While trans-radial access (TRA) offers advantages in cerebral angiography, its efficiency is compromised by uncharacterized neurovascular anatomical barriers. This study investigates the impact of arterial tortuosity on procedural efficiency in TRA cerebral angiography. In a retrospective cohort of patients undergoing TRA cerebral angiography at our center (Oct 2023-Apr 2024), vascular tortuosity was classified via intraprocedural angiography. Procedural efficiency was stratified by total fluoroscopy time (Easy to Extremely Difficult grades). Multivariable ordinal regression and mediation analyses identified anatomical predictors and mechanistic pathways. This study comprised 170 patients (mean age 60.66±12.62 years; 31.76% female). Procedural success was achieved in all patients. After adjusting for other confounders, dual subclavian-brachiocephalic tortuosity was found to be independent predictor of increasing procedural inefficiency. This variant prolonged total fluoroscopy time primarily through delayed left-vessel catheterization, with superselective catheterization of the left subclavian artery (SC-LSA) and superselective cannulation of the Left common carotid artery (SC-LCCA) jointly mediating 95.5%-99.2% of the total effect (parallel path coefficients a1/a2/b1/b2 all p0.05), confirming complete mediation. No statistical difference existed between SC-LSA and SC-LCCA's mediating effects (contrast effect c1 95% CI included zero). Dual subclavian-brachiocephalic tortuosity is a critical remediable obstacle to efficient neurointerventional TRA. Preprocedural screening for this variant combined with torsion-resistant catheter designs may reduce fluoroscopy time, enhancing TRA viability for cerebrovascular diagnostics.
Tian et al. (Mon,) studied this question.