The prevalence of aortic valve disease is not well defined, and it is not known to what degree gender and age affect testing and surgery for this condition. The study aim was to describe the prevalence of aortic valve disease in the United States population by extrapolating from administrative claims databases; and to investigate differences associated with gender and age in referral, diagnostic testing, and aortic valve replacement (AVR). A claims database of approximately five million privately insured beneficiaries and a 5% sample of Medicare beneficiaries were queried for patients with aortic valve disease. Prevalence was calculated by age group and gender, and extrapolated to the 2005 US population. The proportion of patients with a cardiologist or cardiovascular surgeon visit, performance of echocardiography or stress testing, and AVR within a year of diagnosis was determined. The extrapolated prevalence of aortic valve disease in the US in 2005 was 1.8% (approximately 5.2 million people); in persons aged > or =65 years, prevalence was 10.7%. Women were seen by a specialist, underwent diagnostic tests and underwent AVR at rates significantly lower than men, as did patients aged > or =80 years compared to those aged 65-79 years. AVR was performed at approximately half the rate in women (1.4%) compared to men (2.7%, p or =80 years (1.1%) compared to those aged 65-79 years (2.5%, p <0.001). In 2005, approximately 5.2 million adults in the US were estimated to have a diagnosis of aortic valve disease. Advanced age and female gender were associated with lower rates of specialist visits, diagnostic testing, and AVR.