Changes

The three possible areas for aortic stenosis to occur are '''subvalvular or subaortic''' (occurs below the valve), '''valvular or aortic''' (occurs at the valve) and '''supravalvular''' (occurs after the valve).  

The three possible areas for aortic stenosis to occur are '''subvalvular or subaortic''' (occurs below the valve), '''valvular or aortic''' (occurs at the valve) and '''supravalvular''' (occurs after the valve).  

The stenotic area causing the problem is a consequence of fibrous tissue on and around the aortic valve. A narrowing of the aortic outflow tract causes an increase in pressure and this increased pressure leads to ''left ventricular dilation and concentric hypertrophy'' as a means of maintaining sufficient cardiac output. The severity of stenosis determines the extent of hypertrophy. Hypertrophy of the myocardium leads to an increased oxygen demand and decreased diastolic filling and insufficient oxygen to meet the new needs of the hypertrophied left ventricle predisposes the animal to ventricular [[:Category:Arrhythmias|arrhythmias]]. There is also an increased risk of bacterial [[Endocarditis|endocarditis]] in animals affected by this condition.  

The stenotic area causing the problem is a consequence of fibrous tissue on and around the aortic valve. A narrowing of the aortic outflow tract causes an increase in pressure and this increased pressure leads to ''left ventricular dilation and concentric hypertrophy'' as a means of maintaining sufficient cardiac output. The severity of stenosis determines the extent of hypertrophy. Hypertrophy of the myocardium leads to an increased oxygen demand and decreased diastolic filling and insufficient oxygen to meet the new needs of the hypertrophied left ventricle predisposes the animal to ventricular [[:Category:Arrhythmia|arrhythmias]]. There is also an increased risk of bacterial [[Endocarditis|endocarditis]] in animals affected by this condition.

==Signalment==

==Signalment==