Accidental guide catheter fracture in mechanical thrombectomy

Abstract

Endovascular thrombectomy is now the standard of care for large vessel occlusion stroke. The aim is to achieve rapid and complete recanalisation while avoiding complications. Apart from the conventional complications of neurointerventional procedures, mechanical thrombectomy has its unique set of complications, inherent to the disease pathophysiology. We describe an unusual complication of catheter fracture and subsequent distal embolisation into the cerebral vasculature, which was noticed 24 hours after the procedure. Due to a lack of clinical consequences, we decided to manage it conservatively. The patient died within the following few days from respiratory complications unrelated to the stroke or the endovascular thrombectomy procedure. Consequently, we were able to retrieve the fractured segment and carry out histopathological analysis, which helped us to identify exactly its origin from the guide catheter. We believe that systematic reporting and database compilation of such device-related complications will aid in the design and development of neurointerventional devices in the future.

Background

Endovascular thrombectomy (EVT) is an established treatment for acute ischaemic large vessel occlusion stroke supported by class A, level I evidence.¹ The two accepted treatment strategies are stent retriever-based thrombectomy or aspiration thrombectomy, referred to as ADAPT.² These treatment options can be used alone or in combination.³ Some of the important limitations of the procedure are recanalisation failure, distal embolisation to target or new vessel territory, risk of symptomatic or asymptomatic intracerebral haemorrhage and procedure-related complications.⁴ Our usual protocol for mechanical thrombectomy is ADAPT, in which we perform aspiration thrombectomy first.⁵ If there is failure of aspiration, then we combine stent retriever-based thrombectomy with aspiration. We hereby describe a unique complication noticed 24 hours after the thrombectomy procedure, which has never been described before in diagnostic or therapeutic neurointerventional procedures.

Case presentation

An octogenarian patient, ambulant and independently performing usual activities at baseline, with diabetes mellitus type II, hypertension and cardiac arrhythmia, on regular medications, presented to the emergency department with aphasia and right hemiplegia within 30 minutes. The patient’s National Institutes of Health stroke scale (NIHSS) score at admission was 15. Neuroimaging revealed a hyperdense left middle cerebral artery (MCA) sign and early ischaemic changes in the insular region with an Alberta Stroke Program Early CT Score (ASPECTS) of 9 (Figure 1a and b). Prior anticoagulant use was a contraindication to intravenous thrombolysis, hence the patient was immediately taken to the angiography suite for endovascular treatment. General anaesthesia was given as the patient was aphasic, and deemed unsuitable for the procedure under conscious sedation. A 8 French (F) short sheath (Radiofocus, Terumo; Europe NV, Belgium) was inserted in the right femoral artery followed by the insertion of a 6 F 90 cm NeuronMax guide catheter (Penumbra, Alameda, USA). The guide catheter was coaxially advanced over a 6 F Penumbra select catheter (Penumbra) into the left internal carotid artery (ICA). A diagnostic angiogram revealed occlusion of the proximal M1 MCA and ipsilateral A2 anterior cerebral artery (ACA) (Figure 1c). Therefore, through the guide catheter located in the left cervical ICA, a Sofia 5 F (Microvention, California, USA) was navigated into the proximal MCA and two attempts at aspiration thrombectomy with manual aspiration were performed, however they failed.

Figure 1.

(a) and (b) Non-contrast computed tomography scan showing dense middle cerebral artery (MCA) sign without early signs of ischaemia; (c) digital subtraction angiography of left carotid artery anteroposterior view showing an occlusion of M1 MCA and A2 anterior cerebral artery (ACA) (red arrow); (d) M1 MCA recanalisation with occluded A2 ACA; (e) final angiogram with thrombolysis in cerebral infarction (TICI) 3 flow.

Following failure of aspiration, the decision was made to perform a stent retriever-based thrombectomy. With the Sofia catheter placed in the carotid bifurcation, a Pro 18 microcatheter (Stryker Neurovascular, Fremont, CA, USA) was advanced into the M2 passing across the thrombus. Contrast injection confirmed the placement and patency of the distal M2. Through the Pro 18 microcatheter, a stent retriever (Trevo, 4 × 20 mm; Stryker Neurovascular) was deployed from the M2 to the M1 across the thrombus. With the stent retriever anchored in the MCA, the microcatheter was removed. After 3–5 minutes, the stent retriever along with the aspiration catheter were withdrawn under continuous aspiration. Complete recanalisation of the MCA was noted on the follow-up angiogram, with persistent A2 ACA occlusion (Figure 1d).

