All causes of angina are conditions which narrow coronary arteries and reduce the amount of oxygen-rich blood flowing to the heart muscle. There are different reasons a person may have this problem, including coronary artery disease, physical exertion, extreme temperatures, and smoking. Other causes of angina are medicines that tighten or narrow arteries, severe anemia, spasms in coronary arteries, or if a blood clot forms or plaque in a blood vessel bursts and blocks or narrows an artery.
Angina is severe chest pain brought on by ischemia, or oxygen deprivation to the heart. Coronary artery disease is the most common cause of this. Plaque narrows coronary arteries and reduces the flow of blood. A patient who has coronary artery disease may not always get angina, but if when the person's heart rate and demand for oxygen in the blood is increased, it can trigger symptoms.
There are several different types of angina, including stable angina, unstable angina, microvascular angina, and variant angina. All cause less oxygen-rich blood to get to the heart, causing pain. The different types of angina are often caused by different conditions.
Stable angina generally comes from physical exertion. Exercising — sometimes even simply walking or climbing up a flight of stairs — requires the heart to have more oxygen-rich blood. This type of angina can also be caused by smoking, eating a heavy meal, or experiencing emotional stress.
If a blood clot forms or plaque in a blood vessel bursts and blocks or narrows an artery, it can lead to unstable angina. This happens suddenly and will severely decrease blood flow to the heart muscle. This pain is an important warning sign, and should be taken very seriously. A heart attack can occur in cases in which the artery is blocked entirely. Another cause of unstable angina includes severe anemia.
When the blood flow in the smaller coronary arteries is reduced, it can cause microvascular angina. In such cases, the blood flow reduction may be caused by plaque, spasms, or damage or disease. This type of angina may also be a symptom of another condition, called coronary microvascular disease.
Another of the causes of angina happens when a coronary artery spasms, or contracts suddenly. This is called variant angina. It causes the artery to narrow and the flow of blood to the heart is sharply reduced or even stopped. Besides heart diseases, certain medications, drugs like cocaine, stress, and cold temperatures can cause arteries to spasm. Variant angina is also called Prinzmetal's angina.
Many of the causes of angina can be mediated with medication and lifestyle changes. Factors such as high blood pressure, high cholesterol, and obesity put people at higher risk for angina and other conditions. Lowering the risk of coronary artery diseases by stopping smoking, increasing physical activity, and eating a healthier diet can also reduce a person's chances of developing angina.