Apparatus for thermal modulation of nerves contributing to renal function

Abstract

Methods and apparatus are provided for treatment of heart arrhythmia via renal neuromodulation. Such neuromodulation may effectuate irreversible electroporation or electrofusion, ablation, necrosis and/or inducement of apoptosis, alteration of gene expression, action potential attenuation or blockade, changes in cytokine up-regulation and other conditions in target neural fibers. In some embodiments, such neuromodulation is achieved through application of an electric field. In some embodiments, such neuromodulation is achieved through application of neuromodulatory agents, of thermal energy and/or of high intensity focused ultrasound. In some embodiments, such neuromodulation is performed in a bilateral fashion.

1 - 48 . (canceled) 
   
   
       49 . An apparatus for thermal modulation of nerves that contribute to renal function via thermal ablation of tissue, the apparatus comprising:
 an elongate shaft configured for intravascular delivery through vasculature and placement within a renal blood vessel;   a thermal neuromodulation element coupled to a distal portion of the elongate shaft and configured for placement against an interior wall of the renal blood vessel proximate to nerves that contribute to renal function, wherein the thermal ablation element is further configured to thermally ablate the nerves from within the renal blood vessel;   a sensor proximate to the thermal neuromodulation element and configured to monitor a parameter comprising at least one of temperature and impedance; and   means for minimizing thermal damage to the interior wall of the renal blood vessel based on the monitored parameter.   
   
   
       50 . The apparatus of  claim 49  wherein the thermal neuromodulation element comprises a distal expandable section configured to expand from a low profile configuration to a wall contact configuration. 
   
   
       51 . The apparatus of  claim 50  wherein the distal expandable section comprises an expandable linkage system. 
   
   
       52 . The apparatus of  claim 50  wherein the distal expandable section comprises a helical section. 
   
   
       53 . The apparatus of  claim 52  wherein the helical section is configured to create multiple ablation zones and minimize circumferential overlap of adjacent ablation zones. 
   
   
       54 . The apparatus of  claim 52  wherein the helical section comprises an electrode. 
   
   
       55 . The apparatus of  claim 52  wherein the helical section comprises a plurality of electrodes spaced apart along the helical section. 
   
   
       56 . The apparatus of  claim 55  wherein the plurality of electrodes are configured for dynamic operation to create multiple zones of ablation. 
   
   
       57 . The apparatus of  claim 50  wherein the distal expandable section comprises a balloon configured to apply cryogenic treatment to the interior wall of the renal blood vessel. 
   
   
       58 . The apparatus of  claim 50  wherein the distal expandable section is self expandable. 
   
   
       59 . The apparatus of  claim 50  wherein the distal expandable section is mechanically expandable. 
   
   
       60 . The apparatus of  claim 49  wherein the thermal neuromodulation element is configured to thermally ablate the nerves from within the renal blood vessel using radiofrequency energy. 
   
   
       61 . The apparatus of  claim 49  wherein the thermal neuromodulation element is configured to thermally ablate the nerves from within the renal blood vessel using microwave energy. 
   
   
       62 . The apparatus of  claim 49  wherein the thermal neuromodulation element is configured to thermally ablate the nerves from within the renal blood vessel using ultrasound energy. 
   
   
       63 . The apparatus of  claim 49  wherein the sensor comprises a first sensor, and wherein the apparatus further comprises a second sensor. 
   
   
       64 . The apparatus of  claim 63  wherein the second sensor is at least one of a Doppler element, thermocouple, pressure sensor, or impedance sensor.