The invention relates to apparatus and methods for valve replacement and is especially useful in aortic valve repair procedures.
Essential to normal heart function are four heart valves, which allow blood to pass through the four chambers of the heart in one direction. The valves have either two or three cusps, flaps, or leaflets, which comprise fibrous tissue that attaches to the walls of the heart. The cusps open when the blood flow is flowing correctly and then close to form a tight seal to prevent backflow.
The four chambers are known as the right and left atria (upper chambers) and right and left ventricles (lower chambers). The four valves that control blood flow are known as the tricuspid, mitral, pulmonary, and aortic valves. In a normally functioning heart, the tricuspid valve allows one-way flow of deoxygenated blood from the right upper chamber (right atrium) to the right lower chamber (right ventricle). When the right ventricle contracts, the pulmonary valve allows one-way blood flow from the right ventricle to the pulmonary artery, which carries the deoxygenated blood to the lungs. The mitral valve, also a one-way valve, allows oxygenated blood, which has returned to the left upper chamber (left atrium), to flow to the left lower chamber (left ventricle). When the left ventricle contracts, the oxygenated blood is pumped through the aortic valve to the aorta.
Certain heart abnormalities result from heart valve defects, such as valvular insufficiency. Valvular insufficiency is a common cardiac abnormality where the valve leaflets do not completely close. This allows regurgitation (i.e., backward leakage of blood at a heart valve). Such regurgitation requires the heart to work harder as it must pump both the regular volume of blood and the blood that has regurgitated. If this insufficiency is not corrected, the added workload can eventually result in heart failure.
Another valve defect or disease, which typically occurs in the aortic valve is stenosis or calcification. This involves calcium buildup in the valve which impedes proper valve leaflet movement.
In the case of aortic valve insufficiency or stenosis, treatment typically involves removal of the leaflets and replacement with valve prosthesis. However, known procedures have involved generally complicated approaches that can result in the patient being on cardiopulmonary bypass for an extended period of time.
Applicants believe that there remains a need for improved valvular repair apparatus and methods that use minimally invasive techniques and/or reduce time in surgery.
Mitral valve insufficiency can also be problematic. Various approaches to correct mitral valve defects have included valve replacement, valve leaflet repair, chordae tendineae shortening or replacement, and or valve annulus repair also known as annuloplasty. One example where annuloplasty procedures have been developed is in the field of mitral valve insufficiency correction.
Mitral valve insufficiency typically results from a change in the size and shape of the mitral valve annulus. Mitral valve annuloplasty involves reestablishing the normal shape and size of the mitral valve annulus so that it can effect full closure of the valve leaflets.
Approaches to improve valve function (e.g., mitral or tricuspid valve function) have included tissue plication devices and reinforcement of the valve annulus with annuloplasty rings. These approaches have been stated to reestablish the original annulus size and shape and/or prevent further annulus dilation.
Both rigid and flexible annuloplasty rings have been developed. Rigid rings, which generally tend to dictate the shape and contour of the mitral valve annulus, have been considered to somewhat compromise the natural flexibility of the annulus. Flexible annuloplasty rings emerged to provide some degree of compliance in the valve annulus so that the valve could maintain normal physiological motion throughout the cardiac cycle of a beating heart. This is in addition to providing annulus reinforcement. However, it is believed that among the drawbacks of these rings is that they may fold or crimp during implantation and thereby undesirably reduce the size of the valve (e.g., the mitral valve) opening. Also, the sutures used to secure the ring may cause scarring and stiffening of the valve annulus and reduce annulus flexibility over time.
C-shaped bands or partial annuloplasty rings also have been developed. These devices can be attached solely to the posterior portion of the valve annulus which eliminates the need to attach material to the anterior portion of the annulus. Full and partial ring devices are disclosed, for example, in U.S. Pat. No. 3,656,185, which issued to Carpentier.
Other attempts to improve upon valve repair procedures include those described in U.S. Pat. No. 5,450,860, which issued to O'Connor, U.S. Pat. No. 6,183,512, which issued to Howanec, Jr. et al., and U.S. Pat. No. 6,250,308, which issued to Cox.
