A Predictive Score of Radial Artery Spasm in Patients Undergoing Transradial Percutaneous Coronary Intervention

Objective: 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.

Methods: 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.

Results: 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.

Conclusion: 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.