Coronary artery disease (CAD)

Over view of cardiovascular system and CAD

The cardiovascular system refers to the heart, blood vessels and the blood. Blood
contains oxygen and other nutrients which your body needs to survive. The body takes
these essential nutrients from the blood. At the same time, the body dumps waste
products like carbon dioxide, back into the blood, so they can be removed. The main
function of the cardiovascular system is therefore to maintain blood flow to all parts of
the body, to allow it to survive. The one-way system carries blood to all parts of your
body. This process of blood flow within your body is called circulation. Arteries carry oxygen-rich blood away from your heart, and veins carry oxygen-poor blood back to the heart.
The pumping action of the heart usually maintains a balance between cardiac output
and venous return. cardiac output is the amount of blood pumped out by each ventricle
In one minute. The normal adult blood volume is 5 liters.

What is coronary artery disease?
Coronary artery disease (CAD) is the most common type of heart disease in the United
States. It is sometimes called coronary heart disease or ischemic heart disease.
For some people, the first sign of CAD is a heart attack. You and your health care team
may be able to help reduce your risk for CAD.
CAD is caused by plaque buildup in the walls of the arteries that supply blood to the
heart (called coronary arteries) and other parts of the body. Plaque is made up of deposits of cholesterol and other substances in the artery. Plaque buildup causes the inside of the arteries to narrow over time, which can partially or totally block the blood flow. This process is called atherosclerosis.

Pathology

Coronary heart disease, also called coronary artery disease or ischemic heart disease,disease characterized by an inadequate supply of oxygen-rich blood to the heart muscle(myocardium) because of narrowing or blocking of a coronary artery by fatty plaques (see atherosclerosis). If the oxygen depletion is extreme, the effect may be a myocardial infarction (heart attack). If the deprivation is insufficient to cause infarction (death of a section of heart muscle), the effect may be angina pectoris (pain or discomfort in the chest). Both conditions can be fatal because they can lead to heart failure or ventricular fibrillation. The latter, characterized by an uncontrolled and uncoordinated contraction of the ventricles (the lower chambers of the heart), can induce sudden death.

A variety of risk factors have been associated with coronary heart disease; examples include high blood pressure, elevated blood cholesterol levels, smoking, obesity,diabetes, unhealthy diet, and family history of early coronary heart disease (i.e.,
diagnosed in middle age). Individuals with hereditary conditions such as familial hypercholesterolemia (a disorder in which the body’s tissues are incapable of removing cholesterol from the bloodstream) also are at increased risk.
Coronary artery bypass surgery (also known as coronary artery bypass grafting) or
angioplasty may be necessary if medications and diet and lifestyle changes, such as
frequent exercise and cessation of smoking, are not effective.

Coronary Artery Disease Signs & Symptoms

One common symptom of CAD is a type of chest pain called Angina. Angina may feel like tightness, heaviness, or pressure in your chest. It may involve an aching, burning, or numb sensation. It can also feel like fullness or squeezing. You may also feel angina radiating to your back, jaw, neck, shoulders, or arms. The discomfort may also extend from your shoulder down to your fingers or into your upper abdomen. You typically won’t feel angina pain above your ears or below your belly button. Sometimes angina causes only a vague feeling of pressure, heaviness, or discomfort. It can masquerade as indigestion or shortness of breath. Women and older adults are more likely than men and younger people to have this kind of angina. Angina can cause other symptoms too,such as sweating or a general sense that something is wrong. One of the challenges
with CAD is that it doesn’t always have clear signs or symptoms in the early stages, and symptoms may only show up when patients develop a complication. “For some people, the first sign of CAD is a heart attack,” the CDC reports.
In addition to angina, CAD may cause the following symptoms:

• Shortness of breath.
• Management & Prevention
• Sweating.
• Weakness.
• Dizziness.
• Nausea.
• Rapid heartbeat
• Palpitations — the feeling that your heart is pounding hard and rapidly and is fluttering or skipping beats.

Management & Prevention

Because CAD is not a sudden-onset condition, but rather takes years to develop, there are several ways you can reduce your risk of developing the disease. The same lifestyle habits that can help treat coronary artery disease can also help prevent it from developing in the first place. Leading a healthy lifestyle can help keep your arteries strong and clear of plaque. To improve your heart health, you can

• Quit smoking.
• Make changes in your diet to reduce your cholesterol.
• Control your blood pressure.
• Manage blood sugar if you have diabetes.
• Low-fat, low-sodium and low-cholesterol foods are recommended. A registered
  dietitian can help you make the right dietary changes.
• Increase your exercise/activity level to help achieve and maintain a healthy weight
  and reduce stress. But, check with your doctor before starting an exercise program. Ask your doctor about participating in a cardiac rehabilitation program

Diagnosing CAD
Diagnosing CAD requires a review of your medical history, a physical examination, and other medical testing. These tests include:

• Electrocardiogram: This test monitors electrical signals that travel through your
  heart. It may help your doctor determine whether you’ve had a heart attack.
• Echocardiogram: This imaging test uses ultrasound waves to create a picture of
  your heart. The results of this test reveal whether certain things in your heart are
  functioning properly.
• Stress test: This particular test measures the stress on your heart during physical activity and while at rest. The test monitors your heart’s electrical activity while you walk on a treadmill or ride a stationary bike.
• Cardiac catheterization (left heart catheterization): During this procedure, your
  doctor injects a special dye into your coronary arteries through a catheter inserted through an artery in your groin or forearm. The dye helps enhance the
  radiographic image of your coronary arteries to identify any blockages.
• Heart CT scan: Your doctor may use this imaging test to check for calcium
  deposits in your arteries.

Treatment
Before anything you should change your lifestyle, and if it’s still not effective, the doctor prescribes you medications.
Medication Therapy :

• Cholesterol-modifying medications. By decreasing the amount of cholesterol in
  the blood, especially (LDL, or the “bad”) cholesterol, these drugs decrease the primary material that deposits on the coronary arteries.
• Aspirin. blood thinner. This can reduce the tendency of your blood to clot, which may help prevent obstruction of your coronary arteries.
• Beta-blockers: reduce blood pressure and heart rate.
• Nitroglycerin sprays, or tablets: These widen the arteries and reduce the heart’s
  demand for blood, as well as soothe chest pain.
• Calcium channel blockers: These will widen the coronary arteries, improving
  blood flow to the heart and reducing hypertension.
• Ranolazine. This medication may help people with chest pain (angina). It may be
  prescribed with a beta blocker or instead of a beta blocker if you can’t take it.

If your condition doesn’t improve with lifestyle changes and medication, your doctor may recommend a procedure to increase blood flow to your heart. These procedures may be:

• balloon angioplasty: to widen blocked arteries and smoosh down the plaque
  buildup, usually performed with insertion of a stent to help keep the lumen open after the procedure.
• coronary artery bypass graft surgery: to restore blood flow to the heart in open chest surgery.
• enhanced external counter pulsation: to stimulate the formation of new small blood vessels to naturally bypass clogged arteries in a noninvasive procedure.