Entrapment of microguidewire into perforator during endovascular treatment: Case report and management strategy

Abstract

Despite advancements in endovascular equipment, life-threatening procedure-related complications, including arterial perforation, remain a concern. In particular, microguidewire entrapment in perforating arteries poses a significant risk of arterial avulsion injury. However, limited guidance exists on effectively managing such scenarios, and to the best of our knowledge, no cases of successful resolution of entrapment using nimodipine have been reported to date. A woman in her mid-60s with a history of anterior communicating artery aneurysm coil embolization presented with aneurysm regrowth. During stent-assisted coil embolization, a microguidewire was entrapped in the perforating artery. An additional microcatheter was inserted near the site of entrapment, and 2.3 mg of intra-arterial nimodipine was infused over 15 min while attempting retrieval with extreme caution. The entrapped microguidewire was successfully removed, and the planned stent-assisted coil embolization was completed without complications. Microguidewire entrapment in a perforating artery during endovascular treatment poses the risk of fatal avulsion injury. Gentle and cautious retrieval, supported by sufficient intra-arterial nimodipine administration, may provide a safer approach for managing such complications.

Introduction

Endovascular treatment plays a crucial role in managing neurovascular conditions such as aneurysms and large-vessel occlusions. With advancements in endovascular equipment, the incidence of procedure-related complications has steadily decreased. However, life-threatening complications may still occur and may become more frequent as the number of these procedures continues to increase.^1–3 Among the most serious complications is arterial perforation, ² with a reported incidence of 0.6%–4.9%.^4,5 Although a few reports have highlighted the risk of avulsion injury caused by microguidewire entrapment, particularly in perforating arteries, guidance on managing such scenarios is limited, and to the best of our knowledge, no cases of successful resolution of entrapment using intra-arterial (IA) nimodipine have been reported to date.^6,7 Herein, we report a case of microguidewire entrapment in a perforating artery during endovascular treatment, which posed a risk of arterial avulsion injury; the case was successfully managed with appropriate intervention. We also reviewed management strategies for similar situations.

Case presentation

A woman in her mid-60s, who had undergone coil embolization for an anterior communicating artery aneurysm at an outside hospital in 2017, presented to Chungbuk National University Hospital (Cheongju, Republic of Korea) in early 2024 after follow-up magnetic resonance angiography revealed aneurysmal regrowth. Additional coil embolization was planned, and the patient was started on dual antiplatelet therapy 5 days before the procedure.

Stent-assisted coil embolization was planned under general anesthesia, and written informed consent was obtained from the patient. The procedure was performed via a transfemoral approach using an 8-Fr Cerebase DA guide sheath (Cerenovus, Irvine, CA, USA) advanced into the left internal carotid artery. The guiding catheter tip was positioned in the proximal internal carotid artery using a continuous flushing system. Initial angiography revealed aneurysmal regrowth measuring 4.5 mm in depth, 1.9 mm in height, and 4.2 mm in width (Figure 1(a)).

Figure 1.

Entrapment of a microguidewire in a perforating artery near the anterior communicating artery aneurysm. (a) Initial angiography, performed 7 years after the initial coil embolization, revealed aneurysmal neck regrowth measuring 4.5 mm in depth, 1.9 mm in height, and 4.2 mm in width. (b) During the attempt to select the right A2 segment for stent deployment, the microguidewire was entrapped and could not be retrieved (arrow). The roadmap image revealed displacement of the previously inserted coil mass by a few millimeters (arrowhead), indicating traction-related vascular movement. (c) A second microcatheter was advanced near the site of entrapment (arrowhead), and intra-arterial nimodipine (2.3 mg) was slowly infused. Approximately 15 min later, the microguidewire was successfully retracted (arrow) and (d) postprocedural computed tomography confirmed the absence of subarachnoid hemorrhage.

