Predictors of functional dependence despite successful revascularization in large-vessel occlusion strokes

Stroke. 2014 Jul;45(7):1977-84. doi: 10.1161/STROKEAHA.114.005603. Epub 2014 May 29.


Background and purpose: High revascularization rates in large-vessel occlusion strokes treated by mechanical thrombectomy are not always associated with good clinical outcomes. We evaluated predictors of functional dependence despite successful revascularization among patients with acute ischemic stroke treated with thrombectomy.

Methods: We analyzed the pooled data from the Multi Mechanical Embolus Removal in Cerebral Ischemia (MERCI), Thrombectomy Revascularization of Large Vessel Occlusions in Acute Ischemic Stroke (TREVO), and TREVO 2 trials. Successful revascularization was defined as thrombolysis in cerebral infarction score 2b or 3. Functional dependence was defined as a score of 3 to 6 on the modified Rankin Scale at 3 months. We assessed relationship of demographic, clinical, angiographic characteristics, and hemorrhage with functional dependence despite successful revascularization.

Results: Two hundred and twenty-eight patients with successful revascularization had clinical outcome follow-up. The rates of functional dependence with endovascular success were 48.6% for Trevo thrombectomy and 58.0% for Merci thrombectomy. Age (odds ratio, 1.04; 95% confidence interval, 1.02-1.06 per 1-year increase), National Institutes of Health Stroke Scale score (odds ratio, 1.08; 95% confidence interval, 1.02-1.15 per 1-point increase), and symptom onset to endovascular treatment time (odds ratio, 1.11; 95% confidence interval, 1.01-1.22 per 30-minute delay) were predictors of functional dependence despite successful revascularization. Symptom onset to reperfusion time beyond 5 hours was associated with functional dependence. All subjects with symptomatic intracranial hemorrhage had functional dependence.

Conclusions: One half of patients with successful mechanical thrombectomy do not have good outcomes. Age, severe neurological deficits, and delayed endovascular treatment were associated with functional dependence despite successful revascularization. Our data support efforts to minimize delays to endovascular therapy in patients with acute ischemic stroke to improve outcomes.

Clinical trial registration url: Unique identifier: NCT00318071, NCT01088672, and NCT01270867.

Keywords: stroke.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Brain Infarction / epidemiology
  • Brain Infarction / physiopathology
  • Brain Ischemia / drug therapy
  • Brain Ischemia / epidemiology*
  • Brain Ischemia / physiopathology
  • Cerebral Revascularization* / standards
  • Cerebral Revascularization* / statistics & numerical data
  • Clinical Trials as Topic
  • Female
  • Humans
  • Male
  • Middle Aged
  • Multicenter Studies as Topic
  • Predictive Value of Tests
  • Recovery of Function / physiology*
  • Severity of Illness Index
  • Stroke / drug therapy
  • Stroke / epidemiology*
  • Stroke / physiopathology
  • Thrombectomy* / standards
  • Thrombectomy* / statistics & numerical data
  • Thrombolytic Therapy* / standards
  • Thrombolytic Therapy* / statistics & numerical data

Associated data