Turner's syndrome is maximally associated with:

Turner syndrome is characterized by a constellation of findings that result from paial or complete monosomy of the X chromosome. It is the most common chromosomal abnormality in females, with an incidence of 1 per 2500 to 3000 liveborn girls, which corresponds to approximately 2 million cases worldwide. Turner syndrome is caused by complete or paial absence of an X chromosome. The most common karyotype is monosomy X (45,X). The most common cardiovascular abnormalities are bicuspid aoic valve, which is present in 10% to 20%, and coarctation of aoa, present in 10% of adult cases. Also Know: The most common cardiac abnormalities with downs syndrome are atrioventricular canal defect and isolated VSD, which occur in 45% and 35% of cases, respectively. Ref: Marian A.J., Brugada R., Robes R. (2011). Chapter 82. Cardiovascular Diseases Caused by Genetic Abnormalities. In V. Fuster, R.A. Walsh, R.A. Harrington (Eds), Hurst's The Hea, 13e.