Association of Estimated Arterial Stiffness with Collateral Status and Functional Outcome after Endovascular Thrombectomy: A Secondary Analysis of the OPTIMAL-BP Trial.

Abstract

Purpose: Estimated pulse wave velocity (ePWV) is a surrogate of arterial stiffness that may influence stroke outcomes and potentially affect collateral circulation. We examined the association of ePWV with collateral status and 3-month functional outcome after successful endovascular thrombectomy and explored the contribution of collateral status to this relationship across blood pressure (BP) management strategies.

Materials and methods: In this secondary analysis of the Outcome in Patients Treated With Intra-Arterial Thrombectomy-Optimal Blood Pressure Control trial, 285 patients were analyzed. Collateral status was assessed using the Tan scale (poor, 0-1; good, 2-3). Poor functional outcome was defined as 3-month modified Rankin Scale score of 3-6. Multivariable logistic and mediation analyses were performed to evaluate the association between ePWV and functional outcomes and to explore direct and indirect pathways.

Results: A total of 285 patients were included (mean age, 73.3±11.3 years; 40.4% women). Each 1 m/s increase in ePWV was associated with poor collaterals (adjusted odds ratio [OR] 1.276, 95% confidence interval [CI] 1.083-1.503) and poor functional outcome (adjusted OR 1.338, 95% CI 1.121-1.597). In mediation analyses, collateral status accounted for only a small proportion of the association between ePWV and poor functional outcome (indirect effect: adjusted β 0.022, 95% CI 0.001-0.053), whereas the direct effect remained significant (adjusted β 0.237, 95% CI 0.115-0.359). Neither the direct effect of ePWV on functional outcome nor the indirect effect through collateral status differed according to BP management strategy.

Conclusion: Higher ePWV was associated with poor collateral status and unfavorable functional outcome after successful reperfusion. Collateral status accounted for only a small proportion of the observed association between ePWV and functional outcome.