What diagnostic study can show a small aortic orifice during systole in a patient with aortic stenosis?

An echocardiogram is the most effective diagnostic study for assessing aortic stenosis, particularly in visualizing the aortic valve orifice during systole. This non-invasive imaging technique utilizes ultrasound waves to produce dynamic real-time images of the heart's structures and function.

In the case of aortic stenosis, the echocardiogram can clearly demonstrate the narrowing of the aortic valve and quantify the degree of stenosis by measuring the dimensions of the aortic orifice. It can also assess associated features like left ventricular hypertrophy or blood flow velocity across the valve.

While the other options may contribute to the overall evaluation of a patient with aortic stenosis, they do not primarily focus on directly visualizing the aortic orifice. An electrocardiogram (EKG) provides information about electrical activity and can reveal abnormalities related to left ventricular hypertrophy or strain but lacks the anatomical visualization of the valve. X-rays may show signs of heart enlargement or calcifications, but they cannot depict the valve structure or function. Cardiac catheterization can provide pressure gradients and confirm severity, but it is more invasive and typically reserved for cases where there is a need for further intervention, rather than serving as a primary diagnostic tool.

In summary