Lipoproteins are molecules made of proteins and fat. They carry cholesterol and similar substances through the blood.
A blood test can be done to measure a specific type of lipoprotein called lipoprotein-a, or Lp(a). Lp(a) is considered a risk factor for heart disease.
How the test is performed:
Blood is typically drawn from a vein, usually from the inside of the elbow or the back of the hand. The site is cleaned with germ-killing medicine (antiseptic). The health care provider wraps an elastic band around the upper arm to apply pressure to the area and make the vein swell with blood.
Next, the health care provider gently inserts a needle into the vein. The blood collects into an airtight vial or tube attached to the needle. The elastic band is removed from your arm.
Once the blood has been collected, the needle is removed, and the puncture site is covered to stop any bleeding.
How to prepare for the test:
You will be asked not to eat anything for 12 hours before the test.
Do not smoke before the test.
How the test will feel:
A needle is inserted to draw blood. You may feel moderate pain, or only a prick or stinging sensation. Afterward, there may be some throbbing.
Why the test is performed:
High levels of lipoproteins can increase the risk of heart disease. The test is done to check your risk of atherosclerosis , stroke, and heart attack.
Normal values are below 30 mg/dL (milligrams per deciliter).
Note: Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.
What abnormal results mean:
Higher than normal values of Lp(a) are associated with a high risk for atherosclerosis, stroke, and heart attack.
What the risks are:
Veins and arteries vary in size from one patient to another and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult than from others.
Other risks associated with having blood drawn are slight but may include:
- Excessive bleeding
- Fainting or feeling light-headed
- Hematoma (blood accumulating under the skin)
- Infection (a slight risk any time the skin is broken)
Pagana TJ. Mosby’s Manual of Diagnostic and Laboratory Tests. 2nd ed. St. Louis, Mo: Mosby; 2002:106-110.