Pleiotropic effects of regular lipoprotein-apheresis.

Background: Lipoprotein(LP)-apheresis is the treatment of choice in patients suffering from severe familial hypercholesterolemia. A wide range of mechanisms has been claimed to be responsible for the known clinical benefit.

Methods: Patients suffering from heterozygous familial hypercholesterolemia undergoing LP-apheresis either with direct adsorption of lipoproteins (DALI) or dextran sulfate (DS) were examined. A total volume of 10 l blood was exchanged. Non-lipid effects, mainly concerning endothelial function (circulating endothelial cells, circulating endothelial progenitor cells, flow-mediated vasodilation, microalbuminuria) as well as left ventricular ejection fraction and homocysteine were assessed.

Results: A single LP-apheresis session improves paradox contractile response in statin intolerant patients, but not in those on regular statin therapy. In contrast, over a 6-months follow-up after treatment initiation, all the examined parameters (circulating endothelial cells, circulating endothelial progenitor cells, flow mediated vasodilatation, homocysteine, microalbuminuria and left ventricular ejection fraction) improved. When available, a comparison between DS vs. DALI was performed. In none of the subgroups a significant difference was noted.

Discussion: These findings indicate that beyond the well known lipid/lipoprotein lowering action the broad spectrum of functional tests examined reflecting mainly endothelial function is significantly improved by LP-apheresis treatment on the long-term and seems to be a key underlying reason for the clinical improvement seen in these patients.