How to optimize lipoprotein apheresis treatment – A second look

BackgroundLipoprotein apheresis (LA) is used in hypercholesterolemic patients suffering from cardiovascular disease (CHD) if a modified diet and lipid-lowering drug regimens had failed. During the first LA treatments LDL-cholesterol (LDL-C) and lipoprotein (a) (Lp(a)) can be decreased very effectively when using generally accepted formulas for calculating plasma (PV) (e.g. Pearson) or blood volumes (BV) as a basis for calculating treatment volume (e.g. Nadler). With respect to LDL-C and Lp(a) levels after LA treatment not all treated patients on steady state with apheresis treatment procedures may achieve the desired target concentrations for LDL-C (<70 mg/dl) and Lp(a) (<30 mg/dl). Are there further ways to increase the effectiveness of LA?MethodsOver months or years of LA the treated volumes were stepwise increased in patients to achieve target cholesterol concentrations but not sufficiently in all cases. Therefore the patients' actual LA treatment volumes were compared to the calculated PV or BV. To possibly optimize the treatment capacity of LA procedures independent of calculated PV or BV the capacity threshold was determined in addition. During LA procedures every 20 min cholesterol, triglycerides, LDL-C, HDL-C and Lp(a) concentrations were determined and related to the hematocrit to exclude dilution effects.ResultsIn patients undergoing regular LA treated volumes vs. calculated volumes were different: for PV 28 ± 18% (n = 7); for BV 28 ± 20% (n = 6). The mean treated volumes were 1.3 fold larger than the calculated volumes to achieve cholesterol target levels in most LA treatments. With respect to the capacity threshold we observed in only 1 of 13 patients an ineffective long treatment time. No LA procedure failed due to exhausted capacity.ConclusionsLipoprotein apheresis treatment is a very effective treatment procedure in lowering LDL-C and Lp(a). However, not in all procedures the optimal treatment volume for LA patients may be calculated. However calculations of PV and BV are more or less error-prone. An increase of 1.3 fold in the calculated volumes may be the first step in optimizing individual LA treatment options. In addition, to exclude an exhaustion of LA procedures the determination of the individual capacity threshold in every LA patient may be further helpful to adjust treatment volumes. To substantiate our demand on changed treatment volumes further data are necessary.