Method and apparatus for providing heat exchange within a catheter body

Abstract

The present invention relates to catheters for selectively cooling or warming tissue within a patient's vasculature. The present invention utilizes novel heat exchanging devices, which reside inside the catheter body for selectively altering the temperature of fluid that flows through the catheter shaft. In addition, the present invention utilizes novel pumping devices, which reside within a patient's vasculature for withdrawing oxygenated blood into the catheter body where heat exchange occurs across a heat transfer interface for selective cooling or warming of the blood occurs. The present invention can be used in a multiplicity of medical disciplines where it is advantageous to selectively alter the temperature of tissue, including beating heart applications, as well as stopped heart medical interventions.

We claim:  
     
         1 . A catheter comprising: 
 a catheter shaft; and    a heat exchanging apparatus extending at least in part within said catheter shaft, said heat exchanging apparatus having a heat transfer interface adapted to alter the temperature of a fluid communicated through the catheter shaft.    
     
     
         2 . The catheter of  claim 1 , wherein said heat exchanging apparatus is further comprised of: 
 a delivery lumen adapted to communicate a heat exchanging medium at least in part through said catheter shaft; and    a return lumen in communication with said delivery lumen for communicating said heat exchanging medium at least in part through said catheter shaft.    
     
     
         3 . The catheter of  claim 2 , wherein said delivery lumen and said return lumen extend in a substantially coaxial relationship.  
     
     
         4 . The catheter of  claim 1 , further comprising a fluid lumen adapted to communicate said fluid through said catheter shaft such that said fluid is in a heat transfer relationship with said heat transfer interface.  
     
     
         5 . The catheter of  claim 4 , wherein said fluid lumen is defined by the internal lumen of a third tubular member.  
     
     
         6 . The catheter of  claim 4 , wherein said fluid lumen is defined by the internal lumen of said catheter shaft.  
     
     
         7 . The catheter of  claim 6 , wherein said fluid lumen is at least in part annular.  
     
     
         8 . The catheter of  claim 6 , wherein said fluid lumen is at least in part crescent shaped.  
     
     
         9 . The catheter of  claim 2 , wherein said heat exchanging medium is selected from the group consisting of compressed refrigerant, liquid nitrogen, water, nitrous oxide and blood.  
     
     
         10 . The catheter of  claim 4 , wherein said fluid lumen is adapted for communicating blood.  
     
     
         11 . The catheter of  claim 4 , wherein said fluid lumen is in fluid communication with a fluid transport system.  
     
     
         12 . The catheter of  claim 11 , wherein said fluid transport system is an internal pump.  
     
     
         13 . The catheter of  claim 11 , wherein said fluid transport system is an external pump.  
     
     
         14 . The catheter of  claim 12 , wherein said heat exchanging apparatus extends through said internal pump.  
     
     
         15 . The catheter of  claim 12 , wherein said heat exchanging apparatus does not extend through said internal pump.  
     
     
         16 . The catheter of  claim 12 , wherein said heat exchanging apparatus extends at least in part in a parallel relationship with said fluid lumen.  
     
     
         17 . The catheter of  claim 1 , further comprising: 
 a guidewire lumen sized and configured for the introduction of a steerable guidewire.    
     
     
         18 . The catheter of  claim 17 , wherein said guidewire lumen is sized and configured for the insertion of a medical device selected from the group consisting of an angioplasty catheter, a stent placement catheter, an atherectomy catheter, a valvuloplasty catheter, an electrophysiology catheter, a transmyocardial revascularization catheter, a patent ductus arteriosus closure catheter, a septal defect repair catheter, an intravascular ultrasonic imaging catheter, a laser angioplasty catheter, a laser ablation catheter, a coil delivery catheter, an embolic delivery catheter, a filter catheter, a carotid stent catheter, a carotid endarterectomy catheter, a tPA drug delivery catheter and a clot dissolving catheter.  
     
     
         19 . The catheter of  claim 1 , further comprising: 
 an expandable membrane coupled to said catheter shaft.    
     
     
         20 . The catheter of  claim 19 , wherein said expandable membrane further comprises at least one expandable rib.  
     
     
         21 . The catheter of  claim 20 , wherein said expandable membrane is in fluid communication with said heat exchanging medium.  
     
