The first clinical application of a new extracorporeal procedure (HELP) for the selective elimination of low-density lipoproteins by heparin precipitation at acid pH is described. Plasma, obtained by filtration of whole blood through a 0.2 mu filter, is continuously mixed with an equal volume of an acetate buffer (pH 4.85) containing heparin. After removal of the precipitated heparin complex by filtration, excess heparin is adsorbed to a specially developed filter and the clear plasma filtrate is subject to bicarbonate dialysis/ultrafiltration to restore physiologic pH and remove excess fluid. The calculated efficiency for the elimination of low-density lipoproteins from plasma by HELP is 100% and is therefore comparable to conventional plasmapheresis. The HELP system shows a high degree of specificity with over 80% of total protein being returned to the patient. Over 130 treatment procedures have now been performed. Patient compliance and acceptance have been excellent and no major complications have been observed.

In contrast to lovastatin, pravastatin did not accumulate over the study period, which is probably one of the reasons rhabdomyolysis has been reported in lovastatin-treated but not pravastatin-treated transplant patients receiving cyclosporine immunosuppression.