Ablation catheter with a balloon (3), the catheter comprising: a shaft (2, 2a-g) formed from a single tube, two lumens that communicate from a distal end to a proximal end of the shaft, wherein the first lumen is a lumen for passage of the guide wire (5a-h) arranged to allow a guidewire (14) to pass therethrough, the second lumen is a lumen for supplying liquid (6a-h ) arranged to supply a liquid heating into the balloon (3), an electrode (4) attached to the shaft within the balloon (3), a temperature sensor (7) for measuring the temperature in the balloon joins the electrode (4), at least one conductor cable radio frequency carrier (8) connected to the electrode (4) and a lead wire temperature (9) sensor connected to the temperature sensor (7), wherein the conductor cable the temperature sensor passes through the lumen for the supply of liquid (6a-h), wherein a leng d The a contour of a shape of the lumen for delivering fluid (6a-h) in a direction perpendicular to a longitudinal direction of the single tube cross section refers to the total length of an inner circumference of the lumen for the supply of liquid ( 6a-h), an outer circumference of each conductor cable radio frequency carrier (8) and an outer circumference of lead wire of the temperature sensor (9), and a length Li is a circumference of a circle having an area equal to a area of a lumen for the supply of liquid surrounded by the contour, wherein each conductive wire carrier radio frequency passes through the lumen for the supply of liquid (6a-h), the value La / Li is 1 to 2, 3 and the lumen area for the liquid supply is surrounded by the outline of 2.0 to 4.5 mm2.Catéter de ablación con un balón (3), comprendiendo el catéter: un eje (2, 2a-g) formado a partir de un único tubo, dos lúmenes que se comunican desde un extremo distal hasta un extremo proximal del eje, en el que el primer lumen es un lumen para el paso del alambre de guía (5a-h) dispuesto para permitir que un alambre de guía (14) pase a tr
