ECG manifestations of left ventricular hypertrophy (LVH) are common in aortic stenosis and arise as a result of the stenosis having placed a chronically high-pressure load on the left ventricle (with LVH being the expected response to chronic pressure loads on the left ventricle no matter what the cause).As noted above, the calcification process that occurs in aortic stenosis can progress to extend beyond the aortic valve and into the electrical conduction system of the heart. Evidence of this phenomenon may rarely include ECG patterns characteristic of certain types of heart block such as Left bundle branch block. Heart catheterization
Cardiac chamber catheterization provides a definitive diagnosis, indicating severe stenosis in valve area of <1.0 cm2 (normally about 3 cm2). It can directly measure the pressure on both sides of the aortic valve. The pressure gradient may be used as a decision point for treatment. It is useful in symptomatic people before surgery. The standard for diagnosis of aortic stenosis is non-invasive testing with echocardiography. Cardiac catheterization is reserved for cases in which there is a discrepancy between the clinical picture and non-invasive testing, due to risks inherent to crossing the aortic valve, such as stroke. Echocardiogram
Echocardiogram (heart ultrasound) is the best non-invasive way to evaluate the aortic valve anatomy and function. The aortic valve area can be calculated non-invasively using echocardiographic flow velocities.
Conduction abnormalities requiring permanent pacemaker (PPM) implantation remain a common finding after TAVI due to the close proximity of the atrioventricular conduction system to the aortic root. Balloon valvuloplasty
For infants and children, balloon valvuloplasty, where a balloon is inflated to stretch the valve and allow greater flow, may also be effective. In adults, however, it is generally ineffective, as the valve tends to return to a stenosed state. The surgeon will make a small incision at the top of the persons leg and proceed to insert the balloon into the artery. The balloon is then advanced up to the valve and is inflated to stretch the valve open. Heart failure
Acute decompensated heart failure due to AS may be temporarily managed by an intra-aortic balloon pump while pending surgery. In those with high blood pressure nitroprusside may be carefully used. Phenylephrine may be used in those with very low blood pressure. Prognosis
If untreated, severe symptomatic aortic stenosis carries a poor prognosis, with a 2-year mortality rate of 50-60% and a 3-year survival rate of less than 30%. Prognosis after aortic valve replacement for people  younger than 65 is about five years less than that of the general population; for people older than 65 it is about the same. Epidemiology
Approximately 2% of people over the age of 65, 3% of people over age 75, and 4% percent of people over age 85 have aortic valve stenosis.