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Can high cholesterol lead to a heart attack?

Eventually, plaque buildup that is not treated properly may completely block an artery. This can occur either because the plaque itself becomes so thick or because it leads to a blood clot, called a thrombus.

As plaque deposits grow, they may crack or tear. When this happens, blood naturally begins to clot in the area. The blood can form a clot on the plaque's surface that's large enough to fully block the artery. If this happens in one of your heart's arteries, called the coronary arteries, it causes a heart attack. A heart attack is also called a myocardial infarction.

Because of tears in plaque and blood clots, a 30% blockage of your arteries can suddenly threaten your life. During a heart attack, the part of your heart that isn't getting oxygen begins to die. In some cases, the damage cannot be reversed.

What Else Might Happen to Me?

Blocked arteries in other areas of your body can cause serious health problems, too.

  • If an artery supplying your brain becomes too narrowed, you may have a stroke. A stroke is sometimes called a brain attack.
  • Sometimes little clots within the arteries supplying your brain can break off. This can result in mini-strokes, which are also called transient ischemic attacks, or TIAs.
  • Blocked arteries can also reduce blood flow to your arms or legs. This condition is called peripheral vascular disease. If the blood supply to your legs is partially blocked, you may feel leg pain that may limit your ability to get around. If there is no blood flow to one of your arms or legs, the tissue there may die. This is called gangrene. Often doctors must amputate a limb affected by gangrene.

The risk of these serious problems makes it very important for you to get tested for high cholesterol and to follow your treatment if you have high cholesterol.