Vasa vasorum interna in the carotid wall of active forms of Takayasu arteritis evidenced by ultrasound localization microscopy.

Introduction: Takayasu arteritis (TA) is associated with microvascularization of the wall of large arteries and is related to inflammation. Ultrasound localization microscopy (ULM), combining ultrafast ultrasound imaging with microbubble (MB) injection, can track the path of MBs within the arterial wall and thus provide imaging of the vasa vasorum. From the analysis of MB tracks in the common carotid arteries of patients with active TA, we report the presence of microvessels in connection with the carotid lumen (i.e., vasa vasorum interna [VVI]). Methods: ULM maps were obtained on five patients with active disease in the observational single-center series of the TAK-UF study. MB tracks connected to the carotid lumen were automatically identified, allowing the reconstruction of VVI. Results: MB tracking allows us to observe a microvascular network on the inner part of the wall, with some vessels in communication with the carotid lumen. This type of vessel was identified in all patients with active TA (n = 5) with a median of 2.2 [1.1-3.0] vessels per acquisition (2D longitudinal view of 3 cm of the common carotid artery). The blood flow within these vessels is mainly centrifugal; that is, toward the adventitia (88% [54-100] of MB tracks with flow directed to the outer part of the wall). Conclusion: VVI are present in humans in the case of active TA and emphasize the involvement of the intima in the pathological process. ClinicalTrials.gov Identifier: NCT03956394.

Occurrence of Major Local Lower Limb Events in Type 2 Diabetic Patients with Lower Extremity Arterial Disease: Impact of Metformin.

BACKGROUNDS: Patients with type 2 diabetes mellitus (T2DM) are particularly at risk of developing major adverse cardiovascular events (MACE) and peripheral artery disease (PAD) due to an acceleration of the atherosclerotic process linked to hyperglycemia and inflammation with a greater risk of local complications. We aimed to identify the predictive factors for major adverse limb events (MALE) in T2DM patients with PAD to manage modifiable factors at an early stage. METHODS: This is a prospective study in which T2DM patients with PAD were included from November 2017 to May 2018 and followed over 12 months. The predictive factors for the onset of MALE, MACE, and death from all causes have been identified. RESULTS: A total of 100 patients were included; 37% of the patients developed a MALE. After multivariate analysis, metformin was associated with a decrease of MALE (odds ratio (OR) = 0.26; 95% confidence interval (CI) [0.10; 0.68]; P = 0.007), and a history of the treatment of intravenous iloprost was associated with an increased risk of MALE (OR = 5.70; 95% CI [1.31; 31.93]; P = 0.029). Regular physical activity was associated with a decreased risk of MACE (OR = 0.07; 95% CI [0; 0.44]; P = 0.021). A history of stroke and a history of venous thromboembolism were associated with an increased all-cause mortality risk with OR = 3.68; 95% CI [1.17; 11.5]; P = 0.025 and OR = 3.78; 95% CI [1.16; 12.3]; P = 0.027. CONCLUSIONS: Metformin is protective against local complications in people with diabetes with PAD and should be prescribed to diabetic patients with PAD at an early stage.

Prior participation as a standardized patient improves OSCE scores of third-year medical students: A pilot comparative study at Université Paris Cité Medical School.

OBJECTIVE: Objective structured clinical examinations (OSCE) are one of the main modalities of skills' assessment of medical students. We aimed to evaluate the educational value of the participation of third-year medical students in OSCE as standardized patients. METHODS: We conducted a pilot OSCE session where third-year students participated in sixth-year students' OSCE as standardized patients (cases). Their scores in their own subsequent OSCE exams were compared with third-year students who had not participated (controls). Students' perceptions (stress, preparedness, ease) regarding their OSCE were compared with self-administered questionnaires. RESULTS: A total of 42 students were included (9 cases and 33 controls). Median [IQR] overall score (out of 20 points) obtained by the cases was 17 [16.3-18] versus 14.5 [12.7-16.3] for controls (p < 0.001). Students' perception of their evaluation (difficulty, stress, communication) was not significantly different between cases and controls. Most cases agreed that their participation was beneficial in reducing their stress (67%), increasing their preparedness (78%) and improving their communication skills (100%). All cases agreed that this participation should be offered more widely. CONCLUSION: Students' participation in OSCE as standardized patients led to better performance on their own OSCE and were considered beneficial. This approach could be more broadly generalized to improve student performance.

