A 46-year-old man with a history of hypertension, smoking, and alcohol use experienced a stroke on waking up with left limb weakness (4/5) and slurring speech on August 30, 2020. He was diagnosed to have a right internal carotid artery (ICA) territory infarct based on non-contrast computed tomography (NCCT) at local hospital. Despite antiplatelet therapy with aspirin 100 mg/d and clopidogrel 75 mg/d, over the next 3 days, left limb weakness progressively worsened (2/5), accompanied by somnolence (GCS 3 + 5 + 6). Therefore, he was transferred to our hospital on September 2, 2020. The Glasgow Coma Scale (GCS) score was 13/15. The head NCCT revealed new infarcts in the right internal watershed area and CT perfusion (CTP) showed a 100.3 mL mismatch of bilateral cerebral hemispheres, indicating that a considerable penumbral region was present in the supply area of each internal carotid artery (ICA) (Fig. 1a and b). Emergent EVT was performed under general anesthesia. The patient received IV heparin (50 U/Kg) before the surgical procedure. Preprocedural angiogram showed a double-lumen sign in the ascending segment of the right ICA with severe stenosis of the true lumen and linear stenosis in the ascending segment of the left ICA, suggesting dissections (Fig. 1c and d). The anterior communicating artery (ACom A) and the right posterior communicating artery (PCom A) were not open, and the left posterior cerebral artery (PCA) mildly compensated the left middle cerebral artery (MCA) through ipsilateral PCom A (Fig. 1e). Because we judged that the right ICA was the main vessel responsible for stroke, and worried about the risk of hyperperfusion-related bleeding in the simultaneous treatment of bilateral ICAs, we decided to treat right ICA first. An 8F Envoy guide catheter (Johnson & Johnson Co. Ltd., New Brunswick, NJ, USA) and 5F MPA catheter were introduced into the distal common carotid artery (CCA) by applying a coaxial technique. After traversing the true lumen with a Trevo Pro 18 microcatheter over a Synchro-2 microwire (Stryker Corp., Fremont, CA, USA), a Solitaire FR 6 × 30 mm stent-retriever (Medtronic Inc., Wexford, PA, USA) was temporarily deployed at the key flow-limiting site (Fig. 1g). An angiogram showed an image of a patent true lumen with a significantly reduced false lumen. After observation of 30 min, blood flow was maintained well, and ipsilateral anterior cerebral artery (ACA) compensated left ACA through ACom A. Thus, the Solitaire stent was detached (Fig. 1h). After recovery from anesthesia, the muscle strength of left limb was improved from grade 2/5 to grade 3/5, but the somnolence was not improved with a 13/15 GCS. Repeated CTP revealed that the perfusion of the right anterior circulation recovered, but a large area of hypoperfusion in the left anterior circulation was still seen (Fig. 1i and j). Due to concerns about clopidogrel resistance, the dual antiplatelet regimen was adjusted to aspirin 100 mg/d and ticagrelor 90 mg twice daily. On the 6th day after the procedure, the patient suffered from a generalized seizure and became stupor with a 9/15 GCS. Further, the muscle strength of right limb was decreased to grade 2/5. But no new lesions were found on the emergent head NCCT. Nevertheless, head CTP showed a new core infarction of 18.2 mL in the left frontal lobe with a penumbra of 100.4 mL in the left anterior circulation (Figs. 2a and b). Then, an emergent EVT was performed again. The angiogram revealed that the right ICA was patent with an inadequate compensation to the left anterior circulation via ACom A, and left ICA was occluded (Figs. 2c and d). A triaxial assembly including an 8F Mach1 guide catheter (Boston Scientific, Marlborough, MA, USA), AXS Catalyst 6 (Stryker Corp.), and a Trevo Pro 18 microcatheter over a Synchro-2 microwire were navigated through the left dissected segment (Fig. 2e). Subsequently, the Catalyst 6 and guide catheter were successively withdrawn to the beginning of the ICA under continuous negative pressure application, namely the simple catheter-passing (SCP) technique. Several dark red emboli were captured by Catalyst 6. A repeated angiogram showed that the left ICA was successfully recanalized and the structure of the dissection was fully revealed (Fig. 2f). After traversing the true lumen with the Pro 18 microcatheter over a Synchro-2 microwire, a Solitaire FR 6 × 30 mm stent-retriever was temporarily deployed at the key flow-limiting site (Fig. 2g). A subsequent angiogram showed that the antegrade blood flow was significantly improved and the dissecting aneurysm disappeared. After observation of 30 min, the Solitaire stent was detached. After recovery from anesthesia, the patient's consciousness became clear with a 15/15 GCS, the tracheal intubation was removed on the following day, and the muscle strength of four limbs was significantly improved to grade 4/5. A repeated head NCCT showed infarction in the left frontal lobe, but repeated head CTP showed that the cerebral perfusion of bilateral anterior circulations was recovered (Figs. 2j and k).
After 3 months of dual antiplatelet therapy, another 3 months of aspirin single antiplatelet therapy was followed. The modified Rankins Scale score (mRS) was 1 at the 90-day follow-up. Follow-up neck CTA at three months showed no residual lesion in both ICAs. No relapse of cerebral ischemic events during the 15-month follow-up occurred. A recent neck CTA showed that both ICAs remained patent without relapse of dissection (Fig. 3).