A normal heart gradient, specifically across the aortic valve, is typically very small, usually a few mmHg (millimeters of mercury).
Here's a breakdown:
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Pressure Gradient Explained: A heart gradient refers to the pressure difference across a heart valve. It indicates how much harder the heart has to work to pump blood through that valve.
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Aortic Valve: We're primarily discussing the pressure gradient across the aortic valve, which controls blood flow from the heart's left ventricle into the aorta (the main artery supplying blood to the body).
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Normal Gradient: In a healthy heart with a normally functioning aortic valve, there is little resistance to blood flow. Therefore, the pressure before (in the left ventricle) and after (in the aorta) the valve is very similar, resulting in a gradient of only a few mmHg.
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Elevated Gradient: A significantly higher pressure gradient indicates a problem, most commonly aortic stenosis (narrowing of the aortic valve). In severe stenosis, the gradient can reach 100 mmHg or even higher. This increased gradient is due to:
- Increased Resistance: The narrowed valve opening forces the heart to pump harder to push blood through.
- Turbulence: The narrowed opening creates turbulent blood flow, further increasing the pressure difference.
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Clinical Significance: Measuring the aortic valve gradient via echocardiography (ultrasound of the heart) is a crucial diagnostic tool for assessing the severity of aortic valve disease.