Inherited Thrombophilia in the Era of Direct Oral Anticoagulants.

Severe inherited thrombophilia includes rare deficiencies of natural anticoagulants (antithrombin and proteins C and S) and homozygous or combined factor V Leiden and FII G20210A variants. They are associated with a high thrombosis risk and can impact the duration of anticoagulation therapy for patients with a venous thromboembolism (VTE) event. Therefore, it is important to diagnose thrombophilia and to use adapted anticoagulant therapy. The widespread use of direct anticoagulants (DOACs) for VTE has raised new issues concerning inherited thrombophilia. Concerning inherited thrombophilia diagnosis, DOACs are directed toward either FIIa or FXa and can therefore interfere with coagulation assays. This paper reports DOAC interference in several thrombophilia tests, including the assessment of antithrombin, protein S, and protein C activities. Antithrombin activity and clot-based assays used for proteins C and S can be overestimated, with a risk of missing a deficiency. The use of a device to remove DOACs should be considered to minimize the risk of false-negative results. The place of DOACs in the treatment of VTE in thrombophilia patients is also discussed. Available data are encouraging, but given the variability in thrombosis risk within natural anticoagulant deficiencies, evidence in patients with well-characterized thrombophilia would be useful.

Circulating Von Willebrand factor and high molecular weight multimers as markers of endothelial injury predict COVID-19 in-hospital mortality.

BACKGROUND: Coronavirus disease 2019 (COVID-19) is a respiratory disease associated with endotheliitis and microthrombosis. OBJECTIVES: To correlate endothelial dysfunction to in-hospital mortality in a bi-centric cohort of COVID-19 adult patients. METHODS: Consecutive ambulatory and hospitalized patients with laboratory-confirmed COVID-19 were enrolled. A panel of endothelial biomarkers and von Willebrand factor (VWF) multimers were measured in each patient ≤ 48 h following admission. RESULTS: Study enrolled 208 COVID-19 patients of whom 23 were mild outpatients and 189 patients hospitalized after admission. Most of endothelial biomarkers tested were found increased in the 89 critical patients transferred to intensive care unit. However, only von Willebrand factor antigen (VWF:Ag) scaled according to clinical severity, with levels significantly higher in critical patients (median 507%, IQR 428-596) compared to non-critical patients (288%, 230-350, p < 0.0001) or COVID-19 outpatients (144%, 133-198, p = 0.007). Moreover, VWF high molecular weight multimers (HMWM) were significantly higher in critical patients (median ratio 1.18, IQR 0.86-1.09) compared to non-critical patients (0.96, 1.04-1.39, p < 0.001). Among all endothelial biomarkers measured, ROC curve analysis identified a VWF:Ag cut-off of 423% as the best predictor for in-hospital mortality. The accuracy of VWF:Ag was further confirmed in a Kaplan-Meier estimator analysis and a Cox proportional Hazard model adjusted on age, BMI, C-reactive protein and D-dimer levels. CONCLUSION: VWF:Ag is a relevant predictive factor for in-hospital mortality in COVID-19 patients. More than a biomarker, we hypothesize that VWF, including excess of HMWM forms, drives microthrombosis in COVID-19.

Wall Shear Stress Measurement by Ultrafast Vector Flow Imaging for Atherosclerotic Carotid Stenosis.

