Apparatus and procedure for trapping embolic debris

Abstract

A collapsible and deployable filter for blocking debris and passing blood in a blood vessel in a patient's body, the filter including; a framework of a flexible material, constructed to have a radially compressed state, in which the framework is radially compressed by radial deforming forces, and a radially expanded state to obdurate an artery; and a flexible filter material secured to said framework and having pores dimensioned to prevent the passage of debris therethrough while allowing the passage of blood. The filter has, in the radially expanded state of the framework, a generally conical or frustoconical form with a large diameter end, a small diameter end opposite to the large diameter end, and a side surface extending between the ends. The filter has an opening that is free of filter material at the small diameter end or in the side surface.

What is claimed is: 
     
         1 . A collapsible and deployable filter for blocking debris and passing blood in a blood vessel in a patient's body, said filter comprising;
 a framework of a flexible material, said framework being constructed to have a radially compressed state, in which said framework is radially compressed by radial deforming forces, and a radially expanded state; and   a flexible filter material secured to said framework and having pores dimensioned to prevent the passage of debris therethrough while allowing the passage of blood, wherein:   said filter has, in the radially expanded state of said framework, a generally conical or frustoconical form with a large diameter end, a small diameter end opposite to said large diameter end, and a side surface extending between said large diameter end and said small diameter end;   said flexible filter material covers at least a major part of said side surface;   said large diameter end is open to receive blood and debris and is dimensioned to prevent flow of blood between said large diameter end and the blood vessel wall when said framework is in the radially expanded state; and   said filter has an opening that is free of filter material at said small diameter end or in said side surface.   
     
     
         2 . A device for removing debris from a blood vessel, comprising:
 the filter according to  claim 1 ; and   a sheath having an internal diameter selected to house said filter in the radially compressed state, said sheath having a length sufficient to extend out of a patient's body when said filter is at a desired location in a blood vessel.   
     
     
         3 . The device of  claim 2 , wherein said opening is at said small diameter end of said filter, and said device further comprises:
 a tube having a distal end communicating with said opening for removal of debris collected in said filter, said tube having a proximal end and having a length sufficient to enable said proximal end to extend out of a patient's body when said filter is at a desired location in the blood vessel.   
     
     
         4 . The device of  claim 3 , further comprising:
 a second filter connected to said proximal end of said tube for separating debris conveyed through said tube from blood conveyed through said tube.   
     
     
         5 . The device of  claim 4 , further comprising:
 a source of contrast fluid connectable to said tube.   
     
     
         6 . The device of  claim 5 , further comprising a valve member installed in said tube in proximity to said proximal end of said tube, said valve member having a first operating state for placing said source of contrast fluid in fluid flow communication, through said tube, with the region enclosed by said filter and blocking flow to said second filter, and a second operating state placing the region enclosed by said filter in fluid flow communication, through said tube, with said second filter and blocking flow to and from said source of contrast fluid. 
     
     
         7 . A procedure for removing debris from a blood vessel in a patient's body and allowing blood to pass through the blood vessel, comprising, in the order recited:
 providing the device according to  claim 6 ;   introducing said filter into the blood vessel;   placing said valve member in the first operating state and passing contrast fluid from said source of contrast fluid through said tube; and   placing said valve member in the first operating state and causing debris to flow through said tube from the region enclosed by said filter to said second filter.   
     
     
         8 . The procedure of  claim 7 , further comprising passing blood that has been separated from the debris in said second filter to a second blood vessel. 
     
     
         9 . Apparatus for removing debris from blood flowing through a blood vessel, comprising:
 the device according to  claim 2 ; and   a debris removal device operative to extend into the space enclosed by said filter and to conduct debris from the space enclosed by said filter to a location outside the patient's body   
     
     
         10 . The apparatus of  claim 9 , further comprising an assembly for implanting a prosthetic aortic valve in the patient's heart. 
     
