Effect of Atorvastatin on Microcirculation Evaluated byVascular Occlusion Test with Peripheral Near-Infrared Spectroscopy.

Abstract

A total of six consecutive patients with dyslipidaemia who had not received statin therapy (6 males, mean age 71.8±7.4years) were enrolled. All patients were administered atorvastatin and their peripheral microcirculation assessed using VOT with NIRS (NIRO-200NX, Hamamatsu Photonics K.K., Japan) before and after statin therapy. The NIRS probe was attached to the right thenar eminence and brachial artery blood flow was blocked for 3 min at 50mmHg above the resting systolic blood pressure. Maximum and minimum values of NIRS parameters after the VOT were used to determine concentration changes for total haemoglobin (ΔcHb), oxyhaemoglobin (ΔO2Hb), deoxyhaemoglobin (ΔHHb), and tissue oxygenation index (ΔTOI). During the follow-up period (mean 30.3±6.5days), LDL-C level decreased from 129.7±26.3 to 67.5±20.2mg/dL (p-value=0.031), ΔTOI increased from 24.0±5.3 to 33.7±6.3% (p-value=0.023), and ΔO2Hb increased from 16.4±5.3 to 20.0±6.6μmol/L (p-value=0.007). ΔcHb and ΔHHb did not change significantly. ΔO2Hb and ΔTOI were significantly increased during the follow-up period. These findings suggest that ΔO2Hb and ΔTOI could assess the improvement of peripheral microcirculation by statin therapy. Compared to ΔTOI, ΔO2Hb seems to be a more useful parameter to evaluate peripheral microcirculation.