Apparatuses for renal neuromodulation

Abstract

Methods and apparatus are provided for renal neuromodulation using a pulsed electric field to effectuate electroporation or electrofusion. It is expected that renal neuromodulation (e.g., denervation) may, among other things, reduce expansion of an acute myocardial infarction, reduce or prevent the onset of morphological changes that are affiliated with congestive heart failure, and/or be efficacious in the treatment of end stage renal disease. Embodiments of the present invention are configured for percutaneous intravascular delivery of pulsed electric fields to achieve such neuromodulation.

1 . Apparatus for renal neuromodulation, the apparatus comprising: 
 a device comprising an electrode, wherein the electrode is configured for percutaneous placement proximate a renal vasculature in a patient; an electric field generator operatively coupled to the electrode; and    a controller configured to operate instructions that cause the electric field generator to deliver an electric field via the electrode to a renal nerves while the electrode is located proximate the renal vasculature.    
   
   
       2 . The apparatus of  claim 1  wherein 
 the electrode is configured for placement within the renal vasculature.    
   
   
       3 . The apparatus of  claim 2  wherein the device further comprises a catheter configured for advancement within the renal vasculature, and 
 wherein the electrode is carried by the catheter.    
   
   
       4 . (canceled)  
   
   
       5 . The apparatus of  claim 2  wherein the device is configured to be arranged in (a) a reduced delivery configuration for movement within the patient, and (b) an expanded treatment configuration for delivering the electric field to the renal nerves.  
   
   
       6 . The apparatus of  claim 2  wherein the electrode is configured to physically contact a wall of the renal vasculature.  
   
   
       7 . The apparatus of  claim 6  wherein the electrode is chosen from the group consisting of expandable helical electrodes, expandable ring electrodes, expandable basket electrodes, expandable point contact electrodes and combinations thereof.  
   
   
       8 . The apparatus of  claim 2  wherein the device further comprises an expandable centering element configured to physically contact a wall of the renal vasculature.  
   
   
       9 . The apparatus of  claim 8  wherein the expandable centering element is chosen from the group consisting of inflatable balloons, expandable baskets and combinations thereof.  
   
   
       10 . The apparatus of  claim 8  wherein the electrode is located on the expandable centering element and configured to physically contact the wall of the renal vasculature.  
   
   
       11 . (canceled)  
   
   
       12 . The apparatus of  claim 8  wherein the device further comprises a shaft longitudinally aligned with the centering element and the electrode is located on the shaft.  
   
   
       13 . The apparatus of  claim 8 , wherein the electrode comprises a first electrode located proximal of the centering element and the device further comprises a second electrode located distal of the centering element, and wherein the first and second electrodes are a bipolar electrode pair.  
   
   
       14 . The apparatus of  claim 8  wherein the centering element is configured to electrically insulate a segment of the renal vasculature and direct the electric field to the renal nerves.  
   
   
       15 . The apparatus of  claim 2  wherein the electrode is a first electrode and the device further comprises a catheter having a guide wire lumen and a second electrode configured for movement through the guide wire lumen.  
   
   
       16 . The apparatus of  claim 15  wherein the second electrode is electrically coupled to the pulsed electric field generator and is configured for use in a bipolar fashion with the first electrode of the device.  
   
   
       17 . The apparatus of  claim 1 , wherein the electrode comprises a first electrode and the device further comprises a second electrode to define a bipolar electrode pair.  
   
   
       18 . The apparatus of  claim 1  wherein the electrode comprises a dynamically controllable electrode.  
   
   
       19 . The apparatus of  claim 1  wherein the controller is configured to operate instructions that cause the electric field generator to deliver a stimulation electric field to the renal nerve.  
   
   
       20 . The apparatus of  claim 1  wherein the device is configured to controllably move the electrode radially relative to a wall of the renal vasculature.  
   
   
       21 . (canceled)  
   
   
       22 . The apparatus of  claim 1  wherein the electrode is configured for partial or complete passage across a wall of the renal vasculature.  
   
   
       23 . The apparatus of  claim 1  wherein the electrode is configured to at least partially encircle a renal artery of the patient.  
   
   
       24 . The apparatus of  claim 1 , further comprising an infusion element configured to infuse agents proximate the renal vasculature.  
   
   
       25 . The apparatus of  claim 24  wherein the infusion element is configured to create a working space for advancement of the electrode.  
   
   
       26 . The apparatus of  claim 1 , wherein the electrode comprises an active electrode, and the device further comprises a return electrode that together define a bipolar electrode pair in which at least one of the active electrode and the return electrode is configured for dynamic movement to vary a longitudinal separation distance between the active and return electrodes of the bipolar electrode pair.  
   
   
       27 . The apparatus of  claim 1 , wherein the device is configured for infusion or aspiration.  
   
