Detection of acute aortic dissection by extremely high soluble lectin-like oxidized LDL receptor-1 (sLOX-1) and low troponin T levels in blood

摘要

Acute aortic dissection (AAD) is a potentially critical cardiovascular emergency and would lead to high mortality without rapid diagnosis and appropriate treatment. D-dimer measurement has been established as a standard method to diagnose AAD because of its high sensitivity. However, the diagnostic specificity appears to be insufficient, and, especially, it is not useful to make a differential diagnosis between AAD and acute myocardial infarction. Therefore, the value of D-dimer is no more than a screening tool to rule out AAD. Measurement of other suitable biomarkers, in combination with D-dimer, would be necessary to improve diagnostic accuracy for AAD, because differentiation of AAD from acute coronary syndrome (ACS), especially non-ST elevation ACS (NSTEACS), is difficult. Lectin-like oxidized LDL receptor-1 (LOX-1), a receptor for atherogenic oxidized LDL, is abundantly expressed in advanced human atherosclerotic lesions [4], which is cleaved at the membrane-proximal extracellular domain by proteases and released as a soluble form. Therefore, soluble LOX-1 (sLOX-1) is regarded as a biomarker for plaque rupture and vulnerable plaques, which can be used to diagnose ACS at the early stage. We hypothesized that LOX-1 expressed on human atherosclerotic aorta was cleaved and released as sLOX-1 by dissection of aortas with atherosclerotic plaques, and that circulating blood sLOX-1 levels are elevated in patients with AAD at the early stage. If this is the case, we would be able to use sLOX-1 to diagnose AAD in the ER. The aim of the present study is to clarify the diagnostic accuracy of plasma sLOX-1 levels in the ER for the patients with AAD.