54 of the S-shapedcatheter52 is at a position that is relatively lower than the point at which thehollow needle48 penetrated theribcage46.
• As seen inFIG. 8, ahollow needle56 may be advanced over theguidewire50 or through the S-shaped catheter52 (if theguidewire50 has already been withdrawn) and penetrates thepericardial sac44. At this point, thedistal end54 of the S-shapedcatheter52 is proximate a distal end of either theguide catheter26, the cuttingcatheter28 and/or theballoon catheter32. In some embodiments (not illustrated), aseparate balloon catheter58 including aninflatable balloon60 is advanced through theguide catheter26 to a position proximate thedistal end54 of the S-shapedcatheter52.
• Turning now toFIG. 9, thedistal end54 of the S-shapedcatheter52 is proximate adistal end62 of theballoon catheter58. In some embodiments, thedistal end54 of the S-shapedcatheter52 is configured to capture thedistal end62 of theballoon catheter58 such that the S-shapedcatheter52 may be withdrawn proximally in order to pull thedistal end62 of theballoon catheter58. In some embodiments, magnets may be used to secure thecatheters52 and58 together. In some embodiments, there may be a frictional fit between the two.
• As seen inFIG. 10, theinflatable balloon60 may be inflated such that pulling on theballoon catheter58 causes the apex15 of theleft ventricle14 to be lifted. In some embodiments, theinflatable balloon60 may be configured differently and may be stronger than, for example, theinflatable balloon34 that was used to provide an air/fluid seal. Theballoon catheter58 may be withdrawn proximally a sufficient distance to lift the apex15 of theleft ventricle14 to a position that is aligned or substantially aligned with the initial puncture through theribcage46. The native position of theleft ventricle14 is shown in phantom, illustrating how theleft ventricle14 has been lifted. It will be appreciated that this method provides easy access from a position exterior the chest wall to theaortic valve22.
• As seen inFIG. 11, aport70 may be advanced over theballoon catheter58 to provide access for delivery and deployment of a replacement aortic valve (not shown in this Figure). In some embodiments, theinflatable balloon60 may be deflated before theport70 is advanced over theballoon catheter58 into theleft ventricle14.
• In some embodiments, as illustrated inFIG. 12, theport70 may include structure that helps to secure theport70 relative to theheart wall40 and to prevent air from passing throughport70 into the heart and/or prevent blood from leaking out of the heart. This is particularly useful when the procedures described herein are undertaken off-pump, i.e., with a beating heart, in some embodiments, theport70 includes aninner flange72 and anouter flange74. Theinner flange72 and theouter flange74 may be resilient annular structures that help to secure theport70 relative to theheart wall40. In some embodiments, theinner flange72 and theouter flange74 may be sufficiently resilient to lay flat against theport70 for delivery of theport70 into theheart wall40. In some embodiments, theport70 includes avalve76 such as a hemostasis valve that permits delivery through thevalve76 while preventing air and blood from leaking in either direction through thevalve76.
• In some embodiments, access to theaortic valve22 may be provided without the transfemoral or percutaneous portion of the procedure. In some embodiments, the steps shown inFIGS. 1-5 and9 may be excluded. Another method of providing access to theaortic valve22 is illustrated inFIGS. 13-18.FIG. 13 shows theleft ventricle14 and apex15 relative to thepericardial sac44 and theribcage46. The intercostal portion of the procedure begins; in some embodiments, by penetrating the chest wall through theribcage46 using ahollow needle148. In some embodiments, theribcage46 is penetrated through the 4^thintercostal space or the 5^thintercostal space. In some embodiments, theribcage46 is penetrated at a relative level that is above the normal position of the apex15.
• As seen inFIG. 14, thehollow needle148 has penetrated theribcage46 and aguidewire150 has been advanced through thehollow needle148 and down through the space between thepericardial sac44 and theribcage46 to a position proximate (but exterior to the pericardiac sac44) to the apex15. Once theguidewire150 has been placed, a malleable S-shapedcatheter152 is advanced over theguidewire150. In some embodiments, the S-shapedcatheter52 is formed of a shape memory material such as a shape memory polymer or a shape memory metal. It can be seen that adistal end154 of the S-shapedcatheter152 is at a position that is relatively lower than the point at which thehollow needle48 penetrated theribcage46.
• As seen inFIG. 15, ahollow needle156 may be advanced over theguidewire150 or through the S-shaped catheter152 (if theguidewire150 has already been withdrawn) and penetrates thepericardial sac44. In some embodiments, aballoon catheter158 having aninflatable balloon160 may be advanced through the S-shapedcatheter152. As thehollow needle156 penetrates through thepericardial sac44 and theheart wall40, theballoon catheter158 may be advanced through the resulting aperture and theinflatable balloon160 may be inflated inside theleft ventricle14 in order to provide an air/fluid seal. In some embodiments, a second inflatable balloon (not illustrated) may be disposed just outside theheart wall40 and may be inflated to further seal against air and/or blood.
