Thermographic evaluation of the hemodynamic effect of the antithrombotic drug cilostazol in peripheral arterial occlusion.

Cilostazol (6-[4-(1-cyclohexyl-1H-tetrazol-5-yl) butoxy]-3,4-dihydro-2(1H)-quinolinone, OPC-13013) was evaluated experimentally to be effective in increasing blood flow in arterial occlusive disease. The hemodynamic effect of the drug on peripheral arterial occlusion was examined using a non-invasive thermographic technique over a certain period of time. The study included 10 patients with peripheral arterial occlusion, 7 with thromboangiitis obliterans and 3 with arteriosclerosis obliterans. Cilostazol was administered at 200 mg/day for 6 successive weeks to 7 patients (10 lower limbs and 1 upper limb) and at 100 mg/day for 6 weeks to 2 patients (3 lower limbs) and 4 weeks to 1 (1 lower limb), and the skin temperature and skin blood flow were measured in the limbs of these patients. The 200-mg/day dose brought about elevation of the two parameters at 4 and 6 weeks. The increase in skin temperature in the leg and foot at 6 weeks was statistically significant (p less than 0.05, t-test), and the increase in skin blood flow was also significant in the leg (p less than 0.05) and foot (p less than 0.1). Such increase was obtained at the lower dose of 100 mg/day, but the number of cases was too small to statistically analyze patient response.