   
       28 . The apparatus of  claim 1  wherein the device further comprises a monitoring element for monitoring the response of at least one physiological parameter to treatment of the renal nerves.  
   
   
       29 . The apparatus of  claim 28  wherein the monitoring element is chosen from the group consisting of Doppler ultrasound sensors, thermocouples, pressure sensors, imaging modalities, electrical impedance sensors and combinations thereof.  
   
   
       30 . The apparatus of  claim 1  wherein the device is configured to orient a longitudinal portion of the electric field with a longitudinal dimension of at least one of the renal nerves and the renal vasculature.  
   
   
       31 . The apparatus of  claim 1  wherein the electrode comprises an active electrode and the device further comprises a ground electrode configured for exterior attachment to the patient such that the active electrode is configured to deliver the pulsed electric field to the renal nerves in a monopolar fashion.  
   
   
       32 - 61 . (canceled)  
   
   
       62 . The apparatus of  claim 1  wherein the controller is configured to operate instructions that cause the electric field generator to deliver a thermal electric field to the renal nerve.  
   
   
       63 . The apparatus of  claim 1  wherein the controller is configured to operate instructions that cause the electric field generator to deliver an electric field that induces a condition in the renal nerve selected from the group consisting of electroporation, electrofusion, thermal alteration, ablation, necrosis, apoptosis, and combinations thereof.  
   
   
       64 . The apparatus of  claim 1  wherein the controller is configured to operate instructions that cause the electric field generator to deliver a pulsed electric field that induces a condition in the renal nerve selected from the group consisting of electroporation, electrofusion, thermal alteration, ablation, necrosis, apoptosis, and combinations thereof.  
   
   
       65 . The apparatus of  claim 1  wherein the electric field generator is configured to deliver radio frequency energy via the electrode to the renal nerve.  
   
   
       66 . The apparatus of  claim 1  wherein the electric field generator is configured to deliver microwave energy via the electrode to the renal nerve.  
   
   
       67 . The apparatus of  claim 1  wherein the electric field generator is configured to deliver ultrasound energy via the electrode to the renal nerve.  
   
   
       68 . The apparatus of  claim 67  wherein the ultrasound energy is high intensity focused ultrasound.  
   
   
       69 . The apparatus of  claim 3  wherein the device further comprises a sheath configured to facilitate advancement of the catheter.  
   
   
       70 . The apparatus of  claim 69  wherein the device further comprises a thermocouple for monitoring temperature.  
   
   
       71 . The apparatus of  claim 3  wherein the catheter comprises a proximal section and a distal section, and wherein the electric field generator is electrically coupled to the proximal section and the electrode is coupled to the distal section.  
   
   
       72 . The apparatus of  claim 11  wherein the electrode is configured to remain out of contact with the wall of the renal vasculature.  
   
   
       73 . The apparatus of  claim 20  wherein the controller is further configured to operate instructions that cause the electric field generator to deliver the thermal electric field in a manner that at least partially ablates the renal nerve.  
   
   
       74 . The apparatus of  claim 20  wherein the controller is further configured to operate instructions that cause the electric field generator to deliver the thermal electric field in a manner that at least partially denervates renal tissue of the patient.  
   
   
       75 . The apparatus of  claim 28  wherein the controller is configured to operate instructions that cause the electric field generator to modulate delivery of the electric field in response to the monitored physiological parameter.  
   
   
       76 . Apparatus for renal denervation, the apparatus comprising: 
 an electrode configured for placement within a renal vasculature in a patient,    an electric field generator operatively coupled to the electrode; and    a controller configured to operate instructions that cause the electric field generator to deliver an electric field via the electrode to a renal nerve while the electrode is located within the renal vasculature.    
   
   
       77 . The apparatus of  claim 76 , further comprising a catheter configured for advancement within the renal vasculature, wherein the electrode is carried by the catheter.  
   
   
       78 . The apparatus of  claim 76  wherein the controller is configured to operate instructions that cause the electric field generator to deliver a thermal electric field to the renal nerve.  
   
   
       79 . The apparatus of  claim 78  wherein the controller is further configured to operate instructions that cause the electric field generator to deliver the thermal electric field in a manner that at least partially ablates the renal nerve.  
   
   
       80 . The apparatus of  claim 78  wherein the controller is further configured to operate instructions that cause the electric field generator to deliver the thermal electric field in a manner that at least partially denervates renal tissue of the patient.  
   
   
       81 . The apparatus of  claim 76  wherein the controller is configured to operate instructions that cause the electric field generator to deliver an electric field that induces a condition in the renal nerve selected from the group consisting of electroporation, electrofusion, thermal alteration, ablation, necrosis, apoptosis, and combinations thereof.