Nkomo V, Gardin J, Skelton T, Gottdiener J, et al. Burden of Valvular Heart Diseases: A population-based study. Lancet. September 2006; 368(9540). http://www.ncbi.nlm.nih.gov/pubmed/16980116
Between the ages of 18 and 44, less than 1% of the U.S. population has heart valve disease. This increases to 8.5% between ages 65 and 74, and 13.2% after age 75.