Applicants believe that there remains a need for improved valvular repair apparatus and methods
The present invention involves valve repair apparatus and methods that overcome problems and disadvantages of the prior art. According to one aspect of the invention, minimally invasive valve removal apparatus is provided, which includes cutting elements configured for delivery to the valve through an aortotomy formed in the patient's aorta. Other aspects of the invention include, but are not limited to replacement valve delivery apparatus.
In one embodiment of the invention, heart valve leaflet removal apparatus comprises a pair of cooperating cutting elements, a holder and members for manipulating the cutting elements. The cooperating cutting elements are adapted for cutting and removing leaflets from an aortic valve in a patient's heart and one of the cutting elements is rotatably coupled the other of the pair of cutting elements. The holder is coupled to one of the cutting elements and is adapted to receive the cut leaflets and the cutting elements and holder are configured for delivery to the aortic valve leaflets through an aortotomy formed in the patient's aorta. In one variation, the pair of cooperating cutting elements and holder have a radial dimension and are radially collapsible.
According to another embodiment of the invention, a heart valve repair system comprises heart valve leaflet removal apparatus comprising a pair of cooperating cutting elements adapted for cutting and removing leaflets from an aortic valve in a patient's heart, one of the cutting elements being rotatably coupled to the other of the pair of cutting elements, a holder coupled to one of the cutting elements and adapted to receive the cut leaflets, the cutting elements and holder being configured for delivery to the aortic valve leaflets through an aortotomy formed in the patient's aorta; and heart valve prosthesis delivery apparatus for placing an aortic valve prosthesis in the patient's heart comprising an aortic valve prosthesis support having a proximal portion and a distal portion and a plurality of fasteners ejectably mounted therein, the distal portion being adapted to be releasably coupled to the aortic valve prosthesis, and the valve prosthesis support being configured for delivery to the heart through the aortotomy formed in the patient's aorta.
According to another embodiment of the invention, a replacement valve delivery system comprises heart valve prosthesis delivery apparatus for placing an aortic stentless valve prosthesis in a patient's heart comprising an aortic stentless valve prosthesis support having a proximal portion and a distal portion and a plurality of fasteners ejectably mounted therein, the distal portion being adapted to be releasably coupled the aortic valve prosthesis, and the valve prosthesis support being configured for delivery to the heart through an aortotomy formed in the patient's aorta; and a balloon adapted to be placed in the valve prosthesis and urge at least a portion of the valve prosthesis against the inner wall of the aorta of the patient so that when adhesive is applied to an exterior portion of the valve prosthesis and the valve prosthesis urged against the inner wall of the aorta the exterior portion can adhere to the inner wall of the aorta
According to another embodiment of the invention, a method of repairing an aortic valve comprises removing aortic leaflets form a patient's aortic valve; providing valve prosthesis on delivery apparatus where the valve prosthesis has an annular portion; introducing the valve prosthesis through an aortotomy formed in the patient's aorta with the delivery apparatus; simultaneously ejecting a plurality of self-closing clips from the delivery apparatus through said annular portion and then into the patient's aortic root to secure the valve prosthesis to the aortic root of the patient.
In yet another embodiment of the invention, heart valve prosthesis includes a curved member and a skirt. The curved member can have first and second ends and be adapted to form a partial ring along a portion of one of the valve annulae in the patient's heart. Alternatively, the curved member can form a fall ring that is adapted to extend along the entire valve annulus. The skirt extends along the curved member and depends therefrom. This prosthesis is especially useful in treating mitral valve insufficiency. In this case, the skirt can be configured so that when the prosthesis is secured to the mitral valve along the mitral valve annulus, the skirt covers the posterior leaflet and the opposed edges of the skirt and anterior leaflet coapt. In addition, when the curved member is secured to the posterior portion of the mitral valve annulus, further annulus dilation can be minimized or eliminated.