• In some embodiments, as illustrated inFIG. 16, theinflatable balloon160 may be inflated such that pulling on theballoon catheter158 causes the apex15 of theleft ventricle14 to be lifted. Theballoon catheter158 may be withdrawn proximally a sufficient distance to lift the apex15 of theleft ventricle14 to a position that is aligned or substantially aligned with the initial puncture through theribcage46. The native position of theleft ventricle14 is shown in phantom, illustrating how theleft ventricle14 has been lifted. It will be appreciated that this method provides easy access from a position exterior the chest wall to theaortic valve22.
• As seen inFIG. 17, aport170 may be advanced over theballoon catheter158 to provide access for delivery and deployment of a replacement aortic valve (not shown in this Figure). In some embodiments, theinflatable balloon160 may be deflated before theport170 is advanced over theballoon catheter158 into theleft ventricle14.
• In some embodiments, as illustrated inFIG. 18, theport170 may include structure that helps to secure theport170 relative to theheart wall40 and to prevent air from passing throughport170 into the heart and/or prevent blood from leaking out of the heart. This is particularly useful when the procedures described herein are undertaken off-pump, i.e., with a beating heart. In some embodiments, theport170 includes aninner flange172 and anouter flange174. Theinner flange172 and theouter flange174 may be resilient annular structures that help to secure theport170 relative to theheart wall40. In some embodiments, theinner flange172 and theouter flange174 may be sufficiently resilient to lay flat against theport170 for delivery of theport170 into theheart wall40. In some embodiments, theport170 includes avalve176 such as a hemostasis valve that permits delivery through thevalve176 while preventing air and blood from leaking in either direction through thevalve176.
• Once the port70 (or170) has been deployed, a variety of different valves, including prosthetic aortic valves, may be implanted through the port70 (170). An illustrative but non-limiting example of a suitable prosthetic valve may be seen inFIG. 19,FIG. 19 illustrates avalve301 that can be implanted in a variety of ways, including a minimally invasive procedure. Thevalve301 includes an armature302 and a set ofleaflets303. The armature302 has a general cage-like structure that includes a number of ribs extending along an axis X4. The ribs include a first series ofribs305 and a second series ofribs306. Theribs305,306 may be made of a radially expandable metal. In some embodiments, theribs305,306 may be formed of a shape memory material such as Nitinol.
• The first series ofribs305 and the second series ofribs306 have different functions. In some embodiments, theribs305 form an external or anchor portion of the armature302 that is configured to enable the location and anchorage of thevalve301 at an implantation site. Theribs306 are configured to provide an internal or support portion of the armature302. In some embodiments, theribs306 support a plurality ofvalve leaflets330 provided within the set ofleaflets303.
• In some embodiments, theribs305 are arranged in sets of ribs (threes or multiples of three) such that they are more readily adaptable, hi a complementary way, to the anatomy of the Valsalva's sinuses, which is the site of choice for implantation of thevalve301. The Valsalva's sinuses are the dilatations, from the overall lobed profile, which are present at the root of the aorta, hence in a physiologically distal position with respect to the aortic valve annulus.
• In some embodiments, the structure and the configuration of theribs306 is, as a whole, akin to that of theribs305. In the case of theribs306, which form the internal part of the armature302 of thevalve301, there is, however, usually the presence of just three elements that support, in a position corresponding to homologous lines of commissure (which take material form as sutures331), on thevalve leaflets330. Essentially, the complex ofribs306 andvalve leaflets330 is designed to form the normal structure of a biological valve prosthesis. This is a valve prosthesis which (in the form that is to be implanted with a surgical operation of a traditional type, hence of an invasive nature) has met with a wide popularity in the art.
• In some embodiments, suitable materials used to form theleaflets330, such as the pericardium or meningeal tissue of animal origin are described for example inEP 0 155 245 B andEP 0 133 420 B, both of which are hereby incorporated by reference herein in their entirety. In some embodiments, thevalve301 may be similar to those described in U.S. Patent Publication No. 2005/0197695, which is hereby incorporated by reference herein in its entirety.
• Another illustrative but non-limiting example of a suitable prosthetic valve may be seen inFIG. 20,FIG. 20 illustrates aprosthetic valve401 that can be implanted using a variety of different techniques. In some embodiments, thevalve401 may be implanted using a minimally invasive procedure such as those discussed herein. As illustrated, thevalve401 includes anarmature402 and avalve sleeve403 that is coupled to thearmature402 and that includes threevalve leaflets403a,403band403c.
