CASE REPORT
Successful Treatment of a Ruptured Left Internal Carotid Artery Aneurysm with a Type III Aortic Arch Using an α-shaped Guiding Catheter: A Technical Case Report
2024 Volume 11 Pages 339-344
Details
2024 Volume 11 Pages 339-344
In endovascular therapy, the induction and stable placement of the guiding catheter (GC) are not only the initial steps but also crucial techniques influencing treatment success. However, in some cases, GC induction is challenging due to variations in the aortic arch or tortuosity of the blood vessels. In the present case, endovascular therapy was carried out for a ruptured aneurysm in the dorsal portion of the left internal carotid artery. However, conventional GC could not be induced because of the type III aortic arch and extremely steep angle. By switching to an α-shaped GC, employed in conjunction with a distal access catheter, we were able to reach the aneurysm with a microcatheter and successfully complete the treatment. The tip of the α-shaped GC was positioned in the ascending aorta and thus required various considerations in terms of setup and device selection when compared to conventional techniques. This is the first report of the use of this catheter for the acute treatment of ruptured cerebral aneurysms. In this report, we share our experience and the effectiveness of using this catheter while highlighting our considerations.
When conducting endovascular therapy, a guiding catheter (GC) must be guided to the internal carotid artery (ICA). To ensure safe and smooth performance of the procedure, subsequent stabilization of the GC in the ICA is crucial. Cases where the induction and placement of the GC are extremely difficult due to variations in the aortic arch or tortuosity of blood vessels are uncommon.1) In such cases, measures such as using a Newton-shaped GC2) or changing the approach route to include transradial or direct carotid artery puncture may be utilized as bailout.3,4) However, specialized catheters including the Newton-shaped GC may not always be readily available. Moreover, changing the approach involves the addition of new punctures, thus increasing the risk of complications.3,4) The α-shaped GC is considered a useful new option for addressing these issues, but its operation necessitates techniques different from conventional methods. In this report, we present the successful use of an α-shaped GC in emergency surgery for subarachnoid hemorrhage due to a ruptured cerebral aneurysm, which yielded favorable results.
The patient was an 87-year-old woman with hypertension who was found unconscious at home and brought in via emergency services. Computed tomography of the head revealed a subarachnoid hemorrhage, classified as Fisher Group 4. Upon arrival, her Glasgow Coma Scale was E3V4M6, and she presented mild paralysis in the right upper limb, with slight internal rotation observed on the Barre test, corresponding to a World Federation of Neurological Surgeons grade 3 condition. Additional magnetic resonance imaging of the head demonstrated aneurysms in the dorsal aspect of the left ICA, bifurcation of the left middle cerebral artery, and bifurcation of the internal carotid and ophthalmic arteries. Among these, the aneurysm in the dorsal aspect of the left ICA exceeded 20 mm in size and was accompanied by blebs, leading us to conclude that it was the cause of the subarachnoid hemorrhage. Therefore, for this aneurysm, we decided to proceed with cerebrovascular surgery. Moreover, magnetic resonance angiography carried out simultaneously from the aortic arch to the cervical ICA showed that the bifurcation of the left common carotid artery (CCA) was type III, and there was a bovine aortic arch (Fig. 1A, B).
(A) Frontal view of magnetic resonance angiography (MRA). (B) Fifteen-degree oblique view of MRA. (C) Frontal view of digital subtraction angiography.
