Lipoprotein(a) concentration (measured by immunoassay)

What Is Lipoprotein(a)?

Lipoprotein(a) is a unique lipoprotein particle that combines cholesterol and a protein called apolipoprotein(a). While it shares some traits with LDL ('bad' cholesterol), it behaves differently in the body and may play a role in clogging arteries more aggressively than LDL alone. High levels are linked to higher risks of heart attacks and strokes, even in people without traditional risk factors like high blood pressure or diabetes.

Why Might You Need This Test?

Your doctor may order this test if you have a strong family history of heart disease, early-onset heart problems, or other conditions like aortic stenosis. It’s also sometimes checked in people with high LDL cholesterol or those who’ve already had a heart event to assess residual risk. Some guidelines recommend testing for certain groups, such as those with a personal or family history of premature coronary artery disease.

How Is the Test Done?

A blood sample is taken from a vein, usually in your arm. The blood is sent to a lab where it’s analyzed using an immunoassay method to measure lipoprotein(a) levels. This test doesn’t require fasting, but your doctor may provide specific instructions based on your health status.

What Do Results Mean?

Results are expressed in milligrams per deciliter (mg/dL) or micrograms per milliliter (µg/mL), but exact reference ranges vary by lab. High levels may indicate increased cardiovascular risk, while normal levels don’t guarantee protection. Your doctor will interpret results in the context of your overall health and other risk factors.