• As can be seen, thearmature402 has a general cage-like structure and is generally symmetric about a principal axis X1. As shown, thearmature402 defines a lumen which operates as a flow tube or duct to accommodate the flow of blood there through. As will be readily apparent to those skilled in the art, a major characteristic of the present invention is the absence of structural elements that can extend in the lumen through which blood flows.
• Thevalve sleeve403 may be constructed according to various techniques known in the art. For example, in some embodiments, techniques for the formation of the valve leaflets, assembly of the valve sleeve and installation thereof on an armature that can be used in the context of the present disclosure are described in EP-A-0 133 420, EP-A-0 155 245 and EP-A-0 515 324 (all of which are hereby incorporated by reference). In some embodiments, thevalve401 may be similar to those described in U.S. Patent Publication No. 2006/0178740, which is hereby incorporated by reference herein in its entirety.
• As will be understood by those of ordinary skill in the art, in operation, thevalve leaflets403a,403b,403care able to undergo deformation, divaricating and moving up against thearmature402 so as to enable free flow of the blood through the prosthesis. When the pressure gradient, and hence the direction of flow, of the blood through the prosthesis tends to be reversed, thevalve leaflets403a,403b,403cthen move into the position represented inFIG. 20, in which they substantially prevent the flow of the blood through the prosthesis. In some embodiments, thevalve leaflets403a,403b,403care made in such a way as to assume spontaneously, in the absence of external stresses, the closed configuration represented inFIG. 20.
• The prosthetic valves described herein, such as thevalve301 and thevalve401, may be delivered in a variety of different manners. In some embodiments, a prosthetic valve may be delivered in a minimally invasive manner in which the valve is disposed on a delivery apparatus that is configured to be inserted into the patient through the port70 (170) discussed above. Once the prosthetic valve has been appropriately positioned, the delivery apparatus can be manipulated to deploy the valve.
• An illustrative but non-limiting example of a suitable delivery device can be seen inFIGS. 21A and 21B, which are schematic illustrations of adelivery device501. In the illustrated embodiment, thedelivery device501 includes acarrier portion502 for enclosing and carrying a prosthetic device (not visible in this view) and amanipulation portion503 that couples thecarrier portion502 to acontrol handle504. The control handle504 includes several actuator members such as thesliders505 and506. In some embodiments, an optional third actuator member may be provided for controlling translational movement of thecarrier portion502 relative to thecontrol handle504. As will be appreciated, this feature permits microadjustment of thecarrier portion502 and the valve prosthesis in relation to a desired location while the control handle504 is in a fixed location. A further optional actuator on the control handle504 provides rotational adjustment ofcarrier portion502 in relation to manipulation portion50503 and/or control handle4. This permits the optional placement of the valve prosthesis through at least 360 degrees of rotation.
• Themanipulation portion503 may have more than one configuration.FIG. 21A shows a configuration in which themanipulation portion503 is a substantially rigid bar having a length that permits positioning of thecarrier portion503, and hence the prosthetic valve disposed therein, at an aortic valve site. In some embodiments, the substantially rigid bar may have a length of about 10 centimeters. Thedelivery device501 is sized and dimensioned to permit easy surgical manipulation of the entire instruction as well as the actuators on the instrument without contacting parts of the subject in a way to interfere with the users position of the valve prosthesis.
• FIG. 21B illustrates an embodiment in which themanipulation portion503 is an elongated, flexible catheter-like member that can be used for transvascular catherization. However, this embodiment can be used in the procedures discussed herein. In some embodiments, the catheter-like member is braided or is otherwise configured to facilitate torque transmission from the control handle504 to thecarrier portion502 such that the operator may effect radial positioning of thecarrier portion502 during the implantation procedure.
• As shown inFIG. 22, thecarrier portion502 includes twodeployment elements510 and520, each of which are independently operable to allow the expansion of at least one corresponding, radially expandable portion of the valve prosthesis V. In some embodiments, the valve prosthesis V may be self-expanding or may require expansion by another device (such as, for example, balloon expansion).
