Cardiovascular manifestations of mucopolysaccharidosis type VI (Maroteaux-Lamy syndrome)

The aim of the article is to gather and summarize the published data about the incidence, course of illness, treatment possibilities and complications of cardiovascular disorders in patients with mucopolysaccharidosis type VI (MPS VI) also known as Maroteaux-Lamy syndrome. MPS VI is a lysosomal storage disorder caused by deficient activity of N-acetylogalactosamine-4-sulfatase leading to progressive intracellular accumulation of glycosaminoglycans. The relatively low birth prevalence ranging from 1 in 43,000 to 1 in 1.5 million births mirrors the limited descriptions of the cardiovascular disorders in the medical literature. Patients with MPS VI can be specifically treated with enzyme replacement therapy. Extra-cardiac features include growth retardation, coarse facial features, stiff joints, skeletal malformations (dysostosis multiplex), respiratory problems, corneal clouding, and hepatosplenomegaly. The clinical presentation varies considerably, however the development of heart disease and cardiac dysfunction is a serious problem in the majority of patients. The most characteristic cardiac presentation is valvular disease, while other MPS VI patients also develop cardiomyopathy, fibroelastosis, pulmonary hypertension, cardiac conduction system disorders and other complications. There are also reports on acute heart failure. Early cardiovascular manifestation may escape detection since joint stiffness or skeletal malformations limit maximal exercise levels and respiratory system involvement may mask the underlining cardiac insufficiency. A correct and timely diagnosis offers the possibility of disease-specific treatment leading to sustained clinical benefits for cardiac and non-cardiac MPS VI manifestations.