According to another embodiment of the invention, heart valve delivery apparatus for placing heart valve prosthesis in a patient's heart comprises a delivery device comprising a plurality of tube pairs arranged to support the heart valve prosthesis; and a plurality of self-closing clips, each clip having an open configuration and a closed configuration and first and second piercing ends, each clip being ejectably mounted to one of the tube pairs with a first portion of the clip slidably postioned in one tube of the tube pair and a second portion slidably postioned in the other tube of the tube pair so that the first clip piercing end can be ejected from the one tube of the tube pair and the second piercing end can be ejected from the other tube of the tube pair.
According to another embodiment of the invention, heart valve repair apparatus for placing heart valve prosthesis in a patient's heart comprises heart valve prosthesis comprising a prosthetic valve leaflet and a member supporting the leaflet; delivery apparatus comprising a support for the valve prosthesis and a plurality of clips ejectably mounted to the delivery apparatus support, each clip having two piercing tips extending into the member supporting the leaflet.
According to another embodiment of the invention, a method for delivering heart valve prosthesis comprises providing heart valve prosthesis having a curved member and a skirt extending therefrom and a plurality of self-closing clips, each having two pointed ends, and an open configuration and a closed configuration; securing the curved member to said plurality of self-closing clips with the two pointed ends of each clip penetrated into the curved member; placing the curved member on the mitral valve annulus of a patient's heart; ejecting all of the clips simultaneously to penetrate into the valve annulus and move toward their closed configuration to secure the heart valve prosthesis to the valve annulus. The above is a brief description of some deficiencies in the prior art and advantages of the present invention. Other features, advantages, and embodiments of the invention will be apparent to those skilled in the art from the following description and accompanying drawings, wherein, for purposes of illustration only, specific forms of the invention are set forth in detail.
FIGS. 15A-C are partial sectional views of a clip delivery mechanism for securing the prosthesis of
FIGS. 16A-C are longitudinal partial cross sections of the clip delivery mechanism of FIGS. 15A-C where
FIGS. 17A-C are partial cross sections of the clip delivery mechanism of FIGS. 16A-C rotated 90 degrees where
Before the present invention is described, it is to be understood that this invention is not limited to the particular embodiments or examples described, as such may, of course, vary. Further, when referring to the drawings, like numerals indicate like elements.
Referring to
Referring to FIGS. 2A-C, one embodiment of minimally invasive valve cutting or removal apparatus is shown and generally designated with reference numeral 100. Apparatus 100 includes a first body member 102 and a second body member 104. First body member 102 includes a tubular member 106 and an umbrella 108 having umbrella arms 110 and a cutting element 112, which is in the form of a spiral. Cutting element 112 can be formed from flat metal wire, such as flat stainless steel wire or ribbon or any other materials suitable for cutting. Umbrella arms 110 each have one end secured to or integrally formed with tubular member 106 and one end secured to or integrally formed with cutting element 112.
Second body member 104 includes an elongated member 114, which can include a knob 116 at one end thereof. Second body member 104 also includes an umbrella 118, which is similar to umbrella 108. Umbrella 118 includes umbrella arms 120 and umbrella cutting element 122, which also is in the form of a spiral. Cutting element 122 can be formed from flat metal wire, such as flat stainless steel wire or ribbon or any other material suitable for cutting. Umbrella arms 120 each have one end secured to or integrally formed with elongated member 114 and one end secured to or integrally formed with cutting element 122.
As shown in
Referring to
Before removing apparatus 100, it again is radially compressed. This can be done by sliding sheath S over apparatus 100. If the second umbrella does not close with the first umbrella, i.e., if the sheath does not readily slide over the second umbrella, the surgeon can retract the apparatus so that the second umbrella is in the vicinity of the aortotomy and manipulate spiral cutting element 122 to reduce the diameter of the second umbrella. The manual manipulation of element 122 can facilitate sliding the sheath thereover or facilitate pulling the unsheathed second umbrella through the aortotomy. In this manner, apparatus 100, together with the cut leaflets are removed from the site through the aortotomy.
Referring to FIGS. 3A-D, another minimally invasive valve cutting or removal apparatus is shown accordance with the present invention and generally designated with reference numeral 200. Valve removal apparatus 200 generally includes a housing 202 and plunger 220 slidably mounted therein.
