2026 年 13 巻 p. 463-469
In patients who have undergone debranching thoracic endovascular aortic repair, the access route and system for mechanical thrombectomy must be carefully selected on a case-by-case basis. We report an 82-year-old man in whom mechanical thrombectomy was successfully performed via the left brachial artery for occlusion of a bypass graft. He was admitted with impaired consciousness and was diagnosed with left common carotid artery occlusion on magnetic resonance angiography. The patient had previously undergone debranching thoracic endovascular aortic repair with a right subclavian artery–left common carotid artery–left subclavian artery bypass for a thoracic aortic aneurysm 4 years earlier. Because a femoral artery approach was considered unfeasible, mechanical thrombectomy was performed via the left brachial artery. A 6 Fr guiding sheath was advanced into the left brachial artery, and angiography demonstrated that both the bypass graft to the left common carotid artery and the left common carotid artery itself were occluded by a large thrombus. Multiple mechanical thrombectomy attempts using various techniques were performed, and a thrombus measuring approximately 3 cm was retrieved, resulting in successful grade 2c Thrombolysis in Cerebral Infarction reperfusion. For patients who have undergone debranching thoracic endovascular aortic repair, the brachial approach may be considered as a potential alternative when femoral access is not feasible. The choice of access route might be influenced by the specific type of cervical vascular reconstruction and the location of the lesion.
Debranching thoracic endovascular aortic repair (TEVAR), which involves inserting a stent graft after a minimally invasive neck vessel bypass, has become favored over open sternotomy for artificial vessel replacement in patients with aortic arch disease.1,2) Clinicians must select the endovascular access route and system, as well as the neck vessel bypass technique on a case-by-case basis.3) We report a patient with a history of debranching TEVAR in whom mechanical thrombectomy (MT) was performed via the left brachial artery to treat an occluded artificial vessel and an occluded left common carotid artery (CCA).
An 82-year-old man with a history of debranching TEVAR for a thoracic aortic aneurysm was found unconscious at home and was transported to an outside hospital by emergency services. Magnetic resonance imaging (MRI) showed a left cerebral hemisphere infarction and he was transferred to our hospital for further care. At the time of arrival, 15 hours had elapsed since stroke onset. On examination, his Glasgow Coma Scale score was 11 (E3V3M5) and he exhibited right hemiplegia and left conjugate strabismus. His National Institutes of Health Stroke Score was 17. Review of his MRI demonstrated faint high signal intensity in the left temporal lobe on diffusion-weighted and fluid attenuated inversion recovery images (Diffusion-Weighted Imaging - Alberta Stroke Program Early CT Score 9 points); magnetic resonance angiography showed a left CCA occlusion, indicating eligibility for MT (Figure 1). Additionally, the patient's medical history (aside from the thoracic aortic aneurysm) included hypertension, dyslipidemia, and lung cancer (post-radiation therapy). At the time of presentation, electrocardiography revealed no atrial fibrillation. His current medications were aspirin (100 mg once daily), esomeprazole (20 mg daily), atorvastatin (10 mg daily), and azosemide (60 mg daily). The pre-episode modified Rankin Scale score was 3. Based on various physiological assessments, including echocardiography and Holter electrocardiography, cardiogenic embolism was ruled out as the cause of stroke in this patient.
(A) Diffusion-weighted imaging showed faint high signal intensity in the left temporal lobe. (B) Fluid attenuated inversion recovery imaging showed high signal intensity in the same area. Magnetic resonance angiography showed absence of the intracranial left internal carotid artery (C) and occlusion of the origin of the left common carotid artery (D).
The debranching configuration involved a long artificial vessel connecting both subclavian arteries (SCAs), with another artificial vessel branching off from its left end that was connected to the distal end of the left CCA. The original left SCA and the origin of the left CCA were occluded (Figure 2). A femoral approach was considered difficult because it required passing through the stent graft and a considerable length of artificial vessel from the right SCA to the opposite side. Therefore, we elected to use a left brachial approach to perform MT because the target lesion was in the left anterior circulation.
(A) Three-dimensional computed tomography angiography showed that both subclavian arteries had been bypassed via artificial vessels; an artificial vessel connecting to the left common carotid artery branched off from the artificial vessel. (B) Schematic diagram illustrating the relevant vascular anatomy. The asterisk (*) indicates the stent graft deployed in the aorta.
