Differential Predictors of Severe Versus Milder Radial Artery Spasm: Insights From a Large Contemporary Distal Radial...

Radial artery spasm remains a frequent procedural challenge in transradial intervention; however, its predictors may differ for severe and milder forms of spasm. This distinction is poorly characterized, particularly in contemporary distal radial access (dRA) populations.

Hereby we intend to approach the predictors of these two types of radial artery spasm.

This prospective single-center study enrolled 291 consecutive patients planned to undergo dRA (successful in 282 [96.9%] and converted to conventional access [cRA] in nine [3.1%] patients). Spasm was systematically graded via completion angiography using a 4-point scale (0: < 30%, 1: 30%-50%, 2: 50%-70%, 3: > 70% narrowing). Multivariable logistic regression was used to identify the independent predictors of severe spasm (> 70%) and any spasm (≥ 30%).

Severe spasms occurred in 91 patients (31.3%), and spasms in 226 patients (77.7%). The predictor profiles differed substantially according to severity. For severe spasms, the independent predictors were younger age (OR: 0.949 per year; 95% CI: 0.926-0.973; p < 0.001), lower body mass index (BMI (OR: 0.915 per kg/m², 95% CI: 0.863-0.970; p = 0.003), and absence of diabetes (OR: 0.495, 95% CI: 0.253-0.970; p = 0.040). For any spasm, the predictors were: female sex (OR: 2.34, 95% CI: 1.15-4.761.15-4.76; p = 0.019), younger age (OR: 0.973, 95% CI: 0.947-0.999; p = 0.043), and interventional procedures (OR: 2.55, 95% CI: 1.11-5.87; p = 0.028). The study was not designed or powered to compare access sites (dRA vs. cRA) because of the extreme cohort imbalance (n = 9 cRA). These findings may enable operators to tailor prophylactic measures based on patient-specific risk profiles. No vascular rupture or radial artery occlusion was observed.

In a contemporary dRA cohort, the predictors of radial artery spasm differed according to severity. While younger age is a universal risk factor, severe spasm is uniquely associated with lower BMI and non-diabetic status, whereas milder spasms are linked to female sex and procedural complexity. These findings may enable operators to tailor prophylactic measures based on patient-specific risk profiles.