Unstable Carotid Artery Thrombus in a Patient With COVID-19 Infection.

We present a case of an unvaccinated, 43-year-old African American female patient with COVID-19 infection and clinical evidence of a left hemispheric stroke. A non-occlusive thrombus with a radiographic target lesion was identified on computed tomography angiography (CTA). A multi-disciplinary discussion regarding concern for embolization was provided due to its unstable nature, as well as evidence of recent stroke. Given her acute COVID-19 infection, symptomatology, and radiographic findings, it was concluded that the etiology of her stroke appeared most consistent with a hypercoagulable-related embolism rather than an atheroembolic event. The patient underwent left carotid artery thrombectomy with bovine patch angioplasty. Operative findings included: left carotid thrombus, minimal plaque after evacuation of the thrombus, and a small proximal internal carotid artery diameter. Given concern for stenosis with primary repair a bovine pericardial patch angioplasty was performed. We present a paradigm for extracranial carotid thrombectomy with therapeutic anticoagulation for COVID-related spontaneous arterial thrombosis.

Multiple Sites of Arterial Thrombosis in A 35-Year Old Patient after ChAdOx1 (AstraZeneca) Vaccination, Requiring Emergent Femoral and Carotid Surgical Thrombectomy.

BACKGROUND: Vaccine Induced Thrombotic Thrombocytopenia (VITT) is a rare complication following ChAdOx1 (AstraZeneca) vaccination. Venous thrombosis in unusual sites such as splachnic or intracranial thrombosis, is the commonest manifestation. CASE REPORT: We report a 35-year-old male patient who presented with acute left leg ischemia and thrombocytopenia 11-days after vaccination requiring emergent thrombectomy. During work-up, a localized thrombus was detected in the left carotid bifurcation mandating carotid thrombectomy. Localized right iliac thrombus causing a non-limiting flow stenosis was treated conservatively. The platelet aggregating capacity of patient's plasma was confirmed in a functional assay, thereby establishing VITT. CONCLUSION: To the best of our knowledge this is the first case presenting multiple arterial thromboses requiring surgical treatment after ChAdOx1 vaccination.

Predicting Clinical Outcome After Mechanical Thrombectomy: The GADIS (Gender, Age, Diabetes Mellitus History, Infarct Volume, and Current Smoker [corrected]) Score.

OBJECTIVE: To investigate predictive factors and develop an outcome assessment tool to determine clinical outcome after endovascular mechanical thrombectomy (EMT) in patients presenting with large vessel occlusion (LVO). METHODS: A retrospective analysis was carried out of a prospective cohort of patients presenting with LVO who underwent EMT after adoption of an expanded time window of ≤24 hours. Final cerebral infarction volume (CIV) after EMT was estimated using magnetic resonance imaging segmentation software. Stepwise linear regression models were used to identify factors that determined clinical outcome and to develop a predictive scale. RESULTS: Ninety patients underwent EMT over 19 months (68 within 6 hours and 22 between 6 and 24 hours). Clinical outcome determined using modified Rankin Scale (mRS) score at discharge and 3 months was no different among these subcohorts. A threshold of 16.99 mL of CIV, using the Youden index, resulted in a sensitivity of 90.5% and specificity of 58.1% for predicting mRS score of 0-2. A regression model identified gender, age, diabetes mellitus status, CIV, and smoking status as outcome determinants, which were used to develop the GADIS (Gender, Age, Diabetes Mellitus History, Infarct Volume, and Sex) scoring system to predict good clinical outcome. Using the GADIS score, <6 predicted mRS score 0-2 at discharge with a sensitivity of 83.3% and specificity of 80.6%. CONCLUSIONS: The GADIS score for patients with LVO-related acute ischemic stroke includes CIV after EMT and helps in early short-term prognostication. It is not intended to predict preintervention patient selection or outcome prediction.

Investigation of Radiation Exposure of Patients with Acute Ischemic Stroke during Mechanical Thrombectomy. / Untersuchung der Strahlenexposition des Patienten mit akutem ischämischem Schlaganfall während der mechanischen Thrombektomie.