OBJECTIVE: Carotid plaque vulnerability assessment could guide the decision to perform endarterectomy. Ultrafast ultrasound imaging (UF) can evaluate local flow velocities over an entire 2D image, allowing measurement of the wall shear stress (WSS). We aimed at evaluating the feasibility of WSS measurement in a prospective series of patients with carotid stenosis. METHODS: UF acquisitions, performed with a linear probe, had an effective frame rate of 5000 Hz. The flow velocity was imaged over the entire plaque area. WSS was computed with the vector field speed using the formula: with the blood velocity and µ, the blood viscosity. The WSS measurement method was validated using a calibrated phantom. In vivo, WSS was analyzed in 5 areas of the carotid wall: common carotid artery, plaque ascent, plaque peak, plaque descent, internal carotid artery. RESULTS: Good correlation was found between in vitro measurement and the theoretical WSS values (R2 = 0.95; p < 0.001). 33 patients were prospectively evaluated, with a median carotid stenosis degree of 80 % [75-85]. The maximum WSS value over the cardiac cycle follows the shape of the plaque with an increase during the ascent, reaching its maximum value of 3.25 Pa [2.26-4.38] at the peak of the plaque, and a decrease after passing of the peak (0.93 Pa [0.80-1.19]) lower than the WSS values in the non-stenotic areas (1.47 Pa [1.12-1.77] for the common carotid artery). CONCLUSION: UF allowed local and direct evaluation of the plaque's WSS, thus better characterizing local hemodynamics to identify areas of vulnerability. KEY POINTS: · Ultrafast vector Doppler allows calculation of the wall shear stress (WSS) by measuring velocity vectors over the entire 2D image.. · The setup to measure the WSS has been validated in vitro on a linear flow phantom by comparing measurements to in silico calculations.. · Applying this method to carotid plaque allows us to better describe the hemodynamic constraints that apply along the entire length of the plaque..

Angiopoietin-2 as a marker of endothelial activation is a good predictor factor for intensive care unit admission of COVID-19 patients.

BACKGROUND: Coronavirus disease-2019 (COVID-19), a respiratory disease has been associated with ischemic complications, coagulation disorders, and an endotheliitis. OBJECTIVES: To explore endothelial damage and activation-related biomarkers in COVID-19 patients with criteria of hospitalization for referral to intensive care unit (ICU) and/or respiratory worsening. METHODS: Analysis of endothelial and angiogenic soluble markers in plasma from patients at admission. RESULTS: Study enrolled 40 consecutive COVID-19 patients admitted to emergency department that fulfilled criteria for hospitalization. Half of them were admitted in conventional wards without any ICU transfer during hospitalization; whereas the 20 others were directly transferred to ICU. Patients transferred in ICU were more likely to have lymphopenia, decreased SpO2 and increased D-dimer, CRP and creatinine levels. In those patients, soluble E-selectin and angiopoietin-2 were significantly increased (p value at 0.009 and 0.003, respectively). Increase in SELE gene expression (gene coding for E-selectin protein) was confirmed in an independent cohort of 32 patients using a whole blood gene expression profile analysis. In plasma, we found a strong association between angiopoetin-2 and CRP, creatinine and D-dimers (with p value at 0.001, 0.001 and 0.003, respectively). ROC curve analysis identified an Angiopoietin-2 cut-off of 5000 pg/mL as the best predictor for ICU outcome (Se = 80.1%, Sp = 70%, PPV = 72.7%, NPV = 77%), further confirmed in multivariate analysis after adjustment for creatinine, CRP or D-dimers. CONCLUSION: Angiopoietin-2 is a relevant predictive factor for ICU direct admission in COVID-19 patients. This result showing an endothelial activation reinforces the hypothesis of a COVID-19-associated microvascular dysfunction.

Management of carotid stenosis for primary and secondary prevention of stroke: state-of-the-art 2020: a critical review.

