[Cerebral arterial air embolism: the effect of hyperbaric oxygen therapy]. / Cerebrale arteriële luchtembolie.

BACKGROUND: Iatrogenic gas embolism is the presence of gas in vascular structures. Feared are those in coronary or cerebral arteries. These can result in cerebral or myocardial infarction. CASE DESCRIPTION: A 79-year-old female underwent CT-guided biopsy of the lung. Minutes later she developed neurological symptoms. After administration of oxygen her symptoms initially improved, but later worsened. Based on her symptoms air embolism was suspected. She recovered fully after treatment with hyperbaric oxygen. CONCLUSION: Air embolism is a potentially life-threatening complication of surgical, radiological or vascular interventions. Early recognition can lead to prompt treatment and better prognosis. If air embolism is suspected the patient should be treated according to ABCDE principles and oxygen should be administered. In case of neurological or circulatory symptoms a hospital that could provide hyperbaric oxygen therapy should be contacted as soon as possible.

Safety Evaluation of Primary Carotid Stenting: Transcranial Doppler and MRI.

BACKGROUND AND PURPOSE: Cerebral emboli are generated by every step of standard carotid angioplasty and stenting. Primary carotid stenting (PCS) is a technique in which the use of balloon angioplasty (BA) is minimized to decrease the embolic load. The primary aim of this study is to establish the number of emboli generated by each step of primary stenting and determine the relationship to new diffusion (DWI) lesions on subsequent magnetic resonance imaging (MRI). METHODS: Eighty-five patients with severe, symptomatic carotid stenosis were prospectively recruited and underwent carotid stenting. Intraoperative transcranial Doppler was performed in 77 patients. The number and size of microemboli for each of seven procedural steps were recorded. Correlation was made with the number and location of new DWI lesions. RESULTS: PCS was performed in 73 patients. BA was required in 12 patients. The mean number of microemboli was 114, and most microemboli were generated by stent deployment, followed by BA. Balloon techniques generated significantly more emboli than primary stenting (p = 0.017). There was a significant relationship between total microemboli and new DWI lesions (p = 0.009), and between new DWI lesions in multiple territories and the severity of pretreatment stenosis (p = 0.002). CONCLUSIONS: During PCS, more emboli are generated by stent deployment than during any other stage of the procedure. When BA is necessary, more malignant emboli are generated but total emboli are unchanged and there is no difference in new diffusion lesions on MRI. PCS is safe and is not inferior to historical controls for the generation of new DWI lesions.

A Single-Center Experience of Endovascular Treatment in Subtypes of Basilar Artery Occlusion: Embolization Caused by Tandem Vertebral Artery Stenosis May Be Associated with Better Outcomes.

OBJECTIVE: Basilar artery occlusion (BAO) is a severe condition with high mortality. However, surgical procedures and outcomes of BAO with different pathologic subtypes have not been fully clarified. This study compared the surgical procedures and clinical outcomes of mechanical thrombectomy in different subtypes of BAO. METHODS: Eighty-six patients with acute BAO receiving endovascular treatment between October 2015 and July 2019 were retrospectively analyzed and placed in 3 groups: pure embolism (group 1), arterial-arterial embolism from steno-occlusion of the tandem vertebral artery (group 2), and in situ atherosclerotic thrombosis (group 3). Recanalization rates, procedure times, surgical characteristics, and clinical outcomes were analyzed. RESULTS: Groups 1, 2, and 3 included 33 (38.4%), 17 (19.8%), and 36 (41.9%) patients, respectively. The overall successful recanalization rate was 95.3%, and the good outcome rate was 61.6%. The procedure time in group 1 was shorter than the time in groups 2 and 3 (P < 0.001). The clinical good outcome rate was higher in group 2 than in group 1 (88.2% vs. 54.5%; P = 0.017). Groups 1 and 3 had similar good outcome rates (54.5% vs. 55.6%; P = 0.933). Twenty-seven patients received stent angioplasty: 10 of 17 in group 2 (58.8%) and 17 of 36 in group 3 (47.2%). CONCLUSIONS: The outcome of endovascular treatment for BAO varies among patients with different pathologic mechanisms. Patients with embolism from tandem vertebral artery steno-occlusion achieved the best outcomes. Rescue treatment was more common in patients with embolic BAO with tandem vertebral artery steno-occlusion and BAO with in situ atherosclerotic thrombosis.

