The triglyceride-glucose index is an indicator of high-risk coronary microvascular dysfunction in patients with angina and non-obstructive coronary artery disease

Abstract The triglyceride glucose (TyG) index, a metric used to evaluate insulin resistance, has received limited attention in its association with coronary microvascular dysfunction (CMD). Our study aims to explore the predictive potential of the TyG index for high-risk CMD due to exhibited angina and non-obstructive coronary artery disease (ANOCA), which is classified by a novel coronary angiography-derived index of microcirculatory resistance (caIMR), a safe and accessible diagnostic approach for risk assessment. The patients aged 45 years and older undergoing invasive coronary angiography between August 2024 and October 2025 in a single-center were retrospectively analyzed and classified as high-risk CMD (caIMR40 units, n = 136) or low-risk CMD (caIMR≤40 units, n=112) based on caIMR risk thresholds. The TyG index and caIMR were prospectively evaluated. The cutoff value of high-risk CMD for predicting major adverse cardiovascular events (MACE) was determined using receiver-operating characteristic curve (ROC) analysis. The ROC analysis indicated that the area under the curve values for TyG was 0.708 (95% CI: 0.612-0.804, p0.05), and the optimal cutoff value was 8.09. In this study, we observed a correlation between the CMDin patients with ANOCA and TyG index demonstrating strong predictive capability for discriminating between low-risk and high-risk of CMD.