PURPOSE: In radiological interventions, the skin is the most exposed organ. The aim of this study was to investigate the local dose exposure and the resulting risk of deterministic radiation effects for patients who underwent mechanichal thrombectomy. MATERIALS AND METHODS: The examination protocols of 50 consecutive stroke patients who underwent mechanical thrombectomy from September 2016 to April 2017 were evaluated in this study. All procedures were performed on a biplanar angiographic suite. The local skin equivalent dose H P(0.07) was calculated retrospectively using the recorded radiation data and previously measured conversion factors. The in-vitro determination of the conversion factors was performed with a silicon semiconductor detector on the surface of an Alderson-Rando head phantom depending on the radiation quality. RESULTS: Vessel occlusion was located in the M1 and M2 segments of the cerebral artery media (n = 32), the internal carotid artery or carotid-T (n = 12) and the basilar artery (n = 6). The fluoroscopy times ranged from 5.7 minutes to 137.3 minutes with an average value of 39.5 ±â€Š4.1 minutes. The determined skin equivalent dose values ranged from 0.16 ±â€Š0.02 Gy to 4.80 ±â€Š0.51 Gy, with the mean value being 1.00 ±â€Š0.14 Gy. In 3 out of 50 cases (6 %), the threshold value for skin reactions of 3 Gy published by the German Radiation Protection Commission was exceeded. A further 15 patients (36 %) were exposed to a dose of 1-3 Gy. The highest dose values were achieved during long procedures with occlusions in the posterior circulation and carotid occlusions. In addition, a local dose reference level of 1.24 ±â€Š0.15 Gy could be determined for the skin equivalent dose in mechanical thrombectomies for our center. CONCLUSION: Even during a modern neuroradiological intervention, such as mechanical thrombectomy, radiation doses to the patient are produced and can lead to deterministic radiation damage to the skin in approximately 6 % of cases. Systematic monitoring of local dose quantities, such as H P(0.07), seems appropriate. Possibilities for recording and reducing the local dose load should be developed by the interventional teams in cooperation with a medical physics expert. KEY POINTS: · In 64 % of the thrombectomies the skin equivalent doses were in the harmless range (< 1 Gy).. · In 6 % of the patients higher H P(0.07) values were determined, which can lead to deterministic radiation damage to the skin.. · To avoid deterministic damage during neurointerventions, H P(0.07) should be recorded (combined measuring chambers).. · For longer interventions, precautions should be taken to reduce the radiation dose.. CITATION FORMAT: · Bärenfänger F, Block A, Rohde S. Investigation of Radiation Exposure of Patients with Acute Ischemic Stroke during Mechanical Thrombectomy. Fortschr Röntgenstr 2019; 191: 1099 - 1106.

Posterior cerebral artery giant aneurysm associated with bilateral internal carotid artery occlusion in a Klippel-Trenaunay syndrome patient: a case report.

We experienced an extremely rare case of a giant P1-P2 partially thrombosed aneurysm associated with bilateral ICA occlusion in a Klippel-Trenaunay syndrome patient. In our experience, direct surgical clipping via a pterional approach is generally favored for aneurysms located in the junction of the P1-P2 segments, even if they are giant.

Recurrent thrombosis after carotid endarterectomy secondary to activated protein C resistance and essential thrombocytosis: A case report.

