This Article Full Text Full Text (PDF) All Versions of this Article: 39/12/3231    most recent STROKEAHA.108.521054v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Barreto, A. D. Articles by Savitz, S. I. Search for Related Content PubMed PubMed Citation Articles by Barreto, A. D. Articles by Savitz, S. I. Pubmed/NCBI databases Medline Plus Health Information Angioplasty Related Collections Acute Cerebral Infarction Emergency treatment of Stroke Angiography Thrombolysis Angioplasty and Stenting

(Stroke. 2008;39:3231.)
© 2008 American Heart Association, Inc.

Original Contributions

Thrombus Burden Is Associated With Clinical Outcome After Intra-Arterial Therapy for Acute Ischemic Stroke

Andrew D. Barreto, MD; Karen C. Albright, DO, MPH; Hen Hallevi, MD; James C. Grotta, MD; Elizabeth A. Noser, MD; Aslam M. Khaja, MD; Hashem M. Shaltoni, MD; Nicole R. Gonzales, MD; Kachi Illoh, MD, MPH; Sheryl Martin-Schild, MD, PhD; Morgan S. Campbell, III, MD; Raymond U. Weir, MD Sean I. Savitz, MD

From the Department of Neurology (A.D.B., H.H., J.C.G., E.A.N., N.R.G., K.I., S.M.-S., M.S.C. III, S.I.S.), Stroke Division, University of Texas at Houston Medical School; Department of Neurosciences (K.C.A.), University of California at San Diego; Department of Neurology (A.M.K.), University of Illinois at Chicago Medical School; Department of Radiology (H.M.S.), Baylor University School of Medicine, Houston, Tex; and Department of Radiology (R.U.W.), University of Texas at Houston Medical School.

Correspondence to Andrew D. Barreto, MD, Department of Neurology, Stroke Division, University of Texas–Houston Health Science Center, 6431 Fannin St, MSB 7.124, Houston, TX 77030. E-mail andrew.d.barreto{at}uth.tmc.edu

Background and Purpose— Studies have established a relation between recanalization and improved clinical outcome in acute ischemic stroke patients; however, intra-arterial clot size has not been routinely assessed. The aim of the study was to determine the impact of intra-arterial thrombus burden on intra-arterial treatment (IAT) and clinical outcome.

Methods— A retrospective review of our IAT stroke database included procedure time, recanalization, symptomatic intracranial hemorrhage, poor outcome (modified Rankin Scale score 4 at discharge), and mortality. The modified Thrombolysis in Myocardial Infarction thrombus grade was dichotomized into grades 0 to 3 (no clot or moderate thrombus, <2 vessel diameters) versus grade 4 (large thrombus, >2 vessel diameters).

Results— Data were collected on 135 patients with thrombus grading. The baseline median National Institutes of Health Stroke Scale score was higher in patients of grade 4 compared with grades 0 to 3 (19 vs 17, P=0.012). Grade 4 thrombi required longer (median, range) times for IAT (113, 37 to 415 minutes vs 74, 22 to 215 minutes, respectively; P<0.001) and higher rates of mechanical clot disruption (wire, angioplasty, snare, stent, or Merci retriever) compared with grades 0 to 3 (76% vs 53%, P=0.005). There were no differences in rates of symptomatic intracranial hemorrhage (6.6% vs 4.1%, P=0.701) or recanalization (50% vs 61%, P=0.216) in grade 4 versus grades 0 to 3. Multivariate analysis adjusted for age, baseline National Institutes of Health Stroke Scale score, and artery of involvement showed that grade 4 thrombi were independently associated with poor outcome (odds ratio=2.4; 95% CI, 1.06 to 5.57; P=0.036) and mortality (odds ratio=4.0; 95% CI, 1.2 to 13.2; P=0.023).

Conclusions— High thrombus grade as measured by the modified Thrombolysis in Myocardial Infarction criteria may be a risk factor that contributes to poor clinical outcome.

Key Words: thrombus burden • thrombosis • thrombolysis • stroke • angiography • endovascular treatment • outcome