A reduced ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13) concentration at hospital admission may represent an important blood biomarker for predicting poor response to recanalization in patients with acute ischemic stroke, according to a small study published in Neurology.
Investigators enrolled 108 patients with acute ischemic stroke who had received intravenous (IV) thrombolysis with IV tissue plasminogen activator (tPA) for arterial occlusions within the first 4.5 hours following stroke. Blood samples drawn prior to treatment were analyzed for ADAMTS13 activity by ELISA, and investigators evaluated success of recanalization of the occluded vessel at 2 hours following IV-tPA bolus. A total of 78 consecutive patients were treated with endovascular thrombectomy. Complete recanalization in addition to a 3-month modified Rankin Scale score >2 defined futile recanalization.
In the cohort receiving tPA, higher baseline ADAMTS13 levels were associated with a greater likelihood of achieving tPA-induced recanalization (78.1%; 95% CI, 68%-88% vs 70.1%; 95% CI, 61%-79%; P =.021). A logistic regression analysis demonstrated that ADAMTS13 activity >75% and the absence of early ischemic signs independently predicted recanalization (odds ratio [OR] 6.76; 1.52-30.02; P =.012). A reduced ADAMTS13 concentration (<982 ng/mL), in addition to age and the presence of diabetes mellitus, was found to be an independent predictor for futile recanalization in the cohort of patients receiving endovascular therapy (OR 67.4; 95% CI,1.4-3282.1; P =.034). Discrimination and reclassification were improved when investigators added ADAMTS13 concentration to the clinical predictors of futile recanalization and tPA-induced recanalization (integrated discrimination improvement = 28.4% and 10.06%, net reclassification improvement = 107.4% and 61.0%, respectively).
Although participants receiving tPA were randomly selected, it is uncertain whether this small group of patients could be representative of the entire stroke population. Also, the investigators measured ADAMTS13 activity in the first cohort vs ADAMTS13 antigen in the second, and future studies may need to measure these 2 values simultaneously to obtain findings with greater power.
The findings from this study suggest a low ADAMTS13 concentration on presentation of an acute ischemic stroke “might indicate the need for an emergent transfer to a comprehensive stroke center with availability of endovascular treatments.”
Bustamante A, Ning M, García-Berrocoso T, et al. Usefulness of ADAMTS13 to predict response to recanalization therapies in acute ischemic stroke [published online February 14, 2018]. Neurology. doi:10.1212/WNL.0000000000005162