What does quantitative coronary angiography (QCA) measure?

What does quantitative coronary angiography (QCA) measure?

• A. Reference vessel diameter, lesion length, and percent diameter stenosis using image analysis software.
• B. Blood flow velocity across a stenosis.
• C. Mean arterial pressure and central venous pressure.
• D. Left ventricular end-diastolic pressure.

Answer: (C)

Quantitative coronary angiography quantifies the size of the coronary lumen and the degree of narrowing by analyzing digitized angiographic images with specialized software. It determines the reference vessel diameter (the normal segment used for comparison), the minimal lumen diameter at the lesion, and the percent diameter stenosis. It can also measure lesion length by tracing the span of narrowing along the vessel. These measurements are geometric and based on lumen size, not on blood flow or pressures. So the best description is that QCA uses image analysis to measure reference vessel diameter, lesion length, and percent diameter stenosis. It does not assess flow velocity across a lesion or intravascular pressures such as mean arterial pressure, central venous pressure, or left ventricular end-diastolic pressure.

Quantitative coronary angiography quantifies the size of the coronary lumen and the degree of narrowing by analyzing digitized angiographic images with specialized software. It determines the reference vessel diameter (the normal segment used for comparison), the minimal lumen diameter at the lesion, and the percent diameter stenosis. It can also measure lesion length by tracing the span of narrowing along the vessel. These measurements are geometric and based on lumen size, not on blood flow or pressures.

So the best description is that QCA uses image analysis to measure reference vessel diameter, lesion length, and percent diameter stenosis. It does not assess flow velocity across a lesion or intravascular pressures such as mean arterial pressure, central venous pressure, or left ventricular end-diastolic pressure.