• In the illustrated embodiment, the valve prosthesis V is self-expanding, and is arranged within thecarrier portion502 such that an expandable portion IF and an expandable portion OF are each located within one of thedeployment elements510,520. Eachdeployment element510,520 may be formed as a collar, cap or sheath. In yet a further embodiment, theelements510,520 are porous (or have apertures) such that blood flow is facilitated prior, during and after placement of prosthesis V. As will be appreciated, blood flows through theelements510,520 and over or through the prosthesis V during the placement procedure. Eachdeployment element510,520 is able to constrain the portions IF, OF in a radially contracted position, against the elastic strength of its constituent material. The portions IF, OF are able to radially expand, as a result of their characteristics of superelasticity, only when released from thedeployment element510,520. Typically, the release of the portions IF, OF is obtained by causing an axial movement of thedeployment elements510,520 along the main axis X2 of thecarrier portion502. In one embodiment, the operator causes this axial movement by manipulating thesliders505 and506, which are coupled to thedeployment elements510,520. In some embodiments, suitable delivery devices such as thedelivery device501 may be found in U.S. Patent Publication No. 2008/0147182, which is hereby incorporated by reference herein in its entirety.
• Another illustrative but non-limiting example of a delivery device may be seen inFIG. 23.FIG. 23 shows an prostheticvalve delivery device700 that includes ahandle701 for manipulation by a practitioner and aholder unit710 for a valve V to be delivered. In the illustrated embodiment, thehandle701 and theholder unit710 are generally located at proximal and distal ends, respectively, of thedevice700. In this, proximal refers to the portion of thedevice700 manipulated by the practitioner while distal refer to the end of thedevice700 at which the valve V is delivered.
• In one embodiment, the valve V includes two annular end portions V1 and V2 and is arranged within theholder unit710 at the distal delivery end of thedevice700 with the annular portions V1, V2 in a radially contracted configuration. In some embodiments, the valve V is delivered by releasing the annular portion V1 first and then by causing the valve V to gradually expand (e.g. due to its elastic or superelastic nature), starting from the portion V1 and continuing to the portion V2, until expansion is compete.
• As shown in the exploded view ofFIG. 24, a shaft706 (which may be either rigid or flexible) extends from thehandle701 to theholder unit710 for the valve. Theholder unit710 includes an annular groove or similar recessed709 formation adapted to receive the (proximal) annular portion V2 of the valve V in a radially contracted condition. A tubular sheath or sleeve is slidably arranged over theshaft706. Such a sleeve (hereinafter the “inner” sleeve) includes a proximal portion705 proximate thehandle701 as well as adistal portion707. The inner sleeve is of a length such that it can extend axially over theshaft706 to form with its marginal end an intermediatetubular member770 of theholder unit710 which surrounds theformation709 to radially constrain and retain the annular portion V2 of the valve V located therein.
• In some embodiments, the proximal portion705 of the inner sheet or sleeve terminates in an annular member750 adapted to abut against astop member702. When in place on theshaft706, thestop member702 prevents the inner sleeve from being retracted (i.e. slid back) along the axis X6 of theshaft706 from the position shown inFIG. 7, where the intermediate member orconstraint770 of theholder unit710 radially constrains and retains the annular portion V2 of the valve V. When thestop member702 is removed or otherwise disengaged, the inner sleeve can be retracted along the axis X6 so that theintermediate member770 of the holder unit releases the annular portion V2 of the valve V.
• In one embodiment, the stop or blockingmember702 includes a fork-shaped body (e.g. of plastics material) adapted to be arranged astride the root portion of theshaft706 between the annular member750 and thehandle701 to prevent “backward” movement of the inner sleeve towards thehandle701.
• A further tubular sheet or sleeve (hereinafter the “outer” sleeve) is slidably arranged over theinner sleeve705,707. Theouter sleeve704 includes a proximal portion having an outer threadedsurface740 to cooperate with a complementary threadedformation730 provided at the inner surface of a tubularrotary actuation member703 arranged around theproximal portion704 of the outer sleeves. In an embodiment, theactuation member703 encloses the annular member750 of the inner sleeve. Theouter sleeve704 extends over theinner sleeve705,707 and terminates with adistal portion708 including an terminal constraint orouter member780 adapted to extend around the distal portion to form an external tubular member of theholder unit710 adapted to radially constrain and retain the annular portion V1 of the valve V located therein.
• In some embodiments, the threaded surface/formations730,740 form a “micrometric” device actuatable by rotating theactuation member703 to produce and precisely control axial displacement of the outer sleeve along the axis X6 of theshaft706. Such a controlled movement may take place along the axis X6 of theshaft706 starting from an extended position, as shown inFIG. 23, where theouter member780 of theholder unit710 radially constrains and retains the valve V. In these embodiments, which allow such a gradual movement or retraction, theouter member780 gradually releases first the annular portion V1 of the valve V and then the remaining portions of the valve located between the annular portion V1 and the annular portion V2, thus permitting gradual radial expansion of the valve V.
