Fibrin-Platelet Clots in Acute Ischemic Stroke. Predictors and Clinical Significance in a Mechanical Thrombectomy Series.

Introduction: The histological composition of the clot influences its mechanical properties, affects the efficacy of endovascular treatment (EVT), and could determine the clinical outcome of patients with acute ischemic stroke (AIS). Insights into clot composition may guide therapeutic decision-making prior to EVT and facilitate revascularization therapies. Material and Methods: Consecutive patients with AIS recorded in a prospective single-center reperfusion registry from December 2015 to December 2019 and treated with EVT were included. Baseline, laboratory [including post-procedural C-reactive protein (CRP)], radiological, and angiographic variables were analyzed. We aimed to study the relationship between histological composition of the clot with basal neuroimaging, laboratory markers, and recanalization technique. The secondary outcome was to analyze the correlation between clot composition and functional outcome at 3 months assessed by the modified Rankin scale (mRS). Results: From the study period, 360 AIS patients treated with EVT were included, of whom 189 (53%) fulfilled the inclusion criteria. One hundred (53%) cases of fibrin-predominant clot (FPC) were recorded. Full recanalization in FPC cases was achieved with higher probability when stent retrievers (SR) were selected as the first-line device (68.2%, p = 0.039). Patients with FPC had higher levels of CRP (p = 0.02), lower frequency of the hyperdense middle cerebral artery (HMCA) in baseline imaging (p = 0.039), and higher rates of mortality (p = 0.012). The multivariate analysis showed that the absence of HMCA (OR = 0.420; 95% CI 0.197-0.898; p = 0.025) and higher levels of CRP (OR = 1.01; 95% CI 1.003-1.019; p = 0.008) were predictors of FPC. Leukocytes and platelet counts were not associated with clot histology. Conclusions: The absence of HMCA and higher levels of CRP were markers of FPC. In patients with FPC, complete recanalization was most likely to be achieved when a SR was selected as first line of treatment. Mortality was higher in patients within this histologic group.

Subarachnoid hemorrhage due to intradural cerebral aneurysm and simultaneous spinal subdural hematoma: illustrative case.

BACKGROUND: Spontaneous spinal subdural hematomas (SSDHs) are unusual. Among their probable etiologies, an association with ruptured brain aneurysms has been described in an extraordinary way. The underlying pathophysiological mechanism is not conclusively described in the literature. OBSERVATIONS: The authors reported an exceptional case of a 59-year-old woman admitted for a condition that included sudden headache, stiff neck, and vomiting associated with pain in the left flank area that radiated to the leg. Computed tomography (CT) of the brain evidenced acute subarachnoid hemorrhage distributed in the bilateral posterior parieto-occipital fossa and occipital horns of the ventricles. CT angiography detected a dissecting aneurysm in the left vertebral artery (V4) that was treated urgently via the endovascular route. In the next hours, the patient's symptoms worsened, with paraplegia of the lower extremities. Magnetic resonance imaging showed SSDH at T4-6 and extensive associated myelopathy. LESSONS: The origin of the spinal hematoma may be the rupture of the aneurysm of the V4 segment in the dura mater of the foramen magnum and subsequent rostrocaudal migration of the hemorrhage to the spinal subdural space, enhanced by an intracranial pressure increase. This hypothesis is discussed, as is a brief literature review.

Comaneci device-assisted embolization of wide-necked carotid aneurysms with an unfavorable ratio.

BACKGROUND: Endovascular treatment is the technique of choice for most intracranial aneurysms. However, the treatment of morphologically complex wide-necked aneurysms with an unfavorable anatomy is still a therapeutic challenge. The purpose of the study is to describe the initial experience with the Comaneci embolization assist device for the treatment of wide-necked aneurysms with an unfavorable ratio for direct embolization. METHODS: We report a retrospective single-center analysis taken from a prospective database of consecutive aneurysms of the anterior circulation treated using the Comaneci device in the period from March 2017 to March 2019. RESULTS: Eighteen aneurysms were collected from 16 patients (9 women and 7 men) treated using the Comaneci device. The mean age was 48.4 years (range 36-81). Twelve patients had SAH, three were incidental aneurysms and one had compressive symptoms. A complete asymptomatic occlusion rate of 88.8% was obtained. The major complication rate was 5.55%. CONCLUSION: The Comaneci embolization assist device is a safe, effective option for endovascular treatment of complex aneurysms with an unfavorable ratio.

