Does Intravenous Thrombolysis Within 4.5 to 9 Hours Increase Clot Migration Leading to Endovascular Inaccessibility?

Clot migration in patients treated with tenecteplase versus alteplase before mechanical thrombectomy

INTRODUCTION

This study aimed to describe and analyze the rate of clot migration of vessel thrombosis to distal segments in patients with acute ischemic stroke (AIS) who received intravenous thrombolysis (IVT) with tenecteplase (TNK) and alteplase (ALT) before mechanical thrombectomy (MT). In addition, we aimed to determine the relationship between thrombus migration and functional prognosis.

METHODS

This study followed the STROBE reporting guidelines. We performed a retrospective analysis of a series of patients from November 2017 to April 2023 with an AIS with thrombosis on CT imaging, treated with IVT (TNK or ALT, split into two distinct groups) prior to mechanical thrombectomy.

RESULTS

Two hundred and fifty-six patients with large vessel occlusion (LVO) were included. Ninety-six had received TNK. One hundred and sixty had received ALT. Of the 96 TNK patients, 25 experienced either complete recanalization (n = 3) or thrombus migration (n = 22). Of the 160 ALT patients, 20 experienced either complete recanalization (n = 6) or thrombus migration (n = 14). The difference being statistically substantial for the thrombus migration rate (OR = 3.61, 95% confidence interval: 1.63; 7.98). Migration to an irretrievable very distal segment occurred in four (4%) patients with TNK and in three patients (2%) with ALT (p > 0.05). Thrombus migration was not significantly associated to a different functional prognosis, measured through Rankin scale after 3 months (OR = 0.44, 95% confidence interval: 0.17; 1.12).

CONCLUSION

The use of TNK over ALT as a fibrinolytic agent is associated with a higher thrombus migration rate. The migration of thrombi to distal segments, which are theoretically less accessible for mechanical thrombectomy, did not result in worse clinical outcomes.

Acute ischaemic stroke: recent advances in reperfusion treatment

During the last 5–7 years, tremendous progress was achieved in the reperfusion treatment of acute ischaemic stroke during its first few hours from symptom onset. This review summarizes the latest evidence from randomized clinical trials and prospective registries with a focus on endovascular treatment using stent retrievers, aspiration catheters, thrombolytics, and (in selected patients) carotid stenting. Novel approaches in prehospital (mobile interventional stroke teams) and early hospital (direct transfer to angiography) management are described, and future perspectives (‘all-in-one’ laboratories with angiography and computed tomography integrated) are discussed. There is reasonable chance for patients with moderate-to-severe acute ischaemic stroke to survive without permanent sequelae when the large-vessel occlusion is removed by means of modern pharmaco-mechanic approach. Catheter thrombectomy is now the golden standard of acute stroke treatment. The role of cardiologists in stroke is expanding from diagnostic help (to reveal the cause of stroke) to acute therapy in those regions where such up-to-date Class I. A treatment is not yet available.

Clot evaluation and distal embolization risk during mechanical thrombectomy in anterior circulation stroke

INTRODUCTION

Clot features along with patients' clinical features may influence thrombus compactness predisposing at distal embolization during thrombectomy. The aim of this study was to evaluate thrombus features assessed by radiological and histopathological analysis along with patient-related features to predict distal embolization during thrombectomy.

METHODS

We performed a retrospective analysis of a prospectively maintained dataset of a tertiary stroke center inclusive of all cases of endovascular treatment for acute ischemic stroke involving anterior circulation occlusion. All patients underwent head and neck CT-angiography (CTA) at baseline. Patients were enrolled if thrombus material was suitable for histopathologic analyses.

RESULTS

A total of 327 patients underwent mechanical thrombectomy between March 2017 and May 2020. Among them, 133 (40.7%) had thrombus material suitable for histopathological analysis but 11 patients were excluded due to posterior circulation occlusion. A total of 122 patients were included in the analysis. A distal embolism was documented in 27 patients (28.4%). Multivariable analysis with distal embolism as dependent variable showed an adjusted OR of 2.64 (95%CI: 0.9-7.73; p-value: 0.08) for anticoagulant therapy, an adjusted OR of 1.38 (95%CI: 1.01-1.91; p-value 0.05) each 5-mm increasing of thrombus length at CTA. No association was found with age, sex, thrombolysis and first thrombectomy technique used.

CONCLUSION

The combined effect of anticoagulant therapy and thrombus length may have a potentially harmful effect on reperfusion during mechanical recanalization, causing distal embolization and this aspect should be taken into account in patient's risk assessment and when planning treatment strategy.

Acute reperfusion therapies for acute ischemic stroke patients with unknown time of symptom onset or in extended time windows: an individualized approach

Recent randomized controlled clinical trials (RCTs) have revolutionized acute ischemic stroke care by extending the use of intravenous thrombolysis and endovascular reperfusion therapies in time windows that have been originally considered futile or even unsafe. Both systemic and endovascular reperfusion therapies have been shown to improve outcome in patients with wake-up strokes or symptom onset beyond 4.5 h for intravenous thrombolysis and beyond 6 h for endovascular treatment; however, they require advanced neuroimaging to select stroke patients safely. Experts have proposed simpler imaging algorithms but high-quality data on safety and efficacy are currently missing. RCTs used diverse imaging and clinical inclusion criteria for patient selection during the dawn of this novel stroke treatment paradigm. After taking into consideration the dismal prognosis of nonrecanalized ischemic stroke patients and the substantial clinical benefit of reperfusion therapies in selected late presenters, we propose rescue reperfusion therapies for acute ischemic stroke patients not fulfilling all clinical and imaging inclusion criteria as an option in a subgroup of patients with clinical and radiological profiles suggesting low risk for complications, notably hemorrhagic transformation as well as local or remote parenchymal hemorrhage. Incorporating new data to treatment algorithms may seem perplexing to stroke physicians, since treatment and imaging capabilities of each stroke center may dictate diverse treatment pathways. This narrative review will summarize current data that will assist clinicians in the selection of those late presenters that will most likely benefit from acute reperfusion therapies. Different treatment algorithms are provided according to available neuroimaging and endovascular treatment capabilities.