Marfan Syndrome in Sport

The features that bring a person to an MSK or SEM clinic are skeletal and often striking. Affected people tend to be tall with disproportionately long limbs, so the arm span exceeds the height, and long, slender fingers and toes. Two quick bedside signs help: wrapping a hand around the opposite wrist so the thumb and little finger overlap (the wrist sign), and folding the thumb across the palm under closed fingers so its tip projects beyond the hand (the thumb sign).

Other recurrent features include a sunken or projecting chest wall, spinal curvature, flat feet, reduced elbow straightening, joint hypermobility, a high arched palate with crowded teeth, stretch marks, and dural ectasia, a stretching of the spinal cord covering that can cause low back or leg symptoms. The eyes are commonly affected, most characteristically by lens dislocation, with short-sightedness and a higher risk of retinal detachment.

Being tall or hypermobile alone is not enough, and many such athletes have none of the dangerous pathology. Suspicion rises when several features cluster together, particularly with lens dislocation, aortic root widening, a relevant family history or a known fibrillin-1 change.

Most people with Marfan syndrome feel well, and it is often picked up from the physical features rather than from symptoms. When symptoms do occur they may reflect the complications: breathlessness or a murmur from valve leakage, visual disturbance, or back pain from spinal changes.

The presentation that must never be missed is acute aortic dissection, classically sudden, severe, tearing chest or back pain that can occur during or after exertion, and a sudden collapse in a tall young athlete may be its first sign. Because so much of the condition is silent, feeling well and a normal examination on the day do not exclude significant aortic disease.

Echocardiography is the first-line test, measuring the aortic root at the sinuses and screening the valves. In children and adolescents aortic size is reported as a Z-score, an age and body-size adjusted measure, since a size that is normal for a large adult may be abnormal for a child, and a root Z-score of 2 or above is one of the cardinal findings. In adults the absolute diameter and growth rate guide decisions.

For surveillance of the rest of the aorta, magnetic resonance angiography is preferred where feasible, especially in young people, with computed tomography angiography reserved for when magnetic resonance imaging is unsuitable or an acute event is suspected. Ophthalmology assesses for lens dislocation, and genetic testing can identify a fibrillin-1 change.

Diagnosis follows the revised Ghent criteria, which combine aortic root dilatation or dissection, lens dislocation, a fibrillin-1 mutation, family history and a systemic features score, with a family history lowering the threshold needed. Dangerous mimics that must be excluded include homocystinuria, Loeys-Dietz syndrome and vascular Ehlers-Danlos syndrome, where aortic risk and surgical thresholds may differ.

Care is led by a specialist team spanning cardiology, genetics and ophthalmology, and the SEM clinician's role is to recognise, refer and advise. Medical treatment reduces aortic wall stress and slows widening, usually with a beta-blocker or an angiotensin receptor blocker such as losartan, with combination treatment reserved for rapid progression or larger dimensions.

The aorta is kept under lifelong imaging surveillance, and when the root reaches a specialist-defined size, planned root replacement is offered before a dissection can occur. For reference, this is commonly considered around 50 millimetres, or nearer 45 millimetres with rapid growth, a family history of dissection at smaller sizes or significant valve leak; the SEM doctor does not set the threshold but should recognise when an athlete is clearly unsafe to clear.

Sport advice is where the SEM clinician contributes most. The concern is any effort that sharply raises blood pressure and aortic wall stress, so heavy resistance, one-repetition-maximum lifts, lifting to failure, breath-holding strain and maximal intervals are avoided, along with contact and collision sports, which add a risk of direct aortic and eye injury.

Recommended activity is low static and low-to-moderate dynamic, set against aortic size and the wider picture, and specialist assessment may include an exercise test with blood pressure response before clearing anything beyond gentle activity. A tall athlete with the phenotype should not be cleared for high-intensity, static-heavy or contact sport while assessment is pending, and root surgery does not grant automatic clearance, as the remaining native aorta stays at risk.

On the musculoskeletal side, avoid treating the joint or back complaint in isolation: favour controlled strengthening, proprioception and pacing over aggressive end-range stretching, and consider orthotics for symptomatic flat feet.

• •The revised Ghent criteria provide the international framework for diagnosing Marfan syndrome and guide which features and tests confirm it.
• •European Society of Cardiology guidance on aortic disease and on sports cardiology informs aortic surveillance, medical therapy, exercise testing and activity advice.
• •National Health Service inherited cardiac and aortopathy services, clinical genetics and the national Genomic Medicine Service support fibrillin-1 testing, wider aortopathy gene panels when indicated, and cascade screening of relatives.
• •Patient organisations including the Marfan Trust, Cardiac Risk in the Young (CRY) and Aortic Dissection Awareness UK and Ireland provide information and support.

• •Marfan syndrome is an autosomal dominant connective tissue disorder of fibrillin-1, and the life-threatening sports risk is aortic root widening leading to dissection.
• •The SEM or musculoskeletal clinician is well placed to spot the phenotype: tall stature, long limbs, arachnodactyly, chest wall deformity, scoliosis, hypermobility and lens dislocation.
• •Diagnosis uses the revised Ghent criteria, where a root Z-score of 2 or above, lens dislocation, a fibrillin-1 mutation, family history and a systemic score all feed in.
• •Echocardiography measures the aortic root at the sinuses, magnetic resonance angiography is preferred for surveillance, and ophthalmology assesses for lens dislocation.
• •Management is specialist-led: a beta-blocker or angiotensin receptor blocker, lifelong surveillance, and prophylactic root surgery around 50 millimetres, lower with risk factors.
• •Avoid heavy static loading, maximal exertion and contact sport; permitted activity is low static, low-to-moderate dynamic, individualised and specialist-guided.