Systems and methods for removal of blood and thrombotic material

Abstract

A method for improving a flow condition through a catheter advancing an aspiration catheter through a sheath such that an open distal end of the aspiration lumen of the aspiration catheter is distal to a distal end of a sheath and is in proximity to a thrombus within a blood vessel of a subject, coupling an extension conduit in fluid communication with a lumen of the sheath to a fluid source, and activating a pump such that pressurized fluid from a first fluid source is supplied to a supply lumen of the aspiration catheter and when insufficient flowable material is present adjacent the open distal end of the aspiration lumen, fluid from the second fluid source is caused to flow through the lumen of the sheath.

What is claimed is: 
     
         1 . A method for identifying a no flow or low flow condition through a catheter, comprising:
 coupling a first fluid source to a supply lumen of the aspiration catheter, the aspiration catheter comprising:
 a supply lumen and an aspiration lumen, the aspiration lumen having an open distal end; and 
 an opening at or near the distal end of the supply lumen, the opening configured to allow the injection of pressurized fluid from a first fluid source into the aspiration lumen at or near the distal end of the aspiration lumen when the pressurized fluid is caused or allowed to flow through the supply lumen; 
   coupling a vacuum source to the aspiration lumen of the aspiration catheter;   positioning a sheath within the vasculature of a subject, the sheath comprising:
 a proximal end; 
 a distal end; 
 a lumen extending between the proximal end and the distal end, the lumen being configured for placement of the aspiration catheter therethrough; and 
 an extension conduit in fluid communication with the lumen of the sheath and extending from the sheath; 
   with the sheath within the vasculature of the subject, placing the aspiration catheter through the sheath and advancing the aspiration catheter such that the open distal end of the aspiration lumen of the aspiration catheter is in proximity to a thrombus within a blood vessel of the subject;   coupling the extension conduit to an auxiliary fluid supply system; and   activating the pressurization element such that pressurized fluid from the first fluid source is applied to the proximal end of the supply lumen of the aspiration catheter, wherein when sufficient flowable material is present adjacent the open distal end of the aspiration lumen, at least some of the flowable material is caused to flow through the aspiration lumen from the open distal end to the proximal end, and into an interior of the vacuum source, and when insufficient flowable material is present adjacent the open distal end of the aspiration lumen, fluid from the auxiliary fluid supply system is caused to flow through the lumen of the sheath between the proximal end and the distal end.   
     
     
         2 . The method of  claim 1 , further selecting the fluid from the auxiliary fluid supply system to flow through the lumen of the sheath. 
     
     
         3 . The method of  claim 2 , further comprising selecting contrast agent to flow through the lumen of the sheath. 
     
     
         4 . The method of  claim 3 , further comprising visualizing on fluoroscopy a portion of a lumen of the blood vessel at or adjacent the distal end of the sheath as a result of the contrast agent flowing through the lumen of the sheath from the proximal end to the distal end and into the blood vessel. 
     
     
         5 . The method of  claim 2 , wherein selecting the fluid from the auxiliary fluid supply system comprises selected between a contrast agent source and a saline fluid source. 
     
     
         6 . The method of  claim 5 , wherein the contrast agent source comprises a syringe having a barrel and plunger longitudinally movable within the barrel, the barrel configured to contain the contrast agent. 
     
     
         7 . The method of  claim 2 , further comprising increasing compression of the saline fluid source to a pressure of at least 250 mm Hg. 
     
     
         8 . The method of  claim 2 , wherein selecting the fluid from the auxiliary fluid supply system comprises rotating a valve in fluid communication with a plurality of fluid sources. 
     
     
         9 . The method of  claim 1 , further comprising detecting a signal from a pressure sensor in communication with a conduit in fluid communication with the aspiration lumen. 
     
     
         10 . The method of  claim 9 , wherein the conduit is a vacuum line in communication with the vacuum source. 
     
     
         11 . The method of  claim 10 , wherein the pressure sensor comprises an input port with a septum. 
     
     
         12 . The method of  claim 10 , further comprising adding fluid within the vacuum line. 
     
     
         13 . The method of  claim 10 , further comprising removing fluid from within the vacuum line. 
     
     
         14 . The method of  claim 10 , further comprising removing air from the vacuum line. 
     
     
         15 . The method of  claim 10 , further comprising priming at least the aspiration lumen of the aspiration catheter. 
     
     
         16 . The method of  claim 1 , further comprising:
 changing a relative longitudinal relationship between the aspiration catheter and the sheath such that the distal end of the aspiration catheter is within the lumen of the sheath and proximal to the distal end of the sheath; and   viewing a plunger of a syringe associated with the auxiliary fluid supply system while a pump is activated, wherein movement of the plunger into the barrel indicates a previous insufficiency of flowable material adjacent the open distal end of the aspiration lumen.   
     
     
         17 . The method of  claim 16 , wherein longitudinal movement of the plunger into the barrel indicates active flow through the aspiration catheter. 
     
     
         18 . The method of  claim 1 , further comprising:
 changing a relative longitudinal relationship between the aspiration catheter and the sheath such that the distal end of the aspiration catheter is within the lumen of the sheath and proximal to the distal end of the sheath; and   viewing a plunger of a syringe associated with the auxiliary fluid supply system while a pump is activated, wherein no longitudinal movement of the plunger in relation to the barrel indicates blockage in the aspiration catheter.