Emergency carotid endarterectomy with stent retrieval in a patient with stent migration following failed carotid artery stenting

Abstract

Carotid artery stenting (CAS) has become a favoured alternative to surgical carotid endarterectomy (CEA) in select cases of critical internal carotid artery (ICA) occlusion. However, complications such as stent migration or entrapment can occur, necessitating prompt diagnosis and intervention. We present a case of a 75-year-old diabetic male who underwent CAS for recurrent presyncope at a private hospital, and during the procedure of CAS the stent was migrated and its proximal part was impacted in the critically narrowed part of the ICA. The operating team failed to retrieve the stent and due to the unavailability of a vascular surgeon at their center, the patient was referred to us for stent retrieval and CEA. The patient underwent emergency carotid stent extraction and CEA with autologous saphenous vein graft patch reconstruction of ICA. His postoperative course was uneventful and the patient was discharged home on the 5th postoperative day. This case highlights the significance of multidisciplinary decision-making and prompt intervention in optimizing patient outcomes.

Introduction

Carotid artery stenting (CAS) has emerged as a safe and less invasive alternative to surgical carotid endarterectomy (CEA) for the management of severe internal carotid artery (ICA) occlusion in selected patients [1]. It involves intravascular catheter-mediated balloon dilatation of the stenosed segment of the carotid artery and placement of a stent to establish and maintain forward blood flow under fluoroscopy guidance. It is important to note that the decision to undergo CAS versus CEA depends on various factors like severity and level of stenosis, plaque morphology, aortic arch anatomy, and medical condition of individual patients. CAS-related complications are classified as cervical (plaque prolapse, acute stent thrombosis, improper deployment of a stent, carotid dissection, and cerebral protection device entrapment), intracranial (embolism, hyper-perfusion syndrome, and contrast encephalopathy) and vascular access site related [2, 3]. With the increase in carotid artery intervention in complex cases, complications for this procedure are expected to rise.

Case report

A 75-year-old diabetic male presented to the emergency with history of endovascular intervention for recurrent presyncope 12 h back at a private hospital. The patient was an active tobacco smoker with no history of cerebrovascular accident in the past and did not have any neurological deficits on examination. Medical records were evaluated and the case was discussed with the treating interventionist telephonically. Diagnosis of under-deployed and impacted stent in right ICA was made. Computed tomography (CT) angiography (Fig. 1a, b) was done to anatomically delineate the carotid lesion and impaction site of the stent to plan surgical intervention. Angiogram revealed 90% stenosis in around 3-cm segment of proximal right ICA with an impacted stent (WALLSTENT Boston Scientific 8 mm/29 mm) in situ with a complete circle of Willis (Fig. 1c, d). Interventional Radiology team opinion was taken after CT angiogram, for stent retrieval reattempt. However, due to complexity of lesion, they advised for open stent retrieval and CEA. The patient underwent stent extraction followed by CEA under general anesthesia by right latero-cervical approach (Fig. 2a, b). As on pre-operative CT angiogram, Circle of Willis was complete and carotid occlusion was near complete; hence, shunt was not used and surgery was done under near infrared spectroscopy (NIRS) monitoring. ICA was reconstructed by an autologous saphenous vein graft patch. Carotid cross-clamp time was 19 min and an endarterectomy was done from right ICA and external carotid ostia (Fig. 2c, d). The patient recovered well after surgery and was discharged on post-operative day 5 in an asymptomatic state. At 3 months follow-up, the patient did not report any neurological symptoms and CT angiography (Fig. 3a, b) demonstrated well-reconstructed ICA and normal opacification of distal vasculature (Fig. 3c, d).

Fig. 1.

The coronal (a) and sagittal (b) CT angiogram images with 4 mm maximal intensity projection shows migrated carotid stent (WALLSTENT, Boston Scientific) with the proximal end of stent showing severe tapering and ending in the cervical ICA (white arrow). The volume rendered image (c) shows the conical tapering of the stent. The axial CT angiogram image (d) shows normal contrast opacification within the stent. (CT, computed tomography; ICA, internal carotid artery)

Fig. 2.

