[Echocardiographic diagnosis of aortic dissection. Limits, pitfalls and difficulties].

In patients with suspected dissection of the aorta two-dimensional echocardiography has become a fundamental complementary examination which can easily be used in emergencies. In the light of our experience and of published data, a floating dissected intima is the pathognomonic sign. However, false-negative results have been recorded in about 30% of the cases, as against 10% with angiography, computerized tomography and nuclear magnetic resonance imaging. In spite of this drawback, two-dimensional echocardiography still is a good screening examination, since dissection can almost certainly be excluded when the aorta is of normal caliber. False-positive results also constitute a diagnostic pitfall which must be well known and carefully avoided. The mechanisms of these various problems and the way they can be solved are discussed.