Under local anesthesia, a short 6 Fr sheath was placed in the left brachial artery, and a 90 cm 6 Fr Fubuki guiding sheath (Asahi Intecc, Aichi, Japan) was inserted. The left SCA was selected using a system consisting of a 4 Fr JB2 catheter (Cook Medical, Bloomington, IN, USA) and a 150 cm 0.035-inch guidewire (Terumo, Tokyo, Japan). The guidewire was changed to an E-type guidewire (Terumo) and guided into the artificial vessel connected to the left CCA. Left subclavian angiography revealed thrombotic occlusion in the middle portion of the artificial vessel (Figure 3A). MT was attempted first with a 132 cm AXS Catalyst 6 aspiration catheter (Stryker Neurovascular, Fremont, CA, USA) using the direct aspiration, first pass technique,4,5) then using the stent retriever assisted vacuum-locked extraction technique6) with a 6 × 37 mm Trevo NXT ProVue stent retriever (Stryker Neurovascular). However, recanalization was not achieved. A 100 cm 6 Fr OPTIMO balloon guiding catheter (Tokai Medical Products, Aichi, Japan) was then inserted to block antegrade flow, and after several attempts, a red thrombus was retrieved; however, some thrombus remained in the internal carotid artery (Figure 3B and C). As the thrombus gradually receded and shrunk, it moved distally. A 5 × 37 mm Embotrap III stent retriever (Cerenovus, Irvine, CA, USA) was deployed from the M1 segment distally to retrieve the thrombus. This achieved Thrombolysis in Cerebral Infarction grade 2c recanalization (Figure 3D and E). After the procedure, the access route remained patent.
(A) Occlusion caused by thrombus was observed in the middle section of the artificial vessel forming the left common carotid artery. (B) Mechanical thrombectomy was attempted as described in the main text, but reperfusion was not achieved. (C) After antegrade blood flow was blocked, the same procedure was performed and thrombus retrieval was achieved. However, the residual thrombus migrated and caused occlusion at the distal end of the internal carotid artery. (D) Distal deployment of a revascularization device from the M1 segment enabled retrieval using a combined technique. (E) Grade 2c Thrombolysis in Cerebral Infarction reperfusion was achieved.
The patient's left conjugate strabismus resolved after the procedure, and his right hemiparesis improved, although he still had residual weakness. On manual muscle testing, he exhibited 2/5 strength in the right upper limb and 3/5 strength in the lower limb. His National Institutes of Health Stroke Score improved to 14. Immediately after the procedure, computed tomography showed no intracranial hemorrhage. MRI performed the next day showed no increase in infarction size; magnetic resonance angiography showed recanalization of the left CCA (Figure 4). Prasugrel 3.75 mg daily was initiated as adjuvant therapy, and there has been no subsequent re-occlusion. At the time of discharge, the mRS score was 4.
(A) Diffusion-weighted imaging after the procedure showed no infarction size increase and no new infarcts. (B) Fluid attenuated inversion recovery imaging showed the same. On magnetic resonance angiography, the intracranial left internal carotid artery was visualized (C) and recanalization of the left common carotid artery was observed (D).
Debranching TEVAR is a procedure for thoracic aortic aneurysms that combines cervical vascular reconstruction with TEVAR.7) Because it is minimally invasive, debranching TEVAR is expected to be suitable for older patients.8) However, in patients who have undergone debranching TEVAR, issues may arise in subsequent endovascular procedures, particularly with stent graft passage, cervical branch reconstruction, and artificial vessel injury.9,10) Therefore, practitioners must be prepared to address and manage potential issues with the access route.
In this case, the patient had undergone two-debranching TEVAR for a thoracic aortic aneurysm. In addition to stent graft insertion, a neck bypass (right SCA–left SCA–left CCA) was performed. In a previously reported case where thrombus retrieval therapy was performed after a debranching TEVAR, in which the left CCA was used to reconstruct both SCAs, MT was performed using a right brachial artery approach rather than the femoral approach, and grade 2c Thrombolysis in Cerebral Infarction reperfusion was achieved.9)
Debranching TEVAR is classified based on the cervical branches replaced, depending on lesion location. Replacement of the left SCA is defined as one-debranching, replacement of both the left SCA and CCA as two-debranching, and replacement of all 3 supra-aortic branches (brachiocephalic artery, left CCA, and left SCA) is considered total debranching.11) Regardless of the cervical bypass configuration, the preferred order of access is the femoral artery, followed by the radial or brachial artery, and finally direct carotid puncture.12) In recent years, the transradial approach has been increasingly adopted in neuroendovascular procedures because of its low access-site complication rates and less invasive nature.13,14) When anatomically feasible and large-bore catheters are not required, the transradial approach may represent a useful alternative access route.14,15) However, small vessel caliber, vasospasm, or insufficient catheter support may increase the technical difficulty of radial artery cannulation. In such cases, the brachial approach may serve as an alternative access route.13,16) In a case with left anterior circulation occlusion such as this case, the conventional common femoral artery approach would require navigation through a long artificial graft extending across the anterior neck. This raised concerns regarding potential graft injury and insufficient device length; therefore, the radial or brachial artery approaches were considered more appropriate than the common femoral artery approach.
