Protocol and rationale of the Australian multicentre registry for serial cardiac computed tomography angiography (ARISTOCRAT): a prospective observational study of the natural history of pericoronary adipose tissue attenuation and radiomics

Kevin Cheng; Andrew Lin; Peter J Psaltis; Adil Rajwani; Angus Baumann; Nicholas Brett; Nadarajah Kangaharan; James Otton; Stephen J Nicholls; Damini Dey; Dennis T L Wong

doi:10.21037/cdt-23-392

Protocol and rationale of the Australian multicentre registry for serial cardiac computed tomography angiography (ARISTOCRAT): a prospective observational study of the natural history of pericoronary adipose tissue attenuation and radiomics

Cardiovasc Diagn Ther. 2024 Jun 30;14(3):447-458. doi: 10.21037/cdt-23-392. Epub 2024 Jun 27.

Authors

Kevin Cheng¹, Andrew Lin^{1

2}, Peter J Psaltis^{3

4

5}, Adil Rajwani⁶, Angus Baumann⁷, Nicholas Brett⁸, Nadarajah Kangaharan⁹, James Otton¹⁰, Stephen J Nicholls¹, Damini Dey², Dennis T L Wong¹

Affiliations

¹ Monash Cardiovascular Research Centre, Victorian Heart Institute, Monash Health, Monash University, Clayton, VIC, Australia.
² Cedars-Sinai Medical Center, Biomedical Imaging Research Institute, Los Angeles, CA, USA.
³ Vascular Research Centre, Heart and Vascular Program, Lifelong Health Theme, SAHMRI, Adelaide, SA, Australia.
⁴ Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia.
⁵ Department of Cardiology, Royal Adelaide Hospital, Central Adelaide Local Health Network, Adelaide, SA, Australia.
⁶ Department of Cardiology, Royal Perth Hospital, Perth, WA, Australia.
⁷ Alice Springs Hospital, Alice Springs, NT, Australia.
⁸ Department of Radiology, Royal Hobart Hospital, Hobart, TAS, Australia.
⁹ Department of Cardiology, Royal Darwin Hospital, Tiwi, NT, Australia.
¹⁰ Department of Cardiology, Liverpool Hospital, Liverpool, NSW, Australia.

Abstract

Background: Vascular inflammation plays a crucial role in the development of atherosclerosis and atherosclerotic plaque rupture resulting in acute coronary syndrome (ACS). Pericoronary adipose tissue (PCAT) attenuation quantified from routine coronary computed tomography angiography (CCTA) has emerged as a promising non-invasive imaging biomarker of coronary inflammation. However, a detailed understanding of the natural history of PCAT attenuation is required before it can be used as a surrogate endpoint in trials of novel therapies targeting coronary inflammation. This article aims to explore the natural history of PCAT attenuation and its association with changes in plaque characteristics.

Methods: The Australian natuRal hISTOry of periCoronary adipose tissue attenuation, RAdiomics and plaque by computed Tomographic angiography (ARISTOCRAT) registry is a multi-centre observational registry enrolling patients undergoing clinically indicated serial CCTA in 9 centres across Australia. CCTA scan parameters will be matched across serial scans. Quantitative analysis of plaque and PCAT will be performed using semiautomated software.

Discussion: The primary endpoint is to explore temporal changes in patient-level and lesion-level PCAT attenuation by CCTA and their associations with changes in plaque characteristics. Secondary endpoints include evaluating: (I) impact of statin therapy on PCAT attenuation and plaque characteristics; and (II) changes in PCAT attenuation and plaque characteristics in specific subgroups according to sex and risk factors. ARISTOCRAT will further our understanding of the natural history of PCAT attenuation and its association with changes in plaque characteristics.

Trial registration: This study has been prospectively registered with the Australia and New Zealand Clinical Trials Registry (ACTRN12621001018808).

Keywords: Cardiac computed tomography angiography; atherosclerosis; inflammation; pericoronary adipose tissue (PCAT); radiomics.