To the Editor.
—Recently Olbricht et al1 reported that hypotensive reactions were observed in two severely hypercholesterolemic patients simultaneously treated with angiotensin converting enzyme (ACE) inhibitors and low-density liproprotein (LDL) apheresis using a dextran sulfate—cellulose (DSC) column. Keller et al2 found that with temporary withdrawal of ACE inhibitors 12 to 30 hours before LDL apheresis, the reactions may be avoided.For the past several years in Japan, LDL apheresis with DSC column has been widely applied for treatment of patients with intractable hypercholesterolemia. The major adverse reaction associated with LDL apheresis is temporary hypotension, which has an incidence of approximately 1%.3Retrospective surveillance studies performed by the LDL Apheresis Side Effects Surveillance Group revealed that 13 patients had shown similar hypotensive reactions while receiving ACE inhibitors such as captopril, enalapril, alacepril, and cilazapril. As Olbricht et al suggested, it is likely that these reactions were triggered by