In heart disease, what's a clot and what's a clog?

Coronary Clogs: Slow Strangulation

A coronary artery with atherosclerosis, indicated by the yellow mound on the bottom wall of the blood vessel
A coronary artery with atherosclerosis, indicated by the yellow mound on the bottom wall of the blood vessel
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Unfortunately, clogs aren't just wooden shoes worn by Dutch school children. The word also refers to the buildup of plaque inside your coronary arteries, the main pipelines that deliver oxygen-rich blood to your body.

Your arteries have three layers: a protective outer casing (the adventitia), a muscular middle layer (the media) and a thin, smooth inner layer (the intima), which allows blood to slide through to its destination. Like a finished wall in your home, this smooth inner layer suffers wear and tear. With a constant blast of blood pushing through these arteries, the inside lining is banged up from things like nicotine, natural minerals such as calcium and low-density lipoprotein (or LDL) cholesterol. High blood pressure also increases the force exerted against the arteries' inside lining, scuffing it up.

All these nicks, dings and chips may leave the middle arterial layer vulnerable to damage by exposing it to the bloodstream. To avoid that scenario, your body has several mechanisms for patching up these nicks, one of which is filling them with a spackle consisting of platelets, white blood cells and cholesterol.

It's not­ a perfect process, though. The infection-fighting white blood cells mean well, but they track toxic materials into the work zone, so the inner lining becomes more irritated, and the hole starts spreading. As this happens, more plaster is being used to fill the hole, more impurities are latching on, more white blood cells show up and the cycle continues, leading to bigger blockages. These blockages that harden the arteries are better known as clogs. In addition, the artery narrows, leading to even higher blood pressure as your heart tries to force blood past the coronary clogs.

As your arteries clog over many years, they stop being soft and supple and instead stiffen like an old garden hose that's been left too long in the sun. This worsening buildup of plaque and consequent hardening of the arteries is known as atherosclerosis, and it can limit the amount of blood reaching your heart. If your heart can't get the blood it needs, you may start feeling a chest pain called angina. This slow starving of the heart also drains you of energy and, not surprisingly, affects your quality of life.

By exercising and eating right, you can increase the amount of high-density lipoprotein (HDL) cholesterol in your body. HDL cholesterol is considered good because it can remove some of the plaque in the form of LDL, or bad, cholesterol from your clogged arteries. (To learn more about the different types of cholesterol, read What's the difference between LDL and HDL cholesterol?) Exercise also helps to lower blood pressure, which will relieve some of the burden on your troubled arteries. However, statin medications or more serious surgical measures, such as angioplasty, bypass surgery or stenting, may be needed to fix or bypass these clogs, .

As bad as coronary clogs are, they just lay the groundwork for something that can be even more dangerous: clots.