Accurate quantification of coronary stenosis on coronary CT angiography (CCTA) is essential for appropriate risk stratification and clinical decision-making, yet several technical and interpretative pitfalls can compromise diagnostic accuracy. This second part of a two-part review examines common factors that lead to overestimation or underestimation of stenosis severity, with attention to how these errors influence CAD-RADS categorization, downstream testing, and patient management. Using case-based examples, we describe key contributors to misinterpretation and present practical strategies to mitigate these pitfalls. By recognizing these nuances and employing a structured, standardized interpretive approach, readers can minimize errors in stenosis assessment and enhance the reliability of CCTA as a noninvasive tool for evaluating coronary artery disease.
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