Ablation catheter and ablation apparatus

Abstract

The present invention relates to an ablation catheter (1) for the ablation of tissues comprising: a telescopic tubular body (4) in turn comprising an external tubular body (4a) and an internal tubular body (4b) concentric with each other, and a rod-like guiding element (5) at least partly housed in the internal tubular body (4b) with at least one free end (5a) protruding from the internal tubular body (4b) in correspondence with a distal end of the telescopic body (4); a positioning head (2, 2″, 2′″, 2°, 2*, 2{circumflex over ( )}) and an ablation head (3) in correspondence with the distal end of the telescopic body (4), the positioning head (2,2″,2″′,2′,2*,2{circumflex over ( )}) being situated in the proximity of the free end (5a) of the rod-like guide, and the ablation head (3) in the proximity of the positioning head (2, 2″, 2″′, 2°, 2*, 2{circumflex over ( )}), in a remote position with respect to the free end (5a); a control handpiece at a proximal end of the telescopic body (4) coupled with the guiding element (5), the ablation head (3), the positioning head (2, 2″, 2′″, 2°, 2*, 2{circumflex over ( )}) and the telescopic tubular body (4); wherein the ablation head (3) comprises at least two ablation elements or petals (3a) that can be moved from a rest position in which they are housed in the external tubular body (4a) and an operating position in which they protrude from the external tubular body (4a) like a petal; wherein each of the ablation elements or petals (3a) comprises: a continuous ablation electrode (3b) which extends without interruption over a circumferential peripheral portion of each petal (3a), substantially along an arc of circumference having a longitudinal axis of the rod-like guiding element (5) as its centre; two side portions (3c) of the petal (3a), each connected to an end of the ablation electrode (3b), in correspondence with a curved section, the side portions (3c) and the ablation electrode (3b) being integral with each other, formed by means of the same folded metallic conductor, each ablation petal (3a) being separate and distinct from another ablation petal (3a) of the ablation head, all the ablation petals (3a) of the ablation head being separately connected to a distinct electric energy generator to cause a radiofrequency ablation and/or a pulsed filed ablation in a powered ablation electrode condition (3b).

1 . A catheter for the ablation of tissues comprising:
 a telescopic tubular body in turn comprising an external tubular body and an internal tubular body concentric with each other, and a rod-like guiding element at least partly housed in the internal tubular body with at least one free end protruding from the internal tubular body in correspondence with a distal end of the telescopic body;   a positioning head and an ablation head in correspondence with the distal end of the telescopic body, the positioning head being situated in the proximity of the free end of the rod-like guide, and the ablation head in the proximity of the positioning head, in a remote position with respect to the free end;   a control handpiece at a proximal end of the telescopic body coupled with the guiding element, the ablation head, the positioning head and the telescopic tubular body;   
       wherein the ablation head comprises at least two ablation elements or petals that can be moved from a rest position in which they are housed in the external tubular body and an operating position in which they protrude from the external tubular body like a petal; 
       each of the ablation elements or petals comprising:
 a continuous ablation electrode which extends without interruption over a circumferential peripheral portion of each petal, substantially along an arc of circumference having a longitudinal axis of the rod-like guiding element as its center; 
 two side portions of the petal, each connected to an end of the ablation electrode, in correspondence with a curved section, 
 
       characterized in that the side portions and the ablation electrode are integral with each other, formed by means of the same folded metallic conductor, each ablation petal being separate and distinct from another ablation petal of the ablation head, all the ablation petals of the ablation head being separately connected to a distinct electric energy generator to cause a radiofrequency ablation and/or a pulsed field ablation in a powered ablation electrode condition and wherein each ablation petal is produced with a single shape-memory metallic conductor wire having a circular section with a diameter D, and, as L is the linear length of the ablation electrode, there is the following ratio D/L ranging from 0.015 to 0.025. 
     
     
         2 . The catheter according to  claim 1 , wherein said ratio D/L is equal to about 0.02. 
     
     
         3 . The catheter according to  claim 1 , wherein the two side portions of each petal are coated with an electrically insulating material, preferably an insulating paint. 
     
     
         4 . The catheter according to  claim 1  comprising, for each petal, at least one conductor which extends as far as the handpiece for individually powering each petal, wherein said conductor extends inside the external body, in the space between this and the internal body, preferably arranged spirally. 
     
     
         5 . The catheter according to  claim 1  comprising, for each petal, at least a first additional conductor at least partly housed in the telescopic tubular body, and destined for preferably extending from the handpiece to the end of the external body. 
     
     
         6 . The catheter according to  claim 1 , wherein each first additional conductor develops spirally inside the external body, and wherein said conductors alternate with at least one additional conductor, inside said external body 
     
     
         7 . The catheter according to  claim 1 , wherein each petal can be moved individually with respect to the others between the rest condition and the extracted, operating condition. 
     
     
         8 . The catheter according to  claim 1 , wherein the ablation petals are rotatingly associated with the telescopic body so that they can be rotated without causing the body and/or the positioning head to also rotate. 
     
     
         9 . The catheter according to  claim 1 , wherein the positioning head comprises at least one extractable positioning arm, said extractable positioning arm being movable between a rest position, in which it is housed in the internal tubular body, and an extracted, operating position, in which it protrudes radially from the internal tubular body. 
     
     
         10 . The catheter according to  claim 1 , wherein the positioning head comprises at least one sensor capable of revealing electric potentials in the tissue and allowing the completeness of the ablation effected, to be revealed. 
     
     
         11 . The catheter according to the previous  claim 9 , wherein said at least one positioning arm is metallic and forms the detection electrode. 
     
     
         12 . The catheter according to  claim 11 , wherein each of said at least one positioning arm is connected to at least one elongated portion which extends as far as the handpiece, housed in the internal body and preferably spiral-shaped. 
     
     
         13 . The catheter according to  claim 12 , wherein second additional conductors are envisaged for the positioning head, which preferably develop spirally and are interspersed with said elongated portions. 
     
     
         14 . An apparatus for the ablation of tissues comprising a catheter according to  claim 1  and at least one electric energy generator for each petal of said catheter, electrically connected to said petal.