RATIONALE: Thrombosis is a major cause of morbidity in the perioperative period. Although many risk factors are known, activated protein C resistance is a prominent risk for thrombosis. Activated protein C resistance frequently occurs with recurrent thromboembolism. PATIENT CONCERNS: A 59-year-old Korean woman patient with hypertension was admitted due to dysarthria and left side motor weakness. DIAGNOSIS AND INTERVENTIONS: Magnetic resonance imaging showed subacute cerebral infarction with right frontoparietal lobe and stenosis at the right internal carotid artery. She underwent right carotid endarterectomy under general anesthesia. However, recurrent thrombosis on postoperative day 1 was noted at patient's right carotid artery, which prompted emergency surgery. Additional preoperative laboratory review revealed findings for activated protein C resistance, low protein S activity, antinuclear antibody (>1:160), anti-cardiolipin IgM antibody (16.6), and thrombocytosis, Janus kinase and factor V Leiden mutations. At the intensive care unit, heparin was continually infused until postoperative day 12 and was then switched to warfarin. OUTCOMES: Patient was discharged at postoperative day 21 without any event. Patient had no signs of recurrence within the 3-year follow-up period, and she is still on oral warfarin and clopidogrel. LESSONS: Screening test for hypercoagulability can be used to identify patients at higher risk of postoperative complications. If hypercoagulability state is confirmed by laboratory testing, a suitable anticoagulant treatment plan should be made within the perioperative period.

Expanding the role of stent-retriever endovascular thrombectomy: a case series of free-floating thrombus.

Carotid artery free-floating thrombus (FFT) is a rare but clinically significant cause of embolic stroke. Treatment has historically been confined to carotid surgery or best medical therapy, with neither option proved to be superior. However, recent advancements in endovascular interventions have heralded a new age of innovative management strategies for vascular disease. We present three distinct cases of stroke secondary to carotid artery FFT, successfully treated with stent retriever endovascular thrombectomy.

Emergency Extracranial-Intracranial Bypass to Revascularize Salvageable Brain Tissue in Acute Ischemic Stroke Patients.

OBJECTIVE: To present an algorithm based on clinical and radiologic factors, including magnetic resonance imaging (MRI) perfusion/diffusion mismatch (PDM), for the indication of urgent cerebral bypass in patients with acute ischemic stroke. METHODS: Clinical and radiologic data of 8 consecutive patients undergoing urgent cerebral revascularization for acute ischemic stroke owing to occlusion of internal carotid or middle cerebral artery between 2012 and 2015 were analyzed. All patients either were ineligible for or failed first-line treatment with emergent endovascular revascularization. Indication for urgent bypass was based on clinical worsening and MRI PDM, indicating threat for stroke extension. Clinical outcome was measured using National Institutes of Health Stroke Scale and modified Rankin Scale before and after bypass surgery, at 3-month follow-up, and at last follow-up. RESULTS: All patients presented with clinical worsening after initiation of acute stroke treatment. Cerebral revascularization was performed 9.6 hours (SD 9.0) after clinical worsening. All patients had preoperative MRI PDM. No bypass complications, such as anastomosis failure or postoperative hemorrhage, occurred. MRI diffusion ratio before and after bypass was stable or improved in 7 patients and progressed in 1 patient without clinical worsening. MRI PDM and perfusion improved in all 4 patients who underwent postoperative MRI. Clinical outcome was favorable with a median improvement of 7 points on National Institutes of Health Stroke Scale and of 2 points on modified Rankin Scale at last follow-up. CONCLUSIONS: Based on an algorithm indicating salvageable brain tissue, cerebral revascularization can be safely performed in an emergency setting in a highly selected group of patients with acute ischemic stroke with favorable clinical outcome.

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

We report the clinical details, imaging findings and management of a 45-year-old man who presented with recurrent transient ischemic attacks due to carotid free floating thrombus. Free floating thrombus of the carotid artery is a very rare condition with a high risk of distal embolic shower. The optimal treatment options are debatable and include medical management, surgical thrombectomy and endovascular thrombectomy. We describe the use of a stentriever with filter protection in the management of carotid free floating thrombus as a novel treatment option.

Carotid free-floating thrombus in woman with meningioma: a case report and review of the literature.

