SCCT Expert Consensus Document Provides Measurable Standard for Cardiac CT Angiography

June 6, 2024—The Society of Cardiovascular Computed Tomography (SCCT) announced the publication of a new expert consensus document on standards for quantitative assessments by coronary computed tomography angiography (CCTA).

According to SCCT, the consensus document reviews previously published qualitative and semiquantitative measurements—including clinical guidelines like CAD-RADS 2.0 and disease classification scores such as the CT SYNTAX score for coronary revascularization—to create a comprehensive synopsis concerning quantitative CCTA methods. It offers a framework for terminology, methodology, and reporting of quantitative CCTA analyses to create a common language for both clinicians and researchers.

The expert consensus document by Koen Nieman, MD, et al is available online in JCCT, the Journal of Cardiovascular Computed Tomography. Dr. Nieman, who is past President of SCCT, and Hector Garcia-Garcia, MD, served as co-chairs of the writing group.

“This document provides for the first time a standardization on nomenclature for quantitative parameters derived from CCTA,” commented Dr. Garcia-Garcia in the SCCT press release. “It marks a turning point in reporting of CCTA as it focuses on actual quantification of atherosclerosis.”

As noted in the SCCT press release, the writing group stated that well-described semiquantitative scores and classifications are primarily based on visual interpretation or through categories of obstructive severity rather than exact percentage stenosis measurements. These include Agatston scores, Segment Involvement Score, and assessment of stenosis and plaque within CAD-RADS—the Coronary Artery Disease Reporting and Data System—as well as disease classification scores like CT SYNTAX for coronary revascularization and CT-RECTOR Score for chronic total occlusions.

Despite these available measurements and guidelines, the field currently lacks standards for the quantitative image interpretation of and reporting of CCTA results, advised the writing group; the document was created to fill that gap and create a common language for clinicians and researchers to communicate findings for coronary analyses.

According to SCCT, the writing group stated, “CCTA has been recognized as a promising noninvasive tool to monitor coronary artery disease progression and assess the effects of medical therapy or mechanical interventions in clinical trials. Specific and clear definitions as well as standardization of methodology are essential for CCTA to mature as an accurate and reproducible endpoint in clinical research.”

Additional parameters covered within the document include image acquisition, quality and analysis; artifacts and image degradation; vessel and lumen segmentation; deep learning-based vessel segmentation; serial imaging studies; selection of CCTA-derived study endpoints; and future directions, noted the SCCT press release.