# The Prevalence of Difficult Vascular Anatomy in Transulnar Versus Transradial Access for Cardiac Catheterization in Propensity Score‐Matched Cohorts

## TL;DR

This study found that transulnar artery access is better than transradial access for cardiac procedures when dealing with difficult forearm artery anatomy.

## Contribution

The study compares the prevalence of difficult vascular anatomy in transulnar versus transradial access using propensity score-matched cohorts.

## Key findings

- DVA was significantly more prevalent in transradial access compared to transulnar access.
- After propensity score matching, second-degree DVA remained more common in transradial access.
- Transulnar access may be a superior alternative for cardiac procedures with difficult anatomy.

## Abstract

Transradial access (TRA) is used with a Class IA recommendation for coronary angiography (CA) or percutaneous coronary intervention (PCI). Difficult vascular anatomy (DVA) of the forearm arteries is a challenge to its success. Transulnar artery access (TUA) may constitute a viable alternative.

In this single‐center study, we retrospectively compared the prevalence of DVA at the forearm arteries in 2565 consecutive cases of CA/PCI (2403 TRA and 162 TUA) between 2019 and 2022. DVA was classified as zeroth‐degree if the forearm could be passed with a standard 0.035″ guidewire. First‐degree was defined if a standard 0.035″ guidewire had to be switched to a hydrophilic 0.035″ or a 0.018″ guidewire to successfully reach the brachial artery and second‐degree DVA if the forearm arteries could not be passed with any guidewire leading to procedural failure.

In the overall cohort, DVA was significantly more prevalent in TRA versus TUA (zeroth‐degree, first‐degree, second‐degree: 90.3%, 7.2%, and 2.5% vs. 96.9%, 3.1%, and 0%, respectively, p = 0.008). After 4:1 propensity score matching, second‐degree DVA remained more prevalent in TRA versus TUA (2.9% (n = 648) vs. 0% (n = 162, p < 0.001)).

In our retrospective analysis, primary TUA was found to be superior to TRA regarding DVA at the forearm arteries. TUA may present a superior alternative to TRA for CA/PCI in the era of ultrasound‐guided arterial access.