Can CAC absence identify patients with chest pain who can safely avoid additional downstream testing?

USA: The findings from a new study, published in JACC: Cardiovascular Imaging, support the role of a CAC score of 0 as a gatekeeper for more advanced imaging among patients with either stable or acute chest pain (CP). 

The study found that among more than 92,000 patients presenting with chest pain, CAC absence was associated with a very low prevalence of obstructive CAD, a low annualized risk of major adverse cardiac events, and a low prevalence of nonobstructive CAD. 

There is not much consensus on whether the absence of coronary artery calcium (CAC) can help to identify chest pain patients who can safely avoid additional downstream testing. Considering this, Ali M. Agha, Baylor College of Medicine, Houston, Texas, USA, and colleagues aimed to investigate the use of CAC assessment for ruling out obstructive coronary artery disease (CAD) in patients with stable and acute CP, at low-to-intermediate risk of obstructive CAD undergoing coronary computed tomography angiography (CTA) by conducting a systematic review and meta-analysis. 

For this purpose, the researchers searched the online databases for studies published between 2005 and 2021. It included studies examining the relationship between CAC and obstructive CAD (≥50% coronary luminal narrowing) on coronary CTA among patients with stable and acute CP.