乌鸦传媒

High levels of low or very low density lipoprotein cholesterol (LDL or VLDL) hurt your heart health and raise your risk of future health problems through a process known as atherosclerosis.

Cholesterol is used by the body for a number of important functions, but when high levels are present in the blood, deposits begin to form in blood vessels. Levels of 100 mg/dL or higher for LDL and 200 mg/dL or greater for total cholesterol are considered high for most adults, but studies have consistently shown the lower the better.

Over time, this plaque builds up with immune cells and smooth muscle cells in the vessel wall, leading to inflammation. Calcified areas often develop as the plaque evolves. This process makes the arteries thick and stiff.

Over the years, the atherosclerotic plaques initially grow outward to make the entire artery larger but then begin to grow into the space where blood flows. After the blockage (stenosis) fills more than 60% of the width of the blood vessel, it can limit blood flow to your organs. The plaque could also burst and cause a blood clot to block blood flow entirely to an organ or tissue, causing a medical emergency.

Atherosclerosis in vessels in the heart causes chest pain and a feeling of pressure when you're under stress or active. Blockages there can also cause a heart attack, or myocardial infarction.

Blockages of the vessels leading to the brain can cause a stroke or transient ischemic attack. When atherosclerosis affects vessels in your arms or legs, it causes peripheral artery disease, with symptoms of leg pain when walking (claudication) or low blood flow that can lead to poor wound healing and even amputation.

Another potential problem from atherosclerosis is blockage of the arteries leading to the kidneys (renal artery stenosis), which can raise your blood pressure, impact urination, and cause swelling. Blockage of arteries into the digestive system (mesenteric ischemia) can cause painful cramping, diarrhea, and nausea.

Altogether, complications of atherosclerosis are the leading cause of death worldwide. More than half of Americans ages 45 to 84 have atherosclerosis without knowing it, according to data from an ethnically diverse .

Read Part 1 of this series: For Your Patients: Hypercholesterolemia: Understanding Your Diagnosis

"Medical Journeys" is a set of clinical resources reviewed by doctors, meant for physicians and other healthcare professionals as well as the patients they serve. Each episode of this journey through a disease state contains both a physician guide and a downloadable/printable patient resource. "Medical Journeys" chart a path each step of the way for physicians and patients and provide continual resources and support, as the caregiver team navigates the course of a disease.