The scientific basis and future of lipoprotein apheresis.

Lipoprotein apheresis plays a vital role in the management of the severe hyperlipidemias that predispose to atherosclerosis. Determinants of efficacy are the acute reduction in lipoproteins achieved by each apheresis procedure, their frequency, and the fractional catabolic rates and hence pool sizes of low-density lipoprotein (LDL) or lipoprotein (a) (Lp(a)) of the patient being treated. A useful criterion of the efficacy of apheresis plus lipid-lowering drug therapy is the decrease in the interval (time-averaged) mean of serum total or LDL cholesterol or Lp(a) between procedures, expressed as the percent decrease in the interval means below the maximal levels of these lipoproteins when off all treatment. Recent advances in lipid-lowering drug therapy may diminish the use of lipoprotein apheresis but will not abolish its unique role as a therapeutic "last chance saloon," especially for children and pregnant women with homozygous familial hypercholesterolemia.