Learn About Your Heart...
Made Simple


By Nicolas Shammas, MD


A new, comprehensive sourcebook for
heart and vascular disease patients

Cardiovascular Health Topics



1.
Statistics about Heart and Blood Vessel Diseases in the United States
2.
Structure and Function of the Heart and Blood Vessels
3.
Diseases of the Blood Vessels of the Heart
4.
Surgical Therapies for the Cardiovascular Patient
5.
Peripheral Vascular Disease
6.
Diseases of the Blood Vessels of the Head and Neck
7.
Strokes: How to Survive Them and How to Prevent Them
8.
Valvular Heart Disease
9.
Heart Rhythms: How to Recognize Them and Treat Them
10.
Congestive Heart Failure
11. Understanding Cardiomyopathy, or Weak Heart Muscle
12. Children and Heart Disease
13. Diseases of the Pericardium
14. Systemic Illnesses, Infections and Drugs that Affect the Heart
15. Erectile Dysfunction: a Vascular Disease
16. Cardiovascular Disease Prevention
17. Heart Healthy Nutritional Tips
18. Cardiac Rehabilitation
19. Medications for Cardiovascular Disorders
20. Heart Tests You Need to Know
21. Learn What to Do in a Medical Emergency
22. How to Choose Your Doctor and Hospital
23. Medical Research and How You Can Get Involved
24. Taking the Next Step — A Few Community Resources to Help You Live More Healthfully
25. How Much Did You Learn from This Book: Take a Simple Test



CARDIOVASCULAR DISEASE PREVENTION

Peter P. Toth, MD, PhD, FAAFP, FACC

What is coronary heart disease (CHD)?

Heart disease is the leading cause of death and disability for men and women in industrialized nations. The onus on heart disease prevention is increasing. The economic and human cost of heart disease is staggering. In 2002, the cost of treating coronary heart disease (CHD) was over $112 billion in the United States alone. Heart disease can also severely compromise not only the length but also the quality of life. The development of CHD greatly increases the risk of heart attack, sudden death, and congestive heart failure. Unfortunately, up to a third of people who have their first heart attack die without prior warning. Although angioplasty and coronary artery bypass surgery have become routine procedures for helping to maintain blood flow to the heart muscle, preventing heart disease is and will always form the cornerstone for preventing death and disability from CHD.

Heart attacks occur from progressive injury to the walls of the coronary arteries, which are blood vessels that nourish the heart muscle. Coronary arterial injury begins at an early age. Many young men killed in the Korean and Vietnamese conflicts already had evidence of coronary disease at the age of 18 or 19 years. It is common for people to have heart attacks by the age of 35 or 40 years, especially if they have 1 or more risk factors for the development of CHD. Consequently, it stands to reason that if physicians intervene early and aggressively, they may be able to retard or even prevent the development and progression of CHD. Studies have proven this to be true.

Over the course of the last 5 decades, great progress has been made in identifying many of the most important factors that predispose people to the development of CHD. These "risk factors" include elevated blood cholesterol, elevated blood pressure (hypertension), diabetes, cigarette smoking, depression and social stress, obesity, and a family history of CHD. These risk factors, either alone or in combination, impart progressive injury to blood vessel walls. The injured portion of the blood vessel develops foci of fatty buildup known as atheromatous plaque. These plaques grow in size and lead to obstructions or blockages along the lumen of the coronary vessel. As the severity of the obstruction increases, less blood can flow through to the heart muscle. This leads to an oxygen deficit within the heart muscle that can manifest itself as chest pain, pressure, or tightness (angina pectoris). A heart attack occurs when an atheromatous plaque suddenly ruptures. The ruptured plaque becomes covered with clotted blood, and this leads to sudden cessation of blood flow to the heart muscle. If the obstruction is not rapidly relieved by emergency angioplasty or a clot buster, the affected portion of heart muscle dies. If the affected area of heart muscle is large enough, this can result in sudden death. If the patient survives, a heart attack can leave him or her disabled because of inability to tolerate physical exertion or even execute the routine activities of daily living. Controlling the severity of CHD risk factors is critical to the prevention of heart disease and heart attack.

What is cholesterol?

Based on studies performed around the world in both men and women and in every racial and ethnic group yet evaluated, increased blood cholesterol levels are unequivocally associated with increased risk for CHD. Our body tissues naturally produce cholesterol. The liver and brain are particularly capable of synthesizing cholesterol. We also derive cholesterol from many of the foods that we eat. For some people, simple lifestyle modification measures, such as a low-fat diet and increased exercise, are enough to reduce circulating blood levels of cholesterol. Many other people require a combination of medication and lifestyle modification to reduce their blood levels of cholesterol. The National Cholesterol Education Program has clearly defined cholesterol goals for people of varying levels of risk for CHD. The higher the risk for CHD, the lower the level of desirable cholesterol.

