Risk factors for unintentional rapid catheter advancement through the vertebral artery

Background: Unintentional rapid catheter advancement (URCA) is occasionally performed during endovascular procedures in the posterior circulation. This is a risk factor for vascular perforation or aneurysm rupture; therefore, caution should be exercised. We retrospectively investigated the frequency and risk factors. Methods: Forty-one patients who underwent coil embolization for basilar artery aneurysms at our hospital between January 2015 and June 2023 were included in this study. Vertebral artery (VA) course, vessel diameter, devices used, and underlying diseases causing atherosclerosis were reviewed. Results: Five of 41 (12.2%) patients had URCA. Five patients had a common feature in the course of the VA: The VA from the axial transverse foramen to the transverse foramen of the atlas (V3) was highly tortuous. When the microcatheter passed through this area, the tortuous artery straightened and took the shortest route, resulting in the URCA. Among all cases, similar tortuous vessels were observed in 12 (29.3%) patients, and the frequency of URCA in cases of tortuosity was 41.7%. No significant differences were found between the devices used. Obesity was more frequently observed in patients with URCA. Female sex was considered a risk factor for tortuous vessels. Conclusion: URCA should be considered in cases with severe tortuosity of the V3 portion of the VA. This report also suggests that special attention should be paid to patients with obesity.