HomeHealthArchivesMar 2007

 

 

Heart Disease

1. Tell me about how common heart disease is in our country:

The Book Proof Positive by Neil Nedley, M.D. provides some useful information on this disease. In America, heart disease is the leading killer of men and women alike. Despite all that medical science knows about how to prevent this disease, recent statistics show that over 954,000 people died of diseases of the heart and blood vessels (cardiovascular disease) in the United States alone in 1994, up from 925,000 in 1992. Since 1900 the number one killer in the United States has been cardiovascular disease in every year but one (1918). When an airline crashes in the U.S. and hundreds of people die, the news is filled with this top story for days. In-depth analysis is performed and broadcast regarding the possible cause of the crash and how it might have been prevented. Consider that approximately 2600 deaths, many of them as sudden as in an airline crash, occur each day in the U.S. from cardiovascular disease alone. This is greater than 10 jumbo jet crashes per day. Yet, these deaths do not even make the news broadcasts except when a famous person dies from a heart attack, and then if the disease is mentioned at all, it is only as an afterthought, as if it was inevitable. The number one cause of death deserves more thorough attention in America.

Sadly, deaths only tell part of the story of this dreadful disease. Of the current U.S. population of about 258 million, more than 57 million people have some form of this disease. The annual cost to America for diseases of the heart and blood vessels is an astounding 259.1 billion dollars, which includes not only the medical and surgical treatment, but also lost productivity in the work force. If you personally happen to survive a stroke, the average lifetime cost in medical bills and lost earnings will be $103,576.6 How much better to prevent a stroke or a heart attack than to pay for one and still suffer the diminished quality of life that is almost certain to follow! No wonder Clyde Yancy, M.D., president of the American Heart Association's Dallas division and researching cardiologist at the University of Texas Southwestern Medical Center in Dallas said recently, "No matter where somebody is in their maturity process, young, middle-aged, or old, incorporating a heart-healthy lifestyle is the most cost effective thing that can be done right now." Not only is it cost effective, but even more important will likely be life saving, and certainly will be life-enhancing!

2. Tell me about the function of the heart in our body:

The heart is composed of four main chambers. Two smaller atria and two large ventricles. The blood from most of the body enters the right atrium, is pumped into the right ventricle and is then pumped through the lungs. This is where blood picks up oxygen and gets rid of carbon dioxide. The blood then enters the left atrium, is pumped into the left ventricle, and the left ventricle pumps the oxygenated blood to fill needs in the body.

3. How does the heart get oxygen?

There are special arteries in the heart called coronary arteries that supply the heart muscle. There are typically 3 main division: 2 from the left coronary artery and the right coronary artery.

4. What is involved in coronary artery disease?

Yes, when we speak about coronary artery disease we are usually speaking about disease of these arteries, the coronary arteries of the heart. If one or more of these arteries becomes blocked, then a part of the heart muscle may die. This is a heart attack.

5. What is the process that leads to a heart attack?

There is more to the process of atherosclerosis than the buildup of fat. When fat accumulates on the inside of the coronary arteries (or any other artery), the body reacts to prevent a blood clot. It covers those fatty deposits with a tough, fibrous cap. This is an important response, because if fatty material is allowed to come into direct contact with the blood it can stimulate the blood to clot. The fibrous cap protects against this deadly clotting. In fact, this dual process gives atherosclerosis its name. "Athero" refers to the "mushy" or "gruel-like" fatty material that builds up inside the arteries. "Sclerosis" describes the hard fibrous material made by the body in response.

Unfortunately, an atherosclerotic plaque can ulcerate, causing a break in the protective cap. When this happens, a combination of fibrous and fatty material is released into the blood stream. A now smaller, eroded fatty deposit, called an ulcerated plaque (sometimes called "lesion"), remains attached to the artery wall. Both the liberated fatty material and the ulcerated plaque itself can activate platelets, the body's clotting cells. This often sets in motion a chain of events that can completely obstruct any artery that is already significantly narrowed by atherosclerosis. If this or another process results in complete obstruction of a coronary artery, the heart muscle that was dependent on the blood flow in that artery will die. And as we mentioned earlier, this death of heart tissue is called a myocardial infarction (MI), or heart attack.

