Invasive coronary angiography findings across the CAD-RADS classification spectrum.

Area of Science:

• Cardiology
• Radiology
• Medical Imaging

Background:

• The Coronary Artery Disease Reporting and Data System (CAD-RADS) is a recent classification system for coronary artery disease (CAD) evaluated by computed tomography.
• CAD-RADS primarily assesses stenosis severity but may not fully represent the intricate spatial distribution, burden, and complexity of CAD lesions.
• Understanding the limitations of CAD-RADS is crucial for accurate patient stratification and treatment planning in cardiovascular medicine.

Purpose of the Study:

• To investigate the relationship between the CAD-RADS classification and the spatial distribution, burden, and complexity of coronary artery lesions.
• To compare CAD-RADS findings with detailed anatomical information obtained from invasive coronary angiography (ICA).
• To evaluate whether CAD-RADS adequately reflects the heterogeneity of coronary anatomy in patients with significant coronary artery disease.

Main Methods:

• A study population of stable patients who underwent both coronary computed tomography angiography (CCTA) and ICA was retrospectively analyzed.
• Patients were categorized using the established CAD-RADS criteria (0 to 5).
• Invasive coronary angiography findings were used to calculate the SYNTAX score and the CAD extension index, assessing lesion complexity and extent.

Main Results:

• Significant correlations were found between CAD-RADS categories and both the SYNTAX score (p < 0.0001) and the CAD extension index (p < 0.0001).
• However, substantial variability in coronary anatomy complexity was observed among patients within the same CAD-RADS categories, particularly for CAD-RADS ≥ 4A.
• In patients with CAD-RADS 5 (total occlusion), a significant proportion (30%) involved distal segments or secondary branches, and 30% had concomitant non-extensive severe disease.

Conclusions:

• While CAD-RADS correlates with lesion severity and complexity, it may not fully encompass the spatial distribution and intricate anatomical variations of coronary artery disease.
• The study highlights the heterogeneity within CAD-RADS classifications, suggesting that additional imaging or clinical parameters might be needed for comprehensive risk assessment.
• Invasive coronary angiography provides a more detailed assessment of coronary anatomy complexity, which can differ significantly even within similar CAD-RADS categories.