Angina Pectoris is a phrase that comes from Latin and translates as 'tight chest'. Angina pectoris, commonly known as angina, is chest pain due to ischemia i.e. a lack of blood and oxygen supply of the heart muscle. It occurs when the heart muscle (myocardium) doesn't get as much blood and as much oxygen as it needs. This usually happens because one or more of the heart's arteries is narrowed or blocked.  Insufficient blood supply is called ischemia. It usually lasts for only a few minutes, and an attack is usually quickly relieved by rest or drugs. Also, it is possible to have myocardial ischemia without experiencing angina. Pain starts in the centre of the chest behind the breast bone or on the left side of the front of the chest. It can spread out to other parts of your body like your arms and stomach.

An episode of angina is not a heart attack. Having angina means you have an increased risk of having a heart attack. Time is very important in angina. The more time your heart is deprived of adequate blood flow, and thus oxygen, the more your heart muscle is at risk of heart attack or heart rhythm abnormalities. The longer you have chest pain from angina, the more your heart muscle is at risk of dying or malfunctioning.

Some people experience angina while sleeping or at rest. This type of angina may be caused by a spasm in a coronary artery, which most commonly occurs at the site of atherosclerotic plaque in a diseased vessel. Angina can be confused with a heart attack. However, unlike a heart attack, the pain from angina usually goes away in 15 minutes or less with rest.

Angina Pectoris differs from other types of Angina
Angina pectoris is totally different from Angina Tonsillaris and Ludwig's Angina.

1. Angina Pectoris refers to a constricting pain in the chest region.
2. Angina Tonsillaris refers to pain in the tonsils (located near the throat), and is a symptom of tonsillitis.
3. Ludwig's Angina, also called Angina Ludovici, is an infection of the tissues on the floor of the mouth and is also a serious disease.

There are three main types of Angina:
Angina can be classified into three types: Chronic exertional (Stable, Typical), Variant Angina (Prinzmetal's), or Unstable Angina (Crescendo Angina).

1. Stable Angina is characterized by predictable patterns of symptoms and periods of discomfort that occur during exercise or periods of stress. This pain is usually relieved with rest and/or treatment with nitroglycerin or another appropriate medication.
2. Unstable Angina is characterized by a change in the pattern of angina episodes, occurring more frequently, at rest, and/or not responding to treatment. It is usually a sign that the patient's condition is worsening.
3. Variant Angina almost always occurs during periods of rest, usually at night or early morning. The cause is a spasm of a coronary artery. It lasts for longer than other forms of angina and may subside with some physical activity.

Causes of Angina Pectoris
The two main causes of angina are coronary artery spasm, and atherosclerotic plaque buildup which causes critical blockage of the coronary artery. In most cases, the cause of angina is coronary atherosclerosis: the thickening of arteries that supply blood, oxygen and nutrients to the heart. In severe cases this can also happen when the heart is at rest.

Angina can be aggravated by other illnesses, including:

• A sustained fast heartbeat
• Anaemia
• Heart valve diseases such as severe Aortic Stenosis
• Hypertrophy or Thickening of the heart muscle

The exact cause(s) of coronary artery disease remains unknown. Yet experts have identified some of the risk factors that increase a person's chance of getting this disease. They include:

• Aging
• High blood pressure (hypertension)
• Cigarette smoking
• High blood cholesterol
• Being overweight
• Lack of exercise
• Family history of angina or heart attack at a young age
• Diabetes

Certain individuals, though, develop angina without having any of the above common risk factors for CAD.

Signs & Symptoms of Angina Pectoris
Symptoms typically start during physical exertion or emotional stress. They are often worse in cold or windy weather and sometimes after big meals.