Recovery of Hypoxic Regions in a Rat Model of Microembolism.

OBJECTIVES: Endovascular treatment (EVT) has become the standard of care for acute ischemic stroke. Despite successful recanalization, a limited subset of patients benefits from the new treatment. Human MRI studies have shown that during removal of the thrombus, a shower of microclots is released from the initial thrombus, possibly causing new ischemic lesions. The aim of the current study is to quantify tissue damage following microembolism. MATERIALS AND METHODS: In a rat model, microembolism was generated by injection of a mixture of polystyrene fluorescent microspheres (15, 25 and 50 µm in diameter). The animals were killed at three time-points: day 1, 3 or 7. AMIRA and IMARIS software was used for 3D reconstruction of brain structure and damage, respectively. CONCLUSIONS: Microembolism induces ischemia, hypoxia and infarction. Infarcted areas persist, but hypoxic regions recover over time suggesting that repair processes in the brain rescue the regions at risk.

Post-traumatic cerebral fat embolism syndrome with a favourable outcome: a case report.

BACKGROUND: Fat embolism syndrome (FES) is a change in physiology resulting from mechanical causes, trauma, or sepsis. Neurological manifestations of FES can vary from mild cognitive changes to coma and even cerebral oedema and brain death. Here, we present an unusual case of cerebral fat emboli that occurred in the absence of acute chest syndrome or right-to-left shunt. CASE PRESENTATION: A previously healthy 57-year-old right-handed male was admitted to our department because of unconsciousness after a car accident for 3 days. He suffered from multiple fractures of the bilateral lower extremities and pelvis. This patient had severe anaemia and thrombocytopenia. Head MRI showed multiple small lesions in the whole brain consistent with a "star field" pattern, including high signals on T2-weighted (T2w) and fluid-attenuated inversion recovery (FLAIR) images in the bilateral centrum semiovale; both frontal, parietal and occipital lobes; and brainstem, cerebellar hemisphere, and deep and subcortical white matter. Intravenous methylprednisolone, heparin, mannitol, antibiotics and nutritional support were used. Although this patient had severe symptoms at first, the outcome was favourable. CONCLUSIONS: When patients have long bone and pelvic fractures, multiple bone fractures and deteriorated neurological status, cerebral fat embolism (CFE) should be considered. Additionally, CFE may occur without an intracardiac shunt. The early diagnosis and appropriate management of FES are important, and prior to and following surgery, patients should be monitored comprehensively in the intensive care unit. With appropriate treatment, CFE patients may achieve good results.

Two Cases of Cerebral Infarcts Caused by Topical Hemostatic Agent Embolism.

ABSTRACT: Resorbable topical hemostatic agents are widely used in surgical procedures to control intraoperative bleeding. There have been multiple reports of complications from use of these agents, including pulmonary vasculature thromboembolism, cerebral venous sinus occlusion, and postoperative inflammatory mass lesions each containing the hemostatic agent. We report 2 cases of inadvertent intra-arterial embolization of hemostatic agent. Both cases followed elective surgical cervical spinal procedures, during which gelatin-based local hemostatic agents were used to control unanticipated bleeding. Postoperatively, both patients exhibited neurologic defects and were found to have infarcts of the brain. At autopsy, vertebrobasilar thromboemboli containing foreign material grossly and microscopically consistent with hemostatic matrix material were found in both cases. These are the first reports of hemostatic agent embolization resulting in cerebral infarcts and leading to death.

Microembolus clearance through angiophagy is an auxiliary mechanism preserving tissue perfusion in the rat brain.

