Dr. Lee was born in Shanghai, China, and received his college and medical training in the United States. He is fluent in English and three Chinese dialects. He graduated with chemistry departmental honors from Harvey Mudd College. He was appointed president of AOA society at UCLA School of Medicine. He underwent internal medicine residency and gastroenterology fellowship training at Cedars Sinai Medical Center.
Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.
In order to lower LDL cholesterol, the activity level of the LDL receptors
must be increased. LDL receptor activities can be increased by diets that are
low in cholesterol and saturated fats and by medications.
Therapeutic lifestyle changes to lower cholesterol
Lowering LDL cholesterol involves losing excess weight, exercising regularly,
and following a diet that is low in saturated fat and cholesterol. (Please visit
the Therapeutic Lifestyle Changes (TLC) section
(http://www.nhlbi.nih.gov/chd/lifestyles.htm) for more detailed information on
diet and exercise to lower blood cholesterol.)
Medications to lower cholesterol
Medications are prescribed when lifestyle changes cannot reduce the LDL
cholesterol to desired levels. The most effective and widely used medications to
lower LDL cholesterol are called statins. Most of the large controlled trials
that demonstrated the heart attack and strokeprevention benefits of lowering
LDL cholesterol used one of the statins. Other medications used in lowering LDL
cholesterol and in altering cholesterol profiles include nicotinic acid
(niacin), fibrates such as gemfibrozil (Lopid), resins such as cholestyramine
(Questran), and ezetimibe, Zetia. (An in-depth discussion of these drugs is
presented in this article starting at the heading: What are the statin drugs?)
There are no established "normal"
blood levels for total and LDL cholesterol. In most other blood tests in
medicine, normal ranges can be set by taking measurements from large number of
healthy subjects. For example, normal fasting blood sugar levels can be
established by performing blood tests among healthy subjects without diabetes
mellitus. If a patient's fasting blood glucose falls within this normal range,
he/she most likely does not have diabetes mellitus, whereas if the patient's
fasting blood sugar tests higher than the normal range, he/she probably has
diabetes mellitus and further tests can be performed to confirm the diagnosis.
Medications, such as insulin or oral diabetes medications can be prescribed to
lower abnormally high blood sugar levels.
Unfortunately, the normal range of LDL
cholesterol among "healthy" adults (adults with no known coronary heart disease)
in the United States may be too high. The atherosclerosis process may be quietly
progressing in many healthy adults with average LDL cholesterol blood levels,
putting them at risk of developing coronary heart diseases in the future.
What are desirable cholesterol blood levels?
Since no "normal" cholesterol levels
have been established, doctors rely on "desirable cholesterol levels" in making
treatment recommendations. However, the "desirable" levels of total cholesterol
and LDL cholesterol have been moving targets; they have been steadily declining
over the years as more and more controlled trials have demonstrated that the
risk of heart attacks and strokes can be reduced further with lower LDL
cholesterol levels.
In 1985, the National Heart, Lung, and Blood Institute
(NHLBI) of the National Institutes of Health gathered a panel of cholesterol
experts to form the National Cholesterol Education Program (NCEP). This expert
panel reviewed data mainly from large controlled cholesterol-lowering trials,
and published their blood cholesterol treatment recommendations in two separate
reports; one published in May, 2001, the other in June, 2004.
The NECP report
published in May 2001 is called the Adult Treatment Panel III (ATP III). This
report included desirable anvcd undesirable levels for LDL cholesterol, HDL
cholesterol, and triglycerides (see below), as well as LDL cholesterol lowering
target goals.
Since the publication of the ATP III report in 2001, several large
controlled trials have been published, showing that aggressively lowering LDL
cholesterol further reduced heart attacks and strokes. Therefore in June, 2004,
the expert panel lowered the LDL cholesterol targets, especially for patients
who have very high risks of developing heart attacks (see below).
Optimal, undesirable, and desirable lipid levels (published in 2001)
LDL cholesterol (mg/dl) <100 Optimal 100-129 near or above optimal 130-159 Borderline high
160-189 High > 190 Very high
Total cholesterol (mg/dl) <200 Desirable 200-239 Borderline high >240 High
HDL cholesterol (mg/dl) <40 Low (undesirable) >60 High (desirable)
Triglycerides (mg/dl) <150 Normal 150-199 Borderline-high 200-499 High >500 Very high
Angina is chest pain that is due to an inadequate supply of oxygen to the heart muscle.
Angina can be caused by coronary artery disease or spasm of the coronary
arteries. EKG, exercise treadmill, stress echocardiography, stress thallium, and cardiac
catheterization are important tests used in the diagnosis of angina.
Cholesterol is naturally produced by the body, and is a building block for cell membranes and hormones. Low-density lipoprotein (LDL) cholesterol is the "bad" cholesterol, conversely, high-density lipoprotein (HDL) cholesterol is the "good" cholesterol. High cholesterol treatment includes lifestyle changes (diet and exercise), and medications such as statins, bile acid resins, and fibric acid derivatives.
Heart attack happens when a blood clot completely obstructs a coronary
artery supplying blood to the heart muscle. A heart attack can cause chest pain, heart failure, and electrical
instability of the heart.
Rhabdomyolysis is a rapid deterioration and destruction of skeletal muscle. Some of the causes of rhabdomyolysis include severe burns, muscle trauma, coma, seizures, electrolyte imbalance, medications (statins), viruses, bacteria. Treatment of rhabdomyolysis depends on the cause.
Peripheral vascular disease (PVD) refers to diseases of the blood vessels (arteries and veins) located outside the heart and brain. While there are many causes of peripheral vascular disease, doctors commonly use the term peripheral vascular disease to refer to peripheral artery disease (peripheral arterial disease, PAD), a condition that develops when the arteries that supply blood to the internal organs, arms, and legs become completely or partially blocked as a result of atherosclerosis. Peripheral artery disease symptoms include: intermittent claudication, rest pain, numbness in the extremities, and more. Treatment for peripheral artery disease include: lifestyle measures, medication, angioplasty, and surgery.
When a portion of the brain loses blood supply, through a blood clot or embolus, a transient ischemic attack (TIA, mini-stroke) may occur. If the symptoms do not resolve, a stroke most likely has occurred. Symptoms of TIA include: confusion, weakness, lethargy, and loss of function to one side of the body. Risk factors for TIA include vascular disease, smoking, high blood pressure, high cholesterol, and diabetes. Treatment depends upon the severity of the TIA, and whether it resolves.
Heart attacks are the major causes of unexpected, sudden death among men and women. A heart attack is also a significant cause of heart failure. Learn the risk factors for heart attack such as high blood pressure, diabetes, and other heart conditions. Lowering your risk factor, lifestyle changes, and in some cases medication are the most effective way of preventing a heart attack.
A heart attack is a layperson's term for a sudden blockage of a coronary artery. This photo essay inlcudes graphics, pictures, and illustrations of diseased heart tissue and the mechanisms that lead to coronary artery disease, and possible heart attack.