6. This atherosclerosis or hardening or the arteries occurs in other arteries than just those in the heart doesn't it?

Yes, the process of atherosclerosis is not confined to the heart arteries. The term "coronary artery disease" refers specifically to the gradual narrowing of atherosclerosis as it affects the heart arteries. Large and medium sized arteries throughout the body can become narrowed by this buildup of fatty material as a plaque is formed.

7. Why is a heart attack so serious if there is a lot of heart muscle left over to keep pumping?

The heart is an electrical organ. A heart attack can disturb this electrical function.

As a result of the lack of symptoms, heart disease is often not detected in its earlier stages. A person may feel great, be working full time, and yet be on the verge of a major heart attack and perhaps even sudden death. Approximately 60 percent of heart attack deaths occur suddenly or outside of a hospital before treatment can be administered. Over half of all sudden deaths (almost two-thirds of sudden death cases in women) occur in individuals who were not previously diagnosed with coronary artery disease. It is a sobering reality for many that their first heart attack is their only heart attack. Sudden death offers no second chances.

8. How does the electrical function of the heart work?

The cells in the heart are stimulated to contract by an electrical signal, this signal comes from a place called the SA node in the normal heart. The SA node sends the signal out through the upper heart, the signal then goes through a passageway to the lower heart, the AV node. The AV node then allows a normal signal to go to the large ventricles where most of the pumping is done.

9. What goes wrong when the electrical signal doesn't work properly?

Sometimes the electrical signal becomes disorganized, instead of an organized signal starting at the SA node, passing down through the ventricles and ending, the electrical signal may go spinning around the heart very quickly. If this happens in the top part of the heart it may represent a common condition called atrial fibrillation. If this happens in the bottom part of the heart, then it might cause something called ventricular fibrillation. While many people live for years with atrial fibrillation, ventricular fibrillation is typically fatal in minutes if not stopped.

10. What causes a person to go into atrial fibrillation or ventricular fibrillation?

Atrial fibrillation as mentioned earlier is fairly common, and is caused by multiple conditions: high blood pressure over many years' duration may cause the left atrium to slowly stretch larger and larger, when it reaches a large enough size, there is a risk for the electrical signal to become disorganized. Overactive thyroid condition-hyperthyroidism, or abnormalities in the blood minerals may contribute to the problem. Atrial fibrillation carries a risk of blood clots being sent through the arteries of the body and causing blockages in important arteries such as the brain arteries. If a clot enters the brain blood vessel system, a stroke might result. So people often take medication to keep the blot from making clots when they have atrial fibrillation.

Ventricular fibrillation is an immensely more serious condition as we mentioned above. It seems to occur more easily in people who have weak hearts, diseased hearts, and especially in hearts of people who have just had a heart attack within seconds to a couple of days before it starts. This is one of the reasons that it is important to receive medical care very early in a heart attack. If ventricular fibrillation occurs where a person is in a high-level hospital unit such as an intensive care unit or an emergency room in the hospital, a person may be able to be treated for ventricular fibrillation and survive.

11. You mentioned that treatment of Ventricular fibrillation is one reason to be treated early in a hospital for heart attack, is there another?

Yes, since a heart attack is a blockage of one of the arteries that feeds the muscle of the heart, some of the muscle that had previously been supplied by that artery is probably starving for nutrition and oxygen after the blood supply is blocked. But much of that starving muscle might be saved if the artery can be opened up quickly. Opening up of blocked arteries is something that can be accomplished often in a hospital if a person shows up quickly after having a heart attack. When the artery is quickly opened up, the muscle that was starving can be nourished again, and much of it can live.

12. What can a person do after having a heart attack and having the artery opened?

There are then several different avenues possible for treatment of that narrowed artery. Some people might benefit from surgery, some people might have a procedure where a balloon is placed inside of the narrowed artery, blown up, and a stent used to help to keep the artery open. Some people might be told to use "medical therapy."

13. What is medical Therapy?

Medical therapy is basically treatment other than surgery. Medications are often used in this setting.

14. What is the purpose of using Medications?

Medications are used to lower the blood pressure and perhaps the pulse rate so that the heart doesn't have to work as hard. They are also used to lower the cholesterol to reduce the rate of build-up of plaque that caused the narrowing in the first place. Medication might also be used to decrease the chance of blood clot starting that might block an artery in the future.