A 1.7-Fr Excelsior SL10 microcatheter (Stryker, Kalamazoo, MI, USA) with a 0.014-inch Synchro 14 microguidewire (Stryker, Kalamazoo, MI, USA) was advanced toward the A2 segment of the right anterior cerebral artery for stent placement. However, resistance was encountered during the advancement of the microcatheter along the microguidewire, and it failed to progress. Realizing that the microcatheter had entered a perforating artery rather than the intended A2 segment, retrieval was attempted; however, the device did not move in either direction, suggesting entrapment.

Digital subtraction angiography (DSA) confirmed the entrapment of the microguidewire in a perforating artery near the anterior communicating artery aneurysm. Several attempts were made to carefully remove the microguidewire over approximately 10 min. However, the roadmap image revealed displacement of the previously inserted coil mass by a few millimeters, indicating traction-related vascular movement (Figure 1(b)). Considering the risk of avulsion injury, further forceful attempts were avoided.

As the original microcatheter was considered to be wedged, an additional Excelsior SL10 microcatheter was positioned near the site of entrapment, and IA nimodipine (Nimotop S, 10 mg/50 mL, Bayer Vital GmbH GB Pharma, Germany) was infused. After 15 min and a total dose of 2.3 mg, the microguidewire was successfully retracted. Both the microcatheter and microguidewire were completely removed (Figure 1(c)), and subsequent DSA showed no contrast leakage, indicating the absence of active bleeding.

After IA nimodipine infusion, the patient experienced a transient drop in blood pressure (from 88/47 to 70/44 mmHg) and heart rate (from 74 to 64 bpm), which were promptly managed by the anesthesiologist with intravenous phenylephrine (0.2 mg) and ephedrine (10 mg). The planned stent-assisted coil embolization was completed without complications, and postprocedural computed tomography confirmed the absence of hemorrhage (Figure 1(d)). The patient remained asymptomatic, and neurological examination revealed no deficits.

The Institutional Review Board of Chungbuk National University Hospital approved the retrospective review of the patient’s medical records (IRB No.: 2024-10-003, 10 October 2024). Informed consent was obtained from the patient for publication of the case details. The reporting of this study conforms to the Case Report (CARE) guidelines. ⁸

Discussion

Hemorrhagic complications during the endovascular treatment of cerebral aneurysms are often caused by perforation or rupture of the aneurysm itself.^2,3 However, perforations involving normal cerebral arteries due to microcatheters or microguidewires have also been reported.^2,3 A few reports have highlighted the risk of avulsion injury caused by microguidewire entrapment, particularly in perforating arteries.^6,7 These complications can occur during complex neurointerventional techniques, such as stent-assisted coil embolization or the use of multiple microcatheters, which often involve device exchanges during stenting or angioplasty procedures.^3,6,7

Forceful pulling on an entrapped microguidewire can cause avulsion injury to the perforator, ⁶ which is a serious complication. Although perforation caused by a microguidewire may appear less catastrophic than rupture of an aneurysm sac per se, the clinical outcome can still be severe, particularly in patients pretreated with dual antiplatelet agents, a common practice in neurointerventions. ² Previous case reports suggest that leaving an irretrievably entrapped microguidewire in place may be the safest option.^6,7 However, this approach is unsatisfactory for both the neurointerventionist and patient.

Reports of successful and safe retrieval in cases of microguidewire entrapment are lacking; however, the use of various vasodilating agents has been attempted as management strategies. We selected IA nimodipine based on its favorable safety profile and established role in the management of cerebral vasospasm after subarachnoid hemorrhage (SAH), as endorsed by the 2012 American Heart Association/American Stroke Association and 2013 European Stroke Organization guidelines.^9,10 Among various vasodilators, nimodipine is preferred owing to its selective action on cerebral arteries and lower neurotoxicity. Verapamil, a non-dihydropyridine calcium channel blocker, has also been used successfully for IA infusion, particularly in diffuse vasospasm.^11,12 Milrinone, a phosphodiesterase-3 inhibitor, has been increasingly utilized in the treatment of cerebral vasospasm,^6,7 particularly in refractory cases; however, a recent study in patients with SAH-related vasospasm suggested that milrinone may be less effective than calcium channel blockers when used alone. ¹³ Papaverine, although used historically, is now discouraged owing to its neurotoxic potential, including brainstem dysfunction and seizures. Such concerns are reflected in the 2012 American Heart Association/American Stroke Association guideline. ⁹ Additionally, nicardipine has emerged as an effective agent in IA protocols owing to its cerebrovascular selectivity and has been used in both monotherapy and combination approaches. ¹³

