 Also, abnormalities in other mesenchymal tissues (bone matrix and lymphatic vessels) suggests a similar primary mesenchymal defect in patients with Turner syndrome.However, no evidence suggests that patients with Turner syndrome have a significantly higher risk of aortic dilatation and dissection in absence of predisposing factors.So, the risk of aortic dissection in Turner syndrome appears to be a consequence of structural cardiovascular malformations and hemodynamic risk factors rather than a reflection of an inherent abnormality in connective tissue.