The Impact of Recanalization on Ischemic Stroke Outcome

Abstract

Background and Purpose-For a biomarker to serve as an auxiliary or surrogate outcome measure, it must be tightly correlated with and causally related to functional clinical outcome. Vessel recanalization is a potential surrogate outcome marker for functional outcome in trials of thrombolytic and mechanical recanalization therapies in acute stroke, but the correlation of recanalization and clinical outcome has not been previously systematically reviewed. Methods-Through Medline search, we identified and abstracted recanalization and outcome data from all articles published between 1985 and 2002 that assessed vessel recanalization, either spontaneous or therapeutically induced, in acute ischemic stroke. Results-Fifty-three studies encompassing 2066 patients reported recanalization rates. Recanalization rates categorized according to intervention were: spontaneous (24.1%), intravenous fibrinolytic (46.2%), intra-arterial fibrinolytic (63.2%), combined intravenous-intra-arterial (67.5%), and mechanical (83.6%). Clinical outcome data categorized by success or failure in achieving recanalization was available from 33 articles encompassing 998 patients. Good functional outcomes at 3 months were more frequent in recanalized versus nonrecanalized patients with odds ratio of 4.43 (95% CI, 3.32 to 5.91). Three-month mortality was reduced in recanalized patients (odds ratio, 0.24; 95% CI, 0.16 to 0.35).Rates of symptomatic hemorrhagic transformation did not differ between the 2 groups (odds ratio, 1.11; 95% CI, 0.71 to 1.74). Conclusions-Formal meta-analysis confirms a strong correlation between recanalization and outcome in acute ischemic stroke. Recanalization is strongly associated with improved functional outcomes and reduced mortality. These findings suggest that recanalization is an appropriate biomarker of therapeutic activity in early phase trials of thrombolytic treatment in acute ischemic stroke. (Stroke. 2007;38:967-973.)

Collateral state and the effect of endovascular reperfusion therapy on clinical outcome in ischemic stroke patients

“…2015a). Previous studies indicated a high predictive value of successful reperfusion (Rha and Saver 2007) and pretreatment CT‐angiographic collateral status (Miteff et al. 2009; Lima et al.…”

“…2011). Besides collateral status, recanalization is strongly associated with improved functional outcomes and reduced mortality (Rha and Saver 2007), more specifically, substantial angiographic reperfusion seems to be the best predictor for independence after 3 months (Yoo et al. 2013).…”

Thirty‐day recurrence after ischemic stroke or TIA

“…As intracranial vessels may become stenotic or occluded due to both atherosclerotic and embolic disease, we did not etiologically group them as LAA, but as a separate group. Spontaneous recanalization of emboli in the intracranial arteries will often occur, but may happen both in the acute phase and days and weeks after the initial stroke (Rha & Saver, 2007). As a result of this, it may be difficult to discriminate between LAA and CE as cause of an intracranial lesion in the first weeks and months after stroke.…”

Thrombolytic Recanalization of Carotid Arteries Is Highly Dependent on Degree of Stenosis, Despite Sonothrombolysis

“…Patients with carotid occlusion–associated stroke have high rates of death and disability but treatments are limited. Successful recanalization with intravenous tissue plasminogen activator (tPA), the current stroke thrombolytic, is only achieved in 10% to 30% of patients with carotid occlusion 1, 2, 3. Although a severe carotid stenosis predicts a greater risk of stroke for any individual,4 the population frequency of mild stenosis is greater.…”