CORONARY microvascular dysfunction and myocardial endotypes of ischaemia with no obstructive coronary arteries (INOCA) are significantly associated with cumulative atherosclerotic plaque burden, as measured by Gensini scores.
The study explored the relationship between atherosclerosis and INOCA endotypes, using data from the CorMicA trial. It investigated whether cumulative atherosclerotic plaque burden, assessed via the Gensini score, correlates with novel invasive indices of coronary microvascular function, including microvascular resistance reserve (MRR) and resistive reserve ratio (RRR). Additionally, it examined the distribution of plaque burden across INOCA endotypes, such as microvascular angina (MVA), vasospastic angina (VSA), and mixed or non-cardiac symptoms.
The analysis included 151 participants (median age 61 years, 73.5% female) who underwent simultaneous coronary angiography and invasive coronary function tests. Luminal stenosis and plaque burden were assessed blind to coronary physiology outcomes. The median Gensini score was 6.0 (IQR 2.5–11.0). Significant univariate associations were observed between raised Gensini scores and coronary flow reserve (CFR, p=0.012), MRR (p=0.026), and RRR (p=0.026), but not with IMR (p=0.445). Multivariable models confirmed these relationships, independent of potential confounders. Gensini scores varied significantly across INOCA endotypes, with the highest scores in participants with mixed MVA/VSA (median 9.0) and the lowest in those with non-cardiac symptoms (median 3.5, p=0.030).
These findings establish a mechanistic link between coronary microvascular dysfunction and cumulative plaque burden, suggesting that atherosclerosis plays a key role in INOCA-related cardiovascular events. Clinically, this underscores the importance of therapies targeting atherosclerosis in patients with MVA. Future research should assess whether antiatherosclerosis interventions can mitigate cardiovascular risks in this population and further clarify the role of microvascular dysfunction in INOCA pathophysiology.
Reference
Ang DT et al. Coronary microvascular function and atherosclerotic plaque burden in ischaemia and no obstructive coronary arteries: a secondary analysis of the CorMicA trialHeart. 2024;DOI:10.1136/heartjnl-2024-324677.
