Heart and Vascular

Plaque Analysis

For a long time, doctors primarily focused on the degree of narrowing in an artery. But we now know that not all plaque is created equal. Plaque analysis, which is done by advanced software on the CCTA images, looks at the composition and volume of the plaque.

This analysis provides crucial information:

• Plaque Types: It differentiates between different types of plaque, such as calcified (hard) and non-calcified (soft) plaque. Soft, non-calcified plaque is often considered more dangerous because it’s more likely to rupture, which can trigger a blood clot and cause a heart attack.
• Total Plaque Burden: It measures the total volume of plaque throughout the coronary arteries, giving a more complete picture of the disease.
• Vulnerable Plaque: It can identify characteristics of “vulnerable” or high-risk plaque, which may not be causing a severe blockage yet but could pose a risk for a future cardiac event.

Plaque analysis shifts the focus from just “Is there a blockage?” to “What’s the overall health of the artery walls, and is there a hidden danger?”

Fractional Flow Reserve (FFR)

Traditionally, Fractional Flow Reserve (FFR) was an invasive procedure done in a catheterization lab. It involves threading a special wire into a coronary artery to measure the blood pressure both before and after a blockage. The ratio of those two pressures tells you how much the blockage is actually restricting blood flow to the heart muscle. An FFR value of 0.80 or lower is typically considered a sign that the blockage is significant and may require intervention, like a stent.

The most transformative development is CCTA-derived Fractional Flow Reserve (FFR-CT). This non-invasive technology employs computational analysis and artificial intelligence (AI) to create a detailed simulation of blood flow based on CCTA data. It accurately quantifies FFR throughout the coronary tree, circumventing the need for an invasive procedure.

Putting It All Together

When used together, CCTA, plaque analysis, and FFR-CT provide a powerful, non-invasive diagnostic solution:

1. A CCTA is performed to get the initial “road map.”
2. Plaque analysis is applied to the CCTA images to evaluate the total plaque burden and identify high-risk features.
3. FFR-CT is then calculated from the same CCTA images to determine the physiological impact of any blockages.

This combined method allows doctors to determine the size and nature of a blockage and assess whether it is severely limiting blood flow to the heart muscle. This helps guide treatment, avoid unnecessary invasive procedures, and create a more personalized risk assessment.