Guidewire filter and methods of use

Abstract

A filter system for temporary placement of a filter in an artery or vein is disclosed. The filter system includes a guidewire that is first positioned across a lesion within a vessel. The guidewire may include a distal stop. A slideable filter is then advanced along the guidewire using an advancing mechanism, typically an elongate member slideable over the guidewire and contacting the filter. A capture sheath may be disposed about the filter during advancement. Once the filter is positioned downstream of the lesion, the capture sheath is withdrawn, allowing the filter to expand. Further distal advancement of the filter is prohibited by the stop. After expansion of the filter, the capture sheath and the advancing mechanism are withdrawn from the region of interest, and removed from the patient's vessel. The filter may then be retrieved using a capture sheath or exchanged for a second filter after removing the first filter.

What is claimed is:  
     
         1 . A method for protecting a patient during an endoluminal procedure, comprising the steps of: 
 advancing a guidewire to a region of interest within a vessel;    advancing a filter and delivery sheath along the guidewire, the filter carried by the delivery sheath;    removing the delivery sheath from the filter, thereby releasing the filter;    expanding the filter within the region of interest;    removing the delivery sheath from the region of interest;    advancing a catheter over the guidewire to the region of interest; and    performing an endoluminal procedure at the region of interest, wherein released embolic material is captured by the filter.    
     
     
         2 . The method of  claim 1 , further comprising the steps of: 
 removing the catheter from the region of interest;    advancing a capture sheath over the guidewire;    engaging the filter with the capture sheath; and    removing the filter and capture sheath from the region of interest.    
     
     
         3 . The method of  claim 1 , wherein the filter is placed on a proximal end of the guidewire after the step of advancing the guidewire into the region of interest within the vessel.  
     
     
         4 . The method of  claim 1 , wherein the step of expanding the filter within the region of interest is performed after the step of removing the delivery sheath from the region of interest.  
     
     
         5 . The method of  claim 1 , wherein the filter is expanded downstream of the region of interest.  
     
     
         6 . The method of  claim 1 , wherein the delivery sheath frictionally engages the filter.  
     
     
         7 . The method of  claim 1 , further comprising a second elongate member disposed within the delivery sheath and having, a distal end operatively associated with the filter.  
     
     
         8 . The method of  claim 1 , wherein the guidewire further comprises a distal stop.  
     
     
         9 . The method of  claim 8 , wherein the guidewire further comprises a proximal stop, and w he rein the filter is released by withdrawing the tubular sheath until the filter bears against the proximal stop.  
     
     
         10 . The method of  claim 2 , further comprising the steps of: 
 advancing a second filter over the guidewire; and    expanding the second filter within the region of interest.    
     
     
         11 . The method of  claim 1 , wherein the filter further comprises a locking mechanism that is operable to engage the guidewire and is releasable to allow the filter to slide along the guidewire, and wherein the method further comprises the step of locking the filter.  
     
     
         12 . The method of  claim 1 , wherein the vessel is a carotid artery.  
     
     
         13 . The method of  claim 1 , wherein the vessel is a coronary artery.  
     
     
         14 . The method of  claim 1 , wherein the catheter is an angioplasty catheter.  
     
     
         15 . The method of  claim 1 , wherein the catheter is a stent deployment catheter.  
     
     
         16 . The method of  claim 1 , wherein the catheter is an atherectomy catheter.  
     
     
         17 . A medical device, comprising: 
 a guidewire having a proximal end, a distal end, and a stop mounted on the distal end;    a delivery sheath having a proximal end, a distal end, and a lumen therebetween, the delivery sheath slideably engaging the guidewire; and    a filter releasably carried within the lumen of the delivery sheath, the filter slideably engaging the guidewire and removable from the guidewire by sliding the filter proximal on the guidewire,    wherein, in use, the guidewire is positioned within a vessel of a patient, the filter and delivery sheath are advanced along the guidewire to a region of interest within the vessel, and the delivery sheath is removed from the filter to release the filter.    
     
     
         18 . The medical device of  claim 17 , further comprising an endoluminal therapeutic catheter.  
     
     
         19 . The medical device of  claim 18 , wherein the endoluminal therapeutic catheter is an angioplasty catheter.  
     
     
         20 . A method for protecting a patient during an endolurninal procedure, comprising the steps of: 
 advancing a guidewire to a region of interest within a vessel;    advancing a filter and delivery sheath along the guidewire, the filter carried by the delivery sheath;    removing the delivery sheath from the filter, thereby releasing the filter;    expanding the filter within the region of interest;    removing the delivery sheath from the region of interest;    advancing a catheter over the guidewire to the region of interest;    performing an endoluminal procedure at the region of interest, wherein released embolic material is captured by the filter;    removing the catheter from the region of interest;    advancing a capture sheath over the guidewire;    engaging the filter with the capture sheath; and    removing the filter and capture sheath from the region of interest.