EFFICACY OF LIPID APHERESIS - DEFINITIONS AND INFLUENCING FACTORS

The comparison of efficiency of currently available lipid apheresis sy stems has been hampered by different definitions of efficacy and poorl y controlled apheresis conditions. This paper suggests definitions of efficacy and standardization of ifs determinants. The acute efficacy o f risk factor reduction reflects the relative decrease of pathogen by a single treatment session compared to preapheresis levels. Standardiz ation of treated plasma volume in relation to the patients plasma volu me and correction of changes in plasma volume during the procedure are mandatory. Its determination is most useful in the technical evaluati on of new systems. The long-term efficacy of risk factor reduction as compared to baseline is determined by mean interapheresis levels of e. g. LDL-C in the pseudo-steady-state after about 3 months of regular tr eatment. it is the major criterion for potential regression of coronar y artery disease and absolute average plasma levels of 120 less than o r equal to mg/dl LDL-C should be attained It is influenced by the acut e efficacy of the system, apheresis frequency and rebound kinetics. Th e clinical efficacy is defined by apheresis induced reduction of coron ary morbidity and mortality. It is influenced by long-term risk factor reduction, the selectivity of the system as well as the control of no n-lipid risk factors. Apheresis related effects on coronary artery dis ease comprise functional improvements of hemorheology and vasomotion a s well as morphological benefits like regression of luminal narrowing and plaque stabilization. In conclusion, the acute efficacy of apheres is systems should be determined under strictly controlled conditions; however, as apheresis independent factors influence long-term efficacy and, even more so, clinical efficacy of the treatment, differences be tween the available systems are blurred so that factors like costs and ease of handling may eventually significantly influence the choice of procedure.