Muscle microcirculation alterations and relation to dipping status in newly diagnosed untreated patients with arterial hypertension - A pilot study

Objective The importance of abnormalities observed in the microcirculation of patients with arterial hypertension (AH) is being increasingly recognized. The authors aimed to evaluate skeletal muscle microcirculation in untreated, newly diagnosed hypertensive patients with Near Infrared Spectroscopy (NIRS), a non-invasive method that evaluates microcirculation. Methods We evaluated 34 subjects, 17 patients with AH (13 males, 49±13y, BMI: 26±2 kg/m2) and 17 healthy controls (12 males, 49±15y, BMI: 25±3 kg/m2). The thenar muscle tissue oxygen saturation (StO2, %) was measured by NIRS before, during and after 3-minute vascular occlusion to calculate oxygen consumption rate (OCR, %/min), endothelial function (EF, %/min) and reactive hyperemia time (RHT, min). The dipping status of hypertensive patients was assessed. Results The RHT differed between AH patients and healthy subjects (2.6±0.3 vs 2.1±0.3 min, p<.001). Dippers had higher EF than non-dippers (939±280 vs 710±164%/min, p=.05). Conclusions The study suggests an impaired muscle microcirculation in newly diagnosed, untreated AH patients. This article is protected by copyright. All rights reserved.