2672 Thrombolysis of the comatose patient – a case of suspected transient Basilar artery occlusion

Case An 88 year-old functionally independent man presented to the Emergency Department with a Glasgow Coma Scale of three after a witnessed collapse. On examination, the left eye was adducted, the left pupil fixed and dilated at six millimetres, the oculo-cephalic reflex was abnormal, and myoclonus was witnessed in the right side. Babinski was positive bilaterally. Electrocardiogram (ECG) revealed atrial fibrillation. Initial concern was for a catastrophic intracranial haemorrhage however plain Computerised Tomography (CT) scan was normal.

CT angiogram revealed no acute basilar artery (BA) occlusion, however, there was ongoing concern for perforator artery involvement given the clinical picture. As he presented within the thrombolysis window with an excellent premorbid state, thrombolysis was offered as a life-saving treatment.

He subsequently responded remarkably to treatment with vast improvement to consciousness and speech. Magnetic Resonance Imaging (MRI) revealed bilateral infarcts within the BA territory. He was discharged home 15 days later with mild residual left sided ataxia and upward gaze palsy.

Conclusion BA occlusion is a neurological emergency due to the mortality associated with brainstem dysfunction, often presenting with coma.¹ There is evidence for use of Endovascular Clot Retrieval (ECR) for BA occlusion as a life-saving procedure,^{2 3} however literature describing outcomes of thrombolysis for comatose patients without evidence of a BA thrombus is lacking. In this case, we show that brainstem signs in an acutely obtunded patient with relatively innocuous hyperacute vascular imaging, may suggest a transient BA thrombus. Therefore, these patients may benefit from thrombolysis despite initially poor prognostic indicators.

References

1. Chandra RV, Law CP, Yan B, Dowling RJ, Mitchell PJ. Glasgow coma scale does not predict outcome post-intra-arterial treatment for basilar artery thrombosis. American Journal of Neuroradiology [Internet]. 2011;32(3):576–80. Available from: http://www.ajnr.org/content/32/3/576

2. Jovin TG, Li C, Wu L, Wu C, Chen J, Jiang C, et al. Trial of thrombectomy 6 to 24 hours after stroke due to basilar-artery occlusion. New England Journal of Medicine. 2022;387(15):1373–84.

3. Tao C, Nogueira RG, Zhu Y, Sun J, Han H, Yuan G, et al. Trial of endovascular treatment of acute basilar-artery occlusion. New England Journal of Medicine. 2022;387(15):1361–72.