Notice of RetractionAssessment of Time-Dependent Elastance of Superficial Arterial Wall by an External Vibration Stimulation
The aim of the study was to propose an external vibration method for measuring the time-dependent elastance of the arterial wall, an arterial stiffness indicator. A minute sinusoidal displacement with a frequency range from 50 to 100 Hz was used to impose on a superficial radial artery. At maximum amplitude of the sinusoidal displacement, the ratio of the reactive force from the radial wall and the maximum amplitude was inversely proportional to squared angular frequency of the sinusoidal displacement. Furthermore, the wall elastance could be determined from the relationship between the ratio of (reactive force / displacement) and the squared angular frequency. In twenty healthy subjects, the amplitude of the radial wall elastance was found to be a function of time or arterial blood pressure either at the room temperature or just after 5-minute cold stress. In addition, maximum of the time varying wall elastance within a cardiac cycle was significantly greater merely after the cold stress than at the room temperature (5.82±2.24 × 105 versus 3.86±1.26 × 105 dyne/cm, (p<;0.001). Briefly, the proposed method can be applied to obtain the time varying wall elastance of a superficial artery, and a 5-minute cold stress not only elevates the amplitude of wall elastance but also augments its dynamic range in a heartbeat period.