Considering its intolerance to ischemia, it is of critical importance for the brain to efficiently process microvascular occlusions and maintain tissue perfusion. In addition to collateral microvascular flow and enzymatic degradation of emboli, the endothelium has the potential to engulf microparticles and thereby recanalize the vessel, through a process called angiophagy. Here, we set out to study the dynamics of angiophagy in relation to cytoskeletal remodeling in vitro and reperfusion in vivo. We show that polystyrene microspheres and fibrin clots are actively taken up by (brain) endothelial cells in vitro, and chart the dynamics of the actin cytoskeleton during this process using live cell imaging. Whereas microspheres were taken up through the formation of a cup structure by the apical endothelial membrane, fibrin clots were completely engulfed by the cells, marked by dense F-actin accumulation surrounding the clot. Both microspheres and fibrin clots were retained in the endothelial cells. Notably, fibrin clots were not degraded intracellularly. Using an in vivo microembolization rat model, in which microparticles are injected into the common carotid artery, we found that microspheres are transported by the endothelium from the microvasculature into the brain parenchyma. Microembolization with microspheres caused temporal opening of the blood-brain barrier and vascular nonperfusion, followed by microsphere extravasation and restoration of vessel perfusion over time. Taken together, angiophagy is accompanied by active cytoskeletal remodeling of the endothelium, and is an effective mechanism to restore perfusion of the occluded microvasculature in vivo.

[The pathology of the thrombi obtained by endovascular thrombectomy were useful for diagnosis of two cases of cardiogenic cerebral embolism due to infective endocarditis and nonbacterial thrombotic endocarditis].

Patient 1 was a 55-year-old male with cerebral infarction due to obstruction of the left middle cerebral artery during treatment for bacteremia, along with a verruca of infectious endocarditis harvested from endovascular thrombectomy. Patient 2 was a 59-year-old female suffering from cerebral infarction at the terminal branch during intrahepatic cholangiocarcinoma chemotherapy who thereafter developed cerebral infarction again due to obstruction of the left middle cerebral artery, along with a verruca of nonbacterial thrombotic endocarditis (NBTE) harvested from endovascular thrombectomy. In tumor-bearing patients, while NBTE may be more closely related to the development of cerebral infarctions than previously assumed, we also need pay attention to the onset of infectious endocarditis. We need further studies on the effectiveness and safety of thrombolysis therapy and endovascular thrombectomy for cerebral infarctions due to endocarditis in both patients. The harvested emboli may provide clues to the differentiation thereof.

Standardized Fabrication Method of Human-Derived Emboli with Histologic and Mechanical Quantification for Stroke Research.

BACKGROUND: As access to patient emboli is limited, embolus analogs (EAs) have become critical to the research of large vessel occlusion (LVO) stroke and the development of thrombectomy technology. To date, techniques for fabricating standardized human blood-derived EAs are limited in the variety of compositions, and the mechanical properties relevant to thrombectomy are not quantified. METHODS: EAs were made by mixing human banked red blood cells (RBCs), plasma, and platelet concentrate in 10 different volumetric percentage combinations to mimic the broad range of patient emboli causing LVO strokes. The samples underwent histologic analysis and tensile testing to mimic the pulling action of thrombectomy devices, and were compared to patient emboli. RESULTS: EAs had histologic compositions of 0-96% RBCs, 0.78%-92% fibrin, and 2.1%-22% platelets, which can be correlated with the ingredients using a regression model. At fracture, EAs elongated from 81% to 136%, and the ultimate tensile stress ranged from 16 to 949 kPa. These EAs' histologic compositions and tensile properties showed great similarity to those of emboli retrieved from LVO stroke patients, indicating the validity of such EA fabrication methods. EAs with lower RBC and higher fibrin contents are more extensible and can withstand higher tensile stress. CONCLUSIONS: EAs fabricated and tested using the proposed new methods provide a platform for stroke research and pre-clinical development of thrombectomy devices.

Machine Learning Prediction of Stroke Mechanism in Embolic Strokes of Undetermined Source.

