Self-Expandable Medical Instrument for Treating of Defects in a Patient's Heart

Abstract

The invention relates to a self-expandable medical instrument ( 100 ) for treating defects in a patient's heart, in particular for the transvascular implantation of a prosthetic heart valve ( 30 ), wherein the medical instrument ( 100 ) is introducible into the body of a patient in a minimally-invasive procedure using a catheter system ( 40 ) and comprises a stent ( 1 ) made of a flexible mesh ( 2 ) of thin wires or filaments ( 2′ ). In order to realize a positioning of medical instrument ( 100 ) in the patient's heart which is as precise as possible and to securely anchor same there, it is provided for the stent ( 1 ) composed of the flexible mesh ( 2 ) to exhibit in the expanded state of the medical instrument ( 100 ) a distal retention area ( 10 ) with a laterally-inverted beaded portion ( 12 ) which is engageable in at least one pocket ( 51 ) of the patient's defective heart valve ( 50 ), a proximal retention area ( 20 ), and a center area ( 15 ) positioned between the distal and the proximal retention area ( 10, 20 ).

1 . A self-expandable medical instrument ( 100 ) for treating defects in a patient's heart, in particular for the transvascular implantation of a prosthetic heart valve ( 30 ), wherein the medical instrument ( 100 ) can be introduced into the body of a patient in a minimally-invasive procedure using a catheter system ( 40 ) and comprises a stent ( 1 ) made from a flexible mesh ( 2 ) of thin wires or filaments ( 2 ′), wherein the stent ( 1 ) configured from flexible mesh ( 2 ) exhibits a first predefinable shape during the insertion of the medical instrument ( 100 ) in the patient's body and a second predefinable shape in the implanted state of the medical instrument ( 100 ), wherein said medical instrument ( 100 ) is in a collapsed state in the first shape of the stent ( 1 ) composed of the flexible mesh ( 2 ) and in an expanded state in the second shape of the stent ( 1 ) composed of the flexible mesh ( 2 ), and wherein the stent ( 1 ) composed of the flexible mesh ( 2 ) in its second predefinable shape and in the expanded state of the medical instrument ( 100 ) exhibits the following:
 a distal retention area ( 10 ) having a laterally-inverted beaded portion ( 12 ), which in the implanted state of the medical instrument ( 100 ) is engageable in at least one pocket ( 51 ) of the patient's defective heart valve ( 50 );   a proximal retention area ( 20 ); and   a center area ( 15 ) positioned between the distal and the proximal retention area ( 10 ,  20 ),   
     wherein the center area ( 15 ) of the stent ( 1 ) of the expanded medical instrument ( 100 ) exhibits a smaller diameter than the proximal and/or distal retention area ( 10 ,  20 ), and wherein the center area ( 15 ) is configured to form a positive connection with the vascular wall ( 52 ) at the height of the defective heart valve ( 50 ) in the implanted state of the medical instrument ( 100 ). 
   
   
       2 . The self-expandable medical instrument ( 100 ) according to  claim 1 , wherein the stent ( 1 ) further exhibits a self-expandable prosthetic heart valve ( 30 ) disposed in the center area ( 15 ) which self-expands upon the medical instrument ( 100 ) being released from the catheter system ( 40 ). 
   
   
       3 . The medical instrument ( 100 ) according to  claim 1  or  2 , wherein the mesh ( 2 ) is a mesh tube, and wherein the medical instrument ( 100 ) exhibits a form open to the proximal and distal end in its expanded state. 
   
   
       4 . The medical instrument ( 100 ) according to any one of the preceding claims, wherein the beaded portion ( 12 ) at the distal retention area ( 10 ) of stent ( 1 ) in the expanded medical instrument ( 100 ) is formed by the mushroom-shaped outwardly turning back of the distal end of mesh ( 2 ). 
   
   
       5 . The medical instrument ( 100 ) according to  claim 4 , wherein the beaded portion ( 12 ) at the distal retention area ( 10 ) of stent ( 1 ) in the expanded medical instrument ( 100 ) in the implanted state is invertible into at least one pocket ( 51 ) of the patient's defective heart valve ( 50 ) and thus serves as a means for positioning the medical instrument ( 100 ) at the height of the patient's defective heart valve ( 50 ). 
   