Housing 202 includes a first tubular portion or member 204, which has an annular cutting edge or element 206 at the distal end thereof, and a second portion or member 208 coupled thereto or integrally formed with first portion or member 204. In the illustrative embodiment, first and second portions or members 204 and 206 are rotatably coupled to one another through an annular tongue 210 and groove 212 arrangement as shown in FIGS. 3B-D. However, other coupling arrangements can be used and members 204 and 206 can be fixedly secured to one another or integrally formed as noted above. Second member or portion 208 includes a chamber forming housing 214 that houses and supports spring 216 and includes vertically aligned holes 218 through which plunger 220 is slidably mounted.
Referring to
In use, the distal portion of leaflet removal apparatus 200, which is adapted for passage through an aortotomy, is passed through such an aortotomy and positioned above the aortic valve leaflets a shown in
According to another aspect of the invention, valve prosthesis delivery apparatus is provided to rapidly deliver the valve prosthesis to the surgical site and to secure the prosthesis at the desired location.
Referring to FIGS. 4A-C, an exemplary embodiment of a valve prosthesis delivery mechanism or apparatus, which is generally designated with reference numeral 300, is shown. Valve prosthesis delivery apparatus 300 generally includes a support for supporting the prosthesis and a plurality of fasteners ejectably mounted in the support.
Referring to
Valve prosthesis delivery apparatus 300 also can include apparatus or a mechanism for expanding support tubes 302 radially outward. In the illustrative embodiment, apparatus 300 includes a plunger 312, which includes elongated member 314. Elongated member 314 has a knob 316 at its proximal end and a slide member 318 at its distal end. Slide member 318 has a plurality of grooves formed therein in which support tubes 302 are slidably mounted. Slide member 318 is sized and/or configured so that when plunger 312 is moved proximally with slide member 318, slide member 318 urges support tubes 302 radially outward.
Plug 308 can be slidably mounted in a tubular housing 320, which can be secured to frustoconical member 304 as shown in the drawings. Housing 320 also is configured to slidably receive cylinder 310.
In use, valve prosthesis such as valve prosthesis 500 is secured to valve prosthesis delivery apparatus 300. Valve prosthesis 500 is schematically shown as a conventional stentless tissue valve, which can be harvested from a suitable animal heart such as a porcine heart and prepared according to known methods. Valve prosthesis 500 includes a root portion 502 and a valve leaflet portion 504, which leaflet portion is shown in the drawings in an open position. In a closed configuration, the valve leaflet edges coapt to seal the valve and prevent regurgitation.
When securing valve prosthesis 500 to delivery apparatus 300, sliding member 318 is moved distally to allow the support tubes to return to their radially inward biased position as shown in
Referring to FIGS. 4A-D, use of apparatus 300 is schematically shown.
Self-closing clips 400 can comprise wire made from shape memory alloy or elastic material or wire so that they tend to return to their memory shape after being released from the clip delivery apparatus. As is well known in the art, shape memory material has thermal or stress relieved properties that enable it to return to a memory shape. For example, when stress is applied to shape memory alloy material causing at least a portion of the material to be in its martensitic form, it will retain its new shape until the stress is relieved as described in U.S. Pat. No. 6,514,265 to Ho, et al., entitled “Tissue Connector Apparatus with Cable Release” and U.S. Pat. No. 6,641,593, entitled “Tissue Connector Apparatus and Methods,” the disclosures of which are hereby incorporated herein by reference. Then, it returns to its original, memory shape. Accordingly, at least a portion of the shape memory alloy of each clip 400 is converted from its austenitic phase to its martensitic phase when the wire is in its deformed, open configuration inside the curved distal end portion of a respective tube 302 (see e.g.,
The nitinol may include additional elements which affect the yield strength of the material or the temperature at which particular pseudoelastic or shape transformation characteristics occur. The transformation temperature may be defined as the temperature at which a shape memory alloy finishes transforming from martensite to austenite upon heating (i.e., Af temperature). The shape memory alloy preferably exhibits pseudoelastic (superelastic) behavior when deformed at a temperature slightly above its transformation temperature. As the stress is removed, the material undergoes a martensitic to austenitic conversion and springs back to its original undeformed configuration. In order for the pseudoelastic wire to retain sufficient compression force in its undeformed configuration, the wire should not be stressed past its yield point in it deformed configuration to allow complete recovery of the wire to its undeformed configuration. The shape memory alloy is preferably selected with a transformation temperature suitable for use with a stopped heart condition where cold cardioplegia has been injected for temporary paralysis of the heart tissue (e.g., temperatures as low as 9-10 degrees Celsius).
