The invention relates to a device and a method for the removal of a heart valve stenosis, in which a filter catheter is arranged in a vessel section located downstream of the heart valve, and a valvuplasty catheter is arranged in the area of the heart valve. The filter catheter has in one embodiment of the invention at its distal end a radial filter which is unfolded radially until it fits up against the vessel wall. The catheter lumen is closed in such a way that blood must flow through the filter. After the filter has been unfolded, the valvuplasty catheter is inflated in the area of the heart valve to remove the heart valve stenosis, while debris and plaque which are released are collected in the filter. In an alternative membrane, the filter catheter may be sealed relative to the vessel wall by means of a sealing element, while an external filter is connected to the filter catheter to filter debris and plaque from the blood.