Thrombolysis for Acute Wake-Up and Unclear-Onset Strokes with Alteplase at 0.6 mg/kg in Clinical Practice: THAWS2 Study.

INTRODUCTION: The aim of this study was to determine the safety and efficacy of intravenous (IV) alteplase at 0.6 mg/kg for patients with acute wake-up or unclear-onset strokes in clinical practice. METHODS: This multicenter observational study enrolled acute ischemic stroke patients with last-known-well time >4.5 h who had mismatch between DWI and FLAIR and were treated with IV alteplase. The safety outcomes were symptomatic intracranial hemorrhage (sICH) after thrombolysis, all-cause deaths, and all adverse events. The efficacy outcomes were favorable outcome defined as an mRS score of 0-1 or recovery to the same mRS score as the premorbid score, complete independence defined as an mRS score of 0-1 at 90 days, and change in NIHSS at 24 h from baseline. RESULTS: Sixty-six patients (35 females; mean age, 74 ± 11 years; premorbid complete independence, 54 [82%]; median NIHSS on admission, 11) were enrolled at 15 hospitals. Two patients (3%) had sICH. Median NIHSS changed from 11 (IQR, 6.75-16.25) at baseline to 5 (3-12.25) at 24 h after alteplase initiation (change, -4.8 ± 8.1). At discharge, 31 patients (47%) had favorable outcome and 29 (44%) had complete independence. None died within 90 days. Twenty-three (35%) also underwent mechanical thrombectomy (no sICH, NIHSS change of -8.5 ± 7.3), of whom 11 (48%) were completely independent at discharge. CONCLUSIONS: In real-world clinical practice, IV alteplase for unclear-onset stroke patients with DWI-FLAIR mismatch provided safe and efficacious outcomes comparable to those in previous trials. Additional mechanical thrombectomy was performed safely in them.

Thrombolysis With Alteplase at 0.6 mg/kg for Stroke With Unknown Time of Onset: A Randomized Controlled Trial.

Background and Purpose- We assessed whether lower-dose alteplase at 0.6 mg/kg is efficacious and safe for acute fluid-attenuated inversion recovery-negative stroke with unknown time of onset. Methods- This was an investigator-initiated, multicenter, randomized, open-label, blinded-end point trial. Patients met the standard indication criteria for intravenous thrombolysis other than a time last-known-well >4.5 hours (eg, wake-up stroke). Patients were randomly assigned (1:1) to receive alteplase at 0.6 mg/kg or standard medical treatment if magnetic resonance imaging showed acute ischemic lesion on diffusion-weighted imaging and no marked corresponding hyperintensity on fluid-attenuated inversion recovery. The primary outcome was a favorable outcome (90-day modified Rankin Scale score of 0-1). Results- Following the early stop and positive results of the WAKE-UP trial (Efficacy and Safety of MRI-Based Thrombolysis in Wake-Up Stroke), this trial was prematurely terminated with 131 of the anticipated 300 patients (55 women; mean age, 74.4±12.2 years). Favorable outcome was comparable between the alteplase group (32/68, 47.1%) and the control group (28/58, 48.3%; relative risk [RR], 0.97 [95% CI, 0.68-1.41]; P=0.892). Symptomatic intracranial hemorrhage within 22 to 36 hours occurred in 1/71 and 0/60 (RR, infinity [95% CI, 0.06 to infinity]; P>0.999), respectively. Death at 90 days occurred in 2/71 and 2/60 (RR, 0.85 [95% CI, 0.06-12.58]; P>0.999), respectively. Conclusions- No difference in favorable outcome was seen between alteplase and control groups among patients with ischemic stroke with unknown time of onset. The safety of alteplase at 0.6 mg/kg was comparable to that of standard treatment. Early study termination precludes any definitive conclusions. Registration- URL: https://www.clinicaltrials.gov; Unique identifier: NCT02002325.

Dabigatran vs. Aspirin for Secondary Prevention After Embolic Stroke of Undetermined Source　- Japanese Subanalysis of the RE-SPECT ESUS Randomized Controlled Trial.

BACKGROUND: The international Randomized, Double-Blind, Evaluation in Secondary Stroke Prevention Comparing the EfficaCy and Safety of the Oral Thrombin Inhibitor Dabigatran Etexilate versus Acetylsalicylic Acid in Patients with Embolic Stroke of Undetermined Source (RE-SPECT ESUS) trial did not demonstrate superiority of dabigatran over aspirin for reduction of recurrent strokes in patients with embolic strokes of undetermined source (ESUS). Based on pre-defined subanalyses, the safety and efficacy of dabigatran vs. aspirin in Japanese patients was assessed.Methods and Results:ESUS patients were randomized to receive either dabigatran (150 or 110 mg twice daily) or aspirin (100 mg once daily). Of 5,390 patients randomized, 594 were Japanese. Most Japanese patients (99.8%) underwent brain magnetic resonance imaging for trial screening, compared to 76.8% of non-Japanese (P<0.0001). In the Japanese cohort, over a 19.4-month median follow-up period, recurrent stroke as the primary outcome occurred in 20/294 patients (4.3%/year) in the dabigatran group and 38/300 (8.3%/year) in the aspirin group (hazard ratio [HR], 0.55; 95% confidence interval [CI], 0.32-0.94). Major bleeding occurred in 12 patients (2.5%/year) and 17 patients (3.5%/year), respectively (HR, 0.72; 95% CI, 0.34-1.52). In contrast, in the non-Japanese cohort, recurrent stroke occurred in 4.1%/year and 4.3%/year, respectively, showing no apparent difference in recurrent stroke for dabigatran vs. aspirin (HR, 0.91; 95% CI, 0.74-1.14). The P-interaction for treatment and region did not reach statistical significance (P=0.09). CONCLUSIONS: Dabigatran was putatively associated with a lower relative risk of recurrent stroke compared with aspirin in Japanese ESUS patients.

