Understanding Low Flow, Low Gradient Aortic Stenosis

Low-flow, low-gradient aortic stenosis refers to a condition where the aortic gradient is less than 40 mmHg, and the valve area measures under one square centimeter. This condition can be classified into two types: classical low-flow, low-gradient aortic stenosis with reduced ejection fraction, and paradoxical low-flow, low-gradient aortic stenosis with preserved ejection fraction. Common causes of the paradoxical form include atrial fibrillation and pulmonary hypertension, which can lead to reduced stroke volume despite preserved ejection fraction. Recognizing and understanding this distinction is critical for effective diagnosis and treatment in patients presenting with heart failure.