Atherosclerosis Endothelial dysfunction may be involved in the development of
atherosclerosis and may predate vascular pathology. Endothelial dysfunction may also lead to increased adherence of
monocytes and
macrophages, as well as promoting infiltration of
low-density lipoprotein (LDL) in the vessel wall.
Oxidized LDL is a hallmark feature of atherosclerosis,
Dyslipidemia and
hypertension are well known to contribute to endothelial dysfunction, and lowering blood pressure and LDL has been shown to improve endothelial function, particularly when lowered with
ACE inhibitors,
calcium channel blockers, and
statins. Steady laminar flow with high shear stress in blood vessels protects against atherosclerosis, whereas disturbed flow promotes atherosclerosis. As a co-factor for
nitric oxide synthase,
tetrahydrobiopterin (BH4) supplementation has shown beneficial results for the treatment of endothelial dysfunction in animal experiments and clinical trials, although the tendency of BH4 to become oxidized to BH2 remains a problem. Current measurements of endothelial function via FMD vary due to technical and physiological factors. Furthermore, a
negative correlation between percent flow-mediated dilation and baseline artery size is recognised as a fundamental scaling problem, leading to biased estimates of endothelial function.
Forearm plethysmography has replaced flow mediated dilation for assessing endothelial dysfunction.
von Willebrand factor is a marker of endothelial dysfunction and is consistently elevated in
atrial fibrillation. A non-invasive,
FDA-approved device for measuring endothelial function that works by measuring
Reactive Hyperemia Index (RHI) is
Itamar Medical's EndoPAT. It has shown an 80% sensitivity and 86% specificity to diagnose
coronary artery disease when compared against the gold standard, acetylcholine angiogram. This result suggests that this peripheral test reflects the physiology of the
coronary endothelium. Since NO maintains low tone and high compliance of the small arteries at rest, a reduction of age-dependent small artery compliance is a marker for endothelial dysfunction that is associated with both functional and structural changes in the microcirculation. Small artery compliance or stiffness can be assessed simply and at rest and can be distinguished from large artery stiffness by use of pulsewave analysis.
Endothelial dysfunction and stents Stent implantation has been correlated with impaired endothelial function in several studies.
Sirolimus eluting stents were previously used because they showed low rates of in-stent
restenosis, but further investigation showed that they often impair endothelial function in humans and worsen conditions.
COVID-19 complication in the lungs COVID-19 can present with an acute lung injury manifestation that arises from endothelial dysfunction.
Risk reduction Treatment of
high blood pressure and
high levels of cholesterol in the blood may improve endothelial function in people taking
statins (HMGCoA-reductase inhibitor), and
renin angiotensin system inhibitors, such as
ACE inhibitors and
angiotensin II receptor antagonists. Calcium channel blockers and selective beta 1 antagonists may also improve endothelial dysfunction. == See also ==