The clip can be made by wrapping a nitinol wire having a diameter in the range of about 0.003 to 0.015 inch, and preferably 0.010 inch, and wrapping it around a mandrel having a diameter in the range of about 0.020 to 0.150 inch, and preferably 0.080 inch. The heat treatment of the nitinol wire to permanently set its shape as shown in
The following example is set forth with reference to
A patient is placed on cardio-pulmonary bypass and prepared for open chest/open heart surgery, which typically requires a sternotomy. The surgeon removes the aortic leaflets using valve removal apparatus 100 or 200 as described above. Once the valve has been excised and removed with the valve removal apparatus, the surgeon then places a conventional aortic sizer through the aortotomy to determine the size of the aortic valve replacement (e.g., valve prosthesis 500) as is known in the art.
While in the generally collapsed state shown in
Referring to
Although the foregoing method has been described in connection with open chest surgery, the leaflet removal apparatus and prosthesis delivery apparatus described herein can be used with minimally invasive approaches that typically require a thoracotomy between adjacent ribs. Further, although the minimally invasive valve prosthesis replacement procedure has been described with reference to one prosthetic tissue valve, it should be understood that variations of such prosthesis or other valve prosthesis types can be used.
Referring to
Referring to
Referring to 12A, 13A and 14A, exemplary valve prosthesis 1100 includes a skirt or prosthetic leaflet 1102, which is configured to replace or extend over and cover a leaflet in the valve under repair (e.g., the mitral valve posterior leaflet). Skirt or valve leaflet 1102 can, for example, be made from ePTFE or prosthetic tissue. One prosthetic tissue that can be used is pig leaflet tissue. When repairing a mitral valve, the skirt can be configured to cover the posterior leaflet and effectively replace the posterior leaflet without removing it.
Skirt 1102 is secured to a member or mechanism for holding it in the desired location. In the illustrative embodiment, skirt 1102 is secured to curved member 1104, which can be in the form of an open or partial annuloplasty ring. Skirt 1102 can be secured to ring 1104 by gluing, using conventional medical gluing materials, or sewing or it can be wrapped around ring 1104 and glued or fused to itself. Although not shown, it should be understood that the curved member also can be in the form of a fill, continuous or closed annuloplasty ring.
Member 1104 can be made from any suitable material(s) such as from one or more biocompatible polymers including but not limited to silicone. It also can be covered with Dacron® material such as synthetic polyester textile fiber material or fibrous mesh to assist with tissue ingrowth after implantation. Further, curved member 1104 can be rigid or flexible. Rigid or nonpliable rings, whether full or partial, can improve the ability to reshape the mitral valve annulus. Flexible rings, whether fill or partial, can more readily conform to the mitral valve annulus and accommodate valve movement. In the case where curved member 1104 is to be rigid or nonpliable, suitable plastics can be used. Alternatively, it can be reinforced with a stainless steel or titanium insert(s), which can be in the form of threads or wires extending generally parallel to the longitudinal axis of the curved member, e.g., curved member 1104.
