Reperfusion therapies in patients with acute ischaemic stroke and atrial fibrillation: data on safety and effectiveness from a multi-centre cohort study.

BACKGROUND: Intravenous thrombolysis (IVT) and/or endovascular therapy (EVT) are currently considered best practices in acute stroke patients. Data regarding the efficacy and safety of reperfusion therapies in patients with atrial fibrillation (AF) are conflicting as regards haemorrhagic transformation, mortality, and functional outcome. This study sought to investigate for any differences, in terms of safety and effectiveness, between AF patients with acute ischaemic stroke (AIS) treated and untreated with reperfusion therapies. METHODS: Data from two multicenter cohort studies (RAF and RAF-NOACs) on consecutive patients with AF and AIS were analyzed to compare patients treated and not treated with reperfusion therapies (IVT and/or EVT). Multivariable logistic regression analysis was performed to identify independent predictors for outcome events: 90-day good functional outcome and mortality. A propensity score matching (PSM) analysis compared treated and untreated patients. RESULTS: Overall, 441 (25.4%) were included in the reperfusion-treated group and 1,295 (74.6%) in the untreated group. The multivariable model suggested that reperfusion therapies were significantly associated with good functional outcome. Rates of mortality and disability were higher in patients not treated, especially in the case of higher NIHSS scores. In the PSM comparison, 173/250 patients (69.2%) who had received reperfusion therapies had good functional outcome at 90 days, compared to 146/250 (58.4%) untreated patients (p = 0.009, OR: 1.60, 95% CI:1.11-2.31). CONCLUSIONS: Patients with AF and AIS treated with reperfusion therapies had a significantly higher rate of good functional outcome and lower rates of mortality compared to those patients with AF and AIS who had undergone conservative treatment.

Validation of an automated ASPECTS method on non-contrast computed tomography scans of acute ischemic stroke patients.

BACKGROUND: The Alberta Stroke Program Early CT Score (ASPECTS) is a systematic method of assessing the extent of early ischemic change on non-contrast computed tomography in patients with acute ischemic stroke. Our objective was to validate an automated ASPECTS scoring method we recently developed on a large data set. MATERIALS AND METHODS: We retrospectively collected 602 acute ischemic stroke patients' non-contrast computed tomography scans. Expert ASPECTS readings on non-contrast computed tomography were compared to automated ASPECTS. Statistical analyses on the total ASPECTS, region level ASPECTS, and dichotomized ASPECTS (≤4 vs. >4) score were conducted. RESULTS: In total, 602 scans were evaluated and 6020 (602 × 10) ASPECTS regions were scored. Median time from stroke onset to computed tomography was 114 min (interquartile range: 73-183 min). Total ASPECTS for the 602 patients generated by the automated method agreed well with expert readings (intraclass correlation coefficient): 0.65 (95% confidence interval (CI): 0.60-0.69). Region level analysis showed that the automated method yielded accuracy of 81.25%, sensitivity of 61.13% (95% CI: 58.4%-63.8%), specificity of 86.56% (95% CI: 85.6%-87.5%), and area under curve of 0.74 (95% CI: 0.73-0.75). For dichotomized ASPECTS (≤4 vs. >4), the automated method demonstrated sensitivity 97.21% (95% CI: 95.4%-98.4%), specificity 57.81% (95% CI: 44.8%-70.1%), accuracy 93.02%, and area under the curve of 0.78 (95% CI: 0.74-0.81). For each individual region (M1-6, lentiform, insula, and caudate), the automated method demonstrated acceptable performance. CONCLUSION: The automated system we developed approached the stroke expert in performance when scoring ASPECTS on non-contrast computed tomography scans of acute ischemic stroke patients.

Anterior temporal artery sign in CT angiography predicts reduced fatal brain edema and mortality in acute M1 middle cerebral artery occlusions.

BACKGROUND: Mortality in acute ischemic middle cerebral artery (MCA) stroke ranges from 5% to 45%. We identify a vascular imaging sign, presence of "prominent anterior temporal artery" on computed tomography (CT) angiography (CTA) and investigate whether it predicts mortality in acute M1-MCA occlusions. METHODS: One hundred and two patients with acute M1-MCA occlusions from 2003-to 2007 were included in the study. A prominent anterior temporal artery arising from proximal M1 MCA was identified by two readers blinded to clinical outcome. Primary clinical outcome was survival (modified Rankin Scale [mRS] 0-5) at 3 months. RESULTS: An anterior temporal artery arising from M1 MCA was present in 20/102 (20%). Eighteen of 20 (90%) patients with this sign survived at 3 months (mRS 0-5) when compared to 66/82 (80.4%) patients without the sign (odds ratio 2.2 CI(95) .5-10.4). The sign has a sensitivity of 21% (CI(95) .13-.25) but specificity of 89% (CI(95) .64-.98) in predicting survival at 3 months. Positive predictive value was 90% with likelihood ratio of 1.9 (CI(95) .9-7.6). CONCLUSION: Presence of prominent anterior temporal artery in M1-MCA occlusions on CTA identifies a group of patients with reduced case fatality. The mechanism is likely related to a reduced chance of malignant cerebral edema.