The techniques for sealing with the Tissucol fibrin glue, used in repair of aortic dissections and aneurysms, are described. We applied this method to 24 patients operated upon for acute (9 cases) or chronic (15 cases) lesions of the thoracic aorta. No patients died of haemorrhage, and post-operative bleeding was only 500 ml on average. Provided strict precautions are taken, this adjuvant haemostatic method considerably improves the immediate prognosis of acquired aortic lesions. Other operations of cardiac surgery may benefit from these sealing techniques the cost of which must be weighed against the blood transfusion units that are saved.