Introduction
stroke, vessel occlusion, acute ischemic stroke, AIS
REGRESSION, STROKE, INTERACTION
Several acute ischemic stroke mechanisms that cause lesion growth continue after treatment which is detrimental to long-term clinical outcome. The potential role of intravenous alteplase treatment (IVT), a standard in stroke care, in cessing the physiological processes causing post-treatment lesion development is understudied. We analyzed patients from the MR CLEAN-NO IV trial with good quality 24-hour and 1-week follow-up Non-Contrast CT scans. We delineated hypo- and hyper-dense regions on the scans as lesion. We performed univariable logistic and linear regression to estimate the influence of IVT on the presence (growth > 0 ml) and extent of late lesion growth. The association between late lesion growth and mRS was assessed using ordinal logistic regression. Interaction analysis was performed to evaluate the influence of IVT on this association. Of the 63/116 were randomized to included patients, IVT. Median growth was 8.4(−0.88–26) ml. IVT was not significantly associated with the presence (OR: 1.24 (0.57–2.74, p = 0.59) or extent (β = 5.1(−8.8–19), p = 0.47) of growth. Late lesion growth was associated with worse clinical outcome (aOR: 0.85(0.76–0.95), p < 0.01; per 10 ml). IVT did not influence this association (p = 0.18). We did not find evidence that IVT influences late lesion growth or the relationship between growth and worse clinical outcome. Therapies to reduce lesion development are necessary.Ischemic lesions do not stabilize even after treatment of acute ischemic stroke (AIS) either with intravenous alteplase treatment (IVT) or with endovascular treatment (EVT). It has been shown that ischemic lesions may continue to evolve at least between 24 hours and 1 week after the onset of AIS.The current standard of care for treating AIS due to a large vessel occlusion consists of the IVT followed by endovascular treatment (EVT).The aim of this study was to evaluate the influence of IVT on late lesion growth between 24 hours and 1 week after onset of an AIS due to a large vessel occlusion in the anterior circulation in patients treated with EVT. Furthermore, we aimed to validate the previously shown association between late lesion growth and outcome after 90 days on our study population and assess influence of IVT on this association.