The role of dobutamine stress echocardiography based projected aortic valve area in assessing patients with classical low-flow lowgradient aortic stenosis

Aortic stenosis (AS) is the most common valvular heart disease in the US (1). The prevalence of AS increases with age from 0.2% in those aged 50–59 years to 2.8% in adults older than 75 years and up to 9.8% in octogenarians (2,3). It is estimated that AS is responsible for yearly 85,000 aortic valve replacement and 15,000 deaths in North America (4).