CT perfusion predicts tissue injury in TIA and minor stroke

The Clinical Features of In-Hospital Recurrence in Acute Ischaemic Stroke Patients over Time: A Real-World Observation at a Single Center

Acute ischaemic stroke (AIS) has a high risk of recurrence, particularly in the early stage. Our study aimed to assess the clinical characteristics and risk factors of in-hospital ischaemic recurrence in AIS patients in different periods. This study was a retrospective, single-center analysis. The patients were divided into two stages based on their admission time. The primary endpoint was recurrent stroke during hospitalization. In total, 978 patients in Stage 1 and 1047 patients in Stage 2 were included in this study. The in-hospital recurrence rate in Stage 1 was 5.9%, while that in Stage 2 was 4.0% (p = 0.046). A recurrence rate reduction mainly occurred in the minor stroke and large-artery atherosclerosis (LAA) stroke patients. Infection was an independent risk factor despite amelioration by antiplatelet therapy (p < 0.001). Diabetes patients also had a higher risk of in-hospital ischaemic recurrence among the minor stroke and large-artery atherosclerosis patients. A positive attitude towards antiplatelet therapy failed to completely halt recurrence of the disease. In conclusion, the rate of in-hospital ischaemic recurrence in AIS patients showed a decreasing trend over time, especially in the minor stroke and large-artery atherosclerosis stroke patients. Infection and diabetes were associated with a higher risk of stroke recurrence.

Current aspects of TIA management

Transient Ischaemic Attack (TIA) if untreated carries a high risk of early stroke and is associated with poorer long-term survival [1]. There is emerging evidence of a reduction in stroke risk following TIA. Time critical investigations and management, as well as service organisation remain key to achieving good outcomes. Patients are diagnosed with TIA if they have transient, sudden-onset focal neurological symptoms which usually completely and rapidly resolve by presentation. The tissue based definition of TIA guides the fact that patients with residual symptoms should be considered as potentially having a stroke, with urgent evaluation regarding eligibility for thrombolysis and/or endovascular clot retrieval (ECR). Essential investigations for all patients with TIA should include early brain imaging, ECG, and carotid imaging in patients with anterior circulation symptoms. After brain imaging, exclusion of high risk indicators and immediate administration of an antiplatelet agent, subsequent attention to other mechanistic factors can be managed safely as part of a structured clinical pathway supervised by stroke specialists. This is in line with the recently revised Stroke Foundation Clinical Guidelines for Stroke Management (2017).

Perfusion computed tomography in posterior circulation stroke: predictors and prognostic implications of focal hypoperfusion

BACKGROUND AND PURPOSE

The aim was to determine the predictors of focal hypoperfusion on computed tomography (CT) perfusion (CTP) in patients with acute posterior circulation stroke and its association with long-term outcome.

METHODS

Patients with posterior circulation stroke were selected from the Acute Stroke Registry and Analysis of Lausanne (ASTRAL) who underwent CTP within 24 h of stroke onset as part of the stroke imaging protocol. Hypoperfusion was defined as an area of visually well demarcated mean transit time prolongation corresponding to an arterial territory on standard reconstruction CTP imaging maps. Areas of hypoperfusion were assessed with the posterior circulation Acute Stroke Prognosis Early CT Score. Clinical and imaging associations with focal hypoperfusion were identified using multiple imputation analyses, and the adjusted functional outcome measured by the modified Rankin Scale at 3 and 12 months was determined.

RESULTS

Of the 3595 consecutive patients from the ASTRAL registry between 2003 and 2014, 1070 (29.7%) had a posterior circulation stroke and 436 of these (40.7%) patients had a good quality baseline CTP. 23.1% had early ischaemic changes and 37.4% had focal hypoperfusion. In multiple imputation analysis, visual field deficits, reduced level of consciousness, cardiac and multiple stroke mechanisms, significant vessel pathology and ischaemic changes visible on plain CT were associated with focal hypoperfusion. Focal hypoperfusion was independently associated with outcome at 12 months (odds ratio 2.04, 95% confidence interval 1.22-3.42, P < 0.01).

CONCLUSIONS

In posterior circulation stroke patients undergoing acute CTP, multiple clinical, aetiological and radiological variables were associated with focal hypoperfusion. Patients with focal hypoperfusion had a worse 12-month outcome.