E-045 The time burden of CTP in late window presenters

Introduction After the DAWN and DEFUSE3 trials, CTP imaging became an integral part in the patient selection for endovascular treatment (EVT) in acute ischemic stroke (AIS) patients who present 6 to 24 hours within symptom onset. However, there is no consensus on the benefit of CTP evaluation as there is insufficient real-world data on the treatment delays CTP may pose. We highlight the time burden of CTP acquisition by investigating the time metrics and clinical outcomes of patients who were evaluated by CTP in the late time window. Methods A retrospective review of all patients who underwent EVT from January 1, 2017 to March 30, 2019 was conducted. Patients were grouped into CTP and No-CTP cohorts by whether CTP was acquired prior to EVT. Descriptive statistics and nonparametric tests were performed on dependent variables. Binomial logistic regression models with baseline predictors were run on clinical outcomes. Image acquisition time was defined as the first image to the last image acquired at the central hospital. Good outcome was defined as mRS 0–2 while bad outcome was 3–6. Results 88 patients presented 6 hours from symptom onset and underwent EVT for an anterior circulation occlusion, 75 of whom were evaluated with CTP. There was no statistically significant difference between the two cohorts’ baseline characteristics (p>0.05). Refer to table 1 for time metrics. Logistic regression models, with baseline predictors of age, gender, baseline NIHSS, ASPECTS and mRS scores, were run to assess whether CTP acquisition predicted intracerebral hemorrhage (ICH) presence and functional outcome at discharge and 90 days. CTP acquisition did not add any significant predictive value on functional outcomes at discharge (p=0.439), at 90 days (p=0.271), or on the presence of intraparenchymal hemorrhage (p=0.626). Age and baseline NIHSS significantly predicted bad outcome at discharge (Age: p=0.009, OR=1.071; NIHSS: p=0.003, OR=1.183) and 90 days (Age: p=0.012, OR=1.066; NIHSS: p=0.023, OR=1.121). A separate regression model using image acquisition time as a predictor of bad outcome at discharge showed a positive trend that did not meet significance (p=0.106, OR=1.018). Conclusion Our retrospective analysis highlights the prolonged time to treatment in late window presenters evaluated with CTP due to the additional image acquisition time which could include inter-imaging delays such as image processing and interpretation. Acquisition of CTP for patient selection for EVT is neither justified by added safety, as determined by the presence of ICH, nor better functional outcomes at discharge or 90 days. Future randomized, controlled trials should evaluate the workflow time continuum and effect on outcomes for further optimization of patient selection methods for EVT in the late time window. Disclosures K. Wu: None. A. Ouf: None. J. Mocco: None. J. Fifi: None. H. Shoirah: None.