   
       6 . The medical instrument ( 100 ) according to any one of the preceding claims, wherein based upon the self-expanding properties of the mesh ( 2 ), the proximal retention area ( 20 ) of the stent ( 1 ) in the expanded medical instrument ( 100 ) is configured so as to form a force-fit connection with the vascular wall ( 52 ) in the direct proximity of the defective heart valve ( 50 ) in the implanted state of the medical instrument ( 100 ). 
   
   
       7 . The medical instrument ( 100 ) according to any one of the preceding claims, wherein based upon the self-expanding properties of the mesh ( 2 ), the center area ( 15 ) of the stent ( 1 ) in the expanded medical instrument ( 100 ) is configured so as to press the patient's defective heart valve ( 50 ) against the vascular wall ( 52 ) distal the defective heart valve ( 50 ) in the implanted state of the medical instrument ( 100 ). 
   
   
       8 . The medical instrument ( 100 ) according to any one of the preceding claims, wherein the stent ( 1 ) in the expanded state of the medical instrument ( 100 ) exhibits a shape similar to a barbell. 
   
   
       9 . The medical instrument ( 100 ) according to any one of the preceding claims, wherein the center area ( 15 ) of the stent ( 1 ) exhibits a smaller diameter in the expanded medical instrument ( 100 ) than the proximal and distal retention areas ( 10 ,  20 ), and wherein the center area ( 15 ) exhibits a length which corresponds approximately to the length of the defective heart valve ( 50 ). 
   
   
       10 . The medical instrument ( 100 ) according to any one of the preceding claims, wherein the stent ( 1 ) made of mesh ( 2 ) with a self-expandable prosthetic heart valve ( 30 ) arranged at its center area ( 15 ) tapers to the diameter of the catheter system ( 40 ) used in the transvascular surgical procedure. 
   
   
       11 . The medical instrument ( 100 ) according to any one of the preceding claims, wherein the stent ( 1 ) exhibits a mounting ( 4 ) engageable with an explantation catheter system ( 40 ) on its proximal and/or distal end, and wherein the medical instrument ( 100 ) is configured such that an external manipulation will effect its commuting from its expanded state into its collapsed state. 
   
   
       12 . The medical instrument ( 100 ) according to any one of the preceding claims, wherein in the implanted state of the expanded medical instrument ( 100 ), the flexible mesh ( 2 ), in particular wire mesh, of stent ( 1 ) is disposed in multi-layered arrangement around the defective heart valve ( 50 ). 
   
   
       13 . The medical instrument ( 100 ) according to any one of the preceding claims, wherein the stent ( 1 ) made of flexible mesh ( 2 ), in particular wire mesh, having a self-expandable prosthetic heart valve ( 30 ) arranged at its center area ( 15 ) is configured such that the second shape of stent ( 1 ) is adaptable in such a manner to the anatomical conditions so as to achieve on the one hand a maximum expansion of prosthetic heart valve ( 30 ) and, on the other, an optimum lateral sealing to the vascular wall ( 52 ) in the implanted state of the expanded medical instrument ( 100 ). 
   
   
       14 . The medical instrument ( 100 ) according to any one of the preceding claims, wherein the stent ( 1 ) made from flexible mesh ( 2 ), in particular wire mesh, having a self-expandable prosthetic heart valve ( 30 ) arranged at its center area ( 15 ) is configured such that the stent ( 1 ) with the prosthetic heart valve ( 30 ) can be withdrawn back into the catheter system ( 40 ) and removable from the body of the patient at any time during the implantation of the medical instrument ( 100 ). 
   
   
       15 . The medical instrument ( 100 ) according to any one of the preceding claims, wherein the stent ( 1 ) made from flexible mesh ( 2 ), in particular wire mesh, having a self-expandable prosthetic heart valve ( 30 ) arranged at its center area ( 15 ) is configured such that using a catheter system ( 40 ) and guide wires ( 41 ), the stent ( 1 ) with the prosthetic heart valve ( 30 ) is again retractable and explantable following a successful release. 
   
   
       16 . The medical instrument ( 100 ) according to any one of the preceding claims, wherein the flexible mesh ( 2 ) is made from a material having memory effect, in particular nitinol or memory plastics. 
   
   
       17 . The medical instrument ( 100 ) according to any one of the preceding claims, wherein the stent ( 1 ) made from flexible mesh ( 2 ), in particular wire mesh, having a self-expandable prosthetic heart valve ( 30 ) arranged at its center area ( 15 ) is configured so as to replace a patient's aorta valve, mitral valve, pulmonary valve or tricuspid valve.