A predictive score of radial artery spasm in patients undergoing transradial percutaneous coronary intervention

Radial artery spasm may hinder completion of transradial angiography or PCI, leading to access site crossover, prolonged procedure times and complications. The aim of this study was to derive a radial artery spasm risk score in patients undergoing elective percutaneous coronary intervention (PCI), prospectively validate it, and apply it in a real-life clinical setting.

The study population consisted of 3 cohorts of patients undergoing elective PCI with transradial access: the derivation cohort (N=1006), the validation cohort (N=576) and the intervention cohort (N=140), consisting of patients with high risk score, in whom intensified spasm-preventive measures were applied.

Multivariable analysis in the derivation cohort showed that 5 weighted factors could be used to construct a risk score for spasm: body-mass index, height, current smoking, hypertension and peripheral artery disease (c-statistic 0.945, with an optimal cut-off of 4). In the validation cohort, the cut-off of 4 predicted spasm with a sensitivity of 84.5% and a specificity of 74.7%. In the intervention cohort, which included only patients with a spasm-risk score of ≥4, the rate of spasm was drastically reduced (odds ratio 0.32, 95% confidence interval 0.17-0.61), compared to the corresponding high spasm risk subgroup of patients of the validation cohort.

A spasm risk score can be used to predict radial artery spasm during elective transradial PCI. Using this score, a high spasm risk patient subgroup can be identified, where intensive spasm-preventive measures can lead to a significant reduction in the frequency of spasm.