Collateral Flow Modifies EVT Efficacy on LVO Strokes

This study investigated the effect of collateral flow on EVT success on more than 600 patients. The results show that good collateral flow is correlated with EVT efficacy. The authors hypothesize that collateral flow may increase distal pressure helping clot retrieval and reducing clot fragmentations.

Leptomeningeal Collateral Flow Modifies Endovascular Treatment Efficacy on Large-Vessel Occlusion Strokes

Álvaro García-Tornel, Ludovico Ciolli, Marta Rubiera, Manuel Requena, Marian Muchada, Jorge Pagola, David Rodriguez-Luna, Matias Deck, Jesus Juega, Noelia Rodríguez-Villatoro, Sandra Boned, Marta Olivé-Gadea, Estela Sanjuan, Alejandro Tomasello, Carlos Piñana, David Hernández, José Álvarez-Sabin, Carlos A Molina, Marc Ribó

Background and purpose We aim to evaluate if good collateral flow (CF) modifies endovascular therapy (EVT) efficacy on large-vessel stroke. To do that, we used final degree of reperfusion and number of device-passes performed, factors previously associated with better functional outcome, as main outcome measures.

Methods Single-center retrospective study including consecutive stroke patients receiving EVT for anterior circulation large-vessel stroke. CF degree was assessed on CT angiography before EVT using a previously validated 4-grade score. Final degree of reperfusion, using modified Thrombolysis in Cerebral Ischemia (mTICI), and number of device-passes performed were prospectively collected. Multivariable analysis was performed to evaluate the influence of collateral flow degree on final degree of reperfusion and number of device-passes performed.

Results Six hundred twenty-six patients were included in the study; 369 patients (59%) presented good collateral flow on CT angiography. Five hundred twenty-two patients (84%) achieved successful reperfusion (mTICI 2B-3) after EVT, 304 (48%) of them with a final mTICI 2C-3. Median number of device-passes was 2 (interquartile range, 1-3). Good CF was independently associated with better final degree of reperfusion (shift analysis for mTICI0-2A/2B/2C-3%, poor CF 19/38/43 versus good CF 15/32/53, adjusted odds ratio, 1.51 [95% CI, 1.08-2.11]). Poor CF was independently associated with higher number of device-passes performed to achieve successful reperfusion (mTICI2B-3; shift analysis for 1/2/3/4+ device-passes, adjusted odds ratio, 1.59, [95% CI, 1.09-2.31]) and complete reperfusion (mTICI2C-3; shift analysis for 1/2/3/4+ device-passes, adjusted odds ratio, 1.70 [95% CI, 1.04-2.90]).

Conclusions Patients with good CF treated with EVT experience higher rates of successful reperfusion with lower number of device-passes. CF may facilitate thrombus retrieval and prevent distal embolization of clot fragments, improving device-passes efficacy.

Read the full paper here:

García-Tornel Á, Ciolli L, Rubiera M, et al. Leptomeningeal Collateral Flow Modifies Endovascular Treatment Efficacy on Large-Vessel Occlusion Strokes. Stroke. 2021;52(1):299-303. doi:10.1161/STROKEAHA.120.031338

At NICO.LAB we believe Collateral flow is a vital biomarker when triaging stroke patients and determining who is eligible for EVT. This paper strengthens our beliefs, highlighting the importance of collaterals to determine the efficacy of EVT and therefore the likely patient outcome.

See our Collateral assessment solution