[Idiopathic aneurysm of the left ventricle. Apropos of 4 cases operated on with success].

Over a period of 3 years, 4 cases of idiopathic left ventricular aneurysm, 3 white females and one coloured male aged 34, 53, 29 and 47 years respectively, were observed. All presented with paroxysmal ventricular or supraventricular tachycardia, which, in one case, was severe enough in itself to justify surgery. On angiography, large left ventricular aneurysms bordering the mitral annulus and responsible for moderate mitral regurgitation in two patients were demonstrated. Aneurysmectomy was only possible in 2 cases, the other two having pericardial adhesions with a risk of uncontrollable haemorrhage during dissection being managed by suture of the neck of the aneurysm. The surgical results were very satisfactory, especially with respect to the arrhythmias with a follow-up of 48, 24, 15 and 9 months respectively. In a review of the literature, 93 cases of idiopathic left ventricular aneurysm were analysed, less than 20 of which have been managed surgically. Left ventricular aneurysms seem to be large fibrotic structures located at the border of the mitral, or, less commonly, below the aortic annulus. It is important to differentiate them from congenital left ventricular diverticuli which are usually located at the apex, have muscular walls and are therefore contractile. The aetiology of these aneurysms is unknown: the possible role of myocardial infarction may be excluded as the coronary arteries are always normal on angiography and at autopsy. The relatively young age of the patients is also an argument against this hypothesis. Other suggested causes such as syphilis, tuberculosis, Chagas' disease, non-specific myocarditis, sarcoidosis and thoracic trauma may also be excluded. Surgery seems to be indicated in cases complicated by resistant arrhythmias, peripheral embolism or when the aneurysm increases rapidly in size.