<figure class="wp-block-audio"></figure>

1. Dittrich TD, Sporns PB, Kriemler LF, et al. Mechanical Thrombectomy Versus Best Medical Treatment in the Late Time Window in Non-DEFUSE-Non-DAWN Patients: A Multicenter Cohort Study. Stroke. 2023;54(3):722-730. doi:10.1161/STROKEAHA.122.039793

The authors assessed the efficacy and safety of mechanical thrombectomy (MT) in adult stroke patients with anterior circulation large vessel occlusion presenting in the late time window not fulfilling the DEFUSE-3 (Thrombectomy for Stroke at 6 to 16 Hours With Selection by Perfusion Imaging trial) and DAWN (Thrombectomy 6 to 24 Hours After Stroke With a Mismatch Between Deficit and Infarct trial) inclusion criteria. This was a cohort study of adults with anterior circulation large vessel occlusion admitted between 6 and 24 hours after last-seen-well at 5 participating Swiss stroke centers between 2014 and 2021. Mismatch was assessed by CT or MR perfusion with automated software (RAPID or OLEA). They excluded patients meeting DEFUSE-3 and DAWN inclusion criteria and compared those who underwent MT with those receiving best medical treatment alone by inverse probability of treatment weighting using the propensity score. The primary efficacy end point was a favorable functional outcome at 90 days, defined as a modified Rankin Scale score shift toward lower categories. The primary safety end point was symptomatic intracranial hemorrhage within 7 days of stroke onset; the secondary was all-cause mortality within 90 days.

Among 278 patients with anterior circulation large vessel occlusion presenting in the late time window, 190 (68%) did not meet the DEFUSE-3 and DAWN inclusion criteria and thus were included in the analyses. Of those, 102 (54%) received MT. In the inverse probability of treatment weighting analysis, patients in the MT group had higher odds of favorable outcomes compared with the best medical treatment alone group (modified Rankin Scale shift: acOR, 1.46) and lower odds of all-cause mortality within 90 days (aOR, 0.59). There were no significant differences in symptomatic intracranial hemorrhage (MT versus best medical treatment alone: 5% versus 2%, P=0.63).

They conclude that two out of 3 patients with anterior circulation large vessel occlusion presenting in the late time window did not meet the DEFUSE-3 and DAWN inclusion criteria. In these patients, MT was associated with higher odds of favorable functional outcomes without increased rates of symptomatic intracranial hemorrhage. These findings support the enrollment of patients into ongoing randomized trials on MT in the late window with more permissive inclusion criteria.

Both DEFUSE-3 and DAWN trials had very restrictive inclusion criteria. In this MT group, the main reasons for DEFUSE-3 ineligibility were distal occlusion site (ie, isolated occlusion of the M2 segment), low baseline NIHSS score (ie, <6 points), premorbid functional disability (ie, mRS score >2 points), and treatment with intravenous tissue-type plasminogen activator >4.5 hours after last known-well. Main reasons for DAWN ineligibility were the absence of clinical-imaging-mismatch, low baseline NIHSS score (ie, <10 points), and premorbid functional disability (ie, mRS score >1 point).

2 figures, 4 tables

2. Puetz V, Lutsep HL, Nguyen TN. Endovascular Therapy for Basilar Artery Occlusion: Among the First to Conceptualize, Last to Prove. Stroke. 2023;(March):905-908. doi:10.1161/strokeaha.122.041645

Nice summary of the current state of endovascular therapy for BAO.

The BASICS (Basilar Artery International Cooperation Study) and BEST (Basilar Artery Occlusion: Endovascular Interventions vs Standard Medical Treatment) trials were 2 seminal randomized trials comparing EVT to best medical management (BMM) in patients with BAO presenting up to the 6 and 8 hour window of estimated time of BAO. Both trials were neutral in demonstrating superiority of EVT for BAO despite a direction of treatment effect in favor of EVT.  Several concepts emerged from the BASICS trial in the selection of BAO patients that now define the care and benchmark for future study. In contrast to the traditional concept of time since last known well in the acLVO trials, the BASICS registry and BASICS trial defined the notion of estimated time of onset. Patients who had transient or minor neurological symptoms prior to the estimated time of acute BAO could be candidate for intravenous thrombolysis (IVT) and enrollment in the BASICS trial, hence broadening inclusion of patients who may have otherwise been excluded. We also learned from BASICS that patients with minor deficits, defined as a NIHSS score below 10, had equivocal outcomes of EVT compared to BMM.

