Cardiac ablation system and method for treatment of cardiac arrhthmias and transmyocardial revascularization

Abstract

A medical device, and related method, use epicardial ablators and detectors for intraoperative epicardial approaches to ablation therapy of cardiac conduction pathways. An epicardial gripper is sized to grasp the cardiac circumference or smaller structures on the epicardial surface of the heart. Ablators are disposed on the arms of the gripper for epicardial ablation of cardiac conduction tissue. In another embodiment of the invention, an electrode system includes a flexible, adjustable probe forming a loop for epicardial ablation. Ablators are provided on one or multiple surfaces of the probe for epicardial ablation of cardiac conduction tissue. In yet another embodiment of the invention, an endocardial ablator detection system provides an indicator adjacent an ablator on an endocardial catheter, and a detector on an epicardial probe. The epicardial probe detects signals transmitted by the indicator on the endocardial catheter to localize the position of the endocardial ablator relative to the epicardial surface. The surgeon uses this information for guidance in adjusting the position of the endocardial ablator according to therapeutic objectives of cardiac ablation.

1 . A method of treating cardiac arrhythmia using epicardial ablation comprising the steps of 
 providing a gripper device having a plurality of arms, each arm having an inner surface and an outer surface, wherein at least one of said arms is moveable relative to the other arm, the gripper device also having an ablator disposed on said inner surface of at least one of said moveable arms;    gripping an epicardial surface of the heart with the gripper device to position the ablator in contact with at least a portion of the heart along a circumference of the heart; and    applying said ablator to said epicardial surface at least once such that cardiac conductive tissue is ablated to create a lesion that encircles the heart.    
     
     
         2 . The method of  claim 1 , wherein the step of applying said ablator comprises applying RF energy to said epicardial surface.  
     
     
         3 . The method of  claim 1 , wherein the step of applying said ablator comprises applying laser energy to said epicardial surface.  
     
     
         4 . The method of  claim 1 , wherein the step of applying said ablator comprises applying ultrasonic energy to said epicardial surface.  
     
     
         5 . The method of  claim 2 , wherein the step of applying said ablator comprises applying RF energy to said epicardial surface using a plurality of ablators disposed on said inner surface of at least two arms.  
     
     
         6 . The method of  claim 3 , wherein the step of applying said ablator comprises applying laser energy to said epicardial surface using a plurality of ablators disposed on said inner surface of at least two arms.  
     
     
         7 . The method of  claim 4 , wherein the step of applying said ablator comprises applying ultrasonic energy to said epicardial surface using a plurality of ablators disposed on said inner surface of at least two arms.  
     
     
         8 . A gripping apparatus for treating cardiac arrhythmia which forms encircling lesions upon an epicardial surface, the apparatus comprising 
 at least two moveable arm members, each moveable arm member having an inner and outer surface and at least one ablator on each of the moveable arm members;    wherein each moveable arm member is curved such that each moveable arm member may contact at least a curved portion of a circumference of a heart.    
     
     
         9 . A gripping apparatus for treating cardiac arrhythmia which forms encircling lesions upon an epicardial surface, the apparatus comprising 
 at least two moveable arm members, each moveable arm member having an inner and outer surface and at least one ablator on each of the moveable arm members; and    an epicardial detector to assist in positioning the gripping apparatus for an ablation treatment;    wherein each moveable arm member is curved such that each moveable arm member may contact at least a curved portion of a circumference of a heart.    
     
     
         10 . The gripping apparatus of  claim 9 , wherein the epicardial detector comprises an ultrasound probe located on the inner surface of a first moveable arm member of said at least two moveable arm members to assess contact between the first moveable arm member and a surface of the heart.  
     
     
         11 . The gripping apparatus of  claim 9 , wherein said at least two moveable arm members comprises a first moveable arm member and a second moveable arm member pivotally coupled such that the inner surfaces of the first and second moveable arm members face each other and form a substantially closed loop.  
     
     
         12 . The gripping apparatus of  claim 9 , wherein the number of moveable arm members is two, and wherein the inner surfaces of the moveable arms face each other and are positioned such that they substantially encircle a circumference of the heart.  
     
     
         13 . An apparatus for treating cardiac arrhythmia which forms encircling lesions upon an epicardial surface, the apparatus comprising 
 a substrate forming a substantially closed loop, the substrate having an inner surface and an outer surface;    at least one ablator on the inner surface; and    an epicardial detector to assist in positioning the apparatus for an ablation treatment;    wherein the substrate is curved such that it can contact at least a curved portion of a circumference of a heart.    
     
     
         14 . The apparatus of  claim 13 , wherein the epicardial detector comprises an ultrasound probe located on the inner surface to assess contact between the substrate and a surface of the heart.  
     
     
         15 . The apparatus of  claim 13 , wherein the substrate is flexible and adjustable to form loops of different sizes.  
     
     
         16 . The apparatus of  claim 13 , wherein said at least one ablator comprises a plurality of ablators that are arranged on the substrate to create an ablation site interior to the substantially closed loop.  
     
     
         17 . The apparatus of  claim 13 , further comprising a suction device to help maintain contact between the at least one ablator and the epicardial surface.