Ablation Catheter

Abstract

An ablation catheter apparatus with a monopole antenna that is arranged to provide a relatively uniform electric field and a method for using such an ablation catheter apparatus are disclosed. According to one aspect of the present invention, an ablation catheter includes an elongated flexible tubular member that is adapted to be inserted into the body of a patient, and a transmission line that is disposed within the tubular member. The transmission line has a distal end and a proximal end which is arranged to be connected to an electromagnetic energy source. The catheter also includes a monopole antenna with tip section and a body section that includes a distal end and a proximal end. The tip section and the body section are arranged to produce a relatively uniform electric field around the monopole antenna which is sufficiently strong to cause tissue ablation. The proximal end of the body-section of the monopole antenna is arranged to be electrically coupled to the transmission line.

1 . An ablation device for ablating biological tissue, comprising:
 an elongated tubular member configured to be inserted into a patient's body and having a distal end;   an ablation device attached to the distal end of the tubular member having an outer surface through one portion of which ablation energy passes; and   a sensor electrode disposed on another portion of the outer surface of the ablation device spaced from the one portion of the outer surface through which ablation energy passes, the sensor electrode being disposed to contact tissue and sense electro-physiological signals therein.   
   
   
       2 . The ablation device of  claim 1  in which the ablation device includes an antenna disposed within a tip of bioinert and electrically insulative material having said outer surface for radiating electromagnetic energy through said one portion of the outer surface; and
 said sensor electrode is disposed on the outer surface of the tip distally of said one portion.   
   
   
       3 . The ablation device of  claim 2  including an additional sensor electrode disposed on the outer surface away from the sensor electrode and from said one portion for contacting tissue to sense electro-physiological signals therein. 
   
   
       4 . The ablation device of  claim 2  in which the antenna includes a monopole structure configured for emitting a substantially uniform electromagnetic field through said one portion of the outer surface in response to microwave electrical energy supplied to the antenna. 
   
   
       5 . The ablation device of  claim 4  in which the tubular member is flexible and the tip attached at the distal end of the tubular member maintains selected shape of the outer surface supporting the sensor electrodes.