Methods of coagulating tissue

Abstract

An embodiment of the invention includes a surgical device for coagulating soft tissue such as atrial tissue in the treatment of atrial fibrillation, atrial flutter, and atrial tachycardia; tendon or ligament shrinkage; or articular cartilage removal. The surgical device integrates a suction mechanism with the coagulation mechanism improving the lesion creation capabilities of the device. The surgical device comprises an elongate member having an insulative covering attached about conductive elements capable of coagulating soft tissue when radiofrequency or direct current energy is transmitted to the conductive elements. Openings through the insulative covering expose regions of the conductive elements and are coupled to lumens in the elongate member which are routed to a vacuum source. Suction causes the soft tissue to actively engage the opening thus the integrated, exposed conductive elements to facilitate the coagulation process and ensure the lesions created are consistent, continuous, and transmittal. The embodiments of the invention can also incorporate cooling mechanisms associated with the conductive elements and coupled to a fluid source to passively transport fluid along the contacted soft tissue surface to cool thus pushing the maximum temperature deeper into tissue.

We claim: 
     
         1 . A method for creating a lesion in a length of soft tissue, the method comprising:
 placing an elongate member against the soft tissue, the elongate member composing a side wall, at least one first lumen, at least one conductive element attached to said side wall, and at least one opening through said side wall coupled to said lumen and exposing said conductive element against a soft tissue surface such that said opening engages said soft tissue surface;   applying a vacuum source to said first lumen causing said soft tissue to contact said conductive element;   where the opening further comprises a flexible extension about the opening that is adapted to deform to sealingly engage the soft tissue when applying the vacuum source; and   transmitting energy to said conductive element to cause electroporation in the soft tissue.   
     
     
         2 . The method of  claim 1  wherein said elongate member is malleable and the step of placing said elongate member opening against said soft tissue surface comprises deforming said elongate member before or after advancing said opening against said soft tissue surface. 
     
     
         3 . The method of  claim 1  further comprising an injection support tube attached to said side wall of said elongate member, wherein said injection support tube comprises a second lumen and said step of placing said elongate member against the soft tissue comprises inserting a stylette through said second lumen to reshape said elongate member. 
     
     
         4 . The method of  claim 1  further comprising an injection support tube attached to said side wall of said elongate member; wherein said injection support tube comprises a second lumen coupled to said first lumen and said step applying vacuum to said first lumen causes said fluid to pass through said second lumen and said first lumen. 
     
     
         5 . The method of  claim 1  wherein said soft tissue is atrium and said opening contacts the epicardial surface. 
     
     
         6 . The method of  claim 1 , where a portion of the sidewall comprises the flexible extension. 
     
     
         7 . The method of  claim 1 , where a portion of the sidewall comprises the flexible extension. 
     
     
         8 . A surgical device for coagulating soft tissue comprising:
 a first elongate member comprising to side wall with at least one lumen and at least one conductive element attached to said side wall; at least one opening through said side wall of said first elongate member, said opening coupled to said lumen and exposing said conductive element, where said element is configured to apply energy to cause electroporation of tissue,   where the conductive element is recessed from the opening and the opening comprises a flexible portion capable of deforming to sealingly form against the soft tissue,   where the opening allows soft tissue to be pulled through the opening to contact the conductive element; and wherein said conductive element comprises at least one helical winding having at least one pitch and at least one winding width.   
     
     
         9 . The device of  claim 8 , where a portion of the first elongate member containing the conductive element and the conductive element are deformable. 
     
     
         10 . The device of  claim 9 , where the portion of the first elongate member containing the conductive element and the conductive element are elastic. 
     
     
         11 . The device of  claim 9 , where the portion of the first elongate member containing the conductive element and the conductive element are malleable. 
     
     
         12 . The device of  claim 8 , wherein said side wall comprises an insulator covering. 
     
     
         13 . The device of  claim 8 , wherein said conductive element comprises a series of helical windings having at least one pitch and at least one winding width; wherein said pitch is greater than or equal to two times said width. 
     
     
         14 . The device of  claim 8 , wherein said conductive element comprises a series of helical windings having at least one pitch and at least one winding width, wherein said pitch is greater than or equal to four times said width. 
     
     
         15 . The device of  claim 8  wherein the external surface of said side all along said opening is offset from said conductive element by a distance; wherein the width of said opening is greater than or equal to said offset distance. 
     
     
         16 . The device of  claim 8  wherein the external surface of said side wall along said opening is offset from said conductive element by a distance; wherein the width of said opening is greater than two times said offset distance.