[Idiopathic subvalvular aneurysm of the left ventricle. Anatomical, clinical and developmental characteristics. Apropos of 13 cases].

The authors report 13 cases of idiopathic subvalvular left ventricular aneurysm (ISVLVA), observed over a 7-year period in a total of 29,617 patients (0.04%). They describe the clinical features, results of complementary investigations and clinical course of this disease. The diagnosis was based on angiographic and anatomical findings in 4 cases and on echocardiographic findings in 10 cases. This series consisted of 10 females and 3 males with a mean age of 37.3 +/- 2.1 years (range: 9 to 72 years). Clinical signs consisted of palpitations in 2 cases, angina pectoris in 4 cases, heart failure in 9 cases, and systolic murmur of mitral incompetence in 13 cases. Chest x-rays showed vaulting of the left ventricle in 8 cases (61.5%). ECG showed sinus rhythm in 11 cases, atrial fibrillation in 2 cases, ventricular tachycardia in 1 case and junctional tachycardia in 1 case. The erythrocyte sedimentation rate was raised in 10 cases (76.9%). Complementary examinations revealed ISVLVA, which was often very large, calcified (7 cases), thrombosed (6 cases), situated on the posterolateral surface of the left ventricle, in a mitral subvalvular position (13 cases) and responsible for mitral incompetence (13 cases). The coronary arteries were normal in the 5 cases in which they were studied. No aetiology was found. Complications included death (1 case), heart failure (9 cases) and arrhythmias (3 cases). No systemic embolism was observed. Medical treatment (digoxin, furosemide, antiarrhythmics) was considered to be fairly effective, but insufficient to prevent episodes of heart failure and arrhythmias.(ABSTRACT TRUNCATED AT 250 WORDS)