Carotid atherosclerotic plaque is encountered frequently in patients at high cardiovascular risk, especially in the elderly. When plaque reaches 50% of carotid lumen, it induces haemodynamically significant carotid stenosis, for which management is currently at a turning point. Improved control of blood pressure, smoking ban campaigns, and the widespread use of statins have reduced the risk of cerebral infarction to <1% per year. However, about 15% of strokes are still secondary to a carotid stenosis, which can potentially be detected by effective imaging techniques. For symptomatic carotid stenosis, current ESC guidelines put a threshold of 70% for formal indication for revascularization. A revascularization should be discussed for symptomatic stenosis over 50% and for asymptomatic carotid stenosis over 60%. This evaluation should be performed by ultrasound as a first-line examination. As a complement, computed tomography angiography (CTA) and/or magnetic resonance angiography are recommended for evaluating the extent and severity of extracranial carotid stenosis. In perspective, new high-risk markers are currently being developed using markers of plaque neovascularization, plaque inflammation, or plaque tissue stiffness. Medical management of patient with carotid stenosis is always warranted and applied to any patient with atheromatous lesions. Best medical therapy is based on cardiovascular risk factors correction, including lifestyle intervention and a pharmacological treatment. It is based on the tri-therapy strategy with antiplatelet, statins, and ACE inhibitors. The indications for carotid endarterectomy (CEA) and carotid artery stenting (CAS) are similar: for symptomatic patients (recent stroke or transient ischaemic attack ) if stenosis >50%; for asymptomatic patients: tight stenosis (>60%) and a perceived high long-term risk of stroke (determined mainly by imaging criteria). Choice of procedure may be influenced by anatomy (high stenosis, difficult CAS or CEA access, incomplete circle of Willis), prior illness or treatment (radiotherapy, other neck surgery), or patient risk (unable to lie flat, poor AHA assessment). In conclusion, neither systematic nor abandoned, the place of carotid revascularization must necessarily be limited to the plaques at highest risk, leaving a large place for optimized medical treatment as first line management. An evaluation of the value of performing endarterectomy on plaques considered to be at high risk is currently underway in the ACTRIS and CREST 2 studies. These studies, along with the next result of ACST-2 trial, will provide us a more precise strategy in case of carotid stenosis.

Perioperative management of venous recanalization in a patient with inherited antithrombin deficiency: case report.

Background: Inherited antithrombin (AT) deficiency (ATD) is a severe thrombophilia causing venous thromboembolism, which can be complicated by postthrombotic syndrome (PTS). Venous recanalization, used to treat PTS, often requires a temporary withdrawal of anticoagulant therapy. In ATD patients, there is a risk of insufficient perioperative anticoagulation due to altered heparin response. Key Clinical Question: There is no consensus on how to manage perioperative anticoagulation in ATD patients. Clinical Approach: Warfarin-unfractionated heparin transition could be a more reliable strategy than low-molecular-weight heparin transition because unfractionated heparin anti-Xa activity not only reflects heparin-bound AT but also AT's activity, which correlates strongly with therapeutic anticoagulation. Biological monitoring could thus decrease the number of plasma-derived AT supplementation. Conclusion: This study describes a successful perioperative management of anticoagulation for venous recanalization that could be suggested to type 1 ATD patients with PTS.

Acute phase determinant of post-thrombotic syndrome: A review of the literature.

BACKGROUND: Post-thrombotic syndrome (PTS) is the main long-term complication of deep vein thrombosis (DVT). Several therapies are being evaluated to prevent or to treat PTS. Identifying the patients most likely to benefit from these therapies presents a significant challenge. OBJECTIVES: The objective of this review was to identify risk factors for PTS during the acute phase of DVT. ELIGIBILITY CRITERIA: We searched the PubMed and Cochrane databases for studies published between January 2000 and January 2021, including randomized clinical trials, meta-analyses, systematic reviews and observational studies. RESULTS: Risk factors for PTS such as proximal location of DVT, obesity, chronic venous disease, history of DVT are associated with higher risk of PTS. On the initial ultrasound-Doppler, a high thrombotic burden appears to be a predictor of PTS. Among the evaluated biomarkers, some inflammatory markers such as ICAM-1, MMP-1 and MMP-8 appear to be associated with a higher risk of developing PTS. Coagulation disorders are not associated with risk of developing PTS. Role of endothelial biomarkers in predicting PTS has been poorly explored. Lastly, vitamin K antagonist was associated with a higher risk of developing PTS when compared to direct oral anticoagulants and low molecular weight heparin. CONCLUSIONS: Several risk factors during the acute phase of VTE are associated with an increased risk of developing PTS. There is a high-unmet medical need to identify potential biomarkers for early detection of patients at risk of developing PTS after VTE. Inflammatory and endothelial biomarkers should be explored in larger prospective studies to identify populations that could benefit from new therapies.

