Risk factors for infarct growth and haemorrhagic or oedematous complications after endovascular treatment — a literature review

Abstract

Introduction. Acute ischaemic stroke (AIS) is caused by significant disturbances in the cerebral bloodflow (CBF) that lead to brain ischaemia and eventually result in irreversible brain tissue damage. The main goal of its treatment is to restore bloodflow to the areas at risk of necrosis. Intravenous thrombolysis (IVT) and mechanical thrombectomy (MT) are the mainstay of current therapy, with the latter being widely employed in selected patients with radiologically proven large vessel occlusion (LVO). Despite convincing evidence of its efficacy, up to half of patients undergoing endovascular treatment (EVT) still do not achieve a beneficial functional outcome; this is mainly due to unfavourable brain tissue sequelae. Therefore, factors associated with known adverse brain changes, such as larger infarct size or haemorrhagic and oedematous complications, should be adequately addressed.Objective. To review the available literature describing AIS brain tissue outcome assessed by computed tomography (CT) and/ or magnetic resonance imaging (MRI) in patients undergoing MT treatment. Additionally, to evaluate the association of post-MT tissue changes with short-and long-term prognosis.Material and methods. We searched the PubMed, Scopus, EMBASE, and Google Scholar databases according to established criteria.Results. We found a total of 264 articles addressing the most common types of AIS tissue sequelae after EVT (i.e. MT with or without IVT as bridging therapy) by brain CT and MRI. These were: follow-up infarct volume (FIV), cerebral oedema (COD) and haemorrhagic transformation (HT). As the next step, 37 articles evaluating factors associated with defined outcomes were selected. Several non-modifiable factors such as age, comorbidities, pretreatment neurological deficit, and collateral circulation status were found to affect stroke tissue sequelae, to varying degrees. Additionally, some factors including time to treatment initiation, selection of treatment device, and periprocedural systemic blood pressure, the modification of which can potentially reduce the occurrence of an unfavourable tissue outcome, were identified. Some recently revealed biochemical and serological parameters may play a similar role.Conclusions. The identification of factors that affect post-MT ischaemic area evolution may result in studies assessing the effects of their modification, and potentially improve clinical outcomes. Modifiable parameters, including periprocedural systemic blood pressure and some biochemical factors, may be of particular importance.

Lipoprotein (a) concentration as a risk factor for ischaemic stroke and its subtypes

“…The undetermined subtype of IS was not associated with any significant risk factor. Diabetes, total cholesterol, and triglycerides are important modifiable risk factors for ischaemic stroke [34][35][36]. We found an increased risk for IS (OR 3.29) but with borderline significance (p = 0.07).…”

Predictors of good functional outcome in ischaemic stroke patients without delayed neurological improvement after mechanical thrombectomy

“…Importantly, we did not obtain data regarding some MTrelated complications, such as malignant cerebral oedema and infarct volume progression -both of which have been closely linked to patient prognosis [33]. Desai et al [15] showed that lower follow-up infarct volume does indeed portend delayed functional independence; we could not collect data to confirm this finding in our study, because infarct assessment was made on admission only -it was not associated with DNI.…”

Association between Transient-Continuous Hypotension during Mechanical Thrombectomy for Acute Ischemic Stroke and Final Infarct Volume in Patients with Proximal Anterior Circulation Large Vessel Occlusion

“…Despite nearly 90% successful reperfusion rates using modern stent retriever and aspiration devices, only half of the patients undergoing endovascular treatment (EVT) achieve functional independence [2]. Several factors affecting MT outcomes have been identified, with periprocedural hemodynamic parameters being of clinical importance due to their modifiable character [3]. Numerous studies have shown blood pressure (BP) variability, including intraprocedural hypotension, to be an independent risk factor for unfavorable clinical outcomes [4][5][6].…”