Angina is not a disease but a symptom of coronary artery disease described by chest pain caused by reduced blood flow to the heart muscle. It is typically described as squeezing, pressure, heaviness, tightness or pain in your chest.
It is relatively common but can be hard to distinguish from other types of chest pain, such as the pain or discomfort of indigestion.
It occurs when cardiac workload and resultant myocardial oxygen demand exceed the ability of coronary arteries to supply an adequate amount of oxygenated blood, as can occur when the arteries are narrowed. Narrowing usually results from coronary artery atherosclerosis but may result from coronary artery spasm or, rarely, coronary artery embolism. Acute coronary thrombosis can cause angina if obstruction is partial or transient, but it usually causes acute Myocardial Infarction (MI).
Because myocardial oxygen demand is determined mainly by heart rate, systolic wall tension, and contractility, narrowing of a coronary artery typically results in angina that occurs during exertion and is relieved by rest.
In addition to exertion, cardiac workload can be increased by disorders such as hypertension, aortic stenosis, or hypertrophic cardiomyopathy. In such cases, angina can result whether atherosclerosis is present or not. These disorders can also decrease relative myocardial perfusion because myocardial mass is increased (causing decreased diastolic flow).
A decreased oxygen supply, as in severe anemia or hypoxia, can precipitate or aggravate angina.
In stable angina, episodes of chest discomfort are usually predictable. They can occur during exertion or during mental or emotional stress. Normally, the chest discomfort is relieved with rest, use of nitroglycerin, or both.
- Develops when your heart works harder, such as when you exercise or climb stairs
- Can usually be predicted and the pain is usually similar to previous types of chest pain you’ve had
- Lasts a short time, perhaps five minutes or less
- Disappears sooner if you rest or use your medication
In unstable angina, chest pain can occur at any time—often while a person is resting. The discomfort may be more severe and last longer than in typical chest pain. The most common cause is reduced blood flow to the heart muscle because the coronary arteries are narrowed by fatty buildups.
- Occurs even at rest
- Is a change in your usual pattern of chest pain
- Is unexpected
- Is usually more severe and lasts longer than stable angina, maybe as long as 30 minutes
- May not disappear with rest or use of medication
- Might signal a heart attack
Variant Angina Pectoris
Variant angina pectoris can happen at any time. It nearly always occurs when a person is resting. Attacks can be very painful and usually happen between midnight and 8 a.m. Variant chest pain is caused by spasms in the coronary arteries. About two-thirds of people with variant chest pain have severe coronary blockages in at least one major vessel. The spasm usually occurs very close to the blockage.
Micro vascular Chest Pain
This is a recently-discovered type of chest pain. Patients with this condition experience chest pain but have no apparent coronary artery blockage. Physicians have found that the pain results from poor function of tiny blood vessels nourishing the heart as well as the arms and legs. This can be treated with some of the same medications used for angina pectoris.
Symptoms of Angina Pectoris
- A pressing, squeezing, or crushing pain, usually in the chest under the breast bone
- Pain radiating in the arms, shoulders, jaw, neck, and back
- Shortness of breath
The chest pain associated with angina usually begins with physical exertion. Other triggers include emotional stress, extreme cold and heat, heavy meals, excessive alcohol consumption, and cigarette smoking.
Angina chest pain is usually relieved within a few minutes by resting or by taking prescribed cardiac medications.
The symptoms of angina pectoris may resemble other medical conditions or problems.
- High levels of cholesterol in the blood
- High blood pressure
- Male gender
- Sedentary lifestyle
- Family history of coronary heart disease
- Regular use of stimulants e.g. caffeine, nicotine, diet pills
The main goals of angina treatment are to
- Relieve acute symptoms
- Prevent or reduce ischemia
- Prevent future ischemic events
For an acute attack, sublingual nitroglycerin is the most effective drug.
To prevent ischemia, all patients diagnosed with coronary artery disease or at high risk of developing CAD should take an anti platelet drug daily. Beta-blockers, unless contraindicated or not tolerated, are given to most patients. For some patients, prevention of symptoms requires calcium channel blockers or long-acting nitrates.
Reversible risk factors are modified as much as possible ( Smokers should stop smoking).
Hypertension is treated diligently because even mild hypertension increases cardiac workload.
Weight loss alone often reduces the severity of angina.
Aggressive reduction of total cholesterol and low-density lipoprotein (LDL) cholesterol (via diet plus drugs as necessary) slows the progression of Coronary Artery Disease.
An exercise program emphasizing walking often improves the sense of well-being, reduces risk of acute ischemic events, and improves exercise tolerance.