Endovascular management of an unsual case of spontaneous Retroperitoneal Haemorrhage due to Fibromuscular Dysplasia.

BACKGROUND: Fibromuscular dysplasia (FMD) is an uncommon vascular disease that results in stenosis, dissection or aneurysmal degeneration. However, it can sometimes manifest atypically, as we show in this case. CASE PRESENTATION: A 24-year old patient with no relevant medical history with severe left hypochondrium pain. The physical examination showed blood pressure levels of 160/90 mmHg. An abdominopelvic CT evidenced left retroperitoneal haematoma associated with active bleeding and left renal artery stenosis. Given these findings, it was decided to perform an endovascular treatment. Significant stenosis was seen during the arteriography in both renal arteries, suggesting fibromuscular dysplasia and development of a collateral neovascular network responsible for the retroperitoneal haematoma. It was embolised in association with angioplasty of the left renal artery. The patient had a favourable outcome; however, high blood pressure levels persisted. A new bilateral renal angioplasty was performed, which returned blood pressure values to normal. The patient was discharged without needing antihypertensives. CONCLUSIONS: FMD is a rare disease that can show multiple clinical presentations and need individualized treatment options. Endovascular techniques are in the first therapeutic line regarding fibromuscular dysplasia.

Simultaneous Angioplasty and Mechanical Thrombectomy in Tandem Carotid Occlusions. Incidence of Reocclusions and Prognostic Predictors.

OBJECTIVES: The best revascularization technique for tandem carotid occlusions is not clearly defined. The primary objective of this study is to describe our technical and clinical results, analyzing the main predictors of functional independence. The secondary objective is the analysis of stent reocclusion rate. METHODS: A single-center series of 250 mechanical thrombectomies in the anterior circulation was studied. A subsequent analysis of 40 carotid occlusions was performed. The demographics, etiology, angiographic results, antithrombotic drugs, and 3-month follow-up were registered. A bivariate analysis was performed to establish the association of the study variables with major clinical complications (death, symptomatic hemorrhagic transformation and early recurrence) and the functional prognosis. In addition, the relationship between the preprocedure antiaggregation regimen and the reocclusions was studied, as well as its clinical impact. Independent predictive factors were studied using a multivariate logistic regression model. RESULTS: Complete recanalization was achieved in 30 cases (75%). Simultaneous stent placement was decided in 32 cases (80%). Functional independence was reached in 19 cases (47.5%), and 3 (7.5%) died at 3 months. Seven major complications were reported (17.5%). In patients with satisfactory revascularization where a carotid stent was used, 9 reocclusions (28.1%) were detected during the follow-up, 2 of them symptomatic. The only factor related independently with functional independence was the administration of single antiaggregation (odds ratio = .31; 95% confidence interval .002-.595; P = .021). CONCLUSIONS: Urgent endovascular treatment of tandem carotid occlusions has shown to be effective and safe in our series. The administration of single antiaggregation is a predictor of functional independence. In patients treated with carotid stent, the reocclusion rate is high, but generally asymptomatic.

Histopathological and Bacteriological Analysis of Thrombus Material Extracted During Mechanical Thrombectomy in Acute Stroke Patients.

PURPOSE: Management of stroke secondary to septic emboli (SE) remains challenging, due to both the lack of specific recommendations and the gravity of the underlying pathology.The aim of this study is to describe the presence of SE in a series of mechanical thrombectomies (MT), analyzing technical complexity and outcomes with respect to the patients by means of histological analysis and microbiological study of the clot. METHODS: All the retrieved clots were studied under an established protocol, including histopathological and bacteriological study with hematoxylin-eosin, Gram and Gomori trichrome staining.Technical complexity in SE with respect to the series was evaluated by analyzing time of the procedures, number of passes and use of intracranial definitive stents. RESULTS: Over a 24-month period, bacteria were detected in the retrieved clot of four out of 65 patients (incidence 6.2%). Two cases were eventually diagnosed with infective endocarditis, while the remaining two were diagnosed with urinary tract infection and respiratory septicemia, respectively. Three of the four patients (75%) required an intracranial definitive stent in order to achieve successful recanalization.These procedures were significantly longer (137.7 vs. 59.8 min, p < 0.001), needed a higher number of passes (5.8 vs. 2.2, p < 0.001), and delivery of an intracranial stent more frequently (75% vs. 1.6%, p = 0.008), with respect to the rest of the series. CONCLUSIONS: In our series, systematic histopathological and bacteriological study of the MT samples allowed a higher proportion of SE diagnosis in comparison with previous reports.