ATTENTION (Endovascular Treatment for Acute Basilar-Artery Occlusion) was a randomized trial comparing endovascular versus best medical management in patients with BAO presenting within 12 hours of estimated time of BAO, with moderate to severe symptoms as defined by NIHSS score ≥10, and posterior circulation Acute Stroke Prognosis Early CT Score (pc-ASPECTS) ≥6. (pc-ASPECTS reference -https://doi.org/10.1161/STROKEAHA.107.511162). The primary end point of good functional outcome defined as modified Rankin Scale score 0 to 3 was 2-fold greater in the EVT compared to MM group.

BAOCHE (Basilar Artery Occlusion Chinese Endovascular) was a randomized trial also comparing EVT versus best medical management in patients with BAO presenting from 6 to 24 hours since symptom onset, NIHSS score ≥6, and pc-ASPECTS ≥6. As the enrollment window was extended, approximately 18% of patients received IVT. The trial was halted after interim analysis demonstrated a nearly 2-fold greater proportion of patients achieving the primary outcome (modified Rankin Scale score 0 to 3) in the EVT compared to MM group.

The “good-scan-occlusion” paradigm, which has been applied in the acLVO EVT trials by selection of patients based on the detection of an acLVO and an ASPECTS score of 5 to 6 or above, has now been shown to work for identifying patients with BAO who benefit from EVT. ATTENTION and BAOCHE were the first BAO trials which applied imaging scores, including pc-ASPECTS ≥6 and the pons-midbrain index. The good news is that in patients with BAO, this principle works for late-window patients until 24 hours without requiring advanced imaging.

3. Chandra R, Saini HS, Palmer KN, Cerejo R. The link between reversible cerebral vasoconstriction syndrome and transient global amnesia. Headache: The Journal of Head and Face Pain. 2023;63(1):168-172. doi:10.1111/head.14432

RCVS is a cerebrovascular phenomenon that presents clinically as recurrent TCHs predominantly affecting females. Although RCVS is a self-limited entity, significant complications of subarachnoid hemorrhage, cerebral infarction and seizures have been reported leading to disability and poor functional outcomes. According to recent literature, the frequency of TCH is the most predictive diagnostic factor for RCVS with a sensitivity and specificity of 74% and 98%, respectively. Definite TGA is characterized by a sudden onset of anterograde amnesia without clouding or loss of consciousness, lack of epileptic features, head trauma and focal neurologic deficits witnessed by a reliable observer during the attack, furthermore the amnestic event must resolve within 24 h. RCVS and TGA are rare disorders with an annual incidence of three and 3–10 cases per million, respectively, in the general population. The patient described in this case was given an RCVS2 score of 8 (recurrent TCH, vasoconstrictive trigger present) indicating sensitivity and specificity of 90% and 99%, respectively for diagnosis of RCVS. He also met the criteria for definite TGA as he had witnessed clear anterograde amnesia during the attack without head trauma, epileptic features, and focal neurologic deficits with resolution of amnesia within 12 h from onset. Interestingly, the MRI findings in this patient correlated with symptom onset in that it suggested an acute/subacute timeframe. Given the chronology of events that led to the patient’s hospital admission, it is likely that RCVS led to his presentation of TGA. RCVS and TGA are two acute and reversible intra-cerebral conditions whose coexistence has been reported in a total of six cases worldwide (see table). The authors report the seventh case, linking RCVS to TGA and propose a common pathophysiologic link.

1 table, 1 figure

4. Gilligan M, McGuigan C, McKeon A. Paraneoplastic Neurologic Disorders. Curr Neurol Neurosci Rep. 2023;(January). doi:10.1007/s11910-023-01250-w

Paraneoplastic neurologic disorders are heterogeneous autoimmune diseases occurring in the context of a non-nervous system cancer (solid organ or hematologic). They can arise as the clinical presentation for a previously undiagnosed cancer (e.g., a woman who presents with ataxia in whom ovarian adenocarcinoma is subsequently detected). Paraneoplastic neurological disorders can also arise during treatment for a recently diagnosed cancer, or can be the clinical presentation alerting the treating providers to a cancer relapse. These disorders can target any part of the neuraxis, rostrocaudally, from cerebral cortex to neuromuscular junction, though certain classical syndromes, now known as “high risk phenotypes,” have the highest risk for accompanying cancer (Limbic encephalitis, Encephalomyelitis, Rapidly progressive cerebellar syndrome, Subacute sensory neuronopathy, Gastro-intestinal pseudo-obstruction, Lambert Eaton myasthenic syndrome, Opsoclonus myoclonus, Dermatomyositis).