Surgery was conducted under general anesthesia via the right femoral artery puncture. Based on the preoperative imaging, a 6 Fr Simmons-type catheter was selected as the inner catheter (IC). Initially, an attempt was made to guide an 8 Fr FUBUKI catheter (Asahi Fubuki 8 Fr, Asahi Intecc Co., Ltd., Aichi, Japan) to the ICA (Fig. 1C). However, when the 0.035-inch guidewire (GW) was advanced to the ICA, the IC did not follow. An alternative approach was subsequently attempted by exchanging the IC with a JB2-type catheter while leaving the GW in the ICA. However, the IC slipped off during induction. Switching to a more supportive GW did not facilitate IC induction. Consequently, the decision was made to abandon the induction of the GC into the ICA and to switch to an approach from the aortic arch using a distal access catheter (DAC). Using an α-shaped GC, ROADMASTER αCurve (85 cm, GOODMAN Co., Ltd., Aichi, Japan), with a JB2 catheter as the IC, an attempt was made to advance the GW to the ICA. However, accessing the CCA was difficult because of the JB2 catheter's tip shape, which tends to orient toward the descending aorta side in the small curvature of the aortic arch (Fig. 2A). Therefore, the IC was changed to an AXS Vecta71 distal access catheter (125 cm Stryker Neurovascular, Fremont, California, USA). Even with this configuration, it is difficult to select the CCA using a GW. After adjusting the position of the GC and inserting and retrieving the DAC, the DAC was utilized to select the CCA. With the GC remaining positioned in the aortic arch, using the GW, the DAC was guided to the distal portion of the ICA (Fig. 2B). Vascular imaging was carried out, and an operative view was acquired (Fig. 3A, B). Considering the ruptured giant cerebral aneurysms, a balloon-assisted technique was planned. However, the TransForm Occlusion Balloon Catheter (4 × 7 mm) (Stryker Neurovascular), a super compliant-type balloon catheter (BC), was not sufficiently long to reach the aneurysm. Attempting to advance the DAC over the BC led to behaviors that indicated potential slippage. Consequently, the BC was kept within the GC as a rescue option in case of intraoperative rupture, and a simple technique was applied using an Excelsior SL-10 90° microcatheter (150-cm Stryker Neurovascular) to complete the procedure. Despite being initially in a dome-filling state, sufficient intrasaccular embolization was obtained (Fig. 3C, D).
(A) A 6 Fr JB2-type catheter (arrowhead) is inserted into the ROADMASTER αCurve (arrow), with its tip directed toward the descending aorta. (B) A DAC (AXS Vecta71, double arrow) inserted into the ROADMASTER αCurve (arrow) is advanced to the left common cervical artery.
(A) Frontal view of operative view. (B) Lateral view of operative view. (C) Frontal view at the end of coil embolization. (D) Lateral view at the end of coil embolization.
The patient provided informed consent for publication of this case report and accompanying images.
The primary step in carrying out endovascular therapy is to guide and stabilize the GC in the target vessel. Without this, navigating an MC into the intracranial artery is impossible, rendering the treatment unachievable. Unfortunately, variations in the aortic arch or the tortuosity of blood vessels sometimes make GC induction extremely difficult, particularly during the commonly used femoral artery approach.1) In such cases, various methods can be utilized to complete the treatment. Broadly speaking, these include changing the puncture site to use a different approach route or switching to a Newton-shaped GC, such as the Neuro-EBU vascular catheter (SILUX Co., Ltd., Kawaguchi City, Saitama Prefecture, Japan).2-4) Previously, when continuing the procedure from an already punctured femoral artery, the only option was to employ a Neuro-EBU. However, the ROADMASTER αCurve used in this case is a new 8 Fr GC designed for the femoral artery approach, similar to the Neuro-EBU. This GC has an α-shape at the tip (Fig. 4A), but the shape is flexible enough to allow it to be easily opened by inserting an IC. As the IC is inserted, the tip gradually opens from an α-shape to a U-shape according to the insertion length (Fig. 4B, C, D). The target vessel can be selected by adjusting the degree of opening and the position of the GC. When the IC was fully inserted into the target vessel, the GC made contact with both the outer and inner walls of the aortic arch, thereby providing support (Fig. 4E). Additionally, as in this case, to obtain sufficient support, the GC along the outer wall must be aligned and the tip within the ascending aorta must be deployed (Fig. 2B).