• In one embodiment, the retraction movement produced by the “micrometric”actuation device730,740 actuated via therotary member703 is stopped when the distal marginal end of theouter member780 is aligned with the marginal end of theintermediate member770 which still radially constrains and retains the annular portion V2 of the valve V in theformation709. As further described below, in that condition, the valve V is partly expanded (i.e., more or less “basket-like”) with the annular portion V1 completely (or almost completely) expanded and the annular portion V1 still contracted.
• Starting from that position, if thestop member702 is removed or otherwise disengaged, both the inner sleeve and the (retracted) outer sleeve mounted thereon can be slid back along the axis X6 towards thehandle701. In that way, theintermediate member770 of theholder unit710 releases the annular portion V2 of the valve V thus permitting valve expansion to become complete. Valve expansion is not hindered by themember780 as this is likewise retracted towards thehandle701.
• In an illustrative embodiment, the practitioner introduces thedevice700 into the patient's body. In a particular example of aortic valve replacement, thedevice700 may be placed such that theouter member780 is located immediately distal (with respect to blood flow from the left ventricle) of the aortic annulus so that the annular portions V1 and V2 are located on opposite sides of the Valsalva sinuses.
• One thedevice700 is placed such that theouter member780 is disposed properly at the annulus site, therotary actuation member730 may be actuated by rotating the rotary actuation member in such a way that cooperation of the threadedsections730 and740 will cause theouter sleeve704,708 to start gradually retracting towards thehandle701. As a result of this retraction of the outer sleeve, theouter member780 will gradually disengage the annular portion V1 of the valve V. The annular portion V1 will thus be allowed to radially expand.
• Gradual withdrawal of theouter sleeve704,708 proceeds until theouter member780 has almost completely disengaged the valve V, while the annular formation V2 is still securely retained by theintermediate member770 of theinner sleeve705,707 which maintains the annular formation V2 of the valve on theholder portion709. This deployment mechanism of the annular formation V1 and the valve V may be controlled very precisely by the practitioner via the screw-like mechanism730,740 actuated by therotary member703. Deployment may take place in a gradual and easily controllable manner by enabling the practitioner to verify how deployment takes place.
• In some embodiments, so long as the annular formation V2 of the valve V is still constrained within theformation709 by theintermediate member770, the practitioner still retains firm control of the partial (e.g., “basket-like”) expanded valve V. The practitioner will thus be able to adjust the position of the valve V both axially and radially (e.g., by rotating the valve V around its longitudinal axis). This radial adjustment allows the practitioner to ensure that radially expanding anchoring formations of the valve V are properly aligned with the Valsalva sinuses to firmly and reliably retain in place the valve V once finally delivered.
• With the valve V retained by thedevice700 almost exclusively via theintermediate member770 acting on the annular formation V2, the blockingmember702 can be removed from theshaft706, thus permitting the inner sleeve705,707 (and, if not already effected previously, theouter sleeve704,708) to be retracted in such a way to disengage the annular portion V2 of the valve. This movement allows the annular formation V2 (and the valve V as a whole) to become disengaged from thedevice700 and thus becoming completely deployed at the implantation site. This movement can be effected by sliding the inner sleeve (and the outer sleeve) towards thehandle701.
• In some embodiments, the valves described herein such as the valve301 (FIG. 19) or the valve401 (FIG. 20) may be implanted using the delivery devices501 (FIGS. 21A-B) or700 (FIG. 23) in a minimally invasive manner. In some embodiments, the delivery devices may be manipulated remotely using a medical robotic system. Suitable medical robotic systems are described, for example, in U.S. Pat. Nos. 6,493,608; 6,424,885 and 7,453,227, each of which are incorporated herein by reference in their entirety. Illustrative but non-limiting examples of medical robotic systems include those available from intuitive Surgical, Inc., of Sunnyvale Calif. under the da Vinci tradename.
• Various modifications and additions can be made to the exemplary embodiments discussed without departing from the scope of the present invention. For example, while the embodiments described above refer to particular features, the scope of this invention also includes embodiments having different combinations of features and embodiments that do not include all of the described features. Accordingly, the scope of the present invention is intended to embrace all such alternatives, modifications, and variations as fall within the scope of the claims, together with all equivalents thereof.

