2025 年 19 巻 1 号 論文ID: cr.2024-0106
Objective: Not many reports of subclavian artery occlusion complicated by vertebrobasilar junction aneurysm have been published, and no cases have been treated using a distal radial approach. Our case report highlights the effectiveness of this approach in comparison to previous findings.
Case Presentation: An 82-year-old woman was referred to our hospital because of an enlarged vertebrobasilar junction aneurysm. The DSA and CTA results revealed a left subclavian artery occlusion, meandering of the descending aorta, and an aneurysm of the descending aorta. We performed coil embolization using the right radial and left distal radial artery approaches. Considering that the left subclavian artery occlusion was related to the aneurysm enlargement, we decided to perform left subclavian artery stenting. Left subclavian artery stenting was performed 1 month after coil embolization using the same approach. The patient was discharged on postoperative day 8 without complications.
Conclusion: Vertebrobasilar junction aneurysm and subclavian artery occlusion were treated via a safe and minimally invasive approach through the right radial and left distal radial artery approaches.
Vertebrobasilar junction aneurysms are relatively rare, accounting for only 0.5% of all cerebral aneurysms.1) Per previous reports, they are caused by hemodynamic loading resulting from subclavian artery occlusion.2) However, only a few cases of subclavian artery occlusion complicated by a vertebrobasilar junction aneurysm have been reported so far to our knowledge,3–7) and no cases were treated using the distal radial approach. We successfully treated a patient with subclavian artery occlusion and a vertebrobasilar junction aneurysm using the distal radial artery approach. Our case report highlights the effectiveness of this approach in comparison to prior findings.
An 82-year-old woman was referred to our hospital after an enlarged vertebrobasilar junction aneurysm was found on CT in another hospital. No neurological symptoms were present at the time of her visit. The DSA and 3-dimensional (3D) CTA results revealed an 11 mm saccular aneurysm at the vertebrobasilar junction and left subclavian artery occlusion (Fig. 1A and 1B). The aneurysm had increased by 4.0 mm and the bleb had become more prominent on magnetic resonance angiography (MRA) over 6 years (Fig. 1C and 1D). CTA revealed subclavian artery occlusion, meandering of the descending aorta, and an aneurysm in the descending aorta.
We considered that the left subclavian artery occlusion was associated with aneurysm enlargement and that cerebral aneurysm treatment and left subclavian artery stenting were required. However, there was concern about contrast nephropathy due to the increased use of contrast media when a 1-stage treatment was chosen. Thus, we decided to treat them in 2 stages. The vertebrobasilar junction aneurysm had enlarged. Considering the risk of rupture, it was treated before the subclavian artery occlusion. Coil embolization of the aneurysm at the vertebrobasilar junction was performed under general anesthesia. Because of the highly tortuous descending aorta, the radial artery approach was chosen instead of the femoral artery approach. From the perspective of proficiency, we have chosen the radial artery approach for the right side, and the distal radial artery approach for the left side because of the surgeon’s comfort. Verapamil (5 mg) and isosorbide nitrate (5 mg) were injected arterially via the cannula of the puncture needle from the radial artery. The radial artery was dilated to 2.9 mm. Heparin was injected intravenously to achieve the target-activated clotting time of 300 s. A 4-French, 80-cm FUBUKI Dilator Kit (Asahi Intecc, Aichi, Japan) was inserted from the left distal radial artery (Fig. 2A). A 6-French, 80-cm FUBUKI Dilator Kit was inserted from the right radial artery (Fig. 2B). A 4-French, 125-cm AXS Vecta 46 catheter (Stryker, Kalamazoo, MI, USA) was advanced into the left vertebral artery, while a 6-French, 115-cm SOFIA SELECT catheter (Terumo, Tokyo, Japan) was introduced into the right vertebral artery. Initially, we attempted coil embolization using the double microcatheter jailing technique from the bilateral vertebral arteries following the partial deployment of the LVIS stent system (4.5 × 32 mm, Terumo) from the basilar artery to the right vertebral artery. However, the coil deviated easily from the aneurysm, and we decided to revise the plan to place the LVIS system in the left vertebral artery from the basilar artery. The Excelsior SL-10 (Stryker) and Headway 17 (Terumo) microcatheters, guided by a Synchro SELECT microguidewire (Stryker), were advanced into the aneurysm via the right vertebral artery. Stenting was performed by guiding a 4-French, 125-cm AXS Vecta 46 (Stryker) and Headway 21 (Terumo) with an ASAHI CHIKAI 14 microguidewire (Asahi Intecc). The LVIS