Although overt angiographic vasospasm was not observed, localized spasm triggered by mechanical irritation during microguidewire advancement was suspected. We infused 2.3 mg of IA nimodipine over 15 min. Although the original microcatheter may have limited distal flow due to wedging, we hypothesized that local delivery near the affected vessel induced smooth muscle relaxation at the perforator entry, reducing wall tension and facilitating retrieval. Despite the temporal association between nimodipine infusion and successful release, spontaneous or passive resolution cannot be ruled out. Thus, the causal effect of nimodipine should be interpreted with caution.

Although standardized protocols for IA administration are lacking, common practice involves slow infusion at a rate of 1–4 mg/h, with a total dose of 1–3 mg per treated vessel, depending on clinical response and hemodynamic tolerance.^11,14 The European Stroke Organization guideline endorses the use of intravenous nimodipine at a rate of 1–2 mg/h for the treatment of vasospasm after SAH. ¹⁰ However, intravenous infusion delivers the drug systemically and is more likely to cause systemic hypotension and related side effects. In contrast, IA nimodipine allows for localized drug delivery directly to the cerebral vasculature, which may minimize systemic exposure and reduce the risk of adverse hemodynamic effects. Although further studies are required to confirm its efficacy, administering an adequate dose of IA vasodilator with careful hemodynamic monitoring while attempting retrieval with extreme caution may offer a practical and reasonable approach (Figure 2).

Figure 2.

Management strategies for entrapment of the microguidewire in a perforating artery. (a) Entrapment of the microguidewire during an endovascular procedure. (b) Forcefully pulling on an entrapped microguidewire can result in avulsion of the perforator. (c) Leaving the microguidewire in place and cutting it at the femoral puncture site may be considered as a viable option and (d) administering intra-arterial nimodipine with cautious retrieval offers a practical strategy.

Microguidewire entrapment is most likely to occur in the perforating arteries. The microguidewires commonly used in neurointerventions are 0.356 mm (0.014 in) in diameter, similar in size to the intracranial perforating arteries, which generally range from 0.175 to 0.469 mm. ¹⁵ For example, the perforators of the anterior communicating artery are approximately 0.175 mm in diameter, and the lenticulostriate artery measures approximately 0.469 mm. Notably, the recurrent artery of Heubner has the largest diameter among the perforating arteries, measuring 0.668 mm. This similarity in size increases the potential for microguidewire entrapment within small vessels.

Entrapment may result not only from vasospasm but also from tight wedging of the microguidewire within the vessel. Laser-cut microguidewires such as the Synchro 14, with their sharper, spear-like tip, are known to carry a higher risk of entrapment compared with microguidewires with smooth or screw-like tips such as the Transend microguidewire. ⁶ Therefore, special caution is necessary during procedures involving aneurysms in regions such as the basilar artery or anterior communicating artery. With the growing trend of performing mechanical thrombectomy for distal medium-vessel occlusions, distal cortical branches may also be at risk of microguidewire entrapment. Additionally, the resolution limitations of DSA, which can only resolve vessels approximately 0.08–0.2 mm in diameter, may hinder the detection of smaller yet clinically significant perforators. ¹⁶

Conclusion

Microguidewire entrapment in a perforating artery during endovascular treatment can lead to fatal avulsion injury if not properly managed. It is crucial to avoid forceful pulling of the microguidewire and instead use sufficient doses of IA nimodipine to facilitate safe retrieval.