Intraoperative images (a), stent extraction (b), carotid endarterectomy (c), reconstructed ICA, and (d) endarterectomy specimen. (ICA, internal carotid artery)

Fig. 3.

The post-operative follow up angiogram after 3 months. The coronal (a) and sagittal (b) CT angiogram images show surgically reconstructed right proximal ICA (white arrow). The volume rendered image (c) and axial CT angiogram (d) confirms the reconstruction of ICA with normal opacification of distal vasculature. (ICA, internal carotid artery; CT, computed tomography)

Discussion

Carotid artery stent migration or entrapment represents a serious concern in the realm of vascular interventions, often arising from various underlying factors. Improper placement of the stent during the procedure, inadequate sizing relative to the vessel’s dimensions, or the presence of anatomical complexities such as tortuosity or severe stenosis can predispose patients to these complications [4]. Therefore, meticulous assessment and thorough pre-procedural evaluation are paramount when considering CAS.

In the context of CAS, it is crucial to carefully select patients and lesions to achieve optimal outcomes and minimize the likelihood of device retention incidents. Lesions with high degree of calcification, tortuous vessel anatomy, or severe stenosis present challenges during stent deployment and increase the risk of complications [4, 5]. Thus, practitioners must exercise caution and consider alternative treatment options for such cases to mitigate adverse outcomes.

Management of migrated carotid stents typically involves a systematic approach that begins with comprehensive assessment and imaging studies to determine the extent of stent migration and its potential impact on vascular patency and cerebral perfusion. Depending on the severity of the migration and associated complications, additional interventions may be required, ranging from simple repositioning maneuvers to more complex stent retrieval procedures. Prompt detection and intervention are crucial in preventing further complications and preserving vascular integrity [5].

In our particular case, the first challenge was to remove the stent without causing any damage to the healthy carotid artery intima. After that, we had to perform a complete endarterectomy of the ICA in an emergency, where the risk of complications was quite high. As the patient was operated within 24 h of primary intervention, therefore the stent was not impacted in intima and was retrieved with ease. Upon examining the excised specimen, we discovered that there was almost complete blockage at the proximal part of the ICA, while distally, the ICA was of a good size. After discussing the situation with our interventional radiology team, we retrospectively analyzed that this case was not suitable for CAS, and secondly, the size of the stent used was only 8 mm, which seemed to be undersized, leading to stent migration.

Recent guidelines from the European Society of Vascular Surgery (ESVS) [6] underscore the importance of a multidisciplinary approach in managing carotid occlusive disease. This collaborative approach involves input from vascular surgeons, interventional radiologists, neurologists, and other specialists to determine the most appropriate treatment modality for each patient. While CEA remains a class I recommendation for symptomatic high-grade carotid stenosis patients, CAS is typically reserved for individuals deemed at high surgical risk due to comorbidities or anatomical considerations.

Conclusion

The importance of proper patient selection for CAS cannot be overemphasized. The role of the vascular surgeon is paramount in determining the feasibility of CAS and in the management of its potential complications. By correct patient selection and adopting a multidisciplinary approach, clinicians can optimize patient outcomes and minimize the risks associated with carotid artery interventions.

Author contribution

DM and SP prepared primary draft. ST and AM contributed in image retrieval and editing. PC and AKS contributed in revision of draft and all authors approved the final versions.

Funding

None.

Availability of data and material

Not applicable.

Code availability

Not applicable.

Declarations

Conflict of interest

The authors declare no competing interests.

Ethics approval

As this is a single case study ethical waiver was granted by the institutional ethical committee (IEC AIIMS Jodhpur).

Consent to participate

Informed consent was taken from the patient for the study and publication.