Apparatus and Methods for Ablation Efficacy

Abstract

Apparatus and methods for ablation efficacy are described herein where a hood having a deployable elongated feature can extend beyond a distal face of the hood. The elongated feature can channel the energy to the deeper regions within the tissue (such as trabeculated regions or other tissue structures) such that the energy can be delivered to the target tissue despite small or large irregularities in the target tissue surface (or region) and/or changes in the relative distances between the hood and the target tissue.

1 - 20 . (canceled) 
     
     
         21 . A method of ablating a tissue region having irregular anatomy, comprising:
 positioning a catheter in proximity to the tissue region;   reconfiguring a non-inflatable hood attached to the distal end of the catheter from a low-profile shape into a deployed shape, wherein the hood defines an open area when in the deployed shape which is in fluid communication through at least one opening with an environment external to the hood;   introducing a clearing fluid into the open area such that an opaque fluid is purged from the open area and through the at least one opening into the environment;   energizing the clearing fluid via at least one electrode; and   dispersing the clearing fluid while passing into the environment via a fluid dispersing feature.   
     
     
         22 . The method of  claim 21  wherein reconfiguring comprises self-expanding the non-inflatable hood from the low-profile shape to the deployed shape. 
     
     
         23 . The method of  claim 21  wherein introducing comprises introducing saline fluid into the open area. 
     
     
         24 . The method of  claim 21  wherein energizing comprises energizing the clearing fluid via RF energy. 
     
     
         25 . The method of  claim 21  further comprising visualizing the tissue region via an imaging element while energizing the clearing fluid. 
     
     
         26 . The method of  claim 21  wherein dispersing comprises dispersing the fluid with the fluid dispersing feature which defines a plurality of openings therethrough. 
     
     
         27 . The method of  claim 21  wherein dispersing comprises dispersing the fluid with the fluid dispersing feature, the fluid dispersing feature comprising a domed or cylindrical structure. 
     
     
         28 . The method of  claim 21  wherein dispersing comprises dispersing the fluid with the fluid dispersing feature, the fluid dispersing feature comprising an electrically conductive material. 
     
     
         29 . The method of  claim 25  wherein the imaging element is positioned within or adjacent to the non-inflatable hood. 
     
     
         30 . The method of  claim 21  wherein introducing comprises introducing the clearing fluid prior to, during, or after visualizing the tissue region. 
     
     
         31 . The method of  claim 21  wherein the non-inflatable hood comprises one or more struts that provide structural support. 
     
     
         32 . The method of  claim 21  wherein reconfiguring further comprises providing a permeable feature over the at least one opening. 
     
     
         33 . The method of  claim 32  wherein the permeable feature comprises a screen, mesh, grating, or porous membrane. 
     
     
         34 . The method of  claim 21  wherein the fluid dispersing feature is energized or charged via the one or more struts. 
     
     
         35 . The method of  claim 21  wherein the catheter comprises an electrode tip. 
     
     
         36 . The method of  claim 21  wherein a slidable sheath surrounds the at least one electrode. 
     
     
         37 . The method of  claim 36  wherein the slidable sheath is independently controlled relative to the at least one electrode.