How is it used?
The PLAC® test, along with other lab tests and clinical information, is used to determine the risk of heart attack or stroke.
When is it ordered?
The PLAC® test is ordered for patients considered to be at borderline or high risk for heart attack or stroke, based on their clinical history. Some of the risk factors for cardiovascular disease include:
- Family history of early heart disease or stroke
- High blood pressure
- Borderline high or elevated cholesterol
- Men above 45 years and women above 55 years
What does the test result mean?
Atherosclerosis, or hardening of the arteries, is caused by the production of a fatty deposit, called a plaque. Inflammation of the arteries leads to the production of an enzyme called Lp-PLA2. If the level of Lp-PLA2 in the blood is high, this may indicate a higher risk that the plaque can rupture and be released into the blood stream, where it can lead to heart attack or stroke.
The PLAC® test measures the level of Lp-PLA2 enzyme and, if elevated, suggests a higher risk that the arterial plaque may rupture. Individuals who have an elevated PLAC® result and one or more risk factors for cardiovascular disease have more than twice the risk of having a heart attack.
If the PLAC® result is elevated and the individual has high blood pressure, the risk for stroke increases more than 6-fold.
Is there a charge for the test?
This test is not covered by the provincial health insurance plans, but it may be covered by extended health insurance plans. Contact LifeLabs to find out about the current fee for the test.
Is there anything else I should know?
Half of heart attacks occur in people with normal cholesterol levels and most cardiovascular events are due to plaque rupture.
- Zalewski A and Macphee C. Role of lipoprotein-associated phospholipase A2 in atherosclerosis: biology, epidemiology, and possible therapeutic target. Arterioscler Thromb Vasc Biol (2005) 25: 923-931.
- Davidson MH et al. Consensus panel recommendation for incorporating lipoprotein associated phospholipase A2 testing into cardiovascular disease risk assessment guidelines. Am J Cardiol (2008) 101: 51F-57F.
- Sachdeva A et al. Lipid levels in patients hospitalized with coronary heart disease: an analysis of 136,905 hospitalizations in Get With The Guidelines. Am Heart J (2009): 157: 111-117.e2
- Goldstein LB et al. Guidelines for the primary prevention of stroke: a guideline for healthcare professionals from the American Heart Association/American Stroke Association. Stroke (2011) 42: 517-584.
PLAC® is a registered trademark of diaDexus