[Idiopathic annular submitral aneurysm. Contribution of echography apropos of 5 cases].

The authors report 5 cases of annular subvalvular left ventricular idiopathic aneurysm observed within less than 4 years (April 1984 to October 1987) at the hospital of Niamey, Niger. All 5 patients were examined by echocardiography, an exploratory technique which is new for this type of disease. The condition is rare and has been described mostly in black people living in African countries. At the hospital of Niamey, annular subvalvular left ventricular aneurysm was found in 0.04 p. 100 of in-patients and accounted for 0.34 p. 100 of all cardiovascular diseases. The patients were young adults (mean age 20 years), and at the time of diagnosis all were in stage III or IV heart failure. An apical systolic murmur was regularly present; it was due to the mitral regurgitation resulting from the traction exerted by the aneurysm. The prognosis was unfavourable. There were 3 deaths, 2 of which were directly ascribable to the aneurysm and due to thromboembolism (1 case) and arrhythmia (1 case) which are recognized complications of that disease. The diagnosis, always suspected on the finding, on frontal radiographs, of a protruding left cardiac border, was hitherto confirmed by angiography; the authors did not perform angiography and confirmed the diagnosis by echocardiography. Annular subvalvular left ventricular aneurysms are lesions of obscure origin. In our patients, none of the inflammatory, infective or traumatic causes suggested in the literature could be found. Cardiomyopathy associated with the aneurysm was suspected in all patients and confirmed in 3 of them.(ABSTRACT TRUNCATED AT 250 WORDS)