Tissue slitting methods and systems

Abstract

Methods and systems for separating an object, such as a lead, from formed tissue are provided. Specifically, a tissue slitting device is configured to engage patient formed tissue at a slitting engagement point. While the object is subjected to a first traction force, the tissue slitting device is caused to move further into the engaged tissue and slit the tissue past the point of engagement. The slitting device causes the tissue to separate along an axial direction of the length of the formed tissue and releases at least some of the force containing the object. The methods and systems are well suited for use in cardiac pacing or defibrillator lead explant procedures.

1 - 47 . (canceled) 
     
     
         48 . A tissue-slitting apparatus, comprising:
 a flexible shaft including:
 a proximal portion; 
 a distal portion; and 
 a shaft wall extending between the proximal portion and the distal portion, wherein the shaft wall defines an inner lumen configured to receive a portion of a lead at least partially implanted within tissue growth on a vessel wall of a patient; and 
 a transition region disposed at the distal portion of the shaft and including a tapered section, 
 wherein the tapered section projects radially outward from the shaft wall and includes a cutting surface terminating in a distal tip, 
 wherein the cutting surface is configured to separate the tissue growth from the lead when the portion of the lead is received within the inner lumen to thereby permit the lead to be removed from the patient. 
   
     
     
         49 . The tissue-slitting apparatus of  claim 48 , wherein the shaft further comprises a radiopaque marker proximate to the cutting surface. 
     
     
         50 . The tissue-slitting apparatus of  claim 49 , wherein the radiopaque marker comprises tantalum, tungsten, carbide, iridium, bismuth oxide, barium sulfate, cobalt, platinum, or combinations thereof. 
     
     
         51 . The tissue-slitting apparatus of  claim 48 , wherein a cross-section of the shaft proximal of the transition region is circular, and wherein a cross-section of the shaft distal of the transition region is non-circular. 
     
     
         52 . The tissue-slitting apparatus of  claim 51 , wherein the transition region is tapered relative to the circular cross-section. 
     
     
         53 . The tissue-slitting apparatus of  claim 48 , wherein the cutting surface is spring-loaded toward the inner lumen. 
     
     
         54 . The tissue-slitting apparatus of  claim 48 , wherein the tapered section comprises a wedge and the cutting surface comprises a blade. 
     
     
         55 . The tissue-slitting apparatus of  claim 54 , wherein the tapered section is configured such that the lead is pushed against the blade when the tissue slitting apparatus traverses along an axial length of the lead. 
     
     
         56 . The tissue-slitting apparatus of  claim 55 , wherein the wedge is configured to peel the tissue away from the lead when the tissue slitting apparatus traverses along the axial length of the lead. 
     
     
         57 . The tissue-slitting apparatus of  claim 54 , wherein the blade is formed by an angle of the wedge. 
     
     
         58 . The tissue-slitting apparatus of  claim 48 , wherein the cutting surface is disposed partially within the inner lumen of the shaft. 
     
     
         59 . The tissue-slitting apparatus of  claim 48 , further comprising a lead-locking device, traction device, or snare tool configured to pass through the inner lumen of the shaft. 
     
     
         60 . A tissue-slitting method, comprising:
 providing a flexible shaft including:
 a proximal portion, 
 a distal portion, and 
 a shaft wall extending between the proximal portion and the distal portion, wherein the shaft wall defines an inner lumen; and 
 a transition region disposed at the distal portion of the shaft and including a tapered section, 
 wherein the tapered section projects radially outward from the shaft wall and includes a cutting surface terminating in a distal tip; and 
   receiving within the inner lumen a portion of a lead at least partially implanted within tissue growth on a vessel wall of a patient;   advancing the flexible shaft along the length of the lead such that the tissue growth is separated from the lead by the cutting surface; and   removing the lead from the patient.   
     
     
         61 . The tissue-slitting method of  claim 60 , further comprising tracking a location of the cutting surface based on a radiopaque marker proximate to the cutting surface. 
     
     
         62 . The tissue-slitting method of  claim 60 , further comprising separating the tissue growth from the lead with the cutting surface, wherein the cutting surface is spring-loaded toward the inner lumen such that the cutting surface is pressed against the tissue growth when the portion of the lead is received within the inner lumen. 
     
     
         63 . The tissue-slitting method of  claim 60 , further comprising separating the tissue growth from the lead with the tapered section, wherein the tapered section is a wedge. 
     
     
         64 . The tissue-slitting method of  claim 60 , further comprising separating the tissue growth from the lead with the cutting surface, wherein the cutting surface is a blade formed by an angle of the tapered section. 
     
     
         65 . The tissue-slitting method of  claim 64 , further comprising pushing the lead against the blade when the tissue slitting apparatus traverses along an axial length of the lead. 
     
     
         66 . The tissue-slitting method of  claim 60 , further comprising, with the tapered section, peeling the tissue away from the lead when the tissue slitting apparatus traverses along an axial length of the lead. 
     
     
         67 . The tissue-slitting method of  claim 60 , further comprising separating the tissue growth from the lead with a portion of the cutting surface disposed partially within the inner lumen of the shaft.