BACKGROUND AND PURPOSE: One-fifth of ischemic strokes are embolic strokes of undetermined source (ESUS). Their theoretical causes can be classified as cardioembolic versus noncardioembolic. This distinction has important implications, but the categories' proportions are unknown. METHODS: Using data from the Cornell Acute Stroke Academic Registry, we trained a machine-learning algorithm to distinguish cardioembolic versus non-cardioembolic strokes, then applied the algorithm to ESUS cases to determine the predicted proportion with an occult cardioembolic source. A panel of neurologists adjudicated stroke etiologies using standard criteria. We trained a machine learning classifier using data on demographics, comorbidities, vitals, laboratory results, and echocardiograms. An ensemble predictive method including L1 regularization, gradient-boosted decision tree ensemble (XGBoost), random forests, and multivariate adaptive splines was used. Random search and cross-validation were used to tune hyperparameters. Model performance was assessed using cross-validation among cases of known etiology. We applied the final algorithm to an independent set of ESUS cases to determine the predicted mechanism (cardioembolic or not). To assess our classifier's validity, we correlated the predicted probability of a cardioembolic source with the eventual post-ESUS diagnosis of atrial fibrillation. RESULTS: Among 1083 strokes with known etiologies, our classifier distinguished cardioembolic versus noncardioembolic cases with excellent accuracy (area under the curve, 0.85). Applied to 580 ESUS cases, the classifier predicted that 44% (95% credibility interval, 39%-49%) resulted from cardiac embolism. Individual ESUS patients' predicted likelihood of cardiac embolism was associated with eventual atrial fibrillation detection (OR per 10% increase, 1.27 [95% CI, 1.03-1.57]; c-statistic, 0.68 [95% CI, 0.58-0.78]). ESUS patients with high predicted probability of cardiac embolism were older and had more coronary and peripheral vascular disease, lower ejection fractions, larger left atria, lower blood pressures, and higher creatinine levels. CONCLUSIONS: A machine learning estimator that distinguished known cardioembolic versus noncardioembolic strokes indirectly estimated that 44% of ESUS cases were cardioembolic.

[Autopsy case of cerebral embolism with lung cancer and atrial fibrillation in which the left atrium may have become an incubator for a tumor embolus].

An 82-year-old man with advanced lung cancer who had declined aggressive therapy was transferred to our hospital due to sudden-onset consciousness disturbance, global aphasia, and right hemiplegia. An electrocardiogram showed atrial fibrillation, and brain MRI and MRA revealed acute ischemic lesions of the left hemisphere and occlusion of the left internal carotid artery (ICA), respectively. We diagnosed acute ischemic stroke due to left ICA occlusion and performed endovascular thrombectomy, which resulted in complete recanalization of the left ICA after retrieval of the culprit embolus. Pathological examination of the retrieved thrombus revealed the presence of tumor tissue, as well as fibrin or red blood cells. Treatment was continued after admission, but the patient died of respiratory failure on day 40 of hospitalization. Autopsy revealed invasion of the tumor in the pulmonary vein, but not in the wall of the left atrium where thrombi were present. However, pathological examination of these thrombi in the left atrium revealed tumor tissue, along with fibrin or red blood cells. These findings suggest that the wall of the left atrium, in which lung cancer had not invaded, may be an incubator of a mixed embolus containing tumor tissue and thrombi in a case of cerebral embolism associated with both lung cancer and atrial fibrillation.

An Unusual Case (Metastatic-Like Lesion) of Septic Cerebral Embolus Caused by Corynebacterium mucifaciens in a Diabetic Patient.

