Your Guide to the PLAC Test

Find out how the PLAC test works and whether you might benefit from getting one.

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Cholesterol buildup in blood vessels has long been known to lead to dangerous clotting and, in some cases, heart attack or stroke. Unfortunately, it’s not easy to know if and where these buildups of cholesterol are occurring. The amount of LDL cholesterol in the blood can give an indication, but it only gives a partial picture and many with high cholesterol will never develop heart disease. As a result, physicians try to combine cholesterol levels with other numbers, like how active you are or how much you smoke. Unfortunately, even those numbers can’t give a direct picture of what’s actually happening in a person’s blood vessels. This where the PLAC test comes in.

What causes heart attacks and strokes?

Heart disease and certain kinds of strokes occur when a clot blocks blood vessels. That blockage prevents oxygen from getting to tissues like heart muscle or brain cells that desperately need it. Without oxygen, those tissues eventually die and generally can’t be regenerated.

These clots don’t appear out of nowhere. They often happen in blood vessels that have built up cholesterol along their walls. When cholesterol deposits in the walls of a blood vessel, it irritates the surrounding tissues and attracts immune cells. These immune cells start to attack and break down the cholesterol while releasing inflammation signals. They encase the damaging cholesterol and its breakdown products with a tough shell of fibrous tissue to protect the body from what’s inside. This cholesterol capsule is called an atheroma.

Unfortunately, this case can break open, especially when the deposit gets too big. The cholesterol, immune cells and other chemicals are released into the bloodstream and trigger the blood to form a clot that can then block off the entire vessel.

What does the PLAC test measure?

Inside the atheroma is an enzyme called Lp-PLA2. Immune cells make this enzyme and helps convert LDL cholesterol into inflammatory compounds. Research has shown that the more of this enzyme is found in the blood, the more unstable and ready to burst someone’s atheroma is likely to be. This may be because an atheroma that’s unstable and starting to crack is already leaking what’s inside, which includes Lp-PLA2. The PLAC test measures the levels of this enzyme in the blood. The higher it is, the higher the concern that an individual is about to have a stroke or heart attack.

Why is the PLAC test helpful?

The test gives us a sense of whether someone might be at high risk in the near future. It’s a warning sign that tells medical providers to do whatever they can to lower someone’s cholesterol, blood pressure and clot risk. The test gives a snapshot that gives care providers a sense of how dangerous their patient’s situation really is.

Who needs a PLAC test?

The traditional methods of determining heart disease and stroke risk are still very good at identifying those who most need treatment. The PLAC test doesn’t refute or replace these measures and doesn’t change recommendations about heart-healthy behaviors like quitting smoking, increasing exercise, reducing alcohol consumption or eating less meat.

Instead, the PLAC test adds another angle your doctor can use if he or she suspects your picture might be worse than your risk profile is letting on. If, for example, you seem healthy but have several family members in similar health who have had heart attacks, your doctor may decide to do a PLAC test to make sure he or she isn’t missing something. In many cases, the picture of heart disease risk will be clear. The PLAC Test helps in those cases where the available information doesn’t tell the whole story.

Where can I get a PLAC test?

Your doctor will determine whether a PLAC test is necessary or appropriate. The PLAC test is only just being rolled out and may not be available in your medical facility.