Curved member 1104 also can be provided with a plurality of struts 1106 that extend radially therefrom in an inward direction and provide reinforcement or support for skirt 1102. More specifically, the struts can be curved radially inward and downward to conform to the surface or curvature of replacement leaflet 1102 when replacement leaflet 1102 is in its desired closed position during diastole. The struts, which can be made from the same material as member 1104, can be attached to curved member 1104 or integrally formed therewith, but are not attached to skirt 1102 so that the skirt can move away form the struts during diastole and toward or to the struts during systole. Since the replacement valve leaflet does not have chordae tendineae, the struts are provided to prevent the replacement valve leaflet from folding backward during the systolic cycle. The struts, however, do not extend completely to the inner perimeter of skirt 1102 (see e.g.,
The prosthesis can be secured to the valve by suturing or the use of clips or other fasteners. It can simply be placed on the desired location of the valve and the fasteners placed to secure the prosthesis to the valve. Examples of suitable clips are described in, but not limited to, U.S. Pat. No. 5,972,024 to Northrup, et al. and entitled “Suture-Staple Apparatus and Method,” U.S. Pat. No. 6,514,265 to Ho, et al. and entitled “Tissue Connector Apparatus with Cable Release,” and U.S. Pat. No. 6,613,059 to Schaller, et al. and entitled “Tissue Connector Apparatus and Methods,” the disclosures of which are hereby incorporated herein by reference. Alternatively, the prosthesis can be more rapidly secured to the valve using clip delivery apparatus and/or valve prosthesis delivery apparatus constructed according to further aspects of the invention.
FIGS. 15A-C are partial sectional views of one exemplary embodiment of clip delivery apparatus, which is generally designated with reference numeral 200, for ejecting fasteners through the prosthesis and securing the prosthesis a patient's valve. Apparatus or mechanism 1200 includes a cylindrical housing 1202 and an ejector or plunger 1204 slidably mounted therein. Plunger 1204 includes a piston head 1206 and a piston rod 1208 extending therefrom and terminating in an actuator member or anvil 1210. Clip delivery apparatus 1200 further includes fastener guide tubes 1212, which can be hypotubes and which can have longitudinal slots 1214 extending therethrough. Each guide tube can be integrally formed with housing 1202 or they may be separately formed and secured to the housing by gluing or welding. Referring to FIGS. 15A-C, 16A-C, and 17A-C, as the anvil is pressed and the piston nears or contacts the guide tubes, the self-closing clip shown in the drawings is ejected and if unrestrained, returns to its relaxed state as shown in
One fastener that can be used with clip delivery apparatus is a self-closing clip. One such clip is shown in its open, deformed configuration in
The clip can comprise wire made from shape memory alloy or elastic material so that it tends to return to its memory shape after being released from the clip delivery apparatus. As is well known in the art, shape memory material has thermal or stress relieved properties that enable it to return to a memory shape. For example, when stress is applied to shape memory alloy material causing at least a portion of the material to be in its martensitic form, it will retain its new shape until the stress is relieved as described in U.S. Pat. No. 6,514,265 to Ho, et al. and entitled “Tissue Connector Apparatus with Cable Release” and U.S. Pat. No. 6,641,593 to Schaller, et al. and entitled “Tissue Connector Apparatus and Methods,” the disclosures of which are hereby incorporated herein by reference. Then, it returns to its original, memory shape. Accordingly, at least a portion of the shape memory alloy of clip 1300 is converted from its austenitic phase to its martensitic phase when the wire is in its deformed, open configuration (see e.g.,
The nitinol may include additional elements which affect the yield strength of the material or the temperature at which particular pseudoelastic or shape transformation characteristics occur. The transformation temperature may be defined as the temperature at which a shape memory alloy finishes transforming from martensite to austenite upon heating (i.e., Af temperature). The shape memory alloy preferably exhibits pseudoelastic (superelastic) behavior when deformed at a temperature slightly above its transformation temperature. As the stress is removed, the material undergoes a martensitic to austenitic conversion and springs back to its original undeformed configuration. In order for the pseudoelastic wire to retain sufficient compression force in its undeformed configuration, the wire should not be stressed past its yield point in it deformed configuration to allow complete recovery of the wire to its undeformed configuration. The shape memory alloy is preferably selected with a transformation temperature suitable for use with a stopped heart condition where cold cardioplegia has been injected for temporary paralysis of the heart tissue (e.g., temperatures as low as 9-10 degrees Celsius).
The clip can be made by wrapping a nitinol wire having a diameter in the range of about 0.002 to 0.015 inch, and preferably 0.011 inch, and wrapping it around a mandrel having a diameter in the range of about 0.050 to 0.150 inch, and preferably 0.100 inch. The heat treatment of the nitinol wire to permanently set its shape as shown in
According to another aspect of the invention, valve prosthesis delivery apparatus is provided to rapidly deliver the valve prosthesis to the surgical site and to secure the prosthesis at the desired location.