OBJECTIVE: Several reports have previously described the coexistence of severe carotid artery disorders and brain tumors, in particular meningioma, mainly consisting of arterial occlusion or obstruction due to direct compression by tumor mass, with possible presence of transient neurological symptoms as well as complete cerebral infarction. Free-floating thrombus (FFT) is an uncommon condition, characterized by the presence of thrombotic material partially attached to the arterial wall with evidence of heartbeat associated floating. To our knowledge, our case represents the first report in literature about presence of internal carotid FFT in patient affected by meningioma. CASE REPORT: In this report, sharing singular images and videos of this uncommon condition, we present the first case of a right internal carotid artery FFT in a 59-year-old woman affected by meningioma, successfully treated with antiplatelet medication together with anticoagulation and high dose of statins. CONCLUSIONS: Our case confirms the possible association between carotid artery disorders and meningioma, involving for the first time a FFT. These findings make desirable to explore carotid district in patients with brain tumors, especially meningioma, even if symptoms suggestive of ischemic suffering are not present, in order to make an early diagnosis, so preventing marked ischemic events.

Last resort: case of clot translocation in intra-arterial stroke therapy.

A patient was taken for emergent intra-arterial stroke therapy for an acute left middle cerebral artery stroke syndrome, with CT angiography showing a left internal carotid artery (ICA) occlusion. Through a 6 F Neuron MAX sheath, a 5 Max ACE Penumbra aspiration catheter was advanced to the thrombus and direct suction was performed through the ACE catheter and Neuron MAX sheath. Upon pull back, the thrombus became wedged in the Neuron MAX sheath and despite several attempts to aspirate the thrombus, no clot could be obtained. The Neuron MAX sheath was withdrawn to the left common carotid artery, and gently advanced to the origin of the external carotid artery (ECA). A glide wire was advanced and the thrombus dislodged into the ECA. Another pass with the 5 Max ACE was used to remove a remaining thrombus in the left ICA terminus, resulting in Thrombolysis in Cerebral Infarction (TICI) 3 flow. With improved devices for embolectomy, large and rigid emboli that exceed the inner diameter of large guide sheaths and balloon guide catheters can become lodged, and cannot be withdrawn through a catheter. While uncommon, strategies to overcome this are important to keep in mind during acute stroke intervention.

Endovascular treatment of distal internal carotid artery occlusions with retrievable stents.

BACKGROUND: Acute stroke due to distal intracranial internal carotid artery (ICA) occlusion has a poor natural history. Outcome in patients who receive intravenous tissue plasminogen activator (tPA) is also unsatisfactory. The objective of this study is to evaluate the effectiveness and safety of endovascular treatment with retrievable stents in these patients. METHODS: Data from a prospective register of patients with acute stroke treated with an endovascular procedure in a single centre were analysed. RESULTS: A total of 20 patients with distal ICA occlusion were collected. Mean baseline National Institutes of Health Stroke Scale score was 18. Eight cases (40%) had received previous intravenous tPA. Mean time from stroke to recanalization was 393 min. Retrievable stents with proximal occlusion and aspiration were used in all cases. In 3 patients, 2 retrievable stents were used simultaneously. Complete recanalization (thrombolysis in cerebral infarction 2b/3) was accomplished in 85% of cases. A favourable clinical outcome (modified Rankin Scale score 0-2) was achieved in 13 patients (65%). Mortality occurred in 2 cases (10%). CONCLUSIONS: Endovascular treatment of patients with distal ICA occlusion seems safe and effective. Retrievable stents may be the treatment of choice, although randomized clinical trials are necessary. The use of 2 retrievable stents at the same time could be an alternative technique useful in thrombi of larger size.

Surgical embolectomy for large vessel occlusion of anterior circulation.

