Endothelial dysfunction of peripheral arteries in patients with immunohistologically confirmed myocardial inflammation correlates with endothelial expression of human leukocyte antigens and adhesion molecules in myocardial biopsies

Objectives The aim of this study was to investigate whether myocardial inflammation (MC) and endothelial activation are associated with clinically detectable endothelial dysfunction. Background In patients with MC, immunohistologic evaluation of myocardial biopsies demonstrates a cellular infiltrate of lymphocytes in the myocardium and endothelial activation, as indicated by enhanced expression of human leukocyte antigen (HLA)-1, HLA-DR and intercellular adhesion molecule (ICAM)-1. This chronic inflammatory process may be associated with endothelial dysfunction. Methods In 65 patients with suspected MC, endothelial function of the radial artery was noninvasively assessed. By means of high-resolution ultrasound, diameter changes in response to reactive hyperemia (endothelium-dependent), as compared with glyceroltrinitrate (endothelium-independent), were analyzed. In the myocardial biopsies, MC was confirmed by immunohistology in 53 patients; 12 patients with normal myocardial biopsies served as controls. Endothelial expression of HLA-1, HLA-DR and ICAM-1 was semiquantitatively evaluated by immunohistology. To minimize other factors influencing endothelial function, patients with coronary artery disease, diabetes, severely impaired left ventricular function or more than one arteriosclerotic risk factor were excluded from this study. Results Endothelial function, as determined by flow-mediated vasodilation (FMD), in patients with MC was impaired (FMDMC 4.28%), as compared with controls (FMDCo 10.10%). The severity of endothelial dysfunction in patients with MC correlated significantly with the extent of endothelial expression of HLA-1, HLA-DR and ICAM-1 in myocardial biopsies. Endothelium-independent vasodilation was not affected by MC or endothelial activation. Conclusions Myocardial inflammation is associated with endothelial dysfunction of peripheral arteries. The severity of endothelial dysfunction correlates with the extent of endothelial activation.