Two men, aged 71 and 70, who had previously experienced an abdominal aneurysm were found to have thoracic aortal aneurysms of respectively 8 cm and 7.5 cm in length. For the first patient an endovascular operation was carried out due to a high operative risk: with the help of a radiograph, four endoprostheses were inserted into the thoracic descending aorta via the femoral artery, after which the aorta diameter became more normal. A month later, the patient died from persistent renal failure, which had developed as a result of the previously ruptured abdominal aneurysm. In the second patient with an aneurysm of the proximal descending aorta, a left decompensation arose following aortal clamping during open surgical repair. Ten weeks later an endoprosthesis was inserted via the femoral artery. A year later the aortal diameter had decreased to 6.5 cm; the patient functioned well. The insertion of an endoprosthesis in the thoracic aorta is a minimally invasive procedure in which the patient experiences little perioperative inconvenience.