15. You mentioned that medication is used to lower the blood pressure, perhaps lower the pulse, and lower the cholesterol. Aren't those things that I have some control over by the way that I eat or exercise?

Yes they are. In fact we know that people can usually prevent heart disease by a healthful lifestyle such as good diet and regular exercise.

16. But is it true that once people get the disease in their arteries, they have missed out on the opportunity to benefit much from lifestyle.

No, not all! In fact smokers who quit smoking after a first heart attack may decrease risk of their next heart attack dramatically. People who follow a very low fat diet may start reversing the disease in their heart arteries. Dr. Ornish has had some impressive results with people even in severe heart disease.

17. What if I want to prevent heart disease?

There are some factors that influence our risk of heart disease that we can do nothing about. For example, age and sex cannot be changed, yet they have a significant bearing on cardiovascular risk. The older we are, the greater our risk. Similarly, men are at higher risk than women of the same age-particularly in the years before menopause. Fortunately, however, medical research demonstrates that we can change a number of factors that influence our risk of heart disease. The three most important modifiable heart disease risk factors are cigarette smoking, high blood pressure, and high cholesterol.

Addressing all three can make a considerable impact, as was illustrated by a study of some 29,000 Finnish men and women over a 20-year period (1972 to 1992). When these individuals lowered the cholesterol in their diets, lowered their blood pressure, and stopped their tobacco use, they reduced their heart attack risk by more than half.

18. How important is smoking as a risk factor, and is it worth quitting now that the damage might already be done?

Studies show that those who are between the ages of 45 and 54 and smoke more than one pack per day increase their risk of a heart attack by over four times. Older smokers increase their risk between 70 and 200 percent depending on their age. Moreover, when combined with other risk factors such as high cholesterol and hypertension, the effect of smoking is even greater, according to a summary of studies on smoking published by the Pooling Project Research Group.

Many find the strong relationship between smoking and heart disease deaths hard to accept. Nonetheless, the statistical research is clear. Among Americans who are under 65, smoking is responsible for fully 45 percent of male heart attack deaths and 41 percent of female heart attack casualties. In younger women, the risks may be even greater. One researcher suggests that about 76 percent of heart attacks in young women are due to cigarette smoking.

Not only are smokers more likely to have a heart attack, they are more likely to die from one. Furthermore, they are at higher risk from sudden death due to heart disease. When death occurs within 24 hours of some distinct change in an individual's state of health, it is called sudden death.

Smokers have up to four times the risk of sudden death compared to nonsmokers. Fortunately, however, the risk diminishes dramatically when a person stops smoking. In fact, so quickly does the risk fall that within one year the risk of sudden death from a heart attack has dropped 50 percent.

Why is there such a rapid decrease in sudden death risk? One of the answers seems to lie with nicotine. Nicotine in cigarettes increases the risk of sudden death by predisposing to fatal heart rhythm problems. In other words, if a smoker has a heart attack, sudden death is more likely because nicotine in the blood renders the heart more irritable. Nicotine, however, is rapidly cleared from the blood once a person stops smoking. Within just a few days of the last cigarette, we would therefore expect a person to be at much lower risk of death from a heart attack.

Your clotting system also rapidly changes when you stop smoking. One of the key actors in this process is the platelets. What are the platelets and what is their function? Platelets are very tiny substances in our bloodstream that are smaller than white or red blood cells. They go into action when a blood vessel is cut. Without platelets, a cut would continue to bleed until it was fatal. Platelets prevent this from happening by clumping together and sealing off the cut. The clump (or clot) grows until it is large enough to seal the broken blood vessel, stopping the bleeding. Platelets do a wonderful work for the body in sealing off broken blood vessels, usually within minutes.

These clotting cells become stickier and tend to clump in an unnatural way when a person smokes. They tend to clump inside a vessel where there is no cut, usually at places where the blood vessels narrow down. If the narrowing is located in a coronary artery or the blood vessel that carries blood to the brain, clumped platelets may stop the flow of blood. This may affect the control of limbs, affect speech, or even result in sudden death. When a person stops smoking, platelet function begins to return to normal-in just a matter of days. Since the average platelet only lives 10 days, in less than two weeks you will have a whole new population of normal platelets in the body. These changes seem to play a significant role in decreasing heart disease risk within a short time of stopping smoking.

