National Heart Foundation of Australia: position statement on coronary artery calcium scoring for the primary prevention of cardiovascular disease in Australia

Abstract

ardiovascular disease (CVD) is a leading cause of death in Australia 1 and contributes to a significant health care burden. 2 Australian guidelines for management of CVD risk in primary prevention recommend the assessment of absolute CVD risk, using the algorithm developed by the National Vascular Disease Prevention Alliance (NVDPA), which calculates an individual's risk of a CVD event over a 5-year period. 3 Additional risk modifiers, such as coronary artery calcium (CAC) scoring, have been investigated as a way to improve the predictive performance of established risk assessment algorithms. [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23] CAC scoring measures the amount of calcium in the coronary arteries from a computed tomography (CT) scan of the heart. A positive CAC score, measured in Agatston units (AU), is a marker of atherosclerosis, with increasing CAC scores correlating to increasing risk of CVD events and a CAC score of 0 AU indicating an absence of CAC and a low risk of CVD events. 24,25 Evidence for the ability of CAC scoring to improve the predictive performance of traditional risk assessment models, and for the ability of CAC-guided management to reduce CVD morbidity and mortality, is evolving.This position statement provides practical advice to health professionals regarding the use of CAC scoring to assist in defining risk in the primary prevention of CVD in Australia. It is not intended to be an update to Australian absolute CVD risk guidelines, nor is it our purpose to compare CAC scoring and absolute CVD risk equations as standalone predictors of risk. Rather, this article outlines a position specifically on the use of CAC scoring in the context of, and ancillary to, standard methods of risk assessment. The National Heart Foundation of Australia acknowledges that the limited availability of Australian published literature affects the certainty of the evidence for the role of CAC scoring in the Australian setting. However, we recognise the need for practical guidance for the use of CAC scoring, and thus these conditional recommendations with expert consensus are based on the Australian and international evidence available at the time. This position statement builds upon a previous consensus statement from the Cardiac Society of Australia and New Zealand.

Effect of C1q/TNF-Related Protein 9 on Coronary Artery Calcification: An Observational Study

“…The CAC score was measured using Agatston (standard Agatston CAC score). Studies have shown that CAC scores are independently associated with ASCVD events [ 36 ]. Nixdorf et al showed that patients with CAC scores > 400 are expected to have a 10-year incidence of ASCVD events of 13.50% [ 37 ].…”

Evaluation of an artificial intelligence coronary artery calcium scoring model from computed tomography

“…Although the CAC score is a continuous variable, guidelines recommend a CAC score of ≥ 100 Agatston units as a threshold for initiating statins [4][5][6]. The automated model accurately identified a CAC score >100 Agatston units in 95% of individuals compared with manual human assessment.…”

“…Re-direction of the human operator's role to other tasks instead can further reduce costs associated with CAC scoring, thus making it more widely available. This is important as demand for CAC scoring is likely to increase substantially in the future due to guidelines now recommending its use as an additional non-invasive tool for cardiovascular risk-stratification [4][5][6]. Furthermore, automated models can be applied to large populations for screening or research purposes due to their ability to quantify CAC in seconds and because AI can potentially overcome measurement errors by human observers due to high repeatability [21,23].…”

“…CAC is traditionally assessed noninvasively using electrocardiogram-gated computed tomography (CT) imaging of the heart, without the need for intravenous contrast [3]. Uptake in clinical practice is likely to increase, as guidelines now recommend CAC scoring for reclassifying cardiovascular risk in intermediate or borderline risk individuals, which thereby assists in decisionmaking around preventive therapies [4][5][6].…”

The cost‐effectiveness of coronary calcium score‐guided statin therapy initiation for Australians with family histories of premature coronary artery disease

“…Recent position statements by the Cardiac Society of Australia and New Zealand (CSANZ) 7 and the National Heart Foundation (NHF) 8 reflect CAC recommendations in overseas guidelines, but note that local information on outcomes and cost‐effectiveness is limited. A United States study found that statin treatment guided by CAC scores may be more cost‐effective than standard predicted risk thresholds, and that adherence to therapy is an important contributor to its benefit 9 …”