摘要:
Valve prostheses are disclosed that are adapted for secure and aligned placement relative to a heart annulus. The valve prostheses may be placed in a non-invasive manner, e.g., via transcatheter techniques. The valve prosthesis may include a resilient ring, a plurality of leaflet membranes mounted with respect to the resilient ring, and a plurality of positioning elements movably mounted with respect to the flexible ring. Each of the positioning elements defines respective proximal, intermediate, and distal tissue engaging regions cooperatively configured and dimensioned to simultaneously engage separate corresponding areas of the tissue of an anatomical structure, including respective first, second, and third elongate tissue-piercing elements. The proximal, distal, and intermediate tissue-engaging regions are cooperatively configured and dimensioned to simultaneously engage separate corresponding areas of the tissue of an anatomical structure so as to stabilize a position of the valve prosthesis with respect to the anatomical structure, including wherein for purposes of so simultaneously engaging the separate corresponding areas of tissue, at least one of the first, second, and third elongate tissue-piercing elements is pointed at least partially opposite the direction of blood flow, and at least another thereof is pointed at least partially along the direction of blood flow. The valve prosthesis may also include a skirt mounted with respect to the resilient ring for sealing a periphery of the valve prosthesis against a reverse flow of blood around the valve prosthesis.
摘要:
Valve prostheses are disclosed that are adapted for secure and aligned placement relative to a heart annulus. The valve prostheses may be placed in a non-invasive manner, e.g., via trans-catheter techniques, and may be positioned/repositioned until proper alignment and positioning is achieved. The valve prosthesis may include a resilient ring, a plurality of leaflet membranes mounted with respect to the resilient ring, and a plurality of positioning elements movably mounted with respect to the flexible ring, each of the positioning elements defining a first tissue engaging region and a second tissue engaging region spaced from the first tissue engaging region. The positioning elements are adapted to substantially completely invert by rotating relative to the resilient ring between a first position in which each of the first and second tissue engaging regions is inwardly directed for facilitating positioning of the valve prosthesis within a delivery catheter, and a second position in which each of the first and second tissue engaging regions is outwardly directed for engaging tissue. The valve prosthesis may also include a valve skirt mounted with respect to the resilient ring.
摘要:
Valve prostheses are disclosed that are adapted for secure and aligned placement relative to a heart annulus. The valve prostheses may be placed in a non-invasive manner, e.g., via trans-catheter techniques, and may be positioned/repositioned until proper alignment and positioning is achieved. The valve prosthesis may include a resilient ring, a plurality of leaflet membranes mounted with respect to the resilient ring, and a plurality of positioning elements movably mounted with respect to the flexible ring, each of the positioning elements defining a first tissue engaging region and a second tissue engaging region spaced from the first tissue engaging region. The positioning elements are adapted to substantially completely invert by rotating relative to the resilient ring between a first position in which each of the first and second tissue engaging regions is inwardly directed for facilitating positioning of the valve prosthesis within a delivery catheter, and a second position in which each of the first and second tissue engaging regions is outwardly directed for engaging tissue. The valve prosthesis may also include a valve skirt mounted with respect to the resilient ring.
摘要:
Polyionic derivatives of cyclodextrins and methods for preparing these derivatives are provided in which a polyionic derivative of cyclodextrin is combined with a growth factor, preferably a heparin binding growth factor. These compositions are of low solubility and are applied directly to the location of a wound. By virtue of the low solubility, the compositions remain in place at the site of application and slowly release growth factor. In an alternative embodiment, the cyclodextrin derivatives are administered in the absence of growth factor and are used to absorb growth factor present in the body at the location of the wound in order to prevent overstimulation of the wound response.
摘要:
Disclosed are compositions and methods effective for inhibiting restenosis. In particular, the present invention provides compositions for inhibiting undesired smooth muscle cell growth or proliferation following angioplasty in mammals, said composition comprising active agents comprising a very water-soluble derivative of cyclodextrin. The invention also provides methods of inhibiting undesired smooth muscle cell growth or proliferation following angioplasty in mammals comprising orally administering to the mammal a growth-inhibiting amount of an active agent comprising a very water-soluble derivative of cyclodextrin.
