ABSTRACT
BACKGROUND: To investigate the incremental prognostic value of low-attenuation plaque volume (LAPV) from coronary CT angiography datasets. METHODS: Quantification of LAPV was performed using dedicated software equipped with an adaptive plaque tissue algorithm in 1577 patients with suspected CAD. A combination of death and acute coronary syndrome was defined as primary endpoint. To assess the incremental prognostic value of LAPV, parameters were added to a baseline model including clinical risk and obstructive coronary artery disease (CAD), a baseline model including clinical risk and calcium scoring (CACS) and a baseline model including clinical risk and segment involvement score (SIS). RESULTS: Patients were followed for 5.5 years either by telephone contact, mail or clinical visits. The primary endpoint occurred in 30 patients. Quantified LAPV provided incremental prognostic information beyond clinical risk and obstructive CAD (c-index 0.701 vs. 0.767, pâ¯<â¯.001), clinical risk and CACS (c-index 0.722 vs. 0.771, pâ¯<â¯.01) and clinical risk and SIS (c-index 0.735 vs. 0.771, pâ¯<â¯.01. A combined approach using quantified LAPV and clinical risk significantly improved the stratification of patients into different risk categories compared to clinical risk alone (categorical net reclassification index 0.69 with 95% CI 0.27 and 0.96, pâ¯<â¯.001). The combined approach classified 846 (53.6%) patients as low risk (annual event rate 0.04%), 439 (27.8%) patients as intermediate risk (annual event rate 0.5%) and 292 (18.5%) patients as high risk (annual event rate 0.99%). CONCLUSION: Quantification of LAPV provides incremental prognostic information beyond established CT risk patterns and permits improved stratification of patients into different risk categories.
Subject(s)
Computed Tomography Angiography , Coronary Angiography/methods , Coronary Artery Disease/diagnostic imaging , Coronary Vessels/diagnostic imaging , Plaque, Atherosclerotic , Acute Coronary Syndrome/etiology , Acute Coronary Syndrome/mortality , Aged , Algorithms , Cause of Death , Coronary Artery Disease/complications , Coronary Artery Disease/mortality , Coronary Artery Disease/pathology , Coronary Vessels/pathology , Databases, Factual , Disease Progression , Disease-Free Survival , Female , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Predictive Value of Tests , Proportional Hazards Models , Radiographic Image Interpretation, Computer-Assisted , Retrospective Studies , Risk Assessment , Risk Factors , Severity of Illness Index , Time FactorsABSTRACT
PURPOSE: Investigate the influence of adaptive statistical iterative reconstruction (ASIR) and the model-based IR (Veo) reconstruction algorithm in coronary computed tomography angiography (CCTA) images on quantitative measurements in coronary arteries for plaque volumes and intensities. METHODS: Three patients had three independent dose reduced CCTA performed and reconstructed with 30% ASIR (CTDIvol at 6.7 mGy), 60% ASIR (CTDIvol 4.3 mGy) and Veo (CTDIvol at 1.9 mGy). Coronary plaque analysis was performed for each measured CCTA volumes, plaque burden and intensities. RESULTS: Plaque volume and plaque burden show a decreasing tendency from ASIR to Veo as median volume for ASIR is 314 mm3 and 337 mm3-252 mm3 for Veo and plaque burden is 42% and 44% for ASIR to 39% for Veo. The lumen and vessel volume decrease slightly from 30% ASIR to 60% ASIR with 498 mm3-391 mm3 for lumen volume and vessel volume from 939 mm3 to 830 mm3. The intensities did not change overall between the different reconstructions for either lumen or plaque. CONCLUSION: We found a tendency of decreasing plaque volumes and plaque burden but no change in intensities with the use of low dose Veo CCTA (1.9 mGy) compared to dose reduced ASIR CCTA (6.7 mGy & 4.3 mGy), although more studies are warranted.
Subject(s)
Computed Tomography Angiography/methods , Coronary Angiography/methods , Plaque, Atherosclerotic/diagnostic imaging , Radiographic Image Interpretation, Computer-Assisted/methods , Aged , Algorithms , Contrast Media , Humans , Male , Middle Aged , Prospective StudiesABSTRACT
Though conventional coronary angiography (CCA) has been the standard of reference for diagnosing coronary artery disease in the past decades, computed tomography angiography (CTA) has rapidly emerged, and is nowadays widely used in clinical practice. Here, we introduce a standardized evaluation framework to reliably evaluate and compare the performance of the algorithms devised to detect and quantify the coronary artery stenoses, and to segment the coronary artery lumen in CTA data. The objective of this evaluation framework is to demonstrate the feasibility of dedicated algorithms to: (1) (semi-)automatically detect and quantify stenosis on CTA, in comparison with quantitative coronary angiography (QCA) and CTA consensus reading, and (2) (semi-)automatically segment the coronary lumen on CTA, in comparison with expert's manual annotation. A database consisting of 48 multicenter multivendor cardiac CTA datasets with corresponding reference standards are described and made available. The algorithms from 11 research groups were quantitatively evaluated and compared. The results show that (1) some of the current stenosis detection/quantification algorithms may be used for triage or as a second-reader in clinical practice, and that (2) automatic lumen segmentation is possible with a precision similar to that obtained by experts. The framework is open for new submissions through the website, at http://coronary.bigr.nl/stenoses/.
