Heat transfer through an ablation electrode

Abstract

An apparatus includes a flexible electrically-insulating substrate including an inner surface and an outer surface. The substrate is shaped to define multiple channels passing between the inner surface and the outer surface, at least some of the channels being concave channels. The apparatus further includes an outer layer of an electrically-conducting metal covering at least part of the outer surface, an inner layer of the electrically-conducting metal covering at least part of the inner surface, and respective columns of the electrically-conducting metal that fill the channels such as to connect the outer layer to the inner layer.

What is claimed is: 
     
         1 . An apparatus, comprising:
 a flexible electrically insulative substrate, comprising:
 an inner surface; 
 an outer surface; 
 a first plurality of channels extending between the inner surface and the outer surface, each of the first plurality of channels being configured to direct an irrigation fluid therethrough, and 
 a second plurality of channels extending between the inner surface and the outer surface, each of the second plurality of channels being concave; and 
   an electrically-conductive metal, comprising:
 an outer layer at least partially covering the outer surface; 
 an inner layer at least partially covering the inner surface; and 
 a plurality of columns, each of the second plurality of channels being filled with a corresponding one of the plurality of columns to connect the outer layer to the inner layer. 
   
     
     
         2 . The apparatus of  claim 1 , each of the second plurality of channels comprising:
 a central channel portion; and   at least one peripheral channel portion opening into the central channel portion.   
     
     
         3 . The apparatus of  claim 2 , each central channel portion comprising a circular shape; and
 the peripheral channel portion comprising an arch shape opening into the central channel portion.   
     
     
         4 . The apparatus of  claim 2 , each central channel portion comprising a rectangular shape; and
 the peripheral channel portion comprising a rectangular shape opening into the central channel portion.   
     
     
         5 . The apparatus of  claim 2 , each central channel portion comprising a polygonal shape; and
 the peripheral channel portion comprising a triangular shape opening into the central channel portion.   
     
     
         6 . The apparatus of  claim 1 , a total area of respective outer openings of the first plurality of channels and the second plurality of channels being at least 30% of an area of the outer surface. 
     
     
         7 . The apparatus of  claim 1 , the electrically-conductive metal comprising gold. 
     
     
         8 . The apparatus of  claim 1  further comprising:
 a probe configured for insertion into a body; and 
 a supporting structure attached to the inner layer and coupled to a distal end of the probe. 
 
     
     
         9 . The apparatus of  claim 8 , the supporting structure comprising a plurality of ribs surrounding a lumen. 
     
     
         10 . The apparatus of  claim 9 , successive ribs of the plurality of ribs being separated from one another by an aperture that is wider than each of the ribs. 
     
     
         11 . The apparatus of  claim 1 , a surface of the inner layer being shaped to define a plurality of depressions. 
     
     
         12 . The apparatus of  claim 11 , the plurality of depressions being circular and being arranged in a close-packed pattern. 
     
     
         13 . An apparatus, comprising:
 a substrate, comprising:
 an inner surface; 
 an outer surface; and 
 a plurality of channels extending between the inner surface and the outer surface, each of the plurality of channels being concave; and 
   an electrically-conductive metal, comprising:
 an outer layer at least partially covering at least a part of the outer surface; 
 an inner layer at least partially covering at least a part of the inner surface; and 
 a plurality of columns, each of the plurality of channels being filled with a corresponding one of the plurality of columns to connect the outer layer to the inner layer. 
   
     
     
         14 . The apparatus of  claim 13  further comprising a plurality of irrigation holes extending through the apparatus and configured to direct an irrigation fluid therethrough. 
     
     
         15 . The apparatus of  claim 13 , at least a portion of a surface of the inner layer comprising a plurality of depressions. 
     
     
         16 . The apparatus of  claim 13  further comprising:
 a probe configured for insertion into a body; and 
 a supporting structure attached to the inner layer and coupled to a distal end of the probe. 
 
     
     
         17 . The apparatus of  claim 13 , the apparatus being configured to conduct ablation currents at least via the outer layer. 
     
     
         18 . The apparatus of  claim 13  further comprising a sensor attached to, and electrically insulated from, the inner layer. 
     
     
         19 . The apparatus of  claim 18 , the sensor being configured to acquire physiological readings from tissue. 
     
     
         20 . The apparatus of  claim 13 , each of the plurality of channels comprising:
 a central channel portion; and   at least one peripheral channel portion opening into the central channel portion.