OBJECT: The aim of this study was to assess the technical details and the efficacy and safety of surgical embolectomy for occlusion of large vessels in the anterior circulation. METHODS: Twenty-three consecutive patients with acute ischemic stroke attributed to embolic occlusion of large arteries of the anterior circulation who underwent treatment with surgical embolectomy were retrospectively reviewed. Twenty patients were treated based on data from magnetic resonance angiography (MRA)-diffusion weighted imaging (DWI) mismatch, while three other patients had contraindications to magnetic resonance imaging (MRI) and were treated based on computed tomography (CT) and digital subtraction angiography (DSA) findings. Clinical outcomes, including recanalization rate, recanalization time, complications, modified Rankin Scale (mRS) at 3 months, and National Institute of Health Stroke Scale (NIHSS) score improvement at 1 month, were evaluated. RESULTS: Among the 23 patients (median age, 80 years; median presenting NIHSS score, 21 points), the occlusion site was the internal carotid artery (ICA) terminus in six patients, the M1 segment of the middle cerebral artery (MCA) in 10 patients, and the M2 division of the MCA in seven patients. Final recanalization status was thrombolysis in myocardial infarction (TIMI) 3 in 21 patients (91%). Median recanalization time from symptom onset and from start of surgery was 282 min and 70 min, respectively. One patient (4.3%) had symptomatic haemorrhage. Three patients (13%) had brain oedema due to massive infarction of affected vessel area; two of these patients had undergone embolectomy based on CT findings and had successful recanalization, while one patient underwent embolectomy based on MRI findings and did not have successful recanalization. All 18 patients who underwent embolectomy based on MRA-DWI mismatch and had successful recanalization did not develop additional confluent ischaemic lesion on postoperative DWI. At 3 months, seven patients (30%) had a mRS score of 0-2, eight patients (35%) had a mRS score of 3, and none of the patients had died. Sixteen patients (70%) demonstrated NIHSS score improvement of more than eight points at 1 month. CONCLUSION: Surgical embolectomy for occlusion of large vessels in the anterior circulation resulted in a high complete recanalization rate with an acceptable safety profile. Use of MRA-DWI mismatch as an indication for surgical embolectomy was associated with a reduced complication rate.

Unusual positional compression of the internal carotid artery causes carotid thrombosis and cerebral ischemia.

This article reports an unusual case of positional compression of internal carotid artery resulting in carotid thrombosis and stroke in a 37-year-old man. A patient was operated urgently for a free-floating thrombotic mass in the internal carotid artery. Open thrombectomy was performed in acute phase of stroke for prevention of the recapitulative cerebral thromboembolism. Hemiplegia completely disappeared within 7 months.

The war against error: a 15 year experience of completion angioscopy following carotid endarterectomy.

BACKGROUND: A policy of intra-operative transcranial Doppler (TCD) and completion angioscopy was previously associated with virtual abolition of intra-operative stroke (apparent upon recovery from anaesthesia) following carotid endarterectomy (CEA). The aims of this study were to determine whether the prevalence of technical error has diminished with experience and whether our monitoring/quality control policy was still associated with low rates of intra-operative stroke 20 years after its introduction. METHODS: Retrospective review of four consecutive cohorts of 400 patients undergoing CEA between October 1995 and March 2010 (1600 CEAS in total). RESULTS: One hundred four patients (7%) had thrombus removed following angioscopy and prior to flow restoration, while 31 (2.1%) underwent repair of a distal intimal flap. The prevalence of intimal flaps diminished from 4.9% in the first 400 patients to 0.8% in the last 400 patients (p = 0.006). By contrast, the prevalence of retained thrombus did not decline with experience (8.5%, 3.7%, 10.3% and 5.4% for the four consecutive periods). Intra-operative TCD and completion angioscopy was, however, associated with extremely low rates of intra-operative stroke (0.25%, 0.25%, 0.5% and 0.25% during the four study periods). CONCLUSION: Most intra-operative strokes probably follow embolisation of thrombus following restoration of flow. This can be prevented by angioscopy which has the advantage of being performed prior to flow restoration. Increasing experience was associated with a decline in the detection of intimal flaps, but not in the prevalence of retained thrombus. Even the most experienced of surgeons can still be responsible for inadvertent technical error.

Various endovascular approaches to the management of free floating carotid thrombi: a technical report.

Ischemic strokes are seldom caused by free floating thrombi (FFTs) in the carotid artery. Because FFTs are fairly uncommon and their pathophysiology has not yet been clarified, no definite management guidelines have been established. Four consecutive patients with FFTs in the internal and/or common carotid artery are described. These patients were successfully treated by various endovascular treatment methods.