[Atrioventricular block disclosing an isolated congenital aneurysm of the sinus of Valsalva, extending into the septum and not ruptured].

A case of a congenital aneurysm of the right anterior sinus of Valsalva (ASV) extending into the septum is reported. The patient, a 20 year old male Central-African, presented with syncopal complete atrioventricular block (AVB) or recent onset. There were no clinical or radiological signs of associated cardiac disease. After implantation of a pacemaker, the diagnosis of an ASV extending into the septum was suggested on routine M mode echocardiography. It was confirmed by two-dimensional echocardiography and aortography. These investigations provided data on its size, its relationship to the cardiac chambers and also showed absence of rupture. The neck of the aneurysm was closed by an endo-aortic approach. There was moderate postoperative aortic regurgitation. This case underlines the value of systematic echocardiography in young patients with AVB of recent onset and obscure origin.