Smoking also affects more conventional heart disease risk factors. Research indicates that smoking tends to both lower the "good cholesterol," HDL, and raise the "bad cholesterol," LDL.

The facts regarding heart rhythm stabilization and normalization of clotting function should provide further encouragement for smokers to kick the habit.

An aortic aneurysm is one particularly devastating consequence of this process of fatty buildup in the arteries. The aorta is the large blood vessel in the center of the body that carries blood away from the heart to the legs. If this major vessel is severely affected with atherosclerosis, it can be weakened and lose its ability to tolerate the high pressures generated by the heart. In this situation, the aorta tends to balloon outward like a weak spot on a tire. That ballooning is called an aneurysm. Under the persistent high pressures that result from normal heart pumping, the aortic aneurysm will continue to grow in size until it ultimately ruptures. If that happens, the result is usually sudden death. Medical research confirms that cigarette smoking is a major cause of this fatal disease.

19. How important is blood pressure as a risk factor

A relatively small reduction in blood pressure has a significant impact on disease of the heart and blood vessels. It is astounding to consider the implications if all Americans with high blood pressure would lower their blood pressures by just 3 mm. At least 27,500 lives would be saved each year, not to mention the many more people whose lives would not be markedly worsened as a result of living through a stroke or heart attack. These facts, combined with the other information that we have examined so far, should motivate us to do everything we can in our own lives to prevent or correct high blood pressure.

People taking antihypertensive drugs have higher rates of heart disease than people who have identical blood pressures without drugs.

20. Does this mean that I shouldn't take my blood pressure medication?

I strongly recommend that prescribed blood pressure medication be taken on a regular basis. For those eager to obtain the freedom and possible additional of controlling blood pressure through lifestyle; with monitoring by a doctor, the medication may be tapered off when the lifestyle changes have impacted the body favorably enough to allow this.

21. How can I lower my blood pressure?

Aerobic exercise-exercise that calls into play the heart and lungs-significantly lowers blood pressure in hypertensive patients. In one study, eighteen sedentary individuals with high blood pressure completed a 16-week exercise program. During the program, they rode an exercise bicycle three days a week for about 45 minutes per day. They exercised at a moderate intensity (60 to 80 percent of their predicted maximum heart rate). After the four-month program, the average systolic blood pressure fell 7 mm and the average diastolic pressure, 5 mm. The exercise program also helped to prevent their blood pressure from rising as high during exercise. Their average systolic blood pressure when exercising was 19 mm lower and diastolic 10 mm lower than before the program.

If you want to use lifestyle to lower your blood pressure, you will want to make the following changes:

      1. Eat plenty of fruits, vegetables, grains, and unsalted nuts in moderation, and other low sodium foods.

      2. Avoid foods such as dill pickles, cured ham, Chinese rice, bouillon, and other high sodium foods. Read the labels.

      3. Avoid low fiber foods such as meat and dairy products.

      4. Eliminate coffee, cola drinks, and alcohol from the diet.

      5. Stop smoking.

      6. Keep the saltshaker at rest.

      7. Bring your weight down to the recommended level for your height and build.

      8. Adopt an aerobic exercise routine, such as brisk walking.

      9. Learn to cope with stress.

22. How important is cholesterol as a risk factor?

Elevated blood cholesterol levels are closely associated with fatal heart disease. Cholesterol in the diet will raise blood cholesterol levels. There are a number of other factors, however, that contribute to elevated cholesterol levels. Some of these factors were clarified by one of the great cholesterol pioneers, Dr. Ancel Keys. In the 1960s, Dr. Keys demonstrated his ability to predict with astounding accuracy the average blood cholesterol levels of population groups. All he used was a knowledge of their habitual diets in order to make his startling predictions. Unfortunately, there was too much genetic variability from person to person to do this on an individual basis. However, when looking at large groups of people, the average genetic tendencies tended to be similar from one population to the next. Thus, Keys could make his cholesterol predictions based on habitual food choices alone-without dealing with genetics. He devised a mathematical formula that fit the data. This equation is often referred to as the "Keys Equation. Without going through the calculations, Dr. Keys proves with this equation that, apart from genetics, our blood cholesterol level is determined by our diet, and essentially only three variables in the diet: saturated fat (S), polyunsaturated fat (P), and cholesterol (C).

