Blood Tests for Cardiovascular Conditions
The concentration of several types of fats (lipids) in the blood can indicate risk factors for heart disease. A typical lipid profile test usually measures the levels of low-density lipoprotein (LDL, also known as “bad” cholesterol”), high-density lipoprotein (HDL, also known as “good” cholesterol), total cholesterol (the sum of the different forms of cholesterol in the blood), and triglycerides (another type of fat, high levels of which may increase the risk of heart disease).
A patient’s blood level of lipoprotein (a), a type of LDL cholesterol, is usually genetically determined. High levels may indicate a genetic predisposition toward heart disease. If a patient has a family history of heart disease that is not explained by traditional risk factors, or if medication has not been effective at reducing their overall LDL levels, they may receive a blood test specifically to analyze lipoprotein (a) levels.
Inflammation in the body can increase a patient’s risk of developing atherosclerosis (narrowed and hardened arteries). C-reactive protein (CRP) is produced by the liver as part of the body’s inflammatory response, and a high level (usually higher than 3 milligrams per liter of blood) can indicate an increased risk of heart disease. This is a different test than the CRP test used to detect rheumatologic diseases.
Fibrinogen helps to form blood clots; high levels of fibrinogen may increase the risk of blood clots forming where they shouldn’t and potentially blocking blood flow. This in turn makes a stroke or heart attack more likely.
If the heart is weak or damaged, the heart and blood vessels produce higher levels of a chemical called B-type natriuretic peptide (BNP). Analyzing BNP levels may help physicians diagnose heart failure or assess the risk of heart attack or other events.
There are several types of LDL cholesterol and HDL cholesterol that can be tested by special analysis. For example, a “dense” type of LDL cholesterol may be especially harmful.
Apolipoprotein B (apo B) levels can be measured by a special blood test. Apo B is similar to LDL cholesterol, and this test can sometimes give additive information.