[Right intra-atrial extension of hydatid cyst mimicking cardiac thrombosis. Apropos of a case]. / Extension intra-auriculaire droite d'un kyste hydatique simulant une thrombose cardiaque. A propos d'un cas.

The authors describe an unusual case of hydatid cyst inserted in the inferior vena cava and extending into the right atrium. The transoesoesophageal echocardiographic appearances were similar to those of a thrombus: the tumour was very mobile, echogenic, polylobular with a cord-like pedicle in the inferior vena cava. The pathological examination revealed a ruptured hydatid cyst. The mass and its insertion were not visible on CT scan or cavography. Transoesophageal echocardiography would therefore seem to be a very useful diagnostic method for tumours arising in the inferior vena cava and extending into the right atrium.