12th April 2024

Marfan syndrome

A genetic connective tissue disorder affecting the production of fibrillin. It follows an autosomal dominant pattern, affecting FBN1 gene on chromosome 15. Typical presentation includes excess long bone growth causing dolichostenomelia (disproportionate extremity to trunk length), joint laxity (pectus carinatum/excavatum, pes planus, acetabular protrusion/hip dislocations), arachnodactyly and ectopia lentis (upwards dislocated lens). Due to abnormal elastic fibre formation, patients are at increased risk of several cardiac pathologies, such as aortic regurgitation, mitral valve prolapse and dilatation/dissection of vessels. Management involves investigating and monitoring for cardiac pathologies with echocardiography, CT and MRI. Beta-blockers are used to reduce myocardial contractility and pulse pressure and lower the risk of aortic dilatation. Elective repair or replacement is also considered.