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Updated 2017 European and American guidelines for prosthesis type and implantation mode in severe aortic stenosis

Both the European Society of Cardiology (ESC) and American Heart Association/American College of Cardiology (AHA/ACC) guidelines for management of adults with valvular heart disease have been updated this year in response to publication of new evidence justifying revised or new recommendations.1 2 In particular, more detailed guidance is provided for choice of valve prosthesis type and implantation mode in patients with severe valvular aortic stenosis (AS).

There are three distinct steps in decision making in adults with severe AS:



Both guidelines acknowledge the complexity of AS assessment, emphasising that the current definition of severe AS includes:



In patients with severe AS and a high velocity/gradient, valve area usually is 1.0 cm2 or less, but this is not required for diagnosis in either guideline as long as a reversible high flow state has been excluded. Low-flow in this context is defined as a stroke volume index 35 mL/m2 or less. When LV EF is low (<0.50), severe AS is defined as an aortic velocity ≥4 m/s, without an increase …