Repeat low density lipoprotein (LDL) apheresis and blood flow determinations in the forearm and leg were performed in 10 patients (age range, 13-49 years; four male, six female) with familial hypercholesterolemia (eight homozygous, two heterozygous). To perform LDL apheresis, plasma was first separated by a polysulphone hollow fiber filter; then, LDL was selectively removed from plasma by dextran sulphate cellulose beads packed in columns. Blood flows in the forearm and leg were determined at rest and during a reactive hyperemia test (peak flow). This test was performed noninvasively by a strain-gauge plethysmograph with semicontinuous registration of arterial blood flow variables before the first apheresis and 3 weeks after the last of six procedures for apheresis. Resting arterial blood flows in the forearm and leg were slightly increased after repeat LDL apheresis (p<0.05). Peak blood flow in the leg significantly increased (+34%, p<0.01). No change in peak blood flow in the forearm was observed. Systolic blood pressures were slightly but significantly reduced (p<0.05); forearm peripheral resistances were also reduced (p<0.05). Flow response was not related to LDL receptor status. Blood and plasma viscosities were determined before and 7 days after the last apheresis. Blood viscosity was significantly reduced after LDL apheresis at shear rates of 11.25-450 sec`.Plasma viscosity did not change. (Circulation 1990;81:610-616) F amilial hypercholesterolemia is an inherited disorder of metabolism characterized by hypercholesterolemia that is due to a marked increase of low density lipoproteins (LDL). This type of hyperlipidemia, in the homozygous form, is refractory to the conventional lipid-lowering treatments and leads to premature development of atherosclerotic cardiovascular disease.1 Nonpharmacologic treatments that have been proposed for the management of patients with familial hypercholesterolemia include plasma exchange2 and LDL apheresis.3-7The aim of these treatments is to produce a marked and sustained cholesterol-lowering effect to retard progression or induce regression of atheromatous plaques.8 There is evidence that blood flow to the
Twenty-two patients with systemic lupus erythematosus and 13 healthy controls were included in a cerebral blood flow study and underwent brain-dedicated single-photon emission computed tomography using 99m technetium-d, l-hexamethylpropylene amine oxime together with a brain computed tomography scan. Plasma levels of antiphospholipid antibodies (lupus anticoagulant and anticardiolipin IgM and IgG antibodies) were also determined. Brain computed tomography showed signs of focal cerebral ischemia in 4 patients (18%), whereas cerebral blood flow by single-photon emission computed tomography was abnormal in 13 of 22 patients (59%), who showed bilateral or monolateral hypoperfusion in the temporo-parietal regions. Patients with abnormal cerebral blood flow had a longer duration of disease than those with normal blood flow (8.9 +/- 1.9 years vs. 5.3 +/- 1.5 years, P < 0.05). Plasma antiphospholipid antibodies were present in 15 patients (68%), but the prevalence was similar in those with normal (6/9, 66%), or abnormal (9/13, 69%) cerebral blood flow. No statistically significant difference in lupus anticoagulant or anticardiolipin antibodies was observed between patients with and without cerebral blood flow abnormalities. Our study shows that patients with systemic lupus erythematosus frequently have cerebral blood flow abnormalities, which could precede those observed by computed tomography. Plasma lupus anticoagulant and anticardiolipin titers were not correlated with normal cerebral blood flow.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.