ABSTRACT
Lp(a) is a structurally complex particle which resembles LDL, but which also contains
the distinctive glycoprotein apo(a). Apo(a) is characterized by a variable number
of repeated kringle domains, which gives rise to differently-sized Lp(a) isoforms
in the population. Although epidemiological studies indicate that elevated Lp(a) concentration
and/or small apo(a) isoform sizes increase the risk of coronary heart disease (CHD),
a causal role for Lp(a) in CHD remains unproven. This is largely due to the difficulty
in establishing a relevant animal model to probe Lp(a) function, and the lack of intervention
studies in which Lp(a) concentrations are lowered and outcomes followed. The accumulation
of apo(a)/Lp(a) in arterial lesions has provided the rationale for numerous in vitro studies aimed at dissecting its function in this milieu. These studies have resulted
in the proposal of numerous proatherogenic, prothrombotic and antifibrinolytic roles
for both native and modified apo(a)/Lp(a). Although characterization of Lp(a) in the
general population is not presently justified, Lp(a) analysis in patients at risk
for CHD may be warranted.
KEYWORDS
Lipoprotein(a) - apolipoprotein(a) - coronary heart disease - atherosclerosis