Types of Angina: Stable and Unstable

Angina pectoris is an acute chest discomfort or pain caused by the lack of blood supply to a particular part of the heart. Angina is not a disease; it’s a sign of an underlying cardiovascular problem. Researchers believe that about 7 million Americans suffer from angina pectoris. There are several types of angina – stable, variant, unstable, and microvascular angina.

Causes of Angina
In most cases, angina is the symptom of coronary heart disease associated with atherosclerosis of the coronary artery. Sometimes chest pain can be observed in other conditions (congenital or acquired valvular defects, myocarditis and inflammation of the coronary arteries) or it can be provoked by a spasm in the coronary arteries.

The mechanism of atherosclerosis-associated angina
Atherosclerotic plaque gradually narrows the lumen of the artery and causes the shortage of blood supply to the myocardium during significant physical and/or emotional overstrain. Severe atherosclerosis that narrows the lumen by 75% or more can cause such shortage even during moderate stress. In some cases, angina pectoris can be provoked by arterial hypotension, which is manifested by reduced blood flow to the coronary arteries.

Episodes of acute chest pain develop when oxygen needs of the cardiac muscle are not met by the blood flow. Angina attacks occur during physical activity, emotional stress, severe hypothermia or overheating of the body, after eating too fatty or spicy food or alcohol consumption. In all these cases the heart works harder, so the lack of oxygen becomes more evident and that causes pain.

Symptoms of Angina
Anginal pain is usually more intensive, it may feel like squeezing or pressure in the chest. Pain and discomfort can spread to the neck, shoulders, back, arms or jaw; sometimes it may even feel like indigestion. Angina attacks can last from 1 to 10 minutes and can be quickly stopped by taking specific medications or by ceasing physical activity. However, in certain patients an episode of angina can last from 30 seconds to 30 minutes.

Stable and unstable angina
These types of angina have quite a few differences and understanding them is important for realizing how dangerous this symptom may be to the health.

Stable angina pectoris occurs:
• In a pattern. It includes how often the attacks occur, how severe they are and what triggers them.
• When the heart works harder than usual. Exercising, eating a large meal, doing yard work, experiencing severe stress, etc. are believed to be its triggers.
• For short time periods. The pain goes away after a short rest or after using angina medications.

Unstable angina pectoris occurs:
• In no specific pattern. It’s unpredictable; the attacks are more severe and happen more often than episodes of stable angina.
• At random. It can happen at any time, even at rest, with or without physical activity.
• For longer periods of time. Rest doesn’t always relieve pain, the attack lasts for more than 20 minutes and requires emergency treatment because unstable angina can be an indication of an approaching heart attack.

The risk factors for both angina types are pretty much the same – diabetes, lack of exercise, obesity, high blood pressure, smoking, high cholesterol, male sex, family history of coronary artery disease before the age of 50.