Circumferential ablation device assembly

Abstract

This invention is a circumferential ablation device assembly which is adapted to forming a circumferential conduction block in a pulmonary vein. The assembly includes a circumferential ablation element which is adapted to ablate a circumferential region of tissue along a pulmonary vein wall which circumscribes the pulmonary vein lumen, thereby transecting the electrical conductivity of the pulmonary vein against conduction along its longitudinal axis and into the left atrium. The circumferential ablation element includes an expandable member with a working length that is adjustable from a radially collapsed position to a radially expanded position. An equatorial band circumscribes the outer surface of the working length and is adapted to ablate tissue adjacent thereto when actuated by an ablation actuator. The equatorial band has a length relative to the longitudinal axis of the expandable member that is narrow relative to the working length, and is also substantially shorter than its circumference when the working length is in the radially expanded position. A pattern of insulators may be included over an ablation element which otherwise spans the working length in order to form the equatorial band described. The expandable member is also adapted to conform to the pulmonary vein in the region of its ostium, such as by providing a great deal of radial compliance or by providing a taper along the working length which has a distally reducing outer diameter. A linear ablation element is provided adjacent to the circumferential ablation element in a combination assembly which is adapted for use in a less-invasive “maze”-type procedure in the region of the pulmonary vein ostia in the left ventricle.

1 - 62 . (canceled)  
   
   
       63 . A tissue ablation device assembly, comprising: 
 an ablation member adapted to be positioned at a location where a pulmonary vein extends from an atrium and to simultaneously ablate a circumferential region of tissue at the location.    
   
   
       64 . A tissue ablation device assembly as recited in  claim 63 , wherein the ablation member includes an ablation element.  
   
   
       65 . A tissue ablation device assembly as recited in  claim 64 , wherein the ablation member comprises an ablation element, and the ablation member is adapted to position the ablation element generally at a central position at the location relative to a lumenal axis of the pulmonary vein.  
   
   
       66 . A tissue ablation device assembly as recited in  claim 64 , wherein the ablation member includes a conductive fluid delivery source which is adapted to occupy at least a portion of a space between the ablation element and the region of tissue.  
   
   
       67 . A tissue ablation device assembly as recited in  claim 63 , wherein the ablation member comprises an ablation element which is adapted to contact the region of tissue.  
   
   
       68 . A tissue ablation device assembly as recited in  claim 63 , wherein the ablation member comprises a delivery mechanism to deliver an ablative fluid to the circumferential region of tissue.  
   
   
       69 . A tissue ablation device assembly comprising an ablation member with an ablation element adapted to ablate a circumferential region of tissue without substantially repositioning the ablation element.  
   
   
       70 . A tissue ablation device assembly as recited in  claim 69 , wherein the ablation member is adapted to inhibit blood from contacting the region of tissue when the ablation element is ablatively coupled to the region of tissue.  
   
   
       71 . A tissue ablation device assembly as recited in  claim 70 , wherein the ablation member is adapted to substantially prevent blood from contacting the region of tissue when the ablation element is ablatively coupled to the region of tissue.  
   
   
       72 . A tissue ablation device assembly comprising an ablation member adapted to be positioned within a vessel having a lumen having a diameter of greater than approximately 1.5 centimeters and to ablate a circumferential region of tissue of the vessel of a sufficient depth so as to form a conduction block along a length of the vessel.  
   
   
       73 . A tissue ablation device assembly as recited in  claim 72 , wherein the ablation member comprises a delivery mechanism to deliver an ablative fluid to the circumferential region of tissue.