摘要:
A percutaneously inserted bistable heart valve prosthesis is folded inside a catheter for transseptal delivery to the patient's heart for implantation. The heart valve has an annular ring, a body member having a plurality of legs, each leg connecting at one end to the annular ring, claws that are adjustable from a first position to a second position by application of external force so as to allow ingress of surrounding heart tissue into the claws in the second position, and leaflet membranes connected to the annular ring, the body member and/or the legs, the leaflet membranes having a first position for blocking blood flow therethrough and a second position for allowing blood flow therethrough. The heart valve is designed such that upon removal of the external force the claws elastically revert to the first position so as to grip the heart tissue positioned within the claws, thereby holding the heart valve in place. The body member and claws may be integrated into a one-piece design. The heart valve may be used as a prosthesis for the mitral valve, aortic valve, pulmonary valve, or tricuspid valve by adapting the annular ring to fit in a respective mitral, aortic, pulmonary, or tricuspid valve opening of the heart.
摘要:
Valve prostheses are disclosed that are adapted for secure and aligned placement relative to a heart annulus. The valve prostheses may be placed in a non-invasive manner, e.g., via trans-catheter techniques. The valve prosthesis may include a resilient ring, a plurality of leaflet membranes mounted with respect to the resilient ring, and a plurality of positioning elements movably mounted with respect to the flexible ring. Each of the positioning elements defines respective proximal, intermediate, and distal tissue engaging regions cooperatively configured and dimensioned to simultaneously engage separate corresponding areas of the tissue of an anatomical structure, including respective first, second, and third elongate tissue-piercing elements. The proximal, distal, and intermediate tissue-engaging regions are cooperatively configured and dimensioned to simultaneously engage separate corresponding areas of the tissue of an anatomical structure so as to stabilize a position of the valve prosthesis with respect to the anatomical structure, including wherein for purposes of so simultaneously engaging the separate corresponding areas of tissue, at least one of the first, second, and third elongate tissue-piercing elements is pointed at least partially opposite the direction of blood flow, and at least another thereof is pointed at least partially along the direction of blood flow. The valve prosthesis may also include a skirt mounted with respect to the resilient ring for sealing a periphery of the valve prosthesis against a reverse flow of blood around the valve prosthesis.
摘要:
Polyionic derivatives of cyclodextrins and methods for preparing these derivatives are provided in which a polyionic derivative of cyclodextrin is combined with a growth factor, preferably a heparin binding growth factor. These compositions are of low solubility and are applied directly to the location of a wound. By virtue of the low solubility, the compositions remain in place at the site of application and slowly release growth factor. In an alternative embodiment, the cyclodextrin derivatives are administered in the absence of growth factor and are used to absorb growth factor present in the body at the location of the wound in order to prevent overstimulation of the wound response.
摘要:
A method and device that addresses the problem of an incompetent aortic valve by using a simple cardioplegia catheter that can deliver cardioplegia solution to the coronary arteries through the usual aortic cannulation site even in the presence of aortic valve incompetence. The device includes a cardioplegia cannula (32) with an additional lumen containing a nitinol wire (34) inside it that allows advancement of a folded nitinol umbrella (36) with a non-porous membrane or a compressed nitinol ring that covers the aortic valve when opened. During installation, after puncture of the aorta by the coaxial needle and removal of the coaxial needle but before installation of the cardioplegia solution through the central lumen of the catheter, the nitinol umbrella (in folded position) or nitinol ring (in compressed position) is advanced through the second lumen into the aorta just above the aortic valve. The nitinol umbrella is unfolded using the nitinol wire to expose the inverted umbrella configuration with attached membrane and is then advanced as a unit with the cardioplegia catheter until the nitinol umbrella covers the aortic valve at its deployed position.
摘要:
A percutaneously inserted bistable heart valve prosthesis is folded inside a catheter for transseptal delivery to the patient's heart for implantation. The heart valve has an annular ring, a body member having a plurality of legs, each leg connecting at one end to the annular ring, claws that are adjustable from a first position to a second position by application of external force so as to allow ingress of surrounding heart tissue into the claws in the second position, and leaflet membranes connected to the annular ring, the body member and/or the legs, the leaflet membranes having a first position for blocking blood flow therethrough and a second position for allowing blood flow therethrough. The heart valve is designed such that upon removal of the external force the claws elastically revert to the first position so as to grip the heart tissue positioned within the claws, thereby holding the heart valve in place. The body member and claws may be integrated into a one-piece design. The heart valve may be used as a prosthesis for the mitral valve, aortic valve, pulmonary valve, or tricuspid valve by adapting the annular ring to fit in a respective mitral, aortic, pulmonary, or tricuspid valve opening of the heart.