1.20 The Basics of Heart Disease
Here we are going to talk about some basic concepts about heart disease, including the basic anatomy and physiology of the heart. How exactly does the heart work? What do we mean when we say heart disease? What is this #1 killer in the U.S. that the HeartStrong.com program is trying so hard to prevent? It is very important to have a basic understanding of heart disease right now as you start to get yourself heart healthy.
What is Heart Disease?
The phrase “heart disease” can actually refer to any problem with the heart including heart attack, heart failure, heart rhythm problems or other heart conditions. However, usually when we are talking about “heart disease”, we are referring to coronary artery disease (cholesterol and calcium plaque that clogs the coronary arteries and can lead to heart attack). This is what it looks like:
The normal artery (#1 above) has a lining of cells called the “endothelium” that protects the artery. Eventually, something damages the endothelium (such as eating unhealthy high cholesterol foods or smoking). This makes it susceptible to cholesterol depositing in the wall of the artery forming a “fatty streak (#3 above). This happens mostly from “oxidized LDL” cholesterol in the bloodstream. This process develops slowly over many years. Eventually, as more and more cholesterol builds up, a large cholesterol plaque can form, blocking the flow of blood to the heart muscle (#4 above). If the plaque becomes unstable, a blood clot can form on it within minutes and can sometimes completely block the flow of blood suddenly. This is what causes a “heart attack.”
We need to prevent this whole process from happening as best as we can, or at least stop it from getting worse. Many believe it can even be reversed with the proper diet and lifestyle changes. But first we need to learn a bit more about the basic structure and functioning of the heart, so lets get to it!