What is angina?
Angina is short for “angina pectoris,” which in Latin means “pain of the chest.” More specifically, angina is pain originating from the heart when it doesn’t get enough blood flow.
How does angina occur? What causes it?
At different times, the heart has a varying need for blood flow and the oxygen it carries. The heart receives this blood flow through its own set of blood vessels called the coronary arteries. Normal coronary arteries can open up and the heart can pump itself more blood during times of increased need. Unfortunately, over time, these arteries can develop internal blockages that slow the flow of blood through them. When these blockages reach a certain degree – usually when the internal size of the artery is narrowed by about 70% or more – it becomes impossible for the heart to get enough blood during the times it needs more. These times of increased need include:
- During exercise
- When performing physical work
- After eating
- When experiencing emotional stress or a sudden increase in blood pressure
With the relatively decreased blood flow and oxygen, the heart muscle produces chemicals that cause the pain and other symptoms of angina. Stopping the exertion or work and placing nitroglycerine under the tongue helps restore the blood flow balance – symptoms are usually resolved in 5-10 minutes.
How and why do these blockages in the coronary arteries develop?
The coronary arteries start off, as do all arteries, with a smooth inner lining. Over time, material becomes imbedded in plaques, or deposits, under the inner lining. This process is called atherosclerosis, when it occurs in the coronary arteries it is called coronary artery disease (CAD) Plaques are a mixture of cholesterol, fatty acids, and scar tissue. Ongoing inflammation seems to be an active part of the process. Though CAD seems to be part of the natural aging process of the arteries, it develops at widely differing rates in different individuals, based on a variety of factors:
- High blood pressure
- Abnormal blood cholesterol levels (high LDL cholesterol and/or low HDL cholesterol)
- Male gender
- Eating increasing amounts of saturated fat and cholesterol (whether the blood cholesterol levels are abnormal or not)
- Being overweight
- Sedentary lifestyle
- Cocaine use
- High levels of certain chemicals in the blood, like homocysteine