Effects of losartan on low-density lipoprotein apheresis

The negative charges of dextran sulfate cellulose (DSC) used for low-density lipoprotein (LDL) apheresis activate the intrinsic coagulation pathway, accompanied by bradykinin production. This study was undertaken to see whether an antagonist of angiotensin receptor (AT1), losartan, could be safely used in a patient treated by DSC-LDL apheresis. Losartan (50 mg/day) was given to a patient with coronary heart disease who had been treated by DSC-LDL apheresis and had experienced an anaphylactoid reaction by administration of an angiotensin converting enzyme inhibitor. The effects of losartan on blood pressures and humoral factors were examined by comparing these parameters between apheresis with and without losartan. Blood pressures and plasma levels of bradykinin, renin, and aldosterone were measured before and at 1,000, 2,000, and 3,000 ml of plasma treatment. Bradykinin levels during LDL apheresis tended to be higher with losartan than without losartan (without versus with, 529 +/- 121 [n = 4, mean +/- SE] pg/ml vs. 1,058 +/- 49 at the 2,000 ml stage, p < 0.01). The rise of plasma renin activity with losartan (221 +/- 26% at the 3,000 ml stage) was significantly greater than that without losartan (144 +/- 2.4%). Mean blood pressure decreased by 7% during apheresis with losartan, but blood pressure reduction was not accompanied by any complaints. These results suggest that AT1 receptor antagonists are safely used in patients treated by DSC-LDL apheresis.