The new issue of the ACMA Medical Forum will feature an article by Howard Liu, M.D., an internist at Beth Israel Deacon Hospital, Harvard Medical School and an ACMA founding board member. Dr. Liu's article will discuss nine simple ways to reduce the risk of coronary heart disease. Coronary heart disease is the number one cause of death in the United States. Modifying your lifestyle may reduce the risk for this life-threatening disease. As we always said, your health is more important than anything else. We believe you and your families can enhance your health by following Dr. Liu's instructions.

36 year old father of two lovely girls woke up suddenly in the middle of the night with chest pain in the middle of his chest associated with sweating, nausea, and pain down his left arm. In the
emergency room, he was found to be having a heart attack and was promptly transferred to Beth Israel Deaconess Medical Center. Inside the cardiac catheterization lab, one of the three major blood vessels
(arteries) supplying the heart was occluded with blood clot. A balloon was inflated inside the artery to break up the clot and a stent (metal mesh) was inserted to keep the artery open. He was eventually pain free after the procedure. Before the heart attack, he was a very healthy construction worker who smokes two packs a day for 20 years.

Within a three week interval, another 34 year old white male presented to the Beth Israel Deaconess emergency room with chest discomfort while mowing his lawn. Because his father died of a heart attack when he was 41, he got alarmed and went to the emergency room. Electrocardiogram showed that he was having an ongoing heart attack. He was eventually free of discomfort after his blocked artery was opened with balloon and stent. He has very high cholesterol, and his 10 year old son has a cholesterol level greater than 400 (the upper limit of normal is 200).

These two true stories illustrate several important points regarding coronary heart disease (CHD), the #1 killer in the United States. Coronary heart disease is sometimes also called coronary artery disease.
There are three major arteries supplying the heart (figure 1). When fatty material builds up in the arteries or their branches, it blocks or slows the flow the flow of blood and oxygen. That in turn can cause chest pain or a heart attack (figure 2). The stories demonstrate that coronary heart disease affecting the young and the old. An estimated 14 million Americans have the disease (5 out of every 100 Americans). Those two gentlemen were lucky enough to have the blocked arteries opened up on time. In reality, 20% of those having heart attacks die before getting to the hospital. The author has relative who died of sudden cardiac death at home at his 50's. And Chinese are not immuned from this disease. In Hong Kong and Shanghai, with the adoption of more Westernized diet, CHD has surpassed cancer as the leading cause of death. The final point from the stories is that there are risk factors one can do to lower the risk of CHD, such as smoking and high cholesterol level.

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Q: What causes CHD?

A: In the famous Framingham study, in which a large group of volunteers who were free of CHD at the beginning of the study were studied for risks factors associated with development of CHD with time. Family history of CHD, high blood pressure, high cholesterol, diabetes and smoking were identified as independent risk factors. In women, post-menopausal status also increases risk of CHD. Overweight, eating a diet high in fat, and not exercising enough also are linked to CHD.

Q: What are the nine ways to decrease the risks of CHD?
A: Diet and medication to lower the cholesterol, treating high blood pressure, controlling diabetes, smoking cessation, aspirin, exercise, vitamin E, lowering homocysteine level, and hormone replacement in post-menopausal women are nine ways to decrease the risks of CHD.

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Q: What is cholesterol?

A: Cholesterol is an essential lipid of the cell membrane that confers fluidity to the cell membrane. But it is also the major component that deposits inside the wall of the coronary arteries, like rusts in a steel pipe. The higher the amount of cholesterol one consumes, the higher the cholesterol level in one's blood, and the higher the chance the "rust" will develop inside a "pipe".

Q: What is "good" and "bad" cholesterol?
A: "Bad" cholesterol or LDL (low density lipoprotein) consists of the majority of the cholesterol in the circulation. It is the one that deposits inside the blood vessels and causes narrowing. The higher the LDL, the higher the chance of having chest pain, heart attacks, and strokes. On the other hand, "Good" cholesterol or HDL (high density lipoprotein) is responsible for carrying the cholesterol back to the
liver for disposal. So the higher its content, the lower the risk of developing CHD.

Q: Which kind of food is high in cholesterol?
A: Egg, animal organs, and particular type of fish. One may not know, one egg yolk constitute almost the daily allowance of cholesterol, which is 300mg. Animal organs like liver, stomach, brain, and intestine are
also high in cholesterol content. See table 1 for detail. In a group of patients after their initial heart attacks, lower their cholesterol content in their diet together with exercise has clearly shown to reverse some of the narrowing of their coronary arteries.

Q: When should one be treated for high cholesterol?
A: If one has no CHD or has fewer than two risk factors (e.g., smoking, family history of CHD, high blood pressure, diabetes), he/she should lower the content of food high in cholesterol in his/her diet if the bad
cholesterol (LDL)>160. If LDL is persistently greater than 190 despite diet modification, medication may be needed to control LDL<160. See table 2 for additional details. Several well designed randomized,
controlled trials have demonstrated that lower cholesterol wuth medication can effectively decrease future heart attacks and deaths.

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Q: How high is "high blood pressure"? What are the risks of high blood pressure? How can one decrease the risk of deveoloping high blood pressure?

