Monthly Archives: February 2018

Pouya Tahsili-Fahadan, MD

Nogueira RG, Jadhav AP, Haussen DC, Bonafe A, Budzik RF, Bhuva P, et al. Thrombectomy 6 to 24 Hours after Stroke with a Mismatch between Deficit and Infarct. N Engl J Med. 2018

The introduction of endovascular thrombectomy (EVT) has revolutionized acute treatment of stroke due to a large vessel occlusion (LVO). However, patients who present after 6 hours from stroke onset (defined by previous EVT trials; 7.3 hours based on a recent meta-analysis) are not eligible for either IV thrombolysis or EVT. Salvageable brain tissue that can be saved by cerebral reperfusion may exist well beyond this treatment window.

The DAWN (“DWI or CTP Assessment with Clinical Mismatch in the Triage of Wake-Up and Late Presenting Strokes Undergoing Neurointervention with Trevo”) trial studied this very population of patients. In this multi-center, prospective, randomized, open-label trial, “EVT+standard medical care” (EVT group) was compared with “standard medical care alone” (control group) in treatment of patients who presented with acute ischemic stroke due to a large vessel occlusion (LVO) within 6-24 hours from their last known well (LKW) and showed evidence of salvageable brain tissue. Presence of salvageable brain tissue was based on a mismatch between severity of their neurological deficits and the volume of infarcted brain on presentation as follows:

Data derived from Nogueira RG, Jadhav AP, Haussen DC, Bonafe A, Budzik RF, Bhuva P, et al. Thrombectomy 6 to 24 Hours after Stroke with a Mismatch between Deficit and Infarct. N Engl J Med. 2018

Enrolled patients had good pre-stroke baseline defined as modified Rankin scale, mRS, 0 to 1. Infarct volume was assessed on diffusion-weighted imaging (DWI) sequence of brain MRI or perfusion CT scan using the automated RAPID software.

Aristeidis H. Katsanos, MD

Albers GW, Marks MP, Kemp S, Christensen S, Tsai JP, Ortega-Gutierrez S, et al. Thrombectomy for Stroke at 6 to 16 Hours with Selection by Perfusion Imaging. N Engl J Med. 2018

Endovascular Therapy Following Imaging Evaluation for Ischemic Stroke 3 (DEFUSE 3) is a prospective, randomized, open-label trial with blinded outcome assessment (PROBE) comparing conventional treatment (standard medical therapy) to thrombectomy plus standard medical therapy in patients with proximal middle-cerebral-artery or internal-carotid-artery occlusion, baseline infarct size of less than 70 ml and a ratio of ischemic tissue to infarct volume more than 1.8, presenting 6 to 16 hours after they were last known to be well. The trial was prematurely terminated for efficacy after recruitment of less than half of the initially estimated sample size.

Deepak Gulati, MD

Meyer IA, Cereda CW, Correia PN, Zerlauth JP, Puccinelli F, Rotzinger DC, et al. Factors Associated With Focal Computed Tomographic Perfusion Abnormalities in Supratentorial Transient Ischemic Attacks. Stroke. 2017

TIAs are associated with an increased risk of debilitating recurrent stroke along with increased risk for cardiovascular morbidity and mortality. Several studies have demonstrated poor agreement regarding TIA diagnosis among Emergency Department (ED) physicians, neurologists, and even stroke specialists. Although many biomarkers for TIA diagnosis are promising, none has been proven to be sufficiently reliable for diagnosis of TIA. Substantial international variation exists in clinical practice and policies for hospital admission for patients with TIA. International guidelines also differ in their recommendations for brain and vascular imaging after TIA, with imaging either immediately or several days after symptom onset, and brain imaging by either CT or MRI recommended. It has been reported that CTP shows focal perfusion deficits in up to a third of suspected patients with TIA and could also predict functional outcome at 3 months. It has been shown that limiting urgent assessment to patients with a score of 4 or more on ABCD2 would miss approximately 20% of those with early recurrent strokes. There appears to be a need for more research focus on dynamic imaging modalities like CTP or MRP, in addition to clinical information for better diagnosis and management of TIA.