Septic cerebral emboli can be a challenging diagnosis to give, especially if atypical bacterial infections are the cause of it. Correct diagnosis of this condition can change the management route of the patient and result in a nonsurgical treatment. To our best knowledge, this is the first case of septic cerebral embolus caused by Corynebacterium mucifaciens reported. In this study, a 65-year-old diabetic patient who have developed ketoacidosis and went into coma was investigated for a case of septic cerebral embolization. The patient developed a sudden right-sided hemiparesis, and the radiological findings showed a tumor-like lesion on the left hemisphere at the level of the internal capsule. At first glance, presence of a metastatic tumor could not be excluded; therefore, further laboratory tests and examinations were done to rule out metastatic lesions. The blood culture of the patient revealed a case of bacteremia caused by Corynebacterium mucifaciens and then a septic cerebral embolus was suspected, but due to the rarity of this pathogen causing such complications as well as the similarity of the lesion to a metastatic brain tumor, a biopsy was performed and the histopathological findings confirmed the diagnosis of a septic cerebral embolus. Corynebacterium mucifaciens should be considered a human pathogen in immunocompromised patients and it can cause cerebral septic embolization. Metastatic brain tumors and tuberculomas should be excluded; if the uncertainty of a metastatic tumor remains, biopsy can be performed and histological findings can amplify the diagnosis of septic cerebral embolus.

Posterior cerebral artery stroke by reverse flow embolism in thoracic outlet syndrome - a case report.

BACKGROUND: Arterial thoracic outlet syndrome is a rare condition characterized by a subclavian artery pathology associated with a bone abnormality. It is rarely associated with thromboembolic stroke. The mechanism of cerebral embolism associated with thoracic outlet syndrome have rarely been demonstrated. We present here a fully studied case with a high probability of reverse flow embolism. CASE PRESENTATION: A 24-year-old man with a known arterial thoracic outlet syndrome presented with a right cerebral posterior artery brain infarction. An ultrasound examination depicted the compression of the right subclavian artery in the scalene defile with a post stenotic aneurysm and the presence of a floating thrombus in this aneurysm. There was a reverse flow during diastole in this aneurysm. Anticoagulation was carried out with the disappearance of the floating thrombus with no new clinical or brain MRI event. Corrective surgery of this thoracic outlet syndrome was performed one month after stroke. CONCLUSION: Very few cases of stroke in arterial thoracic outlet syndrome have been described with thorough dynamic vascular imaging. To our knowledge, this is the fourth reported case that advocates for a reverse flow embolism mechanism in stroke associated with thoracic outlet syndrome, and the first to realize an extensive ultrasound and doppler workup.

Unusual clinicopathological presentation of nontraumatic cerebral fat embolism: Two-case report.

RATIONALE: Fat embolism syndrome (FES) is characterized by the classical triad of cerebral, respiratory, and cutaneous manifestations. In contrast, cerebral fat embolism (CFE), corresponding to incomplete pure type FES, is much rarer and usually follows trauma. CFE typically shows a "starfield" pattern on diffusion-weighted magnetic resonance imaging due to the involvement of multiple small arteries. We report 2 unusual cases of CFE that showed a nontraumatic etiology and the involvement of a single dominant cerebral artery. PATIENT CONCERNS: Case 1 was a 33-year-old woman without a history of trauma who visited the emergency room due to hemiparesis and hemisensory deficits. She was a heavy smoker and had used oral contraceptives for several years. Most importantly, she had 2 experiences of autologous fat grafting 2 months previously. Magnetic resonance angiography (MRA) revealed acute occlusion of the right middle cerebral artery. Case 2 was an 80-year-old man suddenly presented with dizziness, ataxia, and left-sided sensorimotor dysfunction. He had a history of hypertension, untreated atrial fibrillation, and chronic alcoholism. MRA demonstrated the occlusion of the distal basilar artery. DIAGNOSIS: Case 1: Microscopic findings demonstrated variable sized fat vacuoles intermixed with moderate amounts of thrombi. Case 2: Histologically, mature adipocytes were intermingled with fibrin, blood cells, and a fragment of entrapped soft tissue resembling the vessel wall. INTERVENTION: Case 1 and 2 underwent aspirational thrombectomy guided by transfemoral cerebral angiography. OUTCOME: Case 1 recovered well but Case 2 still suffers from gait ataxia. LESSONS: CFE can rarely occur in various nontraumatic conditions, with or without evident etiology. Furthermore, it may not show characteristic clinicopathological manifestations. Therefore, careful follow up of those who have undergone procedures that are likely to trigger FES or who have hemodynamic or hypercoagulable risk factors is needed.

