The Lipoprotein – A test is a test that is conducted to check if there is an elevation in the level of Lipoprotein – A, which can lead to cardiovascular diseases. Lipoprotein is a type of protein that carries cholesterol in the blood. Your doctor might ask you for a Lipoprotein – A test if you have an existing condition of heart or vascular disease, high cholesterol, or if you have had a stroke or heart attack in the past.