Effect of Time Window on Endovascular Thrombectomy with or without Intravenous Thrombolysis in Acute Ischemic Stroke: Results from DIRECT-MT.

INTRODUCTION: Whether time window affects the intravenous thrombolysis (IVT) effect before endovascular thrombectomy (EVT) is uncertain. We aimed to investigate the effect of different time windows (0-3 h and >3-4.5 h from stroke onset to randomization) on clinical outcomes of EVT with or without IVT in a subgroup analysis of DIRECT-MT. METHODS: The primary outcome was the 90-day modified Rankin Scale (mRS) according to time window. Logistic regression models were used to analyze the effect of different treatments (EVT with or without IVT) on outcomes within 0-3 h or >3-4.5 h. RESULTS: Among 656 patients who were included in the analysis, 282 (43.0%) were randomized within >3-4.5 h after stroke onset (125 without IVT and 157 with IVT), and 374 (57.0%) were randomized within 0-3 h (202 without IVT and 172 with IVT). We noted no significant difference in the thrombectomy-alone effect between the time window subgroups according to 90-day ordinal mRS (adjusted common odds ratio [acOR] in patients within 0-3 h: 1.06 [95% CI: 0.73-1.52], acOR in patients within >3-4.5 h: 1.19 [95% CI: 0.78-1.82]) and 90-day functional independence. Thrombectomy alone resulted in an increased proportion of patients with 90-day mRS 0-3 treated within >3-4.5 h (62.90 vs. 48.72%) but not within 0-3 h (65.84 vs. 63.95%). However, there was no interaction effect regarding all outcomes after the Bonferroni correction. CONCLUSIONS: Our results did not support thrombectomy-alone administration within 3-4.5 h in patients with acute ischemic stroke from large-vessel occlusion in the subgroup analysis of DIRECT-MT.

Cost-Effectiveness of Low-Dose Compared to Standard-Dose Alteplase for Acute Ischemic Stroke in China: A Within-Trial Economic Evaluation of the ENCHANTED Study.

INTRODUCTION: The Enhanced Control of Hypertension and Thrombolysis Stroke Study (ENCHANTED) showed that a low-dose alteplase was safe but not clearly non-inferior to standard-dose alteplase in acute ischemic stroke (AIS). Given the significant cost of this medicine, we undertook a cost-effectiveness analysis to determine the probability that low-dose is cost-effective relative to standard-dose alteplase in China. METHODS: For ENCHANTED participants in China with available health cost data, cost-effectiveness and cost-utility analyses were undertaken in which death or disability (modified Rankin scale scores 2-6) at 90 days and quality-adjusted life-years (QALYs) were used as outcome measures, respectively. There was adherence to standard guidelines for health economic evaluations alongside non-inferiority trials and according to a health-care payer's perspective. The equivalence margin for cost and effectiveness was set at USD 691 and -0.025 QALYs, respectively, for the base-case analysis. Probabilistic sensitivity analyses were used to evaluate the probability of low-dose alteplase being non-inferior. RESULTS: While the mean cost of alteplase was lower in the low-dose group (USD 1,569 vs. USD 2,154 in the standard-dose group), the total cost was USD 56 (95% confidence interval [CI]: -1,000-1,113) higher compared to the standard-dose group due to higher hospitalization costs in the low-dose group. There were 462 (95% CI: 415-509) and 410 (95% CI: 363-457) patients with death or disability per 1,000 patients in the low-dose and standard-dose groups, respectively. The low-dose group had marginally lower (0.008, 95% CI: -0.016-0.001) QALYs compared to their standard-dose counterparts. The low-dose group was found to have an 88% probability of being non-inferior based on cost-effectiveness versus the standard-dose group. CONCLUSIONS: This health economic evaluation alongside the ENCHANTED indicates that the use of low-dose alteplase does not save overall healthcare costs nor lead to a gain in QALYs in the management of Chinese patients with AIS compared to the use of standard dose. There is little justification on economic grounds to shift from standard-of-care thrombolysis in AIS.

Blood pressure excursion on admission and intravenous thrombolysis in ischemic stroke.

BACKGROUND: Blood pressure (BP) excursion on admission was common in patients with acute ischemic stroke, but its influence on thrombolysis effect was not fully evaluated. METHODS: Patients with acute ischemic stroke who received thrombolysis without subsequent thrombectomy were included. Admission BP excursion was defined as higher than 185/110 mmHg. Multivariate logistic regression analysis was used to evaluate the relationship between admission BP excursion and poor outcome as well as hemorrhage rates and mortality. Poor outcome was defined as a 90-day modified Rankin Scale score 3-6. Subgroup analysis was performed according to stroke severity, which was assessed by the National Institutes of Health Stroke Scale (NIHSS) score, and hypertension status. RESULTS: A total of 633 patients were enrolled and 240 participants (37.9%) had admission BP excursion. Admission BP excursion was associated with poor outcome [adjusted odds ratio (OR) 0.64, 95% confidence interval 0.42-0.99, P  = 0.046]. No significant difference was found regarding hemorrhage rates or mortality between patients with and without admission BP excursion. In subgroup analysis, admission BP excursion was related to poor outcome in patients with NIHSS score at least 7 (adjusted OR 1.89, 95% confidence interval 1.03-3.45, P  = 0.038), but not in patients with NIHSS score less than 7 ( P for interaction <0.001). CONCLUSION: Admission BP excursion above the guideline thresholds did not increase postthrombolysis hemorrhage risk or mortality, but was associated with poor outcome, especially in patients with severe stroke.