Is Histologic Thrombus Composition in Acute Stroke Linked to Stroke Etiology or to Interventional Parameters?

BACKGROUND AND PURPOSE: Detailed insight into the composition of thrombi retrieved from patients with ischemic stroke by mechanical thrombectomy might improve pathophysiologic understanding and therapy. Thus, this study searched for links between histologic thrombus composition and stroke subtypes and mechanical thrombectomy results. MATERIALS AND METHODS: Thrombi from 85 patients who had undergone mechanical thrombectomy for acute ischemic stroke between December 2016 and March 2018 were studied retrospectively. Thrombi were examined histologically. Preinterventional imaging features, stroke subtypes, and interventional parameters were re-analyzed. Statistical analysis was performed with the Kruskal-Wallis test, Mann-Whitney U test, or Spearman correlation as appropriate. RESULTS: Cardioembolic thrombi had a higher percentage of macrophages and a tendency toward more platelets than thrombi of large-artery atherosclerotic stenosis (P = .021 and .003) or the embolic stroke of undetermined source (P = .037 and .099) subtype. Thrombi prone to fragmentation required the combined use of contact aspiration and stent retrieval (P = .021) and were associated with an increased number of retrieving maneuvers (P = .001), longer procedural times (P = .001), and a higher lymphocyte content (P = .035). CONCLUSIONS: We interpreted the higher macrophage and platelet content in cardioembolic thrombi compared with large-artery atherosclerotic stenosis or embolic stroke of undetermined source thrombi as an indication that the latter type might be derived from an atherosclerotic plaque rather than from an undetermined cardiac source. The extent of thrombus fragmentation was associated with a more challenging mechanical thrombectomy and a higher lymphocyte content of the thrombi. Thus, thrombus fragmentation not only might be caused by the recanalization procedure but also might be a feature of a lymphocyte-rich, difficult-to-retrieve subgroup of thrombi.

Intracranial Aneurysms After Intravenous Thrombolysis in Patient with Atrial Myxoma: A Case Study.

We administered intravenous thrombolytic therapy to a 51-year-old female patient with a 101-min stroke onset. The patient was unconscious during the manifestation of symptoms. Computed tomography angiography examination of the intracranial artery at the time of admission suggested that the left middle cerebral artery was occluded. The patient regained consciousness after the intravenous thrombolytic treatment was administered. On an urgent cerebral angiography, it was revealed that the recanalization of the left middle cerebral artery was successful. Although blood perfusion was restored, occlusion of the distal blood flow remained. The symptoms of the patient gradually improved after the treatment. However, 6 months after the onset of the condition, intracranial aneurysms formed distal to the recanalized arteries that were previously embolized. The full process underlying the development of cerebral embolism caused by atrial myxomas and subsequent formation of aneurysms is illustrated in this patient. Although the underlying mechanism remains unclear, intravenous thrombolysis can successfully restore cerebral blood flow in and may improve the prognosis of patients with cerebral embolism caused by cardiac myxoma. Despite the positive revascularization therapy, the occurrence of the complication of intracranial aneurysms is possible. Long-term follow-up to evaluate the progression of myxomatous aneurysms after cerebral embolism with conservative treatment may be a suitable strategy for managing such patients.

[Cerebral embolism as an atypical presentation of May Thurner syndrome]. / Embolia cerebral como presentación atípica de síndrome de May Thurner.

May-Thurner syndrome is an anatomic abnormality that predisposes patients to increase risk of paradoxical embolism and stroke. It consists of chronic compression of the left common iliac vein by the overlying right common iliac artery and lumbar spine. This may lead to deep venous thrombosis and paradoxical embolism that could provoke cerebral ischemia in patients with a cardiac shunt from right-to-left. Embolic cerebral ischemic event is reported in a 30-year-old man after sexual intercourse. Further studies revea led suggestive findings of May-Thurner syndrome coupled with a patent foramen ovale and a factor V Leiden thrombophilia. He was placed on anticoagulation therapy and has not had any recurrent events.

