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Acute ST-elevation myocardial infarction (STEMI) and acute ischaemic stroke (AIS) share a number of similarities. However, important differences in pathophysiology demand a disease-tailored approach. In both conditions, fast treatment plays a crucial role as ischaemia and eventually infarction develop rapidly. Furthermore, in both fields, the introduction of fibrinolytic treatments historically preceded the implementation of endovascular techniques. However, in contrast to STEMI, only a minority of AIS patients will eventually be considered eligible for reperfusion treatment. Non-invasive cerebral imaging always precedes cerebral angiography and thrombectomy, whereas coronary angiography is not routinely preceded by non-invasive cardiac imaging in patients with STEMI. In the late or unknown time window, the presence of specific patterns on brain imaging may help identify AIS patients who benefit most from reperfusion treatment. For STEMI, a uniform time window for reperfusion up to 12 h after symptom onset, based on old placebo-controlled trials, is still recommended in guidelines and generally applied. Bridging fibrinolysis preceding endovascular treatment still remains the mainstay of reperfusion treatment in AIS, while primary percutaneous coronary intervention is the strategy of choice in STEMI. Shortening ischaemic times by fine-tuning collaboration networks between ambulances, community hospitals, and tertiary care hospitals, optimizing bridging fibrinolysis, and reducing ischaemia–reperfusion injury are important topics for further research. The aim of this review is to provide insights into the common as well as diverging pathophysiology behind current reperfusion strategies and to explore new ways to enhance their clinical benefit. [ABSTRACT FROM AUTHOR]

Objective: Patients with acute ischemic stroke harboring a large vessel occlusion who present to primary stroke centers often require inter‐hospital transfer for thrombectomy. We aimed to determine clinical and imaging factors independently associated with fast infarct growth (IG) during inter‐hospital transfer. Methods: We retrospectively analyzed data from acute stroke patients with a large vessel occlusion transferred for thrombectomy from a primary stroke center to one of three French comprehensive stroke centers, with an MRI obtained at both the primary and comprehensive center before thrombectomy. Inter‐hospital IG rate was defined as the difference in infarct volumes on diffusion‐weighted imaging between the primary and comprehensive center, divided by the delay between the two MRI scans. The primary outcome was identification of fast progressors, defined as IG rate ≥5 mL/hour. The hypoperfusion intensity ratio (HIR), a surrogate marker of collateral blood flow, was automatically measured on perfusion imaging. Results: A total of 233 patients were included, of whom 27% patients were fast progressors. The percentage of fast progressors was 3% among patients with HIR < 0.40 and 71% among those with HIR ≥ 0.40. In multivariable analysis, fast progression was independently associated with HIR, intracranial carotid artery occlusion, and exclusively deep infarct location at the primary center (C‐statistic = 0.95; 95% confidence interval [CI], 0.93–0.98). IG rate was independently associated with good functional outcome (adjusted OR = 0.91; 95% CI, 0.83–0.99; P = 0.037). Interpretation: Our findings show that a HIR > 0.40 is a powerful indicator of fast inter‐hospital IG. These results have implication for neuroprotection trial design, as well as informing triage decisions at primary stroke centers. ANN NEUROL 2023;93:1117–1129 [ABSTRACT FROM AUTHOR]

Background and purpose: Sex‐based differences in acute ischemic stroke are a well‐known phenomenon. We aimed to explore these differences between women and men in the Efficacy and Safety of MRI‐Based Thrombolysis in Wake‐Up Stroke (WAKE‐UP) trial. Methods: We compared baseline demographic and imaging characteristics (visual fluid‐attenuated inversion recovery [FLAIR] positivity, relative FLAIR signal intensity, collateral status) between women and men in all screened patients. In randomized patients (i.e., those with diffusion‐weighted imaging (DWI)–FLAIR mismatch), we evaluated a modifying role of sex on the treatment effect of alteplase in multivariable logistic regression, with treatment adjusted for National Institute of Health Stroke Scale (NIHSS) score and age. Dependent variables were modified Rankin Scale (mRS) score of 0–1 at 90 days and distribution of mRS scores at 90 days. Results: Of 1362 screened patients, 529 (38.8%) were women. Women were older than men, had higher baseline NIHSS scores and smoked less frequently. FLAIR positivity of the DWI lesion was equally present in women (174/529, 33.1%) and men (273/833, 33.3%; p = 1.00) and other imaging variables also did not differ between the sexes. In a total of 503 randomized patients, of whom 178 were women (35.4%), sex did not modify the treatment effect of alteplase on mRS score 0–1 or on the total distribution of mRS scores. Conclusion: As in many other stroke trials, more men than women were included in the WAKE‐UP trial, but the presence of a visual DWI–FLAIR mismatch and the relative FLAIR signal intensity did not differ between the sexes. The treatment effect of alteplase was not modified by sex. [ABSTRACT FROM AUTHOR]

Objective: To explore the prevalence of the perfusion-weighted imaging (PWI)-diffusion-weighted imaging (DWI) mismatch and response to intravenous thrombolysis in the WAKE-UP trial.Methods: We performed a prespecified post hoc analysis of ischemic stroke patients screened for DWI-fluid-attenuated inversion recovery (FLAIR) mismatch in WAKE-UP who underwent PWI. We defined PWI-DWI mismatch as ischemic core volume < 70ml, mismatch volume > 10ml, and mismatch ratio > 1.2. Primary efficacy end point was a modified Rankin Scale score of 0-1 at 90 days, adjusted for age and symptom severity.Results: Of 1,362 magnetic resonance imaging-screened patients, 431 underwent PWI. Of these, 57 (13%) had a double mismatch, 151 (35%) only a DWI-FLAIR mismatch, and 54 (13%) only a PWI-DWI mismatch. DWI-FLAIR mismatch was more prevalent than PWI-DWI mismatch (48%, 95% confidence interval [CI] = 43-53% vs 26%, 95% CI = 22-30%; p < 0.0001). Screening for either one of the mismatch profiles resulted in a yield of 61% (95% CI = 56-65%). Prevalence of PWI-DWI mismatch was similar in patients with (27%) or without (24%) DWI-FLAIR mismatch (p = 0.52). In an exploratory analysis in the small subgroup of 208 randomized patients with PWI, PWI-DWI mismatch status did not modify the treatment response (p for interaction = 0.73).Interpretation: Evaluating both the DWI-FLAIR and PWI-DWI mismatch patterns in patients with unknown time of stroke onset will result in the highest yield of thrombolysis treatment. The treatment benefit of alteplase in patients with a DWI-FLAIR mismatch seems to be driven not merely by the presence of a PWI-DWI mismatch, although this analysis was underpowered. ANN NEUROL 2020;87:931-938. [ABSTRACT FROM AUTHOR]