Methods and devices for cryogenic carotid body ablation

Abstract

Methods and cryogenic devices for assessing, and treating patients having sympathetically mediated disease, involving augmented peripheral chemoreflex and heightened sympathetic tone by reducing chemosensor input to the nervous system via carotid body ablation. Some methods include advancing a cryo-ablation catheter into a patient's vasculature and ablating tissue within a carotid septum.

What is claimed is: 
     
         1 . A method for cryo-ablating target tissue within a carotid septum of a patient, the method comprising:
 advancing a balloon catheter towards a bifurcation of an internal carotid artery and an external carotid artery of a patient, the balloon catheter comprising a first arm and an expandable balloon,   passing the first arm into the internal carotid artery and engaging the first arm with the carotid artery bifurcation;   passing the balloon into the external carotid artery and expanding the balloon;   advancing a cryo-ablation catheter supporting a cryo-ablation element out of an exit port in the catheter such that the cryo-ablation element is disposed adjacent the carotid septum; and   actuating the cryo-ablation element to ablate at least a portion of the carotid septum.   
     
     
         2 . The method of  claim 1  further comprising retracting a sheath to cause the first arm to assume a preformed configuration in which it extends from an axis of the balloon catheter at between about 30 and about 60 degrees. 
     
     
         3 . The method of  claim 1  wherein advancing a cryo-ablation catheter out of an exit port comprises advancing a cryo-ablation catheter out of a side exit port in the catheter. 
     
     
         4 . The method of  claim 3  further comprising engaging the cryo-ablation element with the wall of the external carotid artery. 
     
     
         5 . The method of  claim 1  wherein advancing a cryo-ablation catheter out of an exit port comprises advancing a cryo-ablation catheter out of an exit port in the catheter and into the interior of the expandable balloon. 
     
     
         6 . The method of  claim 5  further comprising engaging the cryo-ablation element into contact with interior of the balloon wall. 
     
     
         7 . A method for cryo-ablating target tissue within a carotid septum of a patient, the method comprising:
 advancing a cryo-ablation catheter into an artery of a patient, the cryo-ablation device comprising first and second arms;   passing the first arm into an external carotid artery of the patient and into engagement with a wall of the external carotid artery adjacent a carotid septum;   passing the second arm into an internal carotid artery of the patient and into engagement with a wall of the internal carotid artery adjacent the carotid septum; and   delivering a cryogen fluid through the first and second arms to ablate at least a portion of the carotid septum.   
     
     
         8 . The method of  claim 7  wherein advancing a cryo-ablation catheter into an artery of a patient comprises advancing the first and second arms in collapsed delivery configurations. 
     
     
         9 . The method of  claim 7  further comprising retracting a sheath to cause the first and second arms to deploy to preformed delivery configurations. 
     
     
         10 . A method for cryo-ablating target tissue within a carotid septum of a patient, the method comprising:
 advancing an expandable balloon into a vessel adjacent a carotid septum and expanding the balloon into contact with the vessel;   positioning a cryoablation element within the vessel adjacent the carotid septum; and   cryoablating tissue in the carotid septum using the cryoablation element.   
     
     
         11 . A carotid septum ablation catheter, comprising:
 a deployable arm and an expandable balloon disposed at a distal region of the catheter, the catheter adapted and configured to support a cryoablation element, wherein the deployable arm is configured to engage a wall of an internal carotid artery when the expandable balloon and cryoablation element are disposed in an external carotid artery.   
     
     
         12 . A cryo-ablation catheter adapted to be advanced towards a bifurcation of an internal carotid artery and an external carotid artery, comprising:
 a first arm configured to engage with a wall of the internal carotid artery delimiting a carotid septum, and a second arm configured to be simultaneously engaged with a wall of the external carotid artery delimiting the carotid septum, the first and second arms configured to carry a cryogen fluid to ablate at least a portion of the carotid septum.