An ablation applicator for an ablation device for ablating tissue of a blood vessel having a tubular body defining an inner lumen to which an ablation medium is conductable, a control mechanism for converting the tubular body between a passive operation mode for inserting the ablation applicator into the blood vessel and an active operation mode for ablating tissue of the blood vessel, and an ablation medium supply line for supplying the ablation medium to the inner lumen and positioned within the inner lumen and having a number of openings for passing the ablation medium from the ablation medium supply line to the inner lumen for thermally contacting the ablation medium with the tubular body wherein at least some of the openings are distributed along the ablation medium supply line with a predetermined spacing between neighboring openings. The ablation device can include a first temperature sensor arranged within the inner lumen and an ablation medium return line inside the tubular body made from a material that defines the active shape of the applicator.
