According to the current invention a medical catheter for plasma ablation within a body cavity is provided, comprising: an elongated catheter having: an input gas lumen an output gas lumen and electrical energy supply cable a gas supply system, supplying gas to the input gas lumen a gas pump, pumping spent gas from the output gas lumen a plasma head at distal end of said elongated catheter and situated in proximity to body part to be ablated, the plasma head comprising: an outer tube defining plasma space between the outer tube and the body part to be ablated, wherein input gas enters the plasma space through the input gas lumen, and spent gas is pumped out of the plasma space through the output gas lumen and a plasma electrode, receiving electrical power from the electrical energy supply cable and generating plasma in the plasma space.
