High cholesterol levels are associated with coronary microvascular dysfunction

Abstract

Objectives: We investigated the potential association between serum cholesterol levels and coronary microvascular function, using the index of microvascular resistance (IMR), in patients with coronary artery disease.

Methods: At the time of coronary angiography, IMR was measured in one or more epicardial vessel with an intermediate stenosis (>30%). Total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein cholesterol and triglyceride concentrations were measured before cardiac catheterization.

Results: A total of 110 coronary arteries were investigated in 95 patients. The mean IMR was 26 ± 12 with evidence of microvascular dysfunction in 32 arteries (29%). A significant correlation was seen between IMR, total cholesterol (r=0.28, P=0.003) and LDL cholesterol (r=0.30, P=0.001). At multivariate analysis, LDL cholesterol was the only independent predictor of IMR, even after adjustment for the extent of epicardial coronary atherosclerosis and fractional flow reserve values.

Conclusion: Our data obtained with invasive measurement of microvascular resistance suggest a significant correlation between cholesterol levels and coronary microvascular dysfunction.