In our first blog, using coronary calcification as an illustration, I showed arteriosclerosis (AS) is a dynamic, active, progressive disease process. AS, in many ways, is similar to tuberculosis. Shown here is a cross section of a coronary artery of a patient who died of heart disease containing a plaque that narrows the channel of the artery about 50%. I would not consider this to be serious narrowing. The red color is dye material I have injected into the artery to get it fully distended. The plaque is the white material to the right of the red color, showing the plaque affects only 1 side of the artery wall, leaving the other side unaffected. This is a typical plaque.
We call plaque growth the “proliferation” of tissue. Proliferation is the initial response or the first sign of arteriosclerosis. The reason plaques begin to grow is believed to be started by a small focal injury (unknown injurious agent) to an area of the artery wall. The body responds to this injury by growing scar tissue. We call this the “proliferative phase” of arteriosclerosis. It is easy to see that as the plaque continues to grow it could, in the fullness of time, completely obstruct the artery channel.
SUMMARY: AS is a chronic progressive disease, initiated by focal injury to the artery wall, followed by progressive growth and proliferation scar tissue. The proliferation of tissue should be viewed as a defensive response or an attempt to heal the injury. However this tissue is fatally flawed and in the fullness of time will undergo degeneration and destruction, resulting in an “Atheroma.”
To Be Continued.
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