Multimode computed tomography evaluation of the efficacy and safety of an extended thrombolysis time window (3–9 hours) for acute ischemic stroke: study protocol for a retrospective clinical trial based on medical records

Abstract

Background and objectives: Intravenous thrombolysis with recombinant tissue plasminogen activator within 3 hours of acute ischemic stroke onset can reduce the risk of death and severe disability. There are differences in collateral circulation, the compensatory ability of cerebral blood vessels, and brain metabolism between each patient, leading to differences in the thrombolysis time window. Thrombolysis is considered effective in patients 3 hours after onset; however, it remains controversial whether this time window should be extended. Therefore, we will employ a retrospective case analysis study using multimode computed tomography (CT) to observe the extended time window (3–9 hours after stroke onset) and to summarize its efficacy and safety in the treatment of acute ischemic stroke. Design: This is a retrospective, single-center, case-analysis clinical trial. Methods: We will retrospectively collect data from 450 patients with acute ischemic stroke who have undergone thrombolytic therapy in the Third People's Hospital of Dalian, China, from June 2008 to December 2017. The time window will be set to 3–9 hours after stroke onset. We will evaluate the effect of this extended thrombolysis time window using multimode CT. Outcome measures: The primary outcome measure is the National Institutes of Health Stroke Scale (NIHSS) score 7 days after treatment or at discharge, to evaluate the effect of thrombolysis. The secondary outcome measures are as follows: the occurrence of hemorrhagic events 24–36 hours and 7 days after treatment; NIHSS score at 2 and 24–36 hours, and at 3 and 12 months after treatment; modified Rankin scale score at 7 days after treatment or discharge, and at 3 and 12 months after treatment; vascular stenosis and infarct size 24–36 hours and 7 days after treatment; incidence of adverse reactions and deaths at 3 months after treatment; incidence of symptomatic intracranial hemorrhagic transformation during hospitalization; vital signs and laboratory measurements (blood indexes, blood glucose, blood lipids, liver and kidney functions, myocardial enzymes, blood electrolytes, and coagulation function); and electrocardiography results. Discussion: Under the guidance of multimode CT, we will extend the thrombolysis time window to 9 hours after the onset of the disease, and summarize the efficacy and adverse reactions of an extended time window for intravenous thrombolysis after acute ischemic stroke. This trial will provide objective data for the optimization of clinical diagnoses and treatment pathways for patients. Ethics and dissemination: This trial has been approved by the Medical Ethics Committee of The Third People's Hospital of Dalian, China on December 5, 2017. The study protocol will be conducted in accordance with the Declaration of Helsinki, formulated by the World Medical Association. This trial was designed in October 2017. Data collection has begun in January 2018 and will finish in October 2018. Outcome measures will be analyzed in December 2018. The results of the trial will be reported in a scientific conference or disseminated in a peer-reviewed journal. Trial registration: This trial had been registered in the Chinese Clinical Trial Registry (registration number: ChiCTR1800014368). Protocol version (1.0).