In a second step, the microcatheter was advanced into the distal A2 across the thrombus and a 3 × 20 mm stent retriever (ERIC; MicroVention, California, USA) was placed. The procedure protocol was followed as described above and recanalisation of the A2 was achieved in a single pass (Figure 1e). Post-procedure angiography revealed thrombolysis in cerebral infarction (TICI) 3 flow without any evidence of spasm, dissection, distal embolisation or contrast leakage. Used catheters and wires were disposed of. The patient was kept on mechanical ventilation and was transferred to the stroke unit. On the next day a routine non-contrast computed tomography (CT) scan of the head was performed. Among ischaemic changes, it showed an incidental ‘ring-shaped’ foreign body metallic density located at the distal end of the M1 MCA (Figure 2a). A wide window CT scan showed a resemblance to the radiopaque marker band of the catheter. A retrospective analysis on the unsubtracted digital subtraction angiography (DSA) showed the same ‘ring-shaped’ radio opacity at the carotid bifurcation at the end MCA recanalisation, which had floated to the distal MCA at the end of the procedure with A2 ACA recanalisation, without any flow reduction or delay. A CT angiogram was performed to confirm these findings (Figure 2b and c). The patient showed neurological improvement with antigravity movement in her right arm and leg. However, she remained intubated because of respiratory complications. The decision was made to treat her conservatively with antiplatelets without any attempt at endovascular extraction or open surgical removal of the ring. In the following days, regular non-contrast CT scan of the head revealed no increase in the size of the infarct.

Figure 2.

Postoperative, retrospective analysis and autopsy findings: (a) 24-hour control computed tomography (CT) scan yielded a foreign body signal at the middle cerebral artery (MCA) bifurcation; (b) CT angiogram foreign body signal with patent MCA; (c) lateral view with foreign body at the MCA bifurcation; (d) postmortem dissection showing a broken piece from the NeuroMax guide catheter at the MCA bifurcation; (e) fractured piece of the NeuroMax catheter shaft.

During the hospital stay, the patient developed pneumonia and died from acute respiratory distress syndrome (ARDS). The patient underwent an autopsy and we were able to recover the ring-shaped piece from the MCA (Figure 2d and e). As the ring appeared larger in size than the microcatheter and aspiration catheter on DSA angiogram as well as visual inspection, we assumed that the portion detached from the guide catheter. It was sent for analysis to Penumbra Inc. The analysis confirmed that this was a detached piece from the shaft of the NeuronMax, with intact marker band along with its lamination. Penumbra did retrospectively inspect the device lot for any discrepancies in catheter design, quality and tensile strength, and did not reveal anything remarkable.

Discussion

Endovascular stroke treatment is an emergency neurointerventional procedure in which the main goal is the rapid recanalisation of the occlusion, as safely as possible. With growing evidence, the frequent use of EVT and concomitant complications is expected in the future. Some of the important EVT procedure-related complications include reperfusion injury, thromboembolisation to previously affected as well as unaffected territories, access site complications, vasospasm, arterial dissection and device-related complications. The rate of complications varies according to the clinical scenario and patient-related factors. Data from various randomised controlled trials show that the risk of clinically significant complications from mechanical thrombectomy is up to 15%.⁴ Therefore, both neurointerventionists and the stroke team should be aware of the risk factors, strategies for prevention and management of these complications.

The usual working set-up for mechanical thrombectomy is the use of either a 6 or 8 F guiding sheath or a large bore (8 or 9 F) balloon guide catheter. In stent retriever-based thrombectomy, with the help of a microwire and microcatheter a stent is deployed across the thrombus, while in aspiration thrombectomy a 5 F or 6 F aspiration catheter is placed just proximal to the thrombus. Device-related complications can be related to the thrombectomy device itself or related to auxiliary devices such as guide catheters and wires. Device failure (stent detachment, displacement or fracture) is often reported with EVT, with incidence rate of 0.66–3.9%.^6,7 Apart from failure of recanalisation it can cause thrombus propagation and stroke progression.

Another frequently reported endovascular device-related complication is coil dislodgement, embolisation or stretching. Murayama et al. have reported a 0.5% risk of coil migration.⁸ Catheter fracture and wire detachment, on the other hand, are less commonly reported in the neuroendovascular literature.⁹ The removal of embolised material by endovascular extraction using Snare, Alligator or Thrombectomy stents with or without antiplatelets/anticoagulation is currently the mainstay of treatment. If removal of embolised material is not possible, fixation against the artery by deploying a stent is an alternative strategy that can be employed. Also, in the case of endovascular failure, open surgical extraction has been described in the literature.⁹

To the best of our knowledge one case of catheter fracture (aspiration catheter) has previously been described in EVT cases, in which successful removal of the fractured segment was possible.¹⁰ Our case was unique in that the broken piece was from the guide catheter, which was also confirmed on histopathological analysis. The piece we recovered was very neat as well as clean, without any obvious traction points or irregularity along the surface. We assume that the sheath got separated at one of the distal transition zones in the region of the marker band as the neurovascular anatomy was straightforward, and throughout the procedure there was no undue traction. It will be interesting to see and compile data on such unusual device-related complications, which will help us in the design and development of endovascular devices in the future.

Learning points/take home messages

• One should always keep in mind the possibility of atypical device- related complications. A careful analysis of angiograms at the end of the procedure is necessary for early detection and if necessary emergent treatment of complications.

• Device-related complications are an avoidable part of neurointerventional procedures, particularly more common in stroke. Regular and systematic reporting of such complications is necessary for academic as well as research purposes.

• Knowledge about the techniques of embolised material removal are imperative in the practice of neurointervention.

Declaration of conflicting interests

The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The authors received no financial support for the research, authorship, and/or publication of this article.