Many people do not understand the difference between the two fats. Imagine that you are sitting in front of two 10-gallon glass fish tanks. Each tank is filled with fat. One is filled entirely with saturated fat, and the other with polyunsaturated. It would be easy to tell the difference between the two. The saturated fat would be solid at room temperature and the polyunsaturated fat would be liquid. Generally, the more solid the fat, the more saturated it is. Most fats from animal products are predominately saturated, while most plant products are high in polyunsaturated fats. We will look at specific examples shortly.

With a basic understanding of the three terms used in the Keys equation, let me now explain what the equation tells us. First, it asserts that both saturated fat and cholesterol in the diet tend to raise blood cholesterol levels. Second, it makes the point that saturated fat is much more potent at raising your blood cholesterol than even dietary cholesterol itself. Third, polyunsaturated fat tends to lower cholesterol in the blood. However, saturated fat has twice the power to raise your cholesterol as polyunsaturated fat has to lower it. Expressed another way, to cancel out the cholesterol-raising effects of a given amount of saturated fat, you would have to eat twice as much polyunsaturated fat. This fact can be used to judge whether the fat content of a given food will raise or lower your blood cholesterol level. Since all naturally occurring foods have a combination of fats in them (both polyunsaturated and saturated), you can divide the amount of polyunsaturated fat in the food by the amount of saturated fat in it, and end up with what is called a "P to S ratio" (abbreviated "P/S ratio"). If this P/S ratio is greater than 2.0, the fat in the food will tend to lower one's blood cholesterol level. Be aware that this ratio tells us nothing about other factors in the food (like cholesterol itself, for example) that may affect a person's cholesterol level.

Since a high P/S ratio in our diet will tend to lower the blood cholesterol, being aware of P/S ratio trends of common foods may be helpful.

Many of the animal products such as beef, venison (deer), lamb, and bacon have extremely low P/S ratios. These foods, based on their fat content, will tend to dramatically raise an individual's serum cholesterol. Thus, red meats are undesirable not only because they contain cholesterol, but their harmfulness is compounded because they contain so much saturated fat, and so little polyunsaturated fat. The same is true of milk, butter, and cheese. Chicken and turkey have less saturated fat than red meats, but their P/S ratios are still lower than two to one, so they, too, will raise cholesterol levels. One of the greatest myths is that chicken, turkey, and fish lower a person's cholesterol level. These foods actually raise a person's cholesterol, but they raise it less than red meat does. As a result, a person's cholesterol may go down when leaving off red meat and substituting fish and fowl. But the drop in cholesterol level occurs because chicken, turkey, and fish raise one's cholesterol level less than red meat, not because they have a cholesterol-lowering effect.

As early as the 1940s it was discovered that not all cholesterol was the same in its likelihood of causing atherosclerosis. Dr. Chaikoff and associates found that chickens that were fed large amounts of cholesterol developed high blood cholesterol levels and a considerable amount of atherosclerosis. On the other hand, chickens that were given hormones to raise their cholesterol to similar levels had virtually no fatty buildup in their arteries.

23. How can I reduce my cholesterol levels?

How can we improve our cholesterol levels? Specifically, how can we decrease total cholesterol and LDL and at the same time raise HDL? The answer to this question is extremely important. To fully appreciate the answers, however, we must make sure we understand where cholesterol comes from.

It is of primary importance that we recognize that our livers manufacture more than enough cholesterol for all our body functions. For this reason, we do not need to eat any cholesterol whatsoever. In other words, cholesterol is totally unnecessary in the human diet. However, many of us get significant amounts of cholesterol from our foods. In fact, the average American eats about 300mg of cholesterol every day. Where does all this cholesterol come from? Figure 13: Sources of Dietary Cholesterol gives us the answer in simple terms.

Note that all the cholesterol we eat comes from animal products. It is critical that we understand that fruits, vegetables, grains, and even nuts contain no cholesterol. If the food comes exclusively from plant products, then it has no cholesterol in it. On the other hand, if the food product comes from an animal, it almost always has cholesterol in it. (A few exceptions exist where the cholesterol-containing portion of the animal product has been removed. Egg whites would be the main example of this.)