There are 3 forms of cholesterol, forms that can be labeled conveniently as "the good," "the bad,"and "the ugly." The good cholesterol is HDL or "high-density lipoprotein." HDL is beneficial because it helps to mop up blood vessel walls. It removes excess cholesterol from arterial walls and delivers it back to the liver for intestinal disposal. The higher your level of HDL, the lower your risk for developing CHD. A desirable level of HDL in men is 40 or more, while for women it is 50 or more.When HDL falls below these thresholds, lifestyle modification and/or medication is warranted to reduce risk for CHD. Aerobic exercise, moderate alcohol ingestion (2–8 oz of wine per day), smoking cessation, weight loss, and reduced carbohydrate ingestion all help to raise HDL. A Mediterranean diet rich in fruits, vegetables, whole grains, olive oil, and legumes is associated with increased HDL. Statins (Crestor, Zocor, and Lipitor), fibrates (Tricor and Lopid), and niacin can all raise HDL effectively. The benefits of these medications far outweigh their risks. If you have diabetes, thiazolidinediones (the TZD drugs), such as Avandia and Actos, can also be used to raise HDL. The use of any of these medications depends upon a variety of factors that your physician must sort out. Therapy is always individualized to the needs of individual patients. An HDL level cannot be too high. When it comes to HDL, the higher the better. For every 1 mg/dL elevation in HDL, risk for CHD decreases by approximately 3%.

The bad cholesterol is LDL, or "low-density lipoprotein." Generally speaking, when it comes to LDL, the lower the better. A variety of drugs can be used to decrease blood levels of LDL. By blocking cholesterol absorption from the gastrointestinal tract, LDL levels can be lowered. Such medications include Welchol and Zetia. The best drugs for decreasing LDL are the statins. Many studies conducted throughout the world in men and women have shown that the reduction of LDL with statins is associated with substantial reductions in risk for heart attack, stroke, sudden death, angina, and heart failure. The evidence supporting the use of statins in patients with high LDL is unequivocal. LDL is the type of cholesterol that builds up in blood vessel walls. It is toxic to blood vessels and compromises their normal function. As LDL builds up, obstructions to the flow of blood develop, ultimately leading to blockages, episodic chest pain, and heart attack. LDL is public enemy number 1.

The ugly cholesterol is Lp(a), or lipoprotein(a). Lp(a) is particularly toxic to blood vessels. Many people are simply genetically programmed to have high Lp(a). People are not routinely screened for the ugly cholesterol. If you have your cholesterol checked, make sure the panel includes a test for Lp(a). If it is high, it is particularly important to drive down your LDL. To date, no medications specifically reduce Lp(a) effectively. If Lp(a) is a problem, your physician should try to reduce your LDL to less than 80 in an effort to compensate for the elevation in the ugly cholesterol.

Triglycerides or blood fats are also important. Interestingly, high triglycerides appear to be an even more important risk factor in women than in men. Triglycerides should be kept to less than 150. Decreasing the intake of fat and increasing frequency of exercise can reduce high triglycerides. Fish oils enriched with omega-3 fatty acids can be particularly effective at reducing blood triglyceride levels and are a type of health food alternative to other medications. Omecor is an enriched form of omega-3 fish oils and is available by prescription. The fibrates, statins, and niacin can also reduce blood levels of triglycerides. In some cases, Xenical therapy may be warranted. Some people lack the molecular machinery to break down triglycerides in their blood with efficiency. Xenical blocks the absorption of fat from the diet and can lead to substantial reductions in blood triglyceride levels. One potential side effect of Xenical is the passage of oily stools that can be accompanied by urgency. If your triglycerides have been normal and you suddenly begin to experience a steady rise in their levels, you should be evaluated for possible new-onset diabetes or thyroid disease. Maintaining blood fats and the various forms of cholesterol in the normal range is critical to the prevention of CHD.

What is blood pressure?

Elevated blood pressure is an important source of chronic, recurrent injury to blood vessel walls. High blood pressure has also been shown to strongly predispose both men and women to CHD. Once blood pressure begins to creep above 120/80 mmHg, risk escalates continuously. Blood pressure that exceeds 140/90 mmHg warrants intervention with medication. Blood pressure should be reduced to 130/80 mmHg or less under optimal conditions. If you have diabetes and kidney disease, your blood pressure should be less than 125/75 mmHg. Lifestyle modification with weight loss, exercise, and salt restriction is an important means by which to control elevated blood pressure or hypertension. If you have hypertension, it is also important to avoid drugs that can raise blood pressure, such as the pseudoephedrine in over-the-counter decongestants.


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