<prompt> What percentage of Downs syndrome patients also have congenital cardiovascular disease?0.1032050  <response>: This fact is woh remembering: one-fifth of Downs syndrome patients have congenital cardiovascular disease, most commonly an ostium primum type of ASD andor a ventricular septal defect. This is a sufficiently high incidence to justify at least one echocardiogram in each of these childrens lives. Affected children are also paicularly vulnerable to seizures, and as adults may develop an Alzheimer-like dementia in their mid 40s. Ref: Wyatt C., Kemp W.L., Moos P.J., Burns D.K., Brown T.G. 2008. Chapter 6. Genetic Disorders. In C. Wyatt, W.L. Kemp, P.J. Moos, D.K. Burns, T.G. Brown Eds, Pathology: The Big Picture. 