system 4.5 mm/32 mm (Terumo) was placed from the basilar artery to the left vertebral artery. Coil embolization was performed using the double microcatheter jailing technique and the stent-assisted coiling method (Fig. 2C and 2D). Left subclavian artery stenting was performed 1 month after coil embolization under general anesthesia. The left distal radial artery was punctured after dilating the right radial artery as previously explained. Using a dilator, the tip of an 8-French (2.64 mm outer diameter), 90-cm OPTIMO (Tokai Medical Products, Aichi, Japan) was placed at the origin of the left vertebral artery. The balloon at the tip of the OPTIMO was dilated to prevent embolic complications in the vertebral artery during passage through the occlusion by the microcatheter (Corsair PV; Asahi Intecc) and predilation using a balloon catheter (Matacross RX 6 mm/20 mm; Terumo; Fig. 3A and 3B). A snare was deemed necessary to guide the wire from the left subclavian artery into the descending aorta; therefore, we guided a 6-French, 90-cm FUBUKI Dilator Kit (Asahi Intecc) from the right radial artery. However, the wire went to the descending aorta without a snare. Pretreatment angiography revealed vascular diameter just distal of the occluded left subclavian artery was 7.9 mm; thus, we decided to use Express LD 8 mm/37 mm (Boston Scientific, Marlboro, MA, USA) at the occluded place of the left subclavian artery. The blood flow in the left vertebral artery changed from retrograde to antegrade 20 min after stenting. There were no surgery-related complications. Diffusion weighted imaging (DWI)-MRI performed 1 day after stenting revealed no hyperintense areas. The patient was discharged on postoperative day 8. CTA performed after discharge revealed no in-stent stenosis (Fig. 3C and 3D), and the bilateral radial arteries were well palpated. Because geographical constraints limits access to our facility for outpatient follow-up, the patient’s final visit to our outpatient department occurred 2 months postoperatively. Subsequently, at the patient’s explicit request, follow-up care was transferred to their primary referring physician. As the patient declined cerebral angiography, the patency of the left subclavian artery stent and the status of the associated aneurysm could not be evaluated for potential restenosis or recurrence.
Seven cases of occlusion of the left subclavian artery complicated by a cerebral aneurysm have been reported (Table 1).3–7) These aneurysms more commonly arose in women, and the lesions presented with the onset of subarachnoid hemorrhage in 6 out of 7 patients.3–7) Both endovascular treatment and direct surgery have been used to treat this type of cerebral aneurysm. However, endovascular surgery is often preferred because of the proximity of the aneurysm site to the brainstem and the presence of several perforating branches in the vicinity.6,7)
| Case | Authors | Age, sex | Onset | Location | Access | Treatment |
|---|---|---|---|---|---|---|
| 1 | Nakashima et al. (1999)3) | 75, F | SAH | Rt.VA-PICA | – | Neck clipping |
| 2 | Horowitz et al. (2001)4) | 61, F | SAH | Vertebrobasilar junction | FA | SAC |
| 3 | Zaidat et al. (2007)5) | 73, F | Incidental | Rt.VA-PICA | Rt. brachial | SAC |
| 4 | Okuhara et al. (2017)2) | 77, F | SAH | Vertebrobasilar junction | FA | Subclavian PTA + PAO |
| 5 | Murumkar et al. (2020)6) | 65, F | SAH | Vertebrobasilar junction | Rt. FA | Subclavian PTA + BAC |
| 6 | Cornelissen et al. (2022)7) | 73, M | SAH | Vertebrobasilar junction | Rt. FA | BAC |
| 7 | Cornelissen et al. (2022)7) | 73, F | SAH | Vertebrobasilar junction | – | Neck clipping |
| 8 | Present case | 82, F | Incidental | Vertebrobasilar junction | Rt. RA/lt. dRA | SAC → subclavian PTA/stent |
BAC, balloon-assisted coiling; dRA, distal RA; F, female; FA, femoral artery; M, male; PAO, parent artery occlusion; PICA, posterior inferior cerebellar artery; PTA, percutaneous transluminal angioplasty; RA, radial artery; Rt., Right; SAC, stent-assisted coiling; SAH, subarachnoid hemorrhage; VA, vertebral artery
In this case, the vertebrobasilar junction aneurysm was classified as “a terminal aneurysm” due to the subclavian steal phenomenon. In terminal aneurysms, a large hemodynamic flow exerts direct and shear stress on the aneurysm wall, which increases the risk of aneurysm enlargement and recurrence.8,9) After adequately explaining this to the patient, we decided to perform revascularization. However, due to the patient’s advanced age, the single-stage treatment raised concerns about contrast-induced nephropathy because much contrast medium was required. The vertebrobasilar junction aneurysm had enlarged, and considering the risk of rupture, it was to be treated before the subclavian artery occlusion. However, the disadvantages of the 2-stage treatment include stenosis and occlusion due to multiple punctures.10) Thus, a flexible approach is needed for each case.
