Annular Subvalvar Left Ventricular Aneurysms

Abstract

The radiological findings in 46 Nigerian patients with an unusual form of aneurysm termed annular subvalvar left ventricular aneurysms are reviewed. The anatomy of these left ventricular aneurysms is described with particular emphasis on their mode of intracardiac dissection. The most frequent type has an opening beneath the mitral valve and mitral incompetence is present. The majority of patients showed an abnormal contour of the left border of the heart or calcification of an aneurysmal loculus in a chest radiograph, but a group of patients is described in whom the aneurysm was intracardiac and caused no significant deformity to the cardiac contour apart from cardiomegaly. Difficulties of diagnosis are discussed. The value of left ventricular angiocardiography in confirming the diagnosis is illustrated and the differential diagnosis is discussed. Available evidence suggests that a genetic anatomical factor rather than any acquired cause may be the explanation for the development of this form of cardiac aneurysm, but the evidence is not yet conclusive.