     
         11 . A procedure for implanting a prosthetic aortic valve in the patient's heart while blocking flow of debris through the aorta, comprising:
 providing the apparatus of  claim 10 ,   inserting said filter, in its radially compressed state in said sheath, along a blood vessel path into the aorta;   withdrawing said sheath to cause said filter to assume the radially expanded state at a desired location on the aorta;   inserting said assembly for implanting a prosthetic aortic valve in the patient's heart into the aorta through said opening of said filter, and through said large diameter end of said filter and passed an existing heart valve;   operating said assembly to implant the prosthetic aortic valve;   withdrawing said assembly from the patient's body;   conveying debris resulting from said inserting and operating steps, with debris removal device, from the region enclosed by said filter to a location outside the patient's body; and   withdrawing said assembly from the patient's body.   
     
     
         12 . The procedure of  claim 11 , further comprising supplying contrast medium to the location where the valve is implanted. 
     
     
         13 . The procedure of  claim 12 , wherein the contrast medium is supplied through the debris removal device. 
     
     
         14 . The apparatus of  claim 9 , wherein said opening is at said small diameter end of said filter, and said debris removal device comprises a tube having a distal end communicating with the region enclosed by said filter through said opening and dimensioned to have a proximal that extends out of the patients body when said filter is in the desired location in a blood vessel. 
     
     
         15 . The filter of  claim 1  wherein said opening is at said small diameter end of said filter. 
     
     
         16 . The filter of  claim 15 , further comprising at least one control wire having a distal end connected to said framework at the small diameter end of said filter. 
     
     
         17 . A device for removing debris from a blood vessel, comprising;
 the filter according to  claim 16 ; and   a sheath having an internal diameter selected to house said filter in the radially compressed state, said sheath having a length sufficient to extend out of a patient's body when said filter is at a desired location in a blood vessel.   
     
     
         18 . The filter of  claim 1  wherein said opening is in said side surface of said filter. 
     
     
         19 . A filter for blocking debris and passing blood in a blood vessel in a patient's body, said filter having a generally conical form and comprising: a large diameter end; a small diameter end and a side surface, said filter being open at said large diameter end and being provided with an opening in small diameter end or on said side surface. 
     
     
         20 . A device for trapping debris produced during a surgical procedure performed on a patient, said device comprising:
 a collapsible and deployable filter for blocking debris and passing blood in a blood vessel in a patient's body, a guidewire connected to said filter, and a sheath in which said filter is housed,   said filter comprising;
 a framework of a flexible material, said framework being constructed to have a radially compressed state, in which said framework is radially compressed by radial deforming forces, and a radially expanded state; and 
 a flexible filter material secured to said framework and having pores dimensioned to prevent the passage of debris therethrough while allowing the passage of blood, wherein: 
 said filter has, in the radially expanded state of said framework, a generally conical form with a large diameter end, a closed end opposite to said large diameter end, and a side surface extending between said large diameter end and end; 
 said flexible filter material covers the entirety of said side surface from said large diameter end to said closed end; and 
 said large diameter end is open to receive blood and debris and is dimensioned to prevent flow of blood between said large diameter end and the blood vessel wall when said framework is in the radially expanded state; 
   said sheath having a distal end and having a length and flexibility sufficient to extend through the patient's blood vessels and heart from a point outside the patient's body to the patient's pulmonary artery;   said guidewire extending through said sheath and having a distal end connected to said closed end of said filter with said filter being oriented,   wherein said filter is extendable from said distal end of said sheath and is movable , with the aid of said guidewire, between said radially compressed state within said sheath and said radially expanded state when said filter is extended from said distal end of said sheath, and said filter is oriented such that said large diameter end faces said distal end of said sheath when said filter is extended from said distal end of said sheath.   
     
     
         21 . A method for blocking debris in a pulmonary artery of a patient undergoing a surgical procedure on the heart, using said device as defined in  claim 20 , said method comprising:
 advancing said sheath with said filter in the radially compressed state within said sheath, through a vein and the heart of the patient to bring said distal end of said sheath into the pulmonary artery of the patient;   bringing said filter to a location in the pulmonary artery of the patient outside of said distal end of said sheath to move said filter to the radially expanded state;   performing the surgical procedure; and   after the surgical procedure, withdrawing said device from the patient's body.