(A) The tip shape of ROADMASTER αCurve. (B) At this stage, the ROADMASTER αCurve has advanced into the ascending aorta, but the IC has not yet reached the tip. (C) At the stage when the inner catheter (IC) has just started to emerge from the tip of the ROADMASTER αCurve, the α shape begins to open. (D) When the IC has emerged sufficiently from the ROADMASTER αCurve, the tip shape opens into a U-shape. (E) When the IC is sufficiently inserted into the target vessel, the ROADMASTER αCurve makes contact with both the outer and inner curves of the aortic arch, providing adequate support.
When conducting treatment with the ROADMASTER αCurve, the α-shape must be formed first. According to the package insert, when approaching the aortic arch, the IC and GW should be pulled back to just before the shape portion of the GC, and while applying clockwise torque, the GC is advanced, naturally forming the α-shape. However, based on our experience with this one case at our institution, in instances where there is significant tortuosity of the descending aorta, the torque may not be transmitted to the tip, which potentially causes the GC to twist at the proximal tortuous segment. As such, it is preferable to advance initially without torque and to only apply gentle torque if the shape cannot be formed. In this case, it was unnecessary to apply torque when forming the α-shape.
Once the α-shape has been formed, the process continues with the selection of the target vessel and intracranial manipulation. In completing the procedure using this GC, there were four areas where the conventional technique faced difficulties and required consideration. The first was "what to use for the IC," the second was "approach manipulation from the aorta to the intracranial artery," the third was "the length of the DAC," and the fourth was "the setup of connectors and other equipment."
First, regarding the selection of the IC, a DAC must be used from the beginning rather than a JB2 diagnostic catheter. As the GC progresses through the aorta, it will inevitably pass through the outer curve, causing the tip to naturally orient toward the inner curve when the α-shape is opened. When a JB2 catheter was inserted at this point, it tended to orient toward the aortic arch (Fig. 2A). Moreover, in most cases where the ROADMASTER αCurve is employed, the variations in the aortic arch are type 2 or type 3, and the entrance of the target CCA is located in the proximal part of the ascending aorta. As such, a system that tends to orient toward the descending aorta is not compatible. Moreover, the ROADMASTER αCurve is designed to adjust the width of the tip deployment by inserting and retrieving the IC, making vessel selection easier. However, when using a diagnostic catheter that already has its own angle, adjustments in two places are necessary, which leads to complexity in the operation and thinking. Using a DAC from the beginning, the direction of catheter advancement aligns directly with the width of the GC tip deployment, simplifying the procedure. Moreover, directly advancing the DAC after vessel selection contributes to improving the time efficiency.
Second, the approach from the aorta to the intracranial arteries represents a significant shift from traditional techniques. In conventional methods, a diagnostic catheter such as the JB2 or Simmons catheter is initially advanced into the target vessel. A GW was then placed ahead, and the diagnostic catheter was navigated distally to serve as a guide for advancing the GC. Even when using the Neuro-EBU, the approach of selecting the target vessel with the diagnostic catheter remains the same. In this case, we initially attempted to follow the traditional method using a JB2 diagnostic catheter and a GW to select the target vessel. However, operating with the IC and GW often results in deviations to the left of the intended target position, which can make the procedure difficult to perform. This is due to the characteristic of the ROADMASTER αCurve catheter, in which the tip shape opens up more as the IC and GW are advanced from the catheter (Fig. 4B, C, D). As the IC and GW advance, they not only progress forward but also tend to shift leftward. Therefore, the following approach is recommended when using the ROADMASTER αCurve. First, advance the DAC into the ascending aorta and open the tip shape of the ROADMASTER αCurve until it faces the orifice of the target vessel. Next, this position was maintained, and the entire system was retracted. At this stage, the tip of the DAC is usually oriented to the left of the orifice of the target vessel; so by pulling the DAC back, the tip shape of the ROADMASTER αCurve can be adjusted to point more to the right. This ensured that the tip of the DAC consistently faced the target vessel orifice. Finally, adjust the DAC so that its orientation is slightly to the right of the orifice; then, advance it to properly insert it into the target vessel. By slightly advancing the GW from the DAC at this stage, fine adjustments around the orifice become easier, and this helps reduce the risk of slippage caused by changes in IC stiffness as the GW advances. Another important consideration is that when retracting the entire system, support may be compromised if the GC moves away from the outer wall or if the tip of the GC extends into the aortic arch. Therefore, to maintain adequate support, it is necessary to advance the GC along the ascending aorta using the IC as an axis.
