key: cord-1040381-ej18f7g5
authors: Ali, Ali B.; Hui, Samuel H.; Mouawad, Nicolas J.
title: Mechanical Thrombectomy of Symptomatic Carotid stenosis with free-floating thrombus in COVID-19 Using Transcarotid Artery Revascularization
date: 2021-10-01
journal: J Vasc Surg Cases Innov Tech
DOI: 10.1016/j.jvscit.2021.09.001
sha: 3cfb55b6ff06e129a20bdf6df736fc8d36bb81fe
doc_id: 1040381
cord_uid: ej18f7g5

Carotid Stenosis with free floating thrombus is associated with ipsilateral neurological deficit as a result of cerebrovascular accident or an ischemic stroke. Arterial thrombosis and thrombus instability have shown an association with COVID-19. Immediate evaluation is essential to asses and prevent thrombus propagation. Traditionally, Transfemoral stenting is performed as a minimally invasive surgery. We hereby describe the successful use of Transcarotid arterial revascularisation (TCAR) on retrograde flow, aspiration of the thrombus utilizing penumbra mechanical thrombectomy, and TCAR stenting in a COVID-19 confirmed case.

Free-floating thrombus (FFT) is a relatively rare event; it usually presents as an acute 2 emergency and demands prompt attention as delay exposes patients to devastating neurological 3 complications. The current and definitive management of FFT is still controversial. Surgical 4 outcomes with carotid endarterectomy (CEA) and medical management with anticoagulation 5 have revealed similar outcomes 1 . COVID-19 thromboembolic association has been described in 6 the literature through mechanisms of hypoxia, inflammation, and diffuse intravascular 7 coagulation 2 . Transcarotid Artery Revascularization (TCAR) is established as a method of 8 carotid revascularization currently indicated in high-risk patients and has been shown to have a 9 low risk of perioperative thrombus embolization 3 . Mechanical thrombectomy (MT) alone was 10 reported to have risks of thrombus fragmentation and embolization, especially in an unstable 11 A repeat head CT on day 2 revealed subarachnoid haemorrhage (SAH); neurological 3 surgery recommended to continue antiplatelet. Regarding the COVID-19 status, the patient's 4

SpO2 was between high 80s-low 90s on 4L O2. Patients had elevated D-dimer and COVID-19 5 markers (Table 1) . 6

We proceeded with TCAR flow reversal, MT using Penumbra, and stent placement rather 7 than traditional CEA due to patient's high risk and proximal thrombus location, or medical 8 therapy due to concerns of anticoagulation regarding the SAH and the risks of hemorrhagic 9

transformation. The neurology and neurosurgery teams agreed to the plan after repeat head CT 10 confirmed stable imaging and accepted procedural anticoagulation as long as protamine reversal 11 is achieved. Nasotracheal intubation, mandibular subluxation, and even lateral mandibulotomy 12

were discussed due to the proximal location of the FFT; however, taking into account the current 13 COVID-19 status and acute stroke, it was decided to consider percutaneous MT with 14 neuroprotection using flow reversal technique. The patient went to theatre after confirming the 15 safety of surgery with the multi-disciplinary team, 4 days after his presentation. Informed 16 consent was obtained. 17 1 changes were identified during carotid clamping or reversal of flow compared to baseline. 2 A CAT-8 MT catheter (Penumbra, Alameda, CA) was then advanced through the 8-3

French arterial sheath and suction thrombectomy was started while on flow reversal was 4 maintained. The catheter was then advanced in antegrade fashion through the ICA. This process 5 was performed 3 times, and a large flow channel was obtained, an angiogram was performed 6 post-MT suction ( Figure 3B ). The distal internal carotid artery was engaged with a 0.014-inch 7 wire, and the ICA stenotic part was ballooned using a 5.5-mm balloon, followed by stenting 8

with an ENROUTE 9mm X 40 mm stent (Silk Road Medical, Sunnyvale, CA). The The extrapulmonary manifestation of COVID-19 has been previously described in the 1 literature. Major manifestations include venous and arterial thromboembolism causing acute 2 ischemic stroke 2, 5, 6 . 3

Management of FFT is still understudied and no set guidelines regarding timing, best 4 approach, or intervention exist. TCAR has been shown to carry low incidence of perioperative 5 strokes and cranial nerve injuries. The 2 ROADSTER studies 3, 7 , single-arm clinical trials, 6 demonstrated low perioperative stroke risk for TCAR both below 2% with lower risk of cranial 7 nerve injuries than reported in the literature for CEA. Multiple studies 8-10 have shown similar 8 perioperative stroke risk of TCAR compared to the traditional CEA, with lower myocardial 9 infarction risk despite the higher baseline comorbidities of the TCAR patients, however, 10 compared to Transfemoral Carotid Artery Stenting (TF-CAS), the outcome of TCAR was 11 significantly better with significantly shorter procedure time. 12

Alternative interventions were discussed such as TF-CAS, however, we were 13 uncomfortable proceeding for two reasons (1) this technique requires traversing the unstable FFT 14 to deploy a distal embolic protection device (2) placing the stent without adjunctive 15 thrombectomy in our estimation would "cheese grate" the thrombotic material; with TCAR flow 16 reversal, these risks are mitigated. Additionally, in a case series 11 

Free-floating thrombus of the carotid artery: Literature review and case reports

Incidence of thrombotic complications in critically ill ICU patients with COVID-19

ROADSTER multicenter trial of transcarotid stenting with dynamic flow reversal

Risk of Thrombus Fragmentation during Endovascular Stroke Treatment

Prevalence of venous thromboembolism in patients 14 with severe novel coronavirus pneumonia

Outcomes of

Transcarotid Artery Revascularization and Carotid Endarterectomy at a Single Institution

TransCarotid Revascularization with Dynamic Flow reversal versus Carotid 5

Endarterectomy in the Vascular Quality Initiative Surveillance Project

Stroke and mechanical

thrombectomy in patients with COVID-19: technical observations and patient characteristics

Stentriever thrombectomy with distal protection device 10 for carotid free floating thrombus: a technical case report

Mechanical Thrombectomy of Symptomatic Acute Carotid Stent 12

Use of Transcarotid Artery 15

Revascularization to Treat Symptomatic Carotid Artery Stenosis Associated with Free-Floating 16

mg/dL (High) ESR 42 mm/hour (High) CRP 4.9 mg/dL, 49 mg/L (High) INR 1.48 (High) PTT

Pg/ml (High) Procalcitonin 0.08 ng/ml (Normal) Platelet Count 441X10 3 /uL