Effect of low-density lipoprotein apheresis on patients with peripheral arterial disease. Peripheral Arterial Disease LDL Apheresis Multicenter Study (P-LAS).

ABSTRACT

AIM: The effectiveness of low-density lipoprotein (LDL) apheresis for patients with peripheral arterial disease (PAD) was investigated to confirm a hypothesis based on subjective evidence that the amelioration of blood rheology would be the most contributing factor for improvement in clinical symptoms. Evaluation of the severity of intermittent claudication is difficult because of the lack of an accurate parameter to assess muscle ischemia during exercise, thus we objectively evaluated by non-invasive near-infrared spectroscopy (NIRS) on a treadmill in this study. METHODS: Thirty-one patients with PAD were evaluated for hemostatic function and physiological parameters such as ankle-brachial pressure index (ABI), maximum tolerated walking distance (MTWD) and recovery time (RT) or recovery ability index (RAI) on NIRS. Laboratory tests included plasma assays of total cholesterol, LDL-cholesterol, high-density lipoprotein (HDL) cholesterol, triglyceride, and fibrinogen. The change in red-cell filtration rate was evaluated for the improvement of microcirculation. Statistical analysis was performed using the paired Student's t-test with Bonferroni's correction. RESULTS: A significant improvement in ABI and MTWD was observed after average 9.6+/-0.8 sessions of LDL apheresis treatment and the amelioration of microcirculation in ischemic muscle was objectively evaluated as significant improvement in RAI on NIRS. Rest pain was improved in all 5 patients with Fontaine's classification III or IV. A severe ulcer refractory to usual medications was dramatically diminished in the area by 10 sessions of LDL apheresis and fully healed 5 months after the final LDL apheresis treatment followed by medication. No angiographical change was observed in the arterial occlusive lesions in any patients. CONCLUSIONS: The effectiveness of LDL apheresis on the improvement in physiological parameters such as ABI, MTWD and clinical symptoms in patients with PAD was confirmed. The severity of intermittent claudication was objectively evaluated using non-invasive NIRS. The RT or RAI was useful parameter to evaluate the improvement in the ischemic symptoms of the extremities.