Outcomes and CT Perfusion Thresholds of Mechanical Thrombectomy for Patients With Large Ischemic Core Lesions

Effect of intravenous thrombolysis before endovascular therapy on outcomes in acute ischemic stroke with large core: a systematic review and meta-analysis

OBJECTIVE

To investigate the effect of intravenous thrombolysis (IVT) before endovascular therapy (EVT) on outcomes in acute ischemic stroke of large core.

METHODS

The studies comparing functional outcomes after EVT with and without IVT were systematically searched up to October 10th, 2023. Odds ratio (OR) was pooled using random effects model. Subgroup analysis was performed stratified by study design, country or region, study date, imaging methods and time window.

RESULTS

Thirteen studies were included, enrolling 1717 patients. The pooled rate of functional independence in patients receiving IVT + EVT was 26% (95% CI 20% - 33%), significantly higher than 18% (95% CI 15% - 20%) in those receiving EVT alone (OR 1.55, 95% CI 1.13-2.12, P = 0.006; I²= 23.9%). In subgroup analysis, prior IVT increased the probability of functional independence in retrospective studies (OR 1.97, 95% 1.47-2.63, P < 0.00001; I2 = 0). Non-Asian patients benefit from IVT before EVT for functional independence (OR 2.04, 95% 1.48-2.81, P < 0.0001; I2 = 0), but Asian patients did not (OR 1.45, 95% 0.90-2.35, p = 0.13; I2 = 0). The pooled rate of symptomatic intracranial hemorrhage in patients receiving IVT + EVT was 16% (95% CI 12% - 20%), inclining to be higher than 11% (95% CI 6% - 15%) in those receiving EVT alone without significant difference (OR 1.42, 0.83-2.41, P = 0.20; I²= 12%).

CONCLUSIONS

IVT before EVT might increase the probability of functional independence in non-Asian patients with large ischemic core. The results provided clinicians with additional information on selecting eligible patients for EVT.

Predictive Value of Acute Neurological Progression Using Bayesian CT Perfusion for Acute Ischemic Stroke with Large or Median Vessel Occlusion

Objective

Since the efficacy of mechanical thrombectomy (MT) for acute cerebral infarction due to large vessel occlusion has been proven, the time available for treatment has gradually increased. Currently, under certain conditions, treatment is indicated up to 24 h from onset. Based on neurological signs and imaging diagnosis, Stroke Treatment Guideline 2021 recommends initiation of MT within 6-24 h from onset. Herein, we retrospectively investigated the relationship between cerebral perfusion imaging evaluation and prognosis in patients with acute cerebral infarction due to large or median vessel occlusion.

Methods

Fifty-one patients diagnosed with acute cerebral infarction due to large or median vessel occlusions in anterior circulation between November 2019 and December 2021 were divided into medical care and reconstructive therapy (including tissue plasminogen activator [t-PA] therapy and MT) groups. The primary outcome was changes in the National Institutes of Health Stroke Scale (NIHSS) at admission and 1 week after onset. Patients in the medical care group were divided into those whose NIHSS did not worsen and those whose NIHSS worsened. Those in the reconstructive therapy group were divided into those whose NIHSS improved and those whose NIHSS did not improve. We evaluated the relationship between improvement factors in acute neurological symptoms and penumbral and core volumes from computed tomography perfusion performed at admission.

Results

Of 45 eligible patients, 10 received medical care without t-PA or MT and 35 underwent reconstructive therapy, including t-PA and MT. Among the 10 patients in the medical care group, 3 had worsening symptoms and 7 did not. The mean and median (interquartile range [IQR]) penumbra volumes were significantly higher in patients with worsening symptoms than in those without. The receiver operating characteristic (ROC) curve showed a threshold value of 28.6 mL with an area under the curve (AUC) of 0.952. Among the 35 patients in the reconstructive therapy group, symptoms improved for 29 but did not improve for 6. The mean and median (IQR) core volumes were significantly higher in patients whose symptoms did not improve than in those whose symptoms improved. The ROC curve showed a threshold value of 25 mL and an AUC of 0.632.

Conclusion

Evaluation of penumbra volumes could detect cases with worsening symptoms in cases where medical care was performed, and evaluation of core volumes may detect cases with non-improved symptoms in cases that received reconstructive therapy.