Although most people may be aware that organ meats such as liver and kidney are among the most intense sources of cholesterol, many still do not understand the basic prevalence of cholesterol in animal foods. They think that if they eat chicken, turkey, or fish they are not getting cholesterol. On the contrary, we see that every animal product contains cholesterol. Also, take note that chicken contains about the same amount as pork and beef. This bad news about "white meat" has not received much press. Furthermore, many kinds of fish have a high cholesterol content.

To what extent does our intake of cholesterol affect our blood cholesterol level? The more cholesterol we eat, the higher our blood cholesterol tends to be.

As our intake of cholesterol increases, it is reflected as an increase in serum cholesterol. An increase of 75 points can occur if we consume 900 mg per day. If our intake is greater than 900 mg, not much further increase in serum cholesterol occurs. Fortunately, our bodies have protective mechanisms to keep blood cholesterol from going sky high after consuming extremely large amounts of cholesterol. We can dramatically drop our cholesterol level by decreasing cholesterol intake substantially below that 900 mg daily level. For example, dropping the cholesterol in your diet from 900 mg to 200 mg daily may lower your cholesterol 50 or 60 points. You get even more benefit when you drop your cholesterol below 200. Going from an intake of 200 mg per day down to no cholesterol in your diet may drop your blood levels another 20 points. The important message is that you can dramatically lower your cholesterol by removing all cholesterol (all animal products) from your diet.

Typical Sources of Dietary Cholesterol

Americans get most of their cholesterol from meat and eggs:

About 35 percent of the cholesterol consumed in America each day comes from meat, fowl, and fish, and another 35 percent comes from eggs. The cooking fats and oils that contain cholesterol are animal in origin, such as butter, lard, and other fats. Commercial baked goods tend to use lard, which accounts for eight percent of the cholesterol consumed per day.

Cholesterol intake might be lowered by 70 percent just by eliminating eggs, red meat, poultry, and fish. Of course we can lower it even further just by eliminating more of the animal products. If we really want to eliminate all the cholesterol in our diet, essentially all animal products must go.

In contrast to animal fats, vegetable fats have no cholesterol at all. There are different kinds of vegetable fats, and all but a few are highly polyunsaturated. Coconut has a P/S ratio of 0.01. This is a highly saturated fat and will tend to raise cholesterol levels. Although coconut has no cholesterol, its saturated fat content dramatically increases blood cholesterol. On the other end of the spectrum, walnuts with a P/S ration of 10.33 can have a rather dramatic effect in lowering an individual's cholesterol.

Most nuts, in view of their fat content, are "heart healthy" foods. Nuts in general have been studied extensively and have been found not only to lower blood cholesterol levels, but also to provide a corresponding decrease in the risk of heart disease.

Fiber in our food will help lower cholesterol. Most Americans eat far less than the recommended 25 to 30 grams per day. Evidence now suggests that a low fat, high fiber, high carbohydrate diet offers a number of advantages. Eating at least 30 to 40 grams of fiber per day from a variety of plant foods might lower your risk of heart disease, cancer, intestinal disorders, and other diseases.

Different categories of fibers include celluloses, hemicelluloses, lignin, pectins, gums, mucilages, and algal polysaccharides.

A simpler classification of fiber divides fiber types simply into water soluble and insoluble fibers. It is the water-soluble fibers that are particularly valuable for lowering cholesterol.

Fruits, vegetables, nuts, grains, and legumes, all in their natural, unrefined state, are the five main food groups that contain this cholesterol-lowering fiber. Examples of such water-soluble fibers are oat bran and fruit pectin. These compounds work by binding to cholesterol and bile acids (excreted by the liver) in the small intestine, thus preventing their absorption. Fortunately, neither bile nor cholesterol is absorbed high in the intestinal tract, but rather in the distal ileum (the last part of the small bowel). This allows the fiber plenty of time to bind up these compounds. If, however, adequate fiber is lacking, both bile and cholesterol are reabsorbed into the blood stream, raising blood cholesterol levels. Bile acids are actually made from cholesterol by the liver. As a result, the more bile you lose in the stool, the more cholesterol the body must utilize to make new bile acids that are necessary for fat digestion.

The medical literature is replete with examples of fiber's health-giving benefits. One study, published in 1992, found that adding 15 grams of fiber per day to the diet lowered serum cholesterol by 15 percent.