A catheter includes a tubular body having a channel having its ends opening out respectively at the ends of the tubular body, injector element for injecting fluid into the channel, a tubular endpiece having a channel with ends opening out respectively at the ends of the tubular endpiece, and element for connecting the endpiece and the body together so that the end of the channel and the end of the channel are in alignment on an axis, the connection element being constituted essentially by a ring that partially covers the body and the endpiece, and being also arranged in such a manner that the connection can be broken by exerting a force couple of predetermined value respectively on the endpiece and on the body. The invention is applicable to safety catheters for performing endovascular treatments by injecting embolic fluid, for example for treating arteriovenous malfunctions.