In general, although MT is usually performed via femoral access, performing it after debranching TEVAR presents unique challenges: the reconstructed cervical vessels often deviate markedly from physiological branching patterns, complicating catheter navigation and increasing the risk of anastomotic or graft-related injury.17) Thus, careful selection of the puncture site is essential, based on both lesion location and graft configuration. Accordingly, the following principles can be applied across different types of debranching TEVAR:
1. The femoral approach is prioritized as the first choice, provided that catheter passage through the stent graft or reconstructed vessels is technically feasible.
2. The catheter route should be kept as short as possible through artificial grafts, as longer graft segments increase the risk of kinking, insufficient device length, and anastomotic damage.
3. When femoral access is unsafe or impractical, a radial or brachial approach is preferred, particularly for lesions in the left anterior or posterior circulation.
4. If the femoral, radial, and brachial accesses are unsuitable, direct carotid puncture may be considered as a last resort.
In summary, while the femoral approach is the default strategy for MT, the final choice of access should be individualized, taking into account graft anatomy, lesion location, and the potential risks of navigating reconstructed vessels. However, the optimal access route should be individualized in accordance with the vascular anatomy, device requirements, and operator experience. Because our observations are based on a single case and limited previous reports, further clinical experience and evidence accumulation are warranted.
Herein, we discuss the etiology and prevention of recurrence in this case. Thrombosis was observed extending from the middle of the artificial vessel to the CCA, suggesting thrombosis originating from the artificial vessel. Although the patient had been receiving single antiplatelet therapy, it is possible that antiplatelet monotherapy was insufficient to adequately prevent thrombus formation after the complex vascular reconstruction of such a long segment. Anticoagulant therapy was considered unnecessary because the expanded polytetrafluoroethylene artificial vessel used for the cervical bypass had a heparin coating on its inner lumen.18) However, several reports have suggested that the long-term antithrombogenic effect of heparin-bonded grafts may become limited over time,19,20) and 4 years had elapsed since graft implantation in this case. Therefore, anticoagulant therapy might have been beneficial in this patient. Additional factors that may also have contributed to thrombus formation are the reduced blood flow within the long artificial graft, structural changes associated with long-term implantation, and patient-related factors such as malignancy. Taken together, the graft thrombosis in this case was considered to be multifactorial rather than attributable to a single cause. There is currently no established standard antithrombotic regimen following debranching TEVAR, and treatment strategies vary among institutions. In addition, although no clear consensus exists regarding the optimal duration of dual antiplatelet therapy (DAPT), it may be reasonable to administer a limited course of DAPT for approximately 1-3 months, followed by single antiplatelet therapy, taking into account the balance between thrombotic and bleeding risks.21) We elected to add prasugrel (3.75 mg daily) and observed no subsequent re-occlusion. Previous reports have shown that antiplatelet therapy is effective for preventing graft occlusion after cardiovascular surgery,22) and DAPT has been reported to improve outcomes compared with antiplatelet therapy alone.23) Therefore, we decided to add another antiplatelet agent in our case.
ConclusionsWe report a patient with a history of two-debranching TEVAR who underwent thrombus removal therapy performed via the left brachial artery approach for artificial vessel occlusion. Although further validation is necessary, the brachial approach might be a viable option for MT in specific cases of debranching TEVAR where the femoral approach is technically difficult.
We thank Edanz (https://jp.edanz.com/ac) for editing a draft of this manuscript.
Author Haruhiko Kishima is one of the Editorial Board members of the Journal. This author was not involved in the peer-review or decision-making process for this paper.
All authors have no conflict of interest.
