In endovascular treatment, guidewires and catheters can cause vascular injury. One of the reasons is that device manipulation is often based on the operator’s experience and intuition. To identify the factors that influence device control and to provide an engineering basis for selecting appropriate manipulations, we evaluated the passability of devices at vascular bends using vascular phantoms with various geometries. In this study, we varied the distance between the catheter and guidewire, as well as the tip orientation, and conducted experiments in which devices were inserted into nine types of silicone vascular phantoms while applying a pushing operation to the guidewire. The passage rate at the bends was used as a quantitative index of operability, and statistical analysis was performed on the resulting data to clarify the effects of vascular geometry and device configuration. The analysis revealed significant differences for all investigated factors. In particular, the passage rate was significantly higher when the device tip direction matched the direction of the vascular bend, suggesting that stable passage is achievable under this condition. Furthermore, even when the tip direction did not match the bend, shortening the distance between the devices to 10 mm tended to suppress the decline in passage rate. These results suggest that using a catheter can help reduce the influence of vascular geometry. The findings indicate that guidewire passability is strongly dependent on operator-controllable factors such as tip orientation and the positional relationship with the catheter.
SHIMADA et al. (Wed,) studied this question.