Role of the advanced nurse practitioner within the vascular team: A qualitative study of vascular physicians and nurses.

Objective: To assess the perception of Advanced Nurse Practitioners (ANP) by physicians and nurses in vascular medicine. As the status of ANP in France was recently enacted by law in 2018, we aimed to investigate physicians and nurses working with patients suffering from Peripheral Artery Disease (PAD) to gather their opinions and draw the cooperation outlines these practitioners could have with an ANP. Methods: A qualitative study based on in-depth interviews was conducted among healthcare practitioners taking care of patients with PAD: 10 physicians working either in a private practice settings or hospital settings or both, and eight nurses working within a hospital inpatients vascular unit. Verbatim responses were extracted and coded according to a continuous thematization method. Results: Three main features emerged from participants' responses. Vascular medicine has a specific organization with a significant lack of time and staff to fulfill the mission regarding patients' severity of illness. Second, the ANP is wanted to fill part of this gap. The expected benefits include a smoother care pathway and increased capacity for cardiovascular education and prevention, especially during consultations. Lastly, some clarification is required to integrate such new practitioners within vascular teams already in place. Conclusion: Advanced nurse practitioners could be the missing link in a "Vascular team" by creating a continuum in the care of patients with PAD, ensuring clinical assessment, nursing supervision, adverse event screening, and renewing drug prescriptions with the required adaptations while ensuring essential part of therapeutic education adapted to each patient.

Assessment of Takayasu's arteritis activity by ultrasound localization microscopy.

BACKGROUND: Ultrasound localization microscopy (ULM) based on ultrafast ultrasound imaging of circulating microbubbles (MB) can image microvascular blood flows in vivo up to the micron scale. Takayasu arteritis (TA) has an increased vascularisation of the thickened arterial wall when active. We aimed to perform vasa vasorum ULM of the carotid wall and demonstrate that ULM can provide imaging markers to assess the TA activity. METHODS: Patients with TA were consecutively included with assessment of activity by the National Institute of Health criteria: 5 had active TA (median age 35.8 [24.5-46.0] years) and 11 had quiescent TA (37.2 [31.7-47.3] years). ULM was performed using a 6.4 MHz probe and a dedicated imaging sequence (plane waves with 8 angles, frame rate 500 Hz), coupled with the intravenous injection of MB. Individual MB were localised at a subwavelength scale then tracked, allowing the reconstruction of the vasa vasorum flow anatomy and velocity. FINDINGS: ULM allowed to show microvessels and to measure their flow velocity within the arterial wall. The number of MB detected per second in the wall was 121 [80-146] in active cases vs. 10 [6-15] in quiescent cases (p = 0.0005), with a mean velocity of 40.5 [39.0-42.9] mm.s-1 in active cases. INTERPRETATION: ULM allows visualisation of microvessels within the thickened carotid wall in TA, with significantly greater MB density in active cases. ULM provides a precise visualisation in vivo of the vasa vasorum and gives access to the arterial wall vascularisation quantification. FUNDING: French Society of Cardiology. ART (Technological Research Accelerator) biomedical ultrasound program of INSERM, France.

Effect of weight-adjusted intermediate-dose versus fixed-dose prophylactic anticoagulation with low-molecular-weight heparin on venous thromboembolism among noncritically and critically ill patients with COVID-19: the COVI-DOSE trial, a multicenter, randomised, open-label, phase 4 trial.

