Measurement of Lipoprotein(a) in the Clinical Laboratory

The widespread use of lipoprotein(a) measurements for clinical purposes, such as the prevention of atherosclerotic cardiovascular disease and the investigation of calcific aortic valve disease, is associated with opportunities as well as challenges. Clinical laboratories have adopted approaches that continue to build on the knowledge derived from research and reference laboratories, but in doing so, they must remain responsive to patient-centred requirements and clinician-led expectations. This creates some variations in the ways in which clinical measurements of lipoprotein(a) are undertaken in different settings. This chapter will examine aspects of clinical laboratory measurement that are often taken for granted. Some of these aspects assume increased importance due to the idiosyncrasies associated with the lipoprotein(a) particle. Discussion will include facets of clinical laboratory activity including method selection, quality, safety, clinical application, interpretation and the emerging role of lipoprotein(a) testing within the overall context of healthcare systems. Evidence will be presented to demonstrate improving fitness for purpose of lipoprotein(a) assays, which are largely performed by immunoassays or mass spectroscopy techniques. Comparisons of common products and quality performance indicators will be presented to support professional awareness. Factors affecting interpretation of results will be discussed in the context of medical decision points. Application of these principles will be considered from the perspective of expert guidelines for the assessment and management of atherosclerotic cardiovascular disease and calcific aortic stenosis.