Referring to
Second member 1404 includes a clip delivery support(s) for supporting a plurality of clip delivery devices 1200. In the illustrative embodiment, a clip delivery support is shown in the form of a partial flat ring 1406. Ring 1406 has a plurality of holes formed therein in which piston rods 1208 of clip delivery apparatus 1200 or devices are disposed. First member 1402 includes a head(s) or anvil(s) adapted to push clip ejectors 1204 in a distal direction to eject clips 300. In the illustrative embodiment, a first member head or anvil is shown in the form of a partial flat ring 1408. First member 1402 also includes a plunger knob or grip 1410 to push member 1402 downwardly when the prosthesis delivery apparatus is positioned over the surgical site as will be discussed in more detail below. Grip 1410 can be in the form of a cylinder with a cap at one end (a closed end cylinder) extending from the frustoconical body portion of first member 1402 as shown in
When clips 1300 are positioned in clip delivery apparatus 1200 in an open, deformed configuration as shown, for example, in
Although particular configurations have been shown regarding first and second members 1402 and 1404 and the clip delivery support and anvil members, other configurations can be used without departing from the scope of the invention. For example, the clip delivery support and anvil members can be full rings.
The following example is set forth to illustrate operation of the invention, and is not intended to limit its scope. Referring to
As noted above, a competent mitral valve (MV) allows one-way flow of oxygenated blood that has entered the left atrium from the lungs to enter the left ventricle. The left ventricle then pumps the oxygenated blood to the rest of the body.
Referring to
The leaflets open and close in response to pressure differences on either side thereof. However, when the leaflets do not fully close, regurgitation and valve insufficiency can result. One method to treat the insufficiency using the implant or prosthetic apparatus of FIG. 12A will be described with reference to
A patient is placed on cardio-pulmonary bypass and prepared for open chest/open heart surgery, which typically requires a sternotomy. The surgeon opens the left atrium of the heart and measures the size and shape of the mitral valve annulus. A valve prosthesis 1100 is selected based on the measured size and shape of the annulus so that ring or partial ring 1104 will conform to the size and shape of the annulus. Accordingly, the size and shape of curved member 1104 is selected to match the size and shape of that portion or all of the annulus upon which it is to be seated. The diameter of curved member 1104 can range form about 18 mm to about 45 mm, and more typically will range from abut 24 mm to about 36 mm. In the case where a partial ring such as illustrative member 1104 is used, the curved member is selected so that it is sized and configured for attachment to the posterior portion of the mitral valve annulus of the patient's heart. The curved member 1104 can then minimize or prevent further dilation of the annulus, while the replacement leaflet 1102 corrects the mitral regurgitation. In this manner, valve prosthesis 100 can simplify valve repair procedures.
The selected valve prosthesis is then aligned with the exposed ends of clips 1300 of valve prosthesis delivery apparatus or mechanism 1400 as shown in
The implanted prosthesis shown in
As noted above, the annuloplasty ring or member 1102 can be constructed to strengthen the annulus and prevent any further distension of the annulus when secured thereto. Member 1102 also can be used to shorten the annulus to treat eschemic mitral regurgitation as is done with annuloplasty rings. In this case, valve prosthesis member 1100 would not be delivered with valve prosthesis apparatus 400. Rather, the portion of member 1100 that is to be secured to the annulus would be delivered or secured to the annulus with sutures in a manner known in the art to shorten the annulus.
Variations and modifications of the devices and methods disclosed herein will be readily apparent to persons skilled in the art. As such, it should be understood that the foregoing detailed description and the accompanying illustrations, are made for purposes of clarity and understanding, and are not intended to limit the scope of the invention, which is defined by the claims appended hereto.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/US04/09790 | 3/30/2004 | WO | 7/11/2006 |
Number | Date | Country | |
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60459385 | Mar 2003 | US | |
60459560 | Mar 2003 | US |