Background: Venous thromboembolism is a major complication of coronavirus disease 2019 (COVID-19). We hypothesized that a weight-adjusted intermediate dose of anticoagulation may decrease the risk of venous thromboembolism COVID-19 patients. Methods: In this multicenter, randomised, open-label, phase 4, superiority trial with blinded adjudication of outcomes, we randomly assigned adult patients hospitalised in 20 French centers and presenting with acute respiratory SARS-CoV-2. Eligible patients were randomly assigned (1:1 ratio) to receive an intermediate weight-adjusted prophylactic dose or a fixed-dose of subcutaneous low-molecular-weight heparin during the hospital stay. The primary outcome corresponded to symptomatic deep-vein thrombosis (fatal) pulmonary embolism during hospitalization (COVI-DOSE ClinicalTrials.gov number: NCT04373707). Findings: Between May 2020, and April 2021, 1000 patients underwent randomisation in medical wards (noncritically ill) (80.1%) and intensive care units (critically ill) (19.9%); 502 patients were assigned to receive a weight-adjusted intermediate dose, and 498 received fixed-dose thromboprophylaxis. Symptomatic venous thromboembolism occurred in 6 of 502 patients (1.2%) in the weight-adjusted dose group and in 10 of 498 patients (2.1%) in the fixed-dose group (subdistribution hazard ratio, 0.59; 95% CI, 0.22-1.63; P = 0.31). There was a twofold increased risk of major or clinically relevant nonmajor bleeding: 5.9% in the weight-adjusted dose group and 3.1% in the fixed-dose group (P = 0.034). Interpretation: In the COVI-DOSE trial, the observed rate of thromboembolic events was lower than expected in patients hospitalized for COVID-19 infection, and the study was unable to show a significant difference in the risk of venous thromboembolism between the two low-molecular-weight-heparin regimens. Funding: French Ministry of Health, CAPNET, Grand-Est Region, Grand-Nancy Métropole.

D-dimer testing in clinical practice in the era of COVID-19.

D-dimer is a fragment of crosslinked fibrin resulting from plasmin cleavage of fibrin clots and hence an indirect biomarker of the hemostatic system activation. Early in the coronavirus disease 2019 (COVID-19) pandemic, several studies described coagulation disorders in affected patients, including high D-dimer levels. Consequently, D-dimer has been widely used in not-yet-approved indications. Ruling out pulmonary embolism and deep vein thrombosis in patients with low or intermediate clinical suspicion is the main application of D-dimer. D-dimer is also used to estimate the risk of venous thromboembolism recurrence and is included in the ISTH algorithm for the diagnosis of disseminated intravascular coagulation. Finally, numerous studies identified high D-dimer levels as a biomarker of poor prognosis in hospitalized patients with COVID-19. This report focuses on validated applications of D-dimer testing in patients with and without COVID-19.

Women Specific Characteristics and 1-Year Outcome Among Patients Hospitalized for Peripheral Artery Disease: A Monocentric Cohort Analysis in a Tertiary Center.

Although women have lower age-standardized cardiovascular disease incidence, prevalence, and death-related rates than men, there are also reports indicating that women with cardiovascular disease receive less care, fewer investigations, and have poorer outcomes after a coronary event. The aims of this study were to compare the characteristics of men and women hospitalized for peripheral artery disease (PAD), their cardiovascular and limb outcomes, and their 1-year mortality. The study is a prospective registry collecting data about all consecutive patients hospitalized for PAD within the vascular department of the tertiary center Georges-Pompidou European Hospital (Paris, France). Patients were required to have one of three inclusion criteria: previous revascularization of the lower limb or any lower limb artery occlusion due to an atherosclerotic vascular disease or hemodynamic evidence of PAD. Exclusion criteria were patients with lower extremity arterial occlusion due to another cause. All patients were followed-up for at least 12 months after the initial hospitalization. Among the 235 patients included, there were 61 women (26%), older than men with a median age of 75.6 and 68.3 years, respectively. Main cardiovascular risk factors and comorbidities were similar for men and women except more former or current smokers [145 (83.4%) vs. 33 (54.1%)] and more history of coronary heart disease [42 (24.1%) vs. 7 (11.5%)] in men. Most patients [138 (58.8%)] had critical limb ischemia and 97 (41.3%) had claudication, with no difference for sex. After discharge, 218 patients received an antithrombotic therapy (93.2%), 195 a lipid-lowering drug (83.3%), 185 an angiotensin converting enzyme inhibitor or angiotensin-receptor blocker (78.9%), similarly between sex. At 1-year, overall mortality, major adverse cardiovascular events, major adverse limb events did not differ with 23 (13.2%), 11 (6.3%) and 32 (18.4%) in men, and 8 (13.1%), 3 (4.9%), 15 (24.6%) in women, respectively, despite the difference in age. Overall mortality, cardiovascular outcomes, limb revascularization or amputation did not differ between men and women, 1-year after hospitalization for PAD although the latter were older, less smoker and had less coronary artery disease. Due to the small size of this cohort, larger studies and future research are needed to better understand sex-specific mechanisms in the pathophysiology and natural history of PAD.

