The medical term for aorta stenosis is aortic valve stenosis, referring to a narrowing of the aortic valve, according to WebMD. Stenosis impedes the valve's ability to open fully, requiring the heart to work harder to pump blood through the valve.
The increased effort placed on the heart to pump blood through an aortic valve impeded by stenosis causes heightened pressure within the left ventricle of the heart and leads to the heart wall becoming thicker, explains WebMD. Over time, this overcompensation and pressure buildup can lead to heart failure.
Among patients ages 65 and older, the most common cause of aortic stenosis is a condition called senile calcific aortic stenosis, reports MedicineNet.com. Heart valves are formed by leaflets of flesh called cusps. Over time, the protein collagen of these leaflets is broken down and calcium deposits accumulate on the cusps, reducing their mobility as they open and close. Turbulence in the bloodstream through the valves causes scarring, thickening and eventually stenosis, as it flows across the leaflets whose mobility has been reduced by calcification.
In cases of mild and moderate aortic stenosis, the heart can make up for the restricted blood flow through the valve by working harder, so these cases may not present symptoms, reports WebMD. Symptoms that do appear usually involve chest pain or tightness, dizziness and shortness of breath. Treatment for aortic stenosis usually requires surgery to repair or replace the valve.