LYMPHATIC ANEURYSM OF THE HEART

Abstract

The Annular Subvalvular Left Ventricular Aneurysm (ASLVA) is a rare entity, which occursusually in young ethnic groups from Sub-Saharan Africa and South India. These aneurysms aresituated immediately beneath the mitral and aortic valves and extend around in the substance offibrous ring, from which valves arise. Their etiology is still obscure.Fifteen consecutive cases of ASLVA were treated surgically for this heart condition. Theirclinical presentations, surgery, histopathology of aneurysmal wall were studied.Infective diseases with associated mediastinal lymphadenopathy were observed in allpatients prior to the time the diagnosis of ASLVA was made. Nine patients had alsolymphadenopathy in another region. Sinus of Valsalva Aneurysm was an associated finding inthree patients. Dense fibrous tissue was the most common histopathological feature of theaneurysmal wall. Endothelium within the structure of the aneurysmal wall, “compressed”myocardium around the ASLVA wall, dilated and deformed heart lymphatics with lymphextravasation, and lymphatic neovascularization were all found in some histopathologyspecimens.Post-inflammatory destruction of mediastinal lymph nodes may obstruct lymph outflow fromthe heart, cause backwards lymphostasis, damage lymphatic vessels in the heart, and can lead toaneurysm formation. Increased intravascular shear stress triggers release of endothelial growthfactors (bFGF, TGF-beta) and leads to neovascularization and tissue fibrosis, the most commonfeature of aneurysmal wall.