Carotid Plaque Vulnerability Assessed by Combined Shear Wave Elastography and Ultrafast Doppler Compared to Histology.

Ultrafast ultrasound imaging (UUI) provides an estimation of carotid plaque stiffness by shear wave elastography (SWE) and the quantification of wall shear stress (WSS) by ultrafast Doppler. We aimed to evaluate the combined criteria of plaque stiffness and WSS applied on the plaque as potential biomarkers of plaque vulnerability assessed by histology. We included patients for whom carotid endarterectomy had been decided by a multidisciplinary team. UUI was performed within 48 h before surgery, and acquisitions were obtained on a carotid longitudinal view. After endarterectomy, gross examination and histological analysis were performed on each removed plaque. Forty-six plaques with SWE data and 29 with WSS data were analyzed. Histological analysis revealed 29 vulnerable and 17 stable plaques. Gray-scale median analysis by B-mode, mean, and standard deviation of stiffness by SWE did not differ between vulnerable and stable plaques. SWE analysis revealed that the percentage of stiffness range of 3-5 m/s was significantly increased in vulnerable plaques (p = 0.048). WSS alone showed no difference between stable and vulnerable plaques regardless of the segment of the plaque which was analyzed. A multiparametric score using maximal WSS at the peak of the plaque associated with SWE texture analysis parameters was calculated by stepwise regression, leading to a score with a sensitivity of 80% and a specificity of 78%. Area under the receiver operating characteristics curve was 0.85. A multiparameter scoring system including plaque stiffness and flow analysis using UUI allows to effectively identify histologically vulnerable carotid plaques. ClinicalTrials.gov Identifier: NCT03234257.

Adjusting D-dimer to Lung Disease Extent to Exclude Pulmonary Embolism in COVID-19 Patients (Co-LEAD).

OBJECTIVE: D-dimer measurement is a safe tool to exclude pulmonary embolism (PE), but its specificity decreases in coronavirus disease 2019 (COVID-19) patients. Our aim was to derive a new algorithm with a specific D-dimer threshold for COVID-19 patients. METHODS: We conducted a French multicenter, retrospective cohort study among 774 COVID-19 patients with suspected PE. D-dimer threshold adjusted to extent of lung damage found on computed tomography (CT) was derived in a patient set (n = 337), and its safety assessed in an independent validation set (n = 337). RESULTS: According to receiver operating characteristic curves, in the derivation set, D-dimer safely excluded PE, with one false negative, when using a 900 ng/mL threshold when lung damage extent was <50% and 1,700 ng/mL when lung damage extent was ≥50%. In the derivation set, the algorithm sensitivity was 98.2% (95% confidence interval [CI]: 94.7-100.0) and its specificity 28.4% (95% CI: 24.1-32.3). The negative likelihood ratio (NLR) was 0.06 (95% CI: 0.01-0.44) and the area under the curve (AUC) was 0.63 (95% CI: 0.60-0.67). In the validation set, sensitivity and specificity were 96.7% (95% CI: 88.7-99.6) and 39.2% (95% CI: 32.2-46.1), respectively. The NLR was 0.08 (95% CI; 0.02-0.33), and the AUC did not differ from that of the derivation set (0.68, 95% CI: 0.64-0.72, p = 0.097). Using the Co-LEAD algorithm, 76 among 250 (30.4%) COVID-19 patients with suspected PE could have been managed without CT pulmonary angiography (CTPA) and 88 patients would have required two CTs. CONCLUSION: The Co-LEAD algorithm could safely exclude PE, and could reduce the use of CTPA in COVID-19 patients. Further prospective studies need to validate this strategy.

Dealiasing High-Frame-Rate Color Doppler Using Dual-Wavelength Processing.