Regarding the third point, which is the length of the DAC, it is advisable to select one that is 125 cm long. Currently, there is only one standard length (85 cm) available for the ROADMASTER αCurve. Moreover, because of this concept, the tip of the GC is mostly located in the ascending aorta. Even if it can be inserted up to the CCA, the distance is minimal. Therefore, the distance to the ICA, which can be omitted in conventional GCs, becomes necessary. For example, in this case, although the patient was a petite woman with a height of 145 cm, simple measurements using frontal and lateral angiography images revealed that the distance from the entrance of the CCA to the distal cervical portion of the ICA was approximately 21 cm. Based on the report by Choudhry FA et al., the length from the aortic arch to the prepetrous ICA is 22.2 ± 2.2 cm on the right and 20.8 ± 1.9 cm on the left.5) For simplification, by adding the effective length of the GC itself (85 cm), 3 cm for the hub, 7 cm for a typical Y-connector, and the aforementioned 21 cm, the total was 116 cm. Therefore, even a 115-cm DAC may not reach the intracranial vessels. To maximize the capability of the DAC, it should be advanced into the intracranial vessels, which requires the selection of a DAC with a length of 125 cm.
The fourth point is the setup of the connectors, which must be considered to maximize the effective lengths of the DAC and MC. In this case, a hemostatic valve was connected to the ROADMASTER αCurve, and two Y-connectors were connected to the DAC. Connecting the hemostatic valve to the ROADMASTER αCurve provided approximately 5 cm of extra effective length for the DAC, which was beneficial. However, the setup for connecting the two Y-connectors to the DAC could be enhanced. Numerous MCs utilized in coil embolization procedures, including those employed in this case, have a length of approximately 150 cm. Nevertheless, when attaching a hub and Y-connector to the 125-cm DAC, the length becomes approximately 136 cm with one Y-connector and approximately 143 cm when two Y-connectors are stacked. Given the flexibility of the catheter, additional length is difficult to provide. Although the aneurysm was located proximally on the dorsal side of the C2 portion of the ICA, the BC (150 cm) inserted from the DAC with two stacked Y-connectors could not reach the neck of the aneurysm. Even the MC inserted from the DAC with one Y-connector faced difficulty in reaching the aneurysm initially because of flexion of the GC and DAC caused by the inserted BC. Pulling the BC back into the DAC to remove flexion allowed the MC to be successfully guided into the aneurysm. Therefore, when assembling the treatment system, it is crucial to consider the lengths of the Y-connectors and T-connectors and switch to other devices, such as hemostatic valves or triple connectors, to provide even a slight increase in the effective length. As these may vary by facility and whether the procedure is an emergency or not, it is advisable to confirm what is available at regular times.
This report represents the first documentation of acute-phase treatment for ruptured intracranial aneurysms using an α-shaped GC. Consequently, areas of immaturity are still present in the procedural techniques and device selection. However, conducting surgery using a new approach for cases with difficult access has significance. This is particularly true in emergency cerebrovascular surgeries, where preoperative information is scarce and device selection is often limited, as seen in percutaneous thrombectomy therapy. In such scenarios, using a tool such as the α-shaped GC is highly effective. By continuing to accumulate case experiences and share insights, access techniques will be expected to become more refined, and more desirable device setups will be discovered. Moreover, if the ROADMASTER αCurve itself gains more length variations or if a suitable DAC is developed, the duration of the procedure of guiding the GC to the carotid artery may be shortened.
We would like to thank Editage (www.editage.com) for English language editing.
The authors have no conflicts of interest to declare.
