Ischemic core and hypoperfusion volumes predict infarct size in SWIFT PRIME

Abstract

Objective: Within the context of a prospective randomized trial (SWIFT PRIME), we assessed whether early imaging of stroke patients, primarily with computed tomography (CT) perfusion, can estimate the size of the irreversibly injured ischemic core and the volume of critically hypoperfused tissue. We also evaluated the accuracy of ischemic core and hypoperfusion volumes for predicting infarct volume in patients with the target mismatch profile. Methods: Baseline ischemic core and hypoperfusion volumes were assessed prior to randomized treatment with intravenous (IV) tissue plasminogen activator (tPA) alone versus IV tPA 1 endovascular therapy (Solitaire stentretriever) using RAPID automated postprocessing software. Reperfusion was assessed with angiographic Thrombolysis in Cerebral Infarction scores at the end of the procedure (endovascular group) and Tmax > 6-second volumes at 27 hours (both groups). Infarct volume was assessed at 27 hours on noncontrast CT or magnetic resonance imaging (MRI). Results: A total of 151 patients with baseline imaging with CT perfusion (79%) or multimodal MRI (21%) were included. The median baseline ischemic core volume was 6ml (interquartile range 5 0-16). Ischemic core volumes correlated with 27-hour infarct volumes in patients who achieved reperfusion (r 5 0.58, p < 0.0001). In patients who did not reperfuse (<10% reperfusion), baseline Tmax > 6-second lesion volumes correlated with 27-hour infarct volume View this article online at wileyonlinelibrary.com.

Comparison of Perfusion CT Software to Predict the Final Infarct Volume After Thrombectomy

“…Although selection of our patient population was not ideal compared with the controlled thrombectomy trials, 5,35,38 our study has the advantage of reflecting daily clinical routine better. Nevertheless, our results about predictive accuracy of FIV are in good agreement with the results in the subanalysis of SWIFT PRIME, 40,41 despite the generally longer time windows in our population. This supports the idea that CTP may have the potential to widen the individual time window beyond 6 hours for MT.…”

Automated CT Perfusion for Ischemic Core Volume Prediction in Tandem Anterior Circulation Occlusions

“…Although the most appropriate selection method for AIS thrombectomy remains elusive, the use of an automated CT perfusion (CTP) system (RAPID; iSchemaView, Inc., Menlo Park, Calif., USA) has been demonstrated to provide rapid and accurate prediction of core stroke volumes [6,7]. However, vulnerabilities inherent in the pharmacokinetic models in widespread use, particularly those related to delay/dispersion of the bolus in the tissue or arterial input, have been discussed extensively [8,9,10].…”

Ischemic core thresholds change with time to reperfusion: A case control study

“…Baseline National Institutes of Health Stroke Scale (median, 15; interquartile range [IQR], [11][12][13][14][15][16][17][18][19], age (median, 65; IQR, 59-80), and time to intravenous treatment (median, 153 minutes; IQR, 82-315) were well matched (all p > 0.05). Despite similar baseline CTP ischemic core volumes using the previously validated measure (relative cerebral blood flow [rCBF], <30%), thrombectomy patients had a smaller median 24-hour infarct core of 17.3ml (IQR, 11.3-32.8) versus 24.3ml (IQR, 16.7-42.2; p 5 0.011) in alteplase-treated controls.…”