Intravenous Alteplase at 0.6 mg/kg for Unknown Onset Stroke with Prior Antithrombotic Medication: THAWS Randomized Clinical Trial.

AIM: This study aimed to assess the potential effect of prior antithrombotic medication for thrombolysis in an unknown onset stroke. METHODS: This was a predefined sub-analysis of the THAWS trial. Stroke patients with a time last known well ＞4.5 h who had a DWI-fluid-attenuated inversion recovery mismatch were randomly assigned (1:1) to receive alteplase at 0.6 mg/kg (alteplase group) or standard medical treatment (control group). Patients were dichotomized by prior antithrombotic medication. RESULTS: Of 126 patients (intention-to-treat population), 40 took antithrombotic medication (24 with antiplatelets alone, 13 with anticoagulants alone, and 3 with both), and the remaining 86 did not before stroke onset. Of these, 17 and 52 patients, respectively, received alteplase, and 23 and 34, respectively, had standard medical treatment. Antithrombotic therapy was initiated within 24 h after randomization less frequently in the alteplase group (12% vs. 86%, p＜0.01). Both any intracranial hemorrhage within 22-36 h (26% vs. 14%) and a modified Rankin Scale score of 0-1 at 90 days (good outcome) (47% vs. 48%) were comparable between the two groups. A good outcome was more common in the alteplase group than in the control group in patients with prior antithrombotic medication [relative risk (RR) 2.25, 95% confidence interval (CI) 1.02-4.99], but it tended to be less common in the alteplase group in those without (RR 0.69, 95% CI 0.46-1.03) (p＜0.01 for interaction). The frequency of any intracranial hemorrhage did not significantly differ between the two groups in any patients dichotomized by prior antithrombotic medication. CONCLUSION: Alteplase appears more beneficial in patients with prior antithrombotic medication.

[Carotid endarterectomy preceding distal plaque-end dissection followed by internal shunt insertion: a case report].

We report a case of carotid endarterectomy preceding distal plaque-end dissection followed by internal shunt insertion. A 60-year-old man was admitted to hospital with right hemiparesis. Magnetic resonance imaging detected multiple fresh infarcts in the left hemisphere, and the patient was transferred to our hospital. Angiography revealed high-grade stenosis in the left internal carotid artery at the level of the second cervical vertebra. Computed tomography angiography showed calcification in the proximal and the distal side of the stenotic lesion in the left carotid artery. The lesion was thought to be high position though an accurate assessment of the distal tip was difficult. The patient also received a blood transfusion for advanced anemia due to gross hematuria associated with bladder cancer. Carotid endarterectomy was performed one month after onset. Because atheromatous plaque had progressed far from the incision, we considered that arterial shunt insertion would induce embolic complications. Thus, we proceeded with distal plaque-end dissection, and then inserted the internal shunt and removed the plaque. This procedure resulted in successful revascularization.

[Carotid MRI of initial and recurrent plaques in patients with restenosis after endarterectomy: three case reports].

Restenosis after carotid endarterectomy (CEA) is one of most significant complications. There is no previous report about MRI findings of restenotic lesions and preoperative plaques. The purpose of this study was to evaluate the initial and recurrent plaques in patients with restenosis after CEA by using black-blood MRI (BB-MRI). Three patients who underwent carotid artery stenting for restenosis after CEA were included in this study. The relative signal intensities (rSI) of the initial and recurrent plaques were calculated with reference to the sternocleidomastoid muscle on T1-weighted images (T1WI) and the submandibular gland on T2-weighted images (T2WI). This study investigated the rSI characteristics and morphology of the initial and recurrent plaques. All patients had restenosis within 1 year after CEA. The rSI values of the preoperative lesion were not high on T1WI and were high on T2WI in all cases (T1WI/T2WI: 0.63/2.43 in Case 1, 1.00/1.29 in Case 2, and 1.13/1.70 in Case 3). The morphology of the initial plaques was eccentric in 2 cases and concentric in 1 case. The rSI values of restenosis were high on T2WI in all cases (T1WI/T2WI: 1.09/1.20 in Case 1, 1.31/1.50 in Case 2, and 1.23/1.70 in Case 3). The morphology of restenotic lesions was concentric in all cases. The high rSI on T2WI and concentricity of the restenosis after CEA suggest early restenosis (intimal hyperplasia). The low-iso rSI on T1WI and high rSI on T2WI of the preoperative plaques are associated with restenosis after CEA. BB-MRI may be useful to evaluate and predict restenosis after CEA. (Received: May 7, 2012, Accepted: September 10, 2012).