Why does aortic stenosis increase the risk of heart failure when the left ventricle's ejection fraction remains initially normal?

💡 Explanation

Aortic stenosis increases afterload because the left ventricle must generate more pressure to overcome the narrowed valve. This leads to compensatory hypertrophy to maintain cardiac output; therefore, elevated afterload and hypertrophy increase heart failure risk rather than improved oxygen supply, relaxation, or preload adaptation.

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