General Illness Information
Coronary Artery Disease
Medical Term: Ischemic Heart Disease
Description: Coronary artery disease is a conditionÂ in which fatty depositsÂ (atheroma) accumulate in the cells lining the wall of the coronary arteries. These fatty deposits build up gradually and irregularly in the large branches of the two main coronary arteries which encircle the heart and are the main source of its blood supply. This process is called atherosclerosis which leads toÂ narrowing or hardening of the blood vessels supplying blood to the heart muscle (the coronary arteries ).ThisÂ results in ischemia ( inability to provide adequate oxygen) to heart muscle and this can cause damage to the heart muscle . Complete occlusion of the blood vessel leads to a heart attack (myocardial infarction).
In the United States , cardiovascular disease is the leading cause of death among both sexes, and coronary artery disease is the commonest cause of cardiovascular disease. Myocardial infarction causes 35% of deaths in men between 35 and 50.The death rate is higher for men than for women between the ages of 35 and 55.However, after the age 55, the death rate for men declines but the rate for women continues to climb.
Exact cause is unknown. However there are a number of risk factors. Control of these risk factors has been shown to reduce the severity and complications of the disease.
Prevention: It is now clear that reducing certain risk factors, we can bothÂ preventÂ coronary artery disease andÂ delay its progression and complicationsÂ after it it has become manifest. Treatment of lipid abnormalities has now been shown to delay the progression of atherosclerosis and in some cases has even produced regression of the atherosclerotic plaques
Signs & Symptoms
Early stages: No symptoms.
Angina pectoris (burning, squeezing, heaviness, or tightness in the chest that may extend to the left arm, neck, jaw, or shoulder blade). See Angina Pectoris.
Typically, angina is precipitated by physical activity, lasting no more than a few minutes, and is relieved by rest. Usually angina is worse when exertion follows a meal. It is also worse in cold weather and can be triggered by walking from a warm room into the cold air. Emotional stress can also cause or worsen angina.
Not all people with ischemia will present with angina. Ischemia without angina is called silent ischemia. It is not yet understood why ischemia is sometimes silent.
- Family history of coronary artery disease, diabetes, high blood pressure or atherosclerosis;
- Poor nutrition, especially too much fat in the diet;
- Previous heart attack or stroke;
- Previous heart attack or stroke;
- Elevated cholesterol and/or low level of HDL (high-density lipoprotein);
- Type A personality
Diagnosis & Treatment
Diagnosis of angina is a clinical diagnosis based on a characteristic complaint of chest discomfort or chest pain brought on by exertion and relieved by rest. Confirmation may be obtained by observing reversible ischemic changes on ECG during an attack or by giving a test dose of sublingual nitroglycerin that characteristically relieves the pain in 1 to 3 minutes.
Certain tests may help determine the severity of ischemia and the presence and extent of the coronary artery disease. Diagnostic tests may include electrocardiogram (measures electrical activity of the heart), echocardiogram (measures sound waves), exercise-tolerance test, thallium stress test, blood studies to measure total fat, cholesterol and lipoproteins, X-rays of the chest and coronary angiogram (cardiac catheterization).
- Stop smoking;
- Treat elevated cholesterol levels with low fat, low cholesterol diet, exercise and cholesterol lowering medications;
- Treat elevated blood pressure;
- Reduce stress;
- Maintain ideal body weight;
- Balloon angioplasty (treatment for obstructed arteries, especially those supplying blood to the heart and brain. A small uninflated balloon is passed up the artery to the obstruction, and then expanded to release the obstruction;
- Although these procedures may decrease or eliminate symptoms for a while, they do not control the underlying disease;
- Surgery to bypass coronary arteries (severe cases);
- End-stage coronary artery disease, even when no simple procedures will help, can still be cured with a heart transplant in rare cases.
Four types of medications are available: beta-blockers, nitrates, calcium channel antagonists and anti-platelet drugs.
- Beta-blockers- reduce the resting heart rate and so reduce the demand for oxygen. Beta-blockers and nitrates have been proven to reduce the incidence of heart attacks and sudden deaths in people with coronary artery disease;
- Nitrates, such as nitroglycerin, cause dilatation of the blood vessels. There are short-acting and long-acting nitrates. Nitroglycerin is available as a tablet (sublingual) or an oral spray. A tablet of nitroglycerin placed under the tongue or inhalation of the oral spray usually relieves an episode of angina in 1 to 3 minutes, the effect of these short-acting nitrates lasts 30 minutes. Anyone with chronic stable angina must keep nitroglycerin tablets or spray with them at all times;
- Long-acting nitrates are available as tablets, skin patches or paste. Tablets are taken 1 to 4 times daily. Nitro paste and skin patches, in which the drug is absorbed through the skin over many hours, are also effective. Long-acting nitrates do tend to lose their effectiveness when taken regularly and therefore it is recommended to have 8 to 12 hour interval without taking the drug to maintain its effectiveness;
- Calcium channel antagonists – prevent the blood vessels from constricting and thus prevent coronary artery spasm. Certain calcium antagonists, such as verapamil and diltiazem, also slow the heart rate and in some patients these drugs are used in conjunction with beta-blockers to prevent episodes of tachycardia (fast heart rate);
- Anti-platelet drugs, such as aspirin is recommended for patients with coronary artery disease. Aspirin binds irreversibly to platelets and prevents them from clumping on blood vessel walls- thus preventing platelets from forming a clot on the fatty plaques which could block an artery and result in heart attack. Recommended dose is one baby aspirin or half an adult aspirin daily. For people with allergy to aspirin can be treated with alternative medications such as ticlopidine or clopidogrel bisulphate.
Engage in a program of moderate, daily physical exercise. Resume sexual activity once medical permission is given.
Low-fat and low cholesterol diet.
If you are overweight, begin a moderate reducing diet and stick to it.
- Angina pectoris;
- Life-threatening myocardial infarction (death of heart muscle cells from inadequate blood supply);
- Sudden death;
Treatment can prolong life and improve its quality.
Tremendous amount of research in this field, and new advances are being made and increasing evidence that aggressive treatment can reverse or arrest course of this disease. It is very important to follow your doctor’s instructions, especially with respect to lifestyle changes and cholesterol reduction.
Long term prognosis depends on a number of key factors such as the age, the extent of coronary artery disease, the severity of symptoms and most of all, the pumping ability of the heart.