Direct transfer to angiography after stroke improves outcomes, hospital workflow

Direct transfer to an angiography suite within 6 hours of stroke onset increased rates of endovascular therapy, reduced hospital workflow time and enhanced clinical outcomes, according to findings published in JAMA Neurology.

“Research assessing optimized workflows has led to a newly proposed paradigm in the acute treatment of patients with severe stroke: direct transfer to angiography suite,” the researchers wrote. “Regardless of the protocol details, [direct transfer to angiography suite] has been consistently shown to be effective in decreasing [door to puncture] time to as low as 16 minutes without safety concerns. The effect of [direct transfer to angiography suite] on long-term functional outcomes varies between published nonrandomized studies and is still unclear.”

In the ANGIO-CAT randomized clinical trial, Manuel Requena, PhD, of the Hospital Universitari Vall d’Hebron and the Vall d’Hebron Insitut de Recerca in Barcelona, and colleagues aimed to determine whether patients with suspected acute ischemic stroke due to large vessel occlusion upon admission experienced better long-term clinical outcomes with a direct transfer to angiography suite workflow compared with those who underwent a traditional neuroimaging in-hospital workflow. The investigator-initiated, single-center, evaluator-blinded study enrolled participants between September 2018 and November 2020 and concluded following a preplanned interim analysis. The researchers performed final follow-up in February 2021.

The trial screened 466 consecutive patients with acute stroke and included 174 of those patients, all of whom had suspected large vessel occlusion acute stroke and were admitted within 6 hours of symptom onset. The researchers randomly assigned patients 1:1 to follow the direct transfer to angiography suite workflow (n = 89) or the conventional workflow (n = 85), in which patients underwent direct transfer to CT imaging, with usual imaging performed and endovascular treatment indication determined, to evaluate the indication for endovascular treatment. They grouped patients based on whether they were transferred from a primary center or directly admitted.

Requena and colleagues used a shift analysis as the primary outcome; this analysis evaluated the distribution of the 90-day, 7-category (0 [no symptoms] to 6 [death]) modified Rankin Scale score regardless of receipt of endovascular treatment (modified intention-to-treat population). Secondary outcomes included the rate of endovascular treatment and door-to-arterial puncture time. Safety outcomes included 90-day mortality and rates of symptomatic intracranial hemorrhage.

mean age 73.4 years (range, 19-95 years) 44.8% were women (n = 78). mean onset-to-door time among these patients of 228 minutes, with a median National Institutes of Health Stroke Scale score of 18 at admission (IQR, 14-21).

Among patients in the modified intention-to-treat population, Requena and colleagues reported that endovascular treatment was performed for all 74 patients in the direct to angiography suite group and for 64 patients (87.7%) in the conventional workflow group (P = .002). The direct to angiography suite workflow reduced the median door–to–arterial puncture time (18 minutes [IQR, 15-24 minutes] vs. 42 minutes [IQR, 35-51 minutes]; P < .001) and door-to-reperfusion time (57 minutes [IQR, 43-77 minutes] vs. 84 minutes [IQR, 63-117 minutes]; P < .001). Additionally, the direct to angiography suite workflow lowered disability severity across the range of the modified Rankin Scale (adjusted common OR = 2.2; 95% CI, 1.2-4.1). The researchers reported that safety variables were comparable between groups.

“The improvements in clinical outcomes shown in our study are substantial and are likely due to major reasons: increasing the rate of EVT by avoiding overselection in treatment indication and reducing in-hospital workflow,” the researchers wrote. “Similar to previously published studies, [direct transfer to angiography suite] decreased [door-to-puncture] time to as low as 18 minutes and decreased door-to-reperfusion time to less than 1 hour.”

Requena and colleagues acknowledged several limitations of their study, including constrained funding that prevented external monitoring of the data beyond the data safety monitoring board and the early termination of the trial, which made it underpowered to identify differences between groups regarding the safety variables.

“Multicentric international randomized clinical trials are being developed to determine the replicability of our findings,” the researchers wrote. “For patients with [large vessel occlusion] admitted within 6 hours after symptom onset, this randomized clinical trial found that, compared with conventional workflow, the use of [direct transfer to angiography suite] increased the odds of patients undergoing [endovascular treatment], decreased hospital workflow time and improved clinical outcome.”