Three cases of unexpected clinical course of ruptured aortic aneurysm have been presented in patients of their 7th decade life. All of them had arterial hypertension. Signs and symptoms on admission to hospital (dysphagia, chest and interscapular pain, hematemesis, abdominal pain, elevated body temperature and diminished exercise tolerance) were non-specific of aortic aneurysm, suggesting other disease. Dramatic clinical course with hypovolemic shock in two cases led to death. One of them refused surgery. In the third one, in spite of blood effusions to pleural cavity, pericardial sac and mediastinum, effective hypotensive therapy with a preservation of the slow heart rate and fluid evacuation from pericardial sac, gave the opportunity to perform elective surgery. Aortic dissection often presents an atypical course and when suspected, all available imaging technics including computed tomography and nuclear magnetic resonance must be used.