     
         22 . The catheter of  claim 1 , further comprising: 
 an occluding member coupled to said catheter shaft.    
     
     
         23 . The catheter of  claim 6 , further comprising: 
 an occluding member coupled to said catheter shaft.    
     
     
         24 . The catheter of  claim 6 , further comprising: 
 an expandable membrane coupled to said catheter shaft.    
     
     
         25 . The catheter of  claim 24 , further comprising: 
 a perfusion port in fluid communication with said fluid lumen; and    a pump adapted to communicate said fluid to said fluid lumen such that said fluid is perfused from said perfusion port.    
     
     
         26 . The catheter of  claim 25 , wherein said pump is an internal pump.  
     
     
         27 . The catheter of  claim 25 , wherein said pump is an external pump.  
     
     
         28 . A method of selectively altering the temperature of tissue comprising the steps of: 
 introducing a catheter having a catheter shaft and a heat exchanging apparatus extending at least in part within said catheter shaft into the vasculature of a patient, said heat exchanging apparatus having a heat transfer interface adapted to alter the temperature of a fluid communicated through the catheter shaft; and    communicating said fluid through said catheter shaft.    
     
     
         29 . The method of selectively altering the temperature of tissue of  claim 28 , further comprising: 
 reducing the temperature of said heat exchanging apparatus.    
     
     
         30 . The method of selectively altering the temperature of tissue of  claim 28 , further comprising: 
 increasing the temperature of said heat exchanging apparatus.    
     
     
         31 . The method of selectively altering the temperature of tissue of  claim 28 , further comprising the step of: 
 expanding an expandable membrane.    
     
     
         32 . The method of selectively altering the temperature of tissue of  claim 28 , further comprising the step of: 
 expanding an occluding member.    
     
     
         33 . The method of selectively altering the temperature of tissue of  claim 28 , further comprising the step of: 
 inserting a medical device through said catheter shaft.    
     
     
         34 . The method of selectively altering the temperature of tissue of  claim 29 , further comprising the step of: 
 pumping blood over said heat exchanging apparatus.    
     
     
         35 . The method of selectively altering the temperature of tissue of  claim 34 , further comprising the step of: 
 cooling the brain with said blood.    
     
     
         36 . The method of selectively altering the temperature of tissue of  claim 35 , further comprising the step of: 
 perfusing the corporeal circulation with a beating heart.    
     
     
         37 . The method of selectively altering the temperature of tissue of  claim 1 , further comprising the steps of: 
 expanding an expandable membrane in the aorta of a patient;    flowing said fluid over said heat exchanging apparatus to cool said fluid;    perfusing the cerebral circulation with said fluid; and    perfusing the corporeal circulation through a heart.    
     
     
         38 . The method of selectively altering the temperature of tissue of  claim 37 , wherein the step of perfusing the corporeal circulation is carried out by: 
 perfusing the corporeal circulation through a beating heart.    
     
     
         39 . The method of selectively altering the temperature of tissue of  claim 37 , wherein the step of perfusing the cerebral circulation is carried out by: 
 perfusing with an internal pump.    
     
     
         40 . The method of selectively altering the temperature of tissue of  claim 37 , wherein the step of perfusing the cerebral circulation is carried out by: 
 perfusing with an external pump.    
     
     
         41 . A catheter comprising: 
 a catheter shaft;    a heat exchanging apparatus extending at least in part within said catheter shaft; and    an expandable membrane coupled to said catheter shaft.    
     
     
         42 . The catheter of  claim 41 , wherein said heat exchanging apparatus is further comprised of: 
 a delivery lumen adapted to communicate a heat exchanging medium at least in part through said catheter shaft; and    a return lumen in communication with said delivery lumen for communicating said heat exchanging medium at least in part through said catheter shaft.    
     
     
         43 . The catheter of  claim 42 , wherein said delivery lumen and said return lumen extend in a substantially coaxial relationship.  
     
     
         44 . The catheter of  claim 43 , wherein said expandable membrane further comprises at least one expandable rib.  
     
     
         45 . The catheter of  claim 44 , wherein said expandable membrane is in fluid communication with said heat exchanging medium.  
     
     
         46 . The catheter of  claim 41 , further comprising: 
 an occluding member coupled to said catheter shaft.