MPS I – Cardiovascular System

Clinical complications related to heart disease occur in some patients with MPS I, particularly during the later stages of the disease. In these patients, evidence of cardiovascular involvement by echocardiography can be demonstrated much earlier than that derived from clinical observations. Storage of glycosaminoglycans (heparan sulfate and dermatan sulfate) within and around the valve leaflets results in their thickening and stiffening, which can lead to progressive mitral and aortic regurgitation. Mitral regurgitation is the most common valvular disease in severely affected MPS I patients.^[1] Hypertrophic cardiomyopathy may be diagnosed by echocardiography. Pulmonary hypertension, which can progress to cor pulmonale, may occur as a consequence of sleep apnea.

References

1. Neufeld, E.F., and Muenzer, J. (2001) The mucopolysaccharidoses. In: The Metabolic and Molecular Bases of Inherited Disease. Scriver, C.R., Beaudet, A.L., Sly, W.S., Valle, D., Childs, B., Kinzler, K.W., and Vogelstein, B. (eds.). 8th edition, Vol. III. McGraw-Hill, Medical Publishing Division, pp. 3421.