What You Need To Know About Atherosclerosis

What is Atherosclerosis?

Atherosclerosis, also known as “hardening of the arteries”, occurs when focal areas of the artery wall thicken in response to risk factors that such as high LDL particle levels, smoking or high blood pressure.

Over time, areas of thickening may grow into a larger area of arterial wall disease called a “plaque". If a plaque becomes unstable and suddenly ruptures, a series of events occur that result in a sudden loss of blood flow in the affected artery. Unless blood flow is quickly restored, regions of the heart or brain will die resulting in heart attacks and stroke, respectively. Unfortunately, these clinical events (heart attack and stroke) are often the first sign that someone has atherosclerosis.

Can atherosclerosis be detected before clinical events occur?

Yes, but specialized technology is required.

Non-invasive imaging technologies can identify atherosclerosis at multiple stages of development. The most sensitive technique for finding the earliest stages of atherosclerosis is high resolution ultrasound imaging of the carotid arteries termed carotid intima-media thickness, or "CIMT". Using this technology arterial wall images are generated showing anatomic details down to 0.001 mm. From images acquired at multiple locations, details regarding the thickness of the arterial wall, as well as the presence and magnitude of carotid plaques, can be reported.

CIMT testing requires substantial training and expertise in image acquisition, as well as image interpretation. This has made high quality CIMT testing limited in many locations. Specific protocols have been developed by the American Society of Echocardiography that should be used by those providing CIMT information in clinical practice.

More advanced atherosclerosis is detected by measuring calcium deposited in growing plaques by a CT scan technique called Coronary Calcium Score. This technology is much simpler, but detects disease at a much later state of development. For this reason coronary calcium scoring is not recommended in men less than 45 years of age or females less than 55 years of age.

Can atherosclerosis be halted or reversed?

Yes it can.

Although it takes decades for the process to develop, recent trials show that early atherosclerosis is treatable. Several therapies that affect levels of circulating lipoproteins, particles that carry cholesterol in the bloodstream, can actually stop or reverse atherosclerosis. In research centers CIMT measurements can be followed every 2 - 3 years to evaluate the response to therapy. This approach holds promise that in the future this technology will be able to judge, at an individual level, if lipoprotein therapies have been successful in halting or reversing atherosclerosis.

Comments

[steve]

Dr Cromwell: I recently came across this blog via Dr. Peter Attia's blog and have a question: In a patient with CAD, normal weight, exercises, no thyroid or blood pressure or glucose issues, how low do particle levels of LDL need to be to gain some level of reversal, or at least to stop progression of CAD?
Thanks, you do a great service with the info you provide.

[William Cromwell, MD]

Steve:

From your description the individual is relatively low risk and should not have increased atherosclerosis at their age. If that is true the LDL-P goal should be less than 1300.

However, if, despite relatively low risk per traditional risk factors, the individual has elevated atherosclerosis for age then LDL-P less than 1000 would be a minimal target of therapy.