<prompt> Answer this question truthfullyCould you explain what is low flow, low gradient aortic stenosis?  <response>: <reason> Low flow low gradient aortic stenosis with low ejection fraction is reported in approximately 5 to 10 of patients with severe aortic stenosis; whereas low flow low gradient aortic stenosis with normal left ventricular ejection fraction is observed in 10 to 25 of patients with severe aortic stenosis. 