El síndrome de May-Thurner es una anormalidad anatómica que consiste en la comprensión cronica de la vena iliaca común izquierda, entre la arteria ilíaca común derecha y la columna vertebral, que puede predisponer a la trombosis venosa profunda. Es una entidad rara, y es infrecuente que provoque una embolia paradojal cerebral. Se presenta el caso de una isquemia cerebral de origen embólico, en un varón de 30 años, luego de actividad sexual. Los estudios realizados revelaron síndrome de May-Thurner asociado con un foramen oval permeable y una trombofilia por factor V de Leiden. Fue tratado con anticoagulantes orales y no ha presentado recurrencias.

Embolia cerebral como presentación atípica de síndrome de May Thurner

El síndrome de May-Thurner es una anormalidad anatómica que consiste en la comprensión cronica de la vena iliaca común izquierda, entre la arteria ilíaca común derecha y la columna vertebral, que puede predisponer a la trombosis venosa profunda. Es una entidad rara, y es infrecuente que provoque una embolia paradojal cerebral. Se presenta el caso de una isquemia cerebral de origen embólico, en un varón de 30 años, luego de actividad sexual. Los estudios realizados revelaron síndrome de May-Thurner asociado con un foramen oval permeable y una trombofilia por factor V de Leiden. Fue tratado con anticoagulantes orales y no ha presentado recurrencias.

May-Thurner syndrome is an anatomic abnormality that predisposes patients to increase risk of paradoxical embolism and stroke. It consists of chronic compression of the left common iliac vein by the overlying right common iliac artery and lumbar spine. This may lead to deep venous thrombosis and paradoxical embolism that could provoke cerebral ischemia in patients with a cardiac shunt from right-to-left. Embolic cerebral ischemic event is reported in a 30-year-old man after sexual intercourse. Further studies revea led suggestive findings of May-Thurner syndrome coupled with a patent foramen ovale and a factor V Leiden thrombophilia. He was placed on anticoagulation therapy and has not had any recurrent events.

Impaired Arterial Elastic Properties and Endothelial Glycocalyx in Patients with Embolic Stroke of Undetermined Source.

BACKGROUND AND PURPOSE: Cardioembolism is a postulated mechanism of embolic stroke of undetermined source (ESUS). We investigated endothelial glycocalyx, aortic elastic properties, oxidative stress, and their association with left atrial (LA) function in ESUS and healthy individuals. METHODS: In 90 ESUS patients (age 50.4 ± 13.2) and 90 controls with similar risk factors, we measured: (1) perfused boundary region (PBR) of the sublingual arterial microvessels (range 5-25 µm), a marker inversely related with glycocalyx thickness, (2) pulse wave velocity (PWV), central systolic blood pressure (cSBP), and augmentation index (AIx), (3) LA volume and strain using speckle-tracking imaging, and (4) malondialdehyde (MDA) and protein carbonyls (PCs), as oxidative stress markers. RESULTS: Compared with controls, ESUS had higher PWV, PBR, MDA, and PC levels as well as higher LA volume and reduced reservoir LA strain (p < 0.05). PBR > 1.2 µm of microvessel ranging from 5 to 9 µm and PWV > 10.2 m/s were associated with ESUS on multivariable analysis (odds ratio: 2.374 and 5.429, p < 0.05, respectively) and increased the c-statistic of the initial model from 0.54 to 0.71. In ESUS, glycocalyx damage (increased PBR) was related with increased PWV (p < 0.01) which was linked with LA reservoir strain after controlling for age, sex, and risk factors (p = 0.03). Increased MDA and PC were related with glycocalyx damage, increased PWV (r = 0.67 and r = 0.52), AIx, cSBP, and aortic atheroma (p < 0.01). CONCLUSION: Arterial function and endothelial glycocalyx are severely impaired in ESUS and are linked to LA dysfunction suggesting their contribution to ESUS pathogenesis. CLINICAL TRIAL REGISTRATION: URL-http://www.clinicaltrials.gov. Unique identifier: NCT03609437.