Alternative endovascular approach via the ACOM (anterior communicating artery) in complex tandem occlusion: A case report

Introduction: In acute ischemic stroke, large vessel occlusions carry a high risk of mortality and severe functional dependence. Mechanical thrombectomy is the mainstay reperfusion treatment in suitable patients, and successful recanalization is one of the most important factors associated with favorable clinical outcome. Tandem occlusions and cervical ICA pathologies, however, can technically limit the standard antegrade approach. Transcirculation interventions (via the anterior and posterior communicating arteries) can offer an alternative/rescue route in selected patients with suitable anatomy. We present a case highlighting the role of transcirculation thrombectomy via the anterior communicating artery (ACom) in complex ICA–middle cerebral artery (MCA) tandem occlusion.Case: A 46-year-old man presented 3 hours after symptom onset with right-sided weakness and inability to speak or understand. He had hypertension. Neurological examination showed global aphasia, right homonymous hemianopia, flattening of the right nasolabial fold, and muscle strength of 2/5 in the right upper and lower extremities. The NIHSS (National Institutes of Health Stroke Scale) score was 23. Non-contrast brain computed tomography showed a hyperdense vessel sign in the left MCA M1. The Alberta Stroke Program Early CT Score (ASPECTS) was 9. Computed Tomography Angiography (CTA) showed a left ICA tandem occlusion. After informed consent was obtained, the patient was transferred to the angiography suite. Angiography showed a “candle flame” appearance in the left cervical ICA (Figure 1-A). Although the dissection segment was crossed with a microcatheter and the true lumen was followed, the segment of the distal cervical ICA thought to be pseudoaneurysmal could not be crossed. Because the ACOM and PCOM (posterior communicating artery) were patent on CTA, the left MCA M1 was reached via the ACOM by advancing from the right CCA (common carotid artery) (Figure 1-B). Two thrombectomy passes with a Trevo 3x32 mm stent retriever and intra-arterial thrombolytic therapy were performed. Clinical improvement was observed during the procedure. On the control run, the thrombus was seen to have migrated to the left ACA A1-A2 segment (Figure 2). Because of the dramatic clinical improvement, and given that the MCA was thought to fill via the PCOM, the procedure was terminated (NIHSS: 9). CTA also showed left MCA filling via the PCOM. At the 1-month follow-up, the patient had only mild paresis of the right upper extremity.Discussion/Conclusion: Transcirculation thrombectomy has primarily been reported in case series and has generally been described as a feasible and safe approach in selected patients. In complex vascular anatomy where the standard antegrade approach cannot be used, transcirculation thrombectomy should be considered an alternative/rescue treatment option when the collateral anatomy is suitable.Keywords: