Preventing and Reversing Heart Disease For Dummies. James M. Rippe

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      Current evidence suggests that stable plaques typically have thicker, more fibrous caps with few inflammatory cells and more calcification, which make the cap tougher. Stable plaques also appear to have fewer lipids within. Although stable plaques often are large, the edges or shoulders of the lesion usually are smooth and tapered.

      Unstable plaques, by contrast, are smaller in size but are very rich in cholesterol and incorporate many more inflammatory cells, which release chemicals that degrade the fibrous cap. Unstable plaques often appear structurally weak. In addition, the thinner cap may be easily ruptured or torn by a number of forces, ranging from the normal flow of blood at high stress points in the arterial system to sudden pressures such as suddenly increased blood pressure from exertion.

      Researchers continue to look for tests and techniques that accurately identify and assess unstable plaque. Such tools would enable physicians to better identify individuals at greater risk of acute events and begin preventive measures.

       Understanding a different type of coronary disease: Microvascular disease

      Some people who experience reduced flow of blood to the heart do not have narrowings of the larger coronary arteries caused by atherosclerotic plaque. Instead, they have coronary microvascular disease (MVD). MVD occurs much more often in women than men, particularly in premenopausal or younger women. In MVD, smaller blood vessels in the heart, which range from 100 micrometers (about the size of a human hair) to 200 micrometers constrict, preventing adequate oxygenated blood from reaching the heart muscle. As a result, people with MVD may have clear larger coronary arteries but still experience the symptoms of chest pain, although the discomfort is usually more diffuse and may last longer than with angina in CHD.

      The causes of MVD are not yet clear, but chronic inflammation appears to play an important role. And the risks factors for CHD, such as high blood pressure (particularly before menopause), unhealthy cholesterol levels, smoking, and diabetes appear to contribute. Current research is also looking for possible risk factors unique to MVD as well as for more effective diagnostic techniques.

      

If you have symptoms of heart disease (see the next section) but have clear coronary arteries, ask your physician about MVD, particularly if you are a woman.

       Knowing when chest pain is an emergency

      

People with coronary artery disease and angina typically live with this problem for many years and discover how to manage it effectively with appropriate medicines and advice from their physicians. When angina pain changes in character, however, it can signal unstable angina or even heart attack. If you experience any of the following characteristics of chest discomfort, you need to call 911 and be taken to a hospital immediately:

      ✔ Pain or discomfort that is worse than you have ever experienced before

      ✔ Pain or discomfort that is not relieved by three nitroglycerin tablets in succession, each taken five minutes apart

      ✔ Pain or discomfort that is accompanied by fainting or lightheadedness, nausea, and/or cool clammy skin

      ✔ Pain or discomfort lasting longer than 20 minutes

      If any of these symptoms occur, you need to call an ambulance and be taken immediately to a hospital. Under no circumstances should you drive yourself to the hospital.

       Recognizing the Symptoms and Manifestations of Coronary Heart Disease

      Because every person is an individual, physical responses to progressive coronary artery disease vary. Not every individual with heart disease has every manifestation and symptom of the condition. Individuals likewise experience specific symptoms in different ways. But these manifestations are typical:

      ✔ Nothing: Many people can have significant coronary atherosclerosis but experience no discomfort or other sign of the disease. That’s why this condition is known in medicine as silent ischemia. Ischemia means lack of blood flow. People with diabetes are particularly susceptible to silent ischemia, but others can have it, too.

      ✔ Angina: More formally known as angina pectoris, angina is typified by temporary chest pain, usually during exertion. This pain usually is felt as a tightness or uncomfortable feeling across the chest or up to the neck and jaw, not as a sharp stab. Angina also may have other manifestations.

      ✔

Unstable angina: Chest pain that is new, occurs when you’re at rest, or suddenly grows more severe is called unstable angina. It’s a medical emergency.

      ✔ Heart attack: Completely cutting off blood flow to a coronary artery causes an acute heart attack, or myocardial infarction (MI), the most severe result of coronary heart disease. The closure can be gradual or the result of a blood clot. A spasm in a coronary artery, particularly in the area of a narrowing, may also result in heart attack.

      ✔ Sudden death: The cause of sudden death from coronary heart disease often is a rhythm problem such as ventricular tachycardia or ventricular fibrillation. These rhythm problems sometimes occur in the setting of an acute heart attack. I’ve highlighted it here to make the point that the first indication or symptom for some people that they have CHD is a fatal cardiac arrest or heart attack. Many of these deaths happen to people in their 50s, 40s, or younger.

Recognizing angina, or chest pain

      Angina typically is a discomfort felt in the chest, often beneath the breastbone (or sternum) or in nearby areas such as the neck, jaw, back, or arms.