Aortic valve stenosis occurs when calcium deposits in the valve cause leaflets hardening. It is a degenerative process that gets worse as the person ages. As the disease develops, valve opening is narrowed, obstructing blood flow and forcing the heart to pump harder. 

Aortic valve replacement is the standard treatment for severe aortic stenosis. Without treatment, a large ratio of people with severe aortic stenosis who are experiencing symptoms will die in about two years. Transcatheter implantation of the aortic valve, or TAVI, allows replacement of the aortic valve without opening the chest. This less invasive process is available for patients considered at high risk for open heart surgery.  

https://solaci.org/es/pdfs/estenosis_pacientes.pdf
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