• Anxiety
• Apprehension
• Breathlessness
• Crushing, tight, gripping type chest pain
• Discomfort can radiate into arms, jaw, teeth, ears, stomach and in rare cases between the shoulder blades.
• Dizziness
• Fainting
• Feeling of impending doom
• Heavy pressing sensation on the chest.
• Increased heart rate
• Increased shortness of breath on exercise.
• Light-headedness
• Numbness in the arm, shoulder, elbow or hand, normally on the left side.
• Pain begins while patient is at rest
• Pain in central chest or behind sternum
• Pain radiating down left arm, to jaw, neck or shoulder with or without associated chest pain
• Pallor (pale skin)
• Palpitations
• Squeezing sensation in the throat.
• Sweating

In some cases the fatty deposits that restrict blood flow can rupture. Blood then clots around the rupture, and the clot may be large enough to block the artery and seal off the blood supply. This may cause unstable angina or a heart attack.

Some patients have atypical angina (e.g., bloating, gas, abdominal distress) often ascribing symptoms to indigestion; belching may even seem to relieve the symptoms. Others have dyspnea due to the sharp, reversible increase in LV filling pressure that often accompanies ischemia. Frequently, the patient's description is imprecise, and whether the problem is angina, dyspnea, or both may be difficult to determine. Because ischemic symptoms require a minute or more to resolve, brief, fleeting sensations rarely represent angina.

Diagnosis of Angina Pectoris
Angina pectoris is diagnosed in a client by a physician performing a physical exam, reviewing his or her medical history and running the following tests on the client:

• Angiography: Angiography is a procedure in which a contrast medium is injected into the peripheral arteries.
• Electrocardiogram (ECG/ EKG): Electrocardiogram (ECG or EKG) is a test that checks the myocardium's functioning by measuring the electrical activity of the myocardium.
• Echocardiogram: Using ultrahigh-frequency sound waves the shape, size and motion of the myocardium's structures are examined.
• Exercise electrocardiogram (Stress test): This test is prescribed to help identify the cause of the unexplained chest pain, especially if CAD is suspected to be the cause.
• Thallium scan: This test is also known as cold spot imaging; with this test, the myocardial blood flow is evaluated as well as the myocardial cell status.
• Transesophageal echocardiogram (TEE): This test may be performing to evaluate more closely at the myocardium's whether the myocardium is producing blood clots.

Treatment of Angina Pectoris
The first step in angina treatment is to eliminate risk factors that are likely to hasten the progression of heart disease. This means that people with angina should stop smoking, lose excess weight, eat a heart-healthy diet, and exercise regularly, if possible.

• Drugs: In most instances, drugs are recommended for the treatment of angina before surgery is considered. A variety of medicines now are available for the treatment of angina. There are five main types of medication, which help to control symptoms and increase blood flow to the heart muscle:

  --Aspirin
  --Nitrates
  --Beta-blockers
  --Calcium channel blockers
  --Statin drugs

• Percutaneous Intervention (PCI): PCI (e.g., angioplasty, stenting) should be considered if angina persists despite drug therapy and worsens quality of life or if anatomic lesions (noted during angiography) put a patient at high risk of mortality.
• Surgery: Some people with angina have extensive narrowing of the heart's blood vessels. If atheromas (plaques; fatty deposits within an artery) block an individual's coronary arteries by more than 70%, the physician usually will recommend surgery to improve blood flow to the heart muscle. Surgical procedures relieve angina symptoms and also help to prevent heart attack. The two main surgeries for angina are:

1. Angioplasty: Angioplasty may be performed during cardiac catheterization to compress fatty deposits and relieve occlusion in patients with no calcification and partial occlusion. A certain risk is associated with this procedure, but its morbidity is lower than that for surgery.
2. Coronary artery bypass: A surgical technique available as an alternative to traditional CABG surgery is minimally invasive coronary artery bypass surgery, also known as keyhole surgery. This procedure requires a shorter recovery period and has fewer postoperative complications. Instead of sawing open the patient's sternum and spreading the ribs apart, several small cuts are made in the torso through which small surgical instruments and fiber-optic cameras are inserted.