High blood pressure, or hypertension, is defined as systolic blood pressure (when the heart is pumping) >140 mm Hg or diastolic pressure (when the heart is relaxing) >90. Some patients ignore high blood pressure because hypertension usually does not cause pain or discomfort. But high blood pressure is clearly associated with higher rate of CHD, higher death rate and is the #1 risk factor for stroke (as known as "brain attack"). The author has relative in his 60's woke up unable to move his body and apparently had a stroke overnight. His only medical problem is hypertension and was totally "fine" before the event.

Studies have shown that in patients over 60 years of age, treatment reduces the incidence of CHD by 20%. In patients with diabetes, lower systolic blood pressure <135 and diastolic pressure <85 decreases heart attack by 25%, stroke by 40%, and death by 30%.

Exercise to a sweat for about 3 times a week reduces the incidence of development of high blood pressure and prolongs one's life expectancy by an estimated 2 years.

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A: The Chinese translation for diabetes is "Sugar in the Urine Disease", but the disease itself has much more damage to the body than its name suggests. It is caused by insufficient insulin secretion or the body's
resistance to insulin. That leads to high sugar level in the blood and causes damage to the cell lining of blood vessels. As a result, there is increased "rusts" built up in the blood vessels secondary to damage to
those lining cells. The consequence can be devastating. Blockage of arteries supplying the heart causes heart attack. Blockage of arteries supplying the brain causes stroke or brain attack. Blockage of arteries
supplying the legs causes pain in the legs with ambulation or even necessitates amputation because of insufficient blood supply. It can also causes blindness, kidney failure (necessitating dialysis), and
cataract.

Q: What can one do to control the diabetes and lower the risks of CHD?
A: As in the case of controlling high cholesterol, diet and medications are the key. Diet high in fat and protein calories but low in carbohydrate is important in lower the sugar level in the blood. Losing
weight by as little as 5 pounds may mean a difference between needing medications or no medications. When diet and weight loss alone can not lower the sugar level below 140, there are many different pills that physicians can prescribe to further lower the glucose. Insulin injection can be used if pills are not effective.

Studies have shown that controlling blood sugar level decreases the risk of CHD and other complication of diabetes. Also, there is significant benefits in tight control of high blood pressure in diabetic patients to
decrease the devastating complication of diabetes.

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Q: Why is smoking so difficult to control? What kind of help is  available out there to help one quit smoking?

A: Smoking is addictive. That is why so many smokers are unable to quit smoking despite well known risks associated with cigarette smoking, including CHD, stroke, sudden death, all kinds of cancers (the best known being lung cancer). And the cigarette manufacturer knows this. They hand out free cigarettes to high school students in the developing world, knowing quite well once the students are hooked, they are
"customers for life".

Recently there are two new modalities available to help smokers quit. One replaces the nicotine in the cigarette with nicotine gum or patch, thus avoiding the carcinogens in the cigarette smoke while supplying the body with nicotine. The other works on decreasing the craving associated with cigarette addiction. The newest article from the New England Journal of Medicine showed that with those two modalities, smokers can quite 2 or 3 times as readily as strong will alone.

Smokers are three times as likely as nonsmokers in getting CHD. The good news is three years after quiting smoking, the risk is down to that of nonsmokers.

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Q:  Bayer advertises in TELEVISION that Bayer Aspirin is good for the heart.
Is it good for me?

A: In the Physician's Health Study, more than 22 thousand of physicians were treated with either Aspirin or placebo. The risk of heart attack was reduced by 42% with Aspirin. But there is no difference in death
rate between and case and the control group because of slight increase risk of stroke caused by bleeding inside the head. So an Aspirin a day is probably beneficial to the heart if you have more than one risk
factor for CHD or already has documented CHD.

Q: Should I exercise? How much should I exercise?

A: Exercise is a useful therapy to reduce other CHD risk factors, including high blood pressure, high cholesterol, and diabetes. Physical inactivity is an independent risk factor for the development of CHD. And beginning an exercise program has been associated with a significant decline in CHD risk.

For those without heart or lung problem, one can start slowly with low-intensity activity, eg, walking or yard work, for at least 3 times per week. Then the activity can be slowly increase to fitness building
activities associated with sweating and a sensation of breathing hard. The duration and frequency of this activity should be at least 30 minutes and at least three times a week.

Q: Is vitamin E good for the heart?
A: The strongest case for vitamin E supplement came from the Cambridge Heart Antioxidant Study (CHAOS). In patients with CHD, vitamin E supplement is associated with fewer heart attack and death in a 18 month follow up. But the data is lacking for prevention of CHD with vitamin E in those without CHD. In the absence of known harmful effects, taking vitamin 400mg everyday may be a reasonable course of action for those wishing to lower their risk of CHD further.

Q: What is all the hoopla about folate?  What is homocysteine? 
     What is the relationship between folate and homocysteine?
A: Homocysteine is an amino acid involved in protein metabolism. High homocysteine level in the blood has recently been associated with CHD. And folate, one the the B vitamins, receives a lot of press recently
because it can readily reduce the level of homocysteine. Randomized controlled trials as primary prevention of CHD has not yet been completed. Based on the current knowledge, it is prudent to recommend that all patients maintain folate intake through diet or supplement at 400 ug everyday.

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In summary, Coronary heart disease is the number one killer in theUnited States and part of China. To prevent the development of CHD, one just has to remember the following alphabet soup: