Systems and methods for unobstructed visualization and ablation

Abstract

Systems and methods for unobstructed, visualization and ablation, particularly of the pulmonary veins, are described herein. Such a system may include a deployment catheter and an attached imaging hood deployable into an expanded configuration as well as one or more expandable anchors which are temporarily securable within a respective pulmonary vein while allowing blood flow to pass through the anchor unimpeded. With the one or more non-impeding anchors secured within a respective pulmonary vein, ablation of the tissue surrounding the ostium or several ostia may be effected with the catheter while the tissue is under direct visualization.

1 . An apparatus for treating tissue surrounding a vessel opening, comprising:
 a deployment catheter defining at least one lumen therethrough;   a barrier or membrane projecting distally from the deployment catheter and defining an open area therein, wherein the open area is in fluid communication with the at least one lumen;   an anchor having a low-profile shape and an expanded shape, wherein the anchor is sized to be secured at least partially within a vessel lumen in the expanded shape such that blood flows unobstructed through or past the expanded shape; and   an anchor member extending from the anchor and through the catheter wherein a distance of the member between the anchor and the barrier or membrane is adjustable such that the barrier or membrane is positionable directly upon the tissue surrounding the vessel opening.   
   
   
       2 . The apparatus of  claim 1  further comprising a visualization element disposed within or along the barrier or membrane for visualizing tissue adjacent to the open area when the open area is purged of blood via a transparent fluid. 
   
   
       3 . The apparatus of  claim 1  further comprising an ablation probe positionable within the open area of the barrier or membrane. 
   
   
       4 . The apparatus of  claim 1  further comprising an anchor sheath for constraining the anchor in its low-profile shape. 
   
   
       5 . The apparatus of  claim 1  wherein the anchor has a helical configuration. 
   
   
       6 . The apparatus of  claim 1  wherein the anchor has a basket configuration. 
   
   
       7 . The apparatus of  claim 1  wherein the anchor has a meshed configuration. 
   
   
       8 . The apparatus of  claim 1  wherein the anchor comprises a plurality of balloon members which are offset relative to one another along an inflation lumen. 
   
   
       9 . The apparatus of  claim 1  wherein the anchor member extends through the open area within the barrier or membrane. 
   
   
       10 . The apparatus of  claim 1  wherein the anchor member extends through a port defined along the catheter proximal to the barrier or membrane. 
   
   
       11 . An apparatus for treating tissue surrounding a vessel opening, comprising:
 a deployment catheter defining at least one lumen therethrough;   a barrier or membrane projecting distally from the deployment catheter and defining an open area therein, wherein the open area is in fluid communication with the at least one lumen;   a flap member having a low-profile shape and an extended shape, wherein the flap is positioned along an inner surface of the barrier or membrane in its low-profile shape and wherein the flap is projected distally relative to the barrier or membrane in its extended shape, and   wherein the flap member is sized to be positioned at least partially within a vessel lumen in the extended shape such that blood flows unobstructed past the extended flap with the open area positioned upon a portion of the tissue surrounding the vessel opening.   
   
   
       12 . The apparatus of  claim 11  further comprising an inflatable member positioned between the flap and the barrier or membrane. 
   
   
       13 . The apparatus of  claim 11  further comprising a visualization element disposed within or along the barrier or membrane for visualizing tissue adjacent to the open area when the open area is purged of blood via a transparent fluid. 
   
   
       14 . The apparatus of  claim 11  further comprising an ablation probe positionable within the open area of the barrier or membrane. 
   
   
       15 . A method of treating tissue surrounding a vessel opening, comprising:
 intravascularly securing an anchor extending from an anchor member at least partially within a vessel lumen such that blood flows unobstructed through or past the anchor;   adjusting a distance of the anchor member between the anchor and a barrier or membrane projecting distally from a deployment catheter such that an open area defined by the barrier or membrane is placed against or adjacent to a portion of the tissue surrounding the vessel opening;   displacing blood with a transparent fluid from the open area; and   treating the tissue while visualizing through the transparent fluid.   
   
   
       16 . The method of  claim 15  wherein intravascularly securing comprises advancing the anchor within a lumen of a pulmonary vein. 
   
   
       17 . The method of  claim 15  wherein intravascularly securing comprises expanding the anchor from a low-profile shape to an expanded shape. 
   
   
       18 . The method of  claim 15  wherein intravascularly securing comprises expanding the anchor having a helical shape. 
   
   
       19 . The method of  claim 15  wherein intravascularly securing comprises expanding the anchor having a basket shape. 
   
   
       20 . The method of  claim 15  wherein intravascularly securing comprises expanding the anchor having a mesh shape. 
   
   
       21 . The method of  claim 15  wherein adjusting comprises tensioning the anchor member extending through the open area of the barrier or membrane. 
   
   
       22 . The method of  claim 15  wherein adjusting comprises tensioning the anchor member extending through an opening defined along the catheter proximal to the barrier or membrane. 
   
   
       23 . The method of  claim 15  wherein treating comprises ablating the tissue with an ablation probe advanced into the open area. 
   
   
       24 . The method of  claim 15  wherein treating comprises circumferentially ablating the tissue surrounding the vessel opening. 
   
   
       25 . The method of  claim 24  wherein circumferentially ablating comprises ablating the tissue in a continuous line while visualizing through the transparent fluid. 
   
   
       26 . The method of  claim 24  wherein circumferentially ablating comprises ablating the tissue along discrete lesions which overlap one another surrounding the vessel opening. 
   
   
       27 . A method of ablating tissue surrounding a vessel opening, comprising:
 positioning an anchor at least partially within a vessel lumen, wherein the anchor comprises an open structure which allows unobstructed blood flow through or past the anchor;   positioning a barrier or membrane projecting distally from a deployment catheter such that an open area defined by the barrier or membrane is placed against or adjacent to a portion of the tissue surrounding the vessel opening;   purging blood with a transparent fluid from the open area such that the portion of tissue is visualized through the transparent fluid; and   adjusting a position of the barrier or membrane relative to the vessel opening such that the catheter remains tethered to the anchor.   
   
   
       28 . The method of  claim 27  wherein positioning an anchor comprises advancing the anchor within a lumen of a pulmonary vein. 
   
   
       29 . The method of  claim 27  wherein positioning a barrier or membrane comprises tensioning an anchor member connected to the anchor and extending through the open area of the barrier or membrane. 
   
   
       30 . The method of  claim 27  wherein adjusting a position comprises circumscribing tissue surrounding the vessel opening while tethered to the anchor. 
   
   
       31 . The method of  claim 30  wherein circumscribing tissue further comprises visualizing the tissue through the transparent fluid while adjusting the position of the barrier or membrane. 
   
   
       32 . The method of  claim 27  further comprising treating the tissue visualized within the open area. 
   
   
       33 . The method of  claim 32  wherein treating comprises ablating the tissue visualized within the open area. 
   
   
       34 . The method of  claim 33  wherein treating comprises circumferentially ablating the tissue surrounding the vessel opening. 
   
   
       35 . The method of  claim 33  wherein treating comprises circumferentially ablating the tissue in a continuous line while visualizing through the transparent fluid. 
   
   
       36 . The method of  claim 33  wherein circumferentially ablating comprises ablating the tissue along discrete lesions which overlap one another surrounding the vessel opening.