In this case, embolization with a simple technique was deemed difficult because the aneurysm was wide-necked. In past cases in which coil embolization via the contralateral vertebral artery approach alone was difficult, percutaneous transluminal angioplasty (PTA) of the occluded left subclavian artery via the transfemoral approach was followed by balloon-assisted coiling or parent artery occlusion. However, the femoral artery approach was deemed unsuitable in the present case because of the meandering descending aorta and the presence of an aortic aneurysm. Therefore, the patient was treated using the right radial and left distal radial artery approaches, and the treatment was completed without complications. We used a 4-French guiding sheath and a 6-French guiding sheath during the treatment. Fuga et al.11) reported a 40% radial artery occlusion rate after aneurysm treatment using a FUBUKI 6-French guiding sheath. They recommended a diameter of at least 2.5 mm when using the radial artery approach. In our case, we confirmed that the diameter of the radial artery was 2.9 mm after the intra-arterial administration of the vasodilator. Therefore, the possibility of the occurrence of radial artery occlusion was considered low.
The prevalence of subclavian steal syndrome has been reported to be 0.6%–5.4%, with left subclavian artery lesions accounting for 82% of all cases.12) Endovascular treatment has recently been used to treat subclavian steal syndrome, and the incidence of stroke which could be severe after treatment was reported as 2.6%.13) The transfemoral approach has been reported to be associated with more embolic complications than the trans-radial approach.14) In this report, the transfemoral approach tended to require a large-caliver catheter and manipulation in the aorta, which could explain the high likelihood of plaque dispersal in the aorta.14) In patients diagnosed with the subclavian steal phenomenon, the placement of the large-caliber guiding catheters in the unaffected subclavian and vertebral arteries may lead to hemodynamic compromise of the basilar artery flow. In the present case, the adequate caliber of the right vertebral artery presumably prevented any ischemic complications during the aneurysm intervention. Furthermore, when the contralateral vertebral artery shows an inadequate caliber, subclavian artery revascularization prior to the aneurysm intervention should be considered.
The use of a balloon guide catheter via the transbrachial artery approach during stenting for left subclavian artery occlusion has been reported.15) During PTA for the subclavian artery, inflating the balloon guide catheter at the origin of the right vertebral artery can prevent embolism into the vertebral artery.15) The same effect might have occurred in the present case, suggesting a more minimally invasive treatment.
The distal radial artery approach results in reduced postoperative activity restrictions for patients and reduced risk of radial artery occlusion16) compared with the radial artery approach. For left-hand approaches, it has the advantage of improving the operator’s intraoperative comfort.17) Moreover, considering the shorter postoperative rest time and hemostasis time, as well as the lower risk of retroperitoneal hematoma compared with the femoral artery approach, it is considered to be a safer and less invasive treatment approach. With advancements in endovascular treatment equipment and smaller catheters, the distal radial artery approach could become the preferred treatment strategy for subclavian artery occlusion in the future. After treatment, we confirmed the patency of the radial artery by palpation; however, we were unable to confirm it via ultrasonography as the patient was to be followed up at another hospital. Ideally, ultrasonography should have been performed.
Safe and minimally invasive treatment of vertebrobasilar junction aneurysm and subclavian artery occlusion was achieved using the right radial and left distal radial artery approaches.
The authors declare that they have no conflicts of interest.
