State of the art of lipid apheresis

Currently, 5 different lipid apheresis procedures are available for routine clinical treatment of hypercholesterolemic patients. Unselective plasma exchange is a technically simple extracorporeal circuit, but albumin substitution fluid must be used and there is no high-density lipoprotein (HDL) recovery. Semiselective double filtration with improved size selectivity because of a small-pore secondary filter combines good elimination of low-density lipoprotein (LDL), lipoprotein (a) (Lp[a]), and fibrinogen with adequate HDL recovery; modifications such as thermofiltration, predilution/backflush, or pulsatile flow have been proposed for the improvement of this system. Three highly selective procedures are based on immunologic or electrostatic interactions: immunoadsorption using anti-low-density lipoprotein (LDL) antibodies, chemoadsorption onto dextran sulfate, and heparin-induced LDL precipitation (HELP) apheresis. The features of each system are discussed critically. Lastly, two new developments, Lp(a) immunoadsorption and LDL hemoperfusion using a polyacrylate LDL adsorber compatible with whole blood, are described.