The prognostic significance of large vessel occlusion in stroke patients treated by intravenous thrombolysis

Introduction
According to guidelines, to shorten the treatment window, acute ischaemic stroke (AIS) treatment by intravenous thrombolysis (IVT) can be done based on the results of head computed tomography (CT) without contrast. The impact of large vessel occlusion (LVO) on computed tomography angiography (CTA) in stroke prognosis in patients treated IVT or IVT and mechanical thrombectomy (MT), where indicated, has not yet been studied systema­tically. We investigated the influence of LVO in consecutive AIS patients on haemorrhagic transformation (HT) on CT 24 h after treatment, mRS < 2 on discharge (unfavourable outcome), and in-hospital mortality.

Material and methods
We analysed several parameters within 24 h after AIS: demographics, risk factors, mRS score pre-stroke, NIHSS upon admission and 24 h later, several clinical and biochemical parameters, and chronic treatment.

Results
We registered 1209 patients, of whom 362 (29.9%) received IVT and 108 had MT, where indicated. Admission CTA showed LVO in 197 patients (54.4%). Multivariate regression analysis showed that the presence of LVO and lower delta NIHSS (NIHSS on admission minus NIHSS 24 hours later) were independent parameters affecting HT risk. Multivariate analysis showed that the presence LVO and also older age, female sex, lower delta NIHSS, HT, stroke-associated infection, CRP levels ≥ 10 mg/L, and higher WBC count affected unfavourable outcome on discharge. LVO did not affect in-hospital mortality.

Conclusions
LVO in AIS patients treated by IVT or IVT and MT affects the risk of HT and unfavourable short-term outcome but not in-hospital mortality.