ANOCA: An Under-Recognised and Undertreated Disorder. Insights From the CADOSA Registry

While the management of stable coronary artery disease (CAD) patients is largely established, patients with angina and non-obstructive coronary artery (ANOCA) pose a clinical challenge. This study compared chest pain characteristics and management of ANOCA vs stable CAD patients. All consecutive ANOCA (stenosis <50%) and stable CAD enrolled in the CADOSA (Coronary Angiogram Database of South Australia) Registry between 2012 and 2018 were included, identifying 2,327 ANOCA and 4,248 stable CAD patients among 30,015 angiograms performed. Characteristics were compared using t-test and chi-squared analysis. ANOCA patients were younger (61±11 vs 66±11, p<0.005) and more often female (58% vs 27%, p<0.005) in comparison to stable CAD. ANOCA and stable CAD patients were indistinguishable in relation to (i) chest pain quality (tightness, 43% vs 41%, p>0.005), (ii) precipitant (exertion, 60% vs 65%, p<0.005), (iii) relieving factors (rest, 56% vs 54%, p>0.005, and nitrates 20% vs 22%, p>0.005), and (iv) frequency of undertaking a non-invasive ischaemia test (61% vs 58%, p<0.005) and objective evidence of ischaemia (70% vs 76%, p>0.005). In contrast, the discharge management between patients with ANOCA and stable CAD was markedly different in (i) cardioprotective agents (81% vs 96%, p<0.005), and (ii) anti-ischaemic agents (75% vs 90%, p<0.005). Despite patients with ANOCA having indistinguishable pre-angiography clinical characteristics and presentation to those with stable CAD, following angiographic documentation of non-obstructive coronary arteries, they usually are not provided with a satisfactory diagnosis for their symptoms, nor prescribed cardioprotective/anti-ischaemic agents.