Claims (7)

1. A transapical method of gaining access to an interior of a patient's heart, the method comprising steps of:

advancing a first guidewire through the ascending aorta and through the aortic valve to a location within the left ventricle;

advancing a guide catheter over the first guidewire to the location within the left ventricle;

advancing a cutting catheter over the first guidewire;

advancing a balloon catheter including an inflatable balloon over the first guide catheter;

inflating the inflatable balloon proximate the wall of the left ventricle;

penetrating the wall of the left ventricle using the cutting catheter;

accessing the interior of a patient's chest through an intercostal space that is disposed above the apex of the patient's heart;

advancing an S-shaped catheter through the intercostal space such that the S-shaped catheter has a distal end positioned proximate the patient's pericardial sac;

penetrating the pericardial sac using an instrument advanced through the S-shaped catheter;

connecting a distal end of the balloon catheter to the distal end of the S-shaped catheter; and

withdrawing the S-shaped catheter to lift the apex of the heart.

2. The method ofclaim 1, wherein the first guidewire is advanced through the patient's vasculature from a femoral access point.

3. The method ofclaim 1, wherein accessing the interior of a patient's chest comprises penetrating the chest wall through an intercostal space using a hollow needle.

4. The method ofclaim 1, wherein the instrument used to penetrate the pericardial sac is a hollow needle.

5. The method ofclaim 1, further comprising advancing a port over the balloon catheter.

6. The method ofclaim 5, further comprising delivering a prosthetic valve through the port.

7. A transapical method of gaining access to an interior of a patient's heart, the method comprising steps of:

advancing a first hollow needle into a patient's chest through an intercostal space, the intercostal space being above the apex of the patient's heart;

advancing an S-shaped catheter through the first hollow needle such that the S-shaped catheter has a distal end positioned proximate the patient's pericardial sac;

advancing a guidewire through the S-shaped catheter;

advancing a second hollow needle over the guidewire to a position proximate the pericardial sac;

penetrating the pericardial sac with the second hollow needle;

advancing a catheter bearing a cutting blade through the second hollow needle and penetrating the heart wall;

advancing a catheter including an inflatable balloon on a distal region of the catheter;

inflating the inflatable balloon; and

partially withdrawing the catheter to lift the apex of the heart to a higher position proximate the intercostal space through which the first hollow needle was advanced.

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