Abstract 56: Thrombolysis in Selected Patients with Wake Up Stroke is Feasible with Similar Safety as Thrombolysis in 0-4.5 Hours
Introduction Thrombolysis with alteplase is effective within 4.5 hours of ischaemic stroke onset in patients with no or early ischaemic changes (EIC) on CT. Patients with wake up strokes (WUS) make up to 25' of all strokes but are excluded on the basis of time alone. Emerging data suggest that imaging appearances in many WUS patients are similar to those treated within 4.5 h and recanalisation therapies may be beneficial.
Hypothesis Treatment with alteplase in WUS patients selected on CT imaging findings showing no or limited EIC who would otherwise be eligible for thrombolysis will have functional outcome and bleeding risks similar to those thrombolysed within 4.5 hours of stroke onset.
Methods We analysed registry data between January 2009 and December 2010 for WUS patients thrombolysed on compassionate grounds with consent and compared their outcomes with those thrombolysed within 4.5 hours of stroke onset. Standard guidelines were followed but there was no upper age limit for thrombolysis. WUS patients were thrombolysed if they met all eligibility criteria apart from time and the non-enhanced CT scan showed an Alberta Stroke Program Early CT Score (ASPECTS) of ≥7. CT Perfusion (CTP) mismatch was used as an additional modality for assessing eligibility for thrombolysis in a proportion of WUS patients but was not obligatory. Inclusion criteria for the analysis were defined a priori and were masked to outcomes.
Results The analysis included 356 patients thrombolysed within 4.5 hours of stroke onset and 68 thrombolysed WUS patients. The two groups were comparable for mean age (72.6 v 74.8, years, p=0.28) and vascular risks profile but there were more women in the WUS group (66% v 52%, p=0.034). There were fewer WUS patients with premorbid Rankin Score (mRS) of 0-2 (69% v 84% p=0.01). There were no differences in mean baseline BP (151/85 v 153/84 mm Hg, p=0.55), mean blood glucose (6.5 v 6.5 mmols/L, p=0.99) and mean National Institute of Health Stroke Scale (NIHSS) score (13.2 v 12.6, p=0.44). CTP was undertaken in 26% patients within 4.5 h and in 67% of WUS patients (p<0.0001). The door to needle time was 59 minutes and 73 minutes respectively (p=0.11). There were no differences in mean NIHSS score at 24 hours (9.2 v 8.1, p=0.32), any intracranial haemorrhage (ICH) (17% v 22%, p=0.21), symptomatic ICH (2.5% v 2.9%, p=0.55) and mRS 0-2 at 3 months (49% v 37%, p=0.10) between patients within 4.5 h and WUS patients. Mortality at 3 months was lower in thrombolysed WUS patients (15% v 24%, p=0.063) and became significant after adjusting for co-variates in multiple regression (p=0.024).
Conclusion Functional and safety outcomes after thrombolysis in WUS patients selected using CT imaging based protocols is comparable to that of patients treated within 4.5 h of stroke onset. Our experience suggests that randomization of patients with WUS on the basis of defined imaging criteria in thrombolysis trials is appropriate.
- © 2012 by American Heart Association, Inc.