Doppler ultrasound is the premier modality to analyze blood flow dynamics in clinical practice. With conventional systems, Doppler can either provide a time-resolved quantification of the flow dynamics in sample volumes (spectral Doppler) or an average Doppler velocity/power [color flow imaging (CFI)] in a wide field of view (FOV) but with a limited frame rate. The recent development of ultrafast parallel systems made it possible to evaluate simultaneously color, power, and spectral Doppler in a wide FOV and at high-frame rates but at the expense of signal-to-noise ratio (SNR). However, like conventional Doppler, ultrafast Doppler is subject to aliasing for large velocities and/or large depths. In a recent study, staggered multi-pulse repetition frequency (PRF) sequences were investigated to dealias color-Doppler images. In this work, we exploit the broadband nature of pulse-echo ultrasound and propose a dual-wavelength approach for CFI dealiasing with a constant PRF. We tested the dual-wavelength bandpass processing, in silico, in laminar flow phantom and validated it in vivo in human carotid arteries ( n = 25 ). The in silico results showed that the Nyquist velocity could be extended up to four times the theoretical limit. In vivo, dealiased CFI were highly consistent with unfolded Spectral Doppler ( r2=0.83 , y=1.1x+0.1 , N=25 ) and provided consistent vector flow images. Our results demonstrate that dual-wavelength processing is an efficient method for high-velocity CFI.

Thrombus of the Aorta and SARS-CoV-2 Infection: Cause or Trigger?

Objective: Coronavirus disease 19 is a well-established cause of rare arterial thrombosis. Nevertheless, the exact mechanism of arterial thrombosis remains to be elucidated. We herein report the case of a large floating thrombus of the aortic arch, its surgical management and histological analysis. Case: A 65-year-old patient presented to the emergency department with a suspected stroke. He was non-smoker, but presented cardiovascular risk factors, namely hypertension, type 2 diabetes and hyperlipidaemia. A computed tomography of the aorta revealed a large floating thrombus of the aortic arch, at the base of the brachiocephalic trunk, suspected to be the etiology of stroke. Therapeutic anticoagulation was immediately started. The decision was made to perform an open aortic replacement surgery because of the symptomatic thromboembolic event with recent cerebral infarction and the potential harmfulness of the thrombus due to its size. A mobile thrombus was observed at the base of the brachiocephalic trunk by echocardiography. It was attached to a small area of the upper aortic wall and had an irregular surface. Histology revealed a platelet-rich thrombus lying on an aortic atherosclerotic plaque without pronounced inflammation. No plaque ulceration was present but endothelial cell desquamation was observed consistent with plaque erosion. Conclusion: In our case, there was a thrombus lying on an atherosclerotic plaque with intact thick fibrous cap, but associated with a plaque erosion mechanism. The thrombus formation appeared more likely to relate to a very localized endothelial injury.

Intermediate- vs. Standard-Dose Prophylactic Anticoagulation in Patients With COVID-19 Admitted in Medical Ward: A Propensity Score-Matched Cohort Study.

Background: Microthrombosis and large-vessel thrombosis are the main triggers of COVID-19 worsening. The optimal anticoagulant regimen in COVID-19 patients hospitalized in medical wards remains unknown. Objectives: To evaluate the effects of intermediate-dose vs. standard-dose prophylactic anticoagulation (AC) among patients with COVID-19 hospitalized in medical wards. Methods and results: We used a large French multicentric retrospective study enrolling 2,878 COVID-19 patients hospitalized in medical wards. After exclusion of patients who had an AC treatment before hospitalization, we generated a propensity-score-matched cohort of patients who were treated with intermediate-dose or standard-dose prophylactic AC between February 26 and April 20, 2020 (intermediate-dose, n = 261; standard-dose prophylactic anticoagulation, n = 763). The primary outcome of the study was in-hospital mortality; this occurred in 23 of 261 (8.8%) patients in the intermediate-dose group and 74 of 783 (9.4%) patients in the standard-dose prophylactic AC group (p = 0.85); while time to death was also the same in both the treatment groups (11.5 and 11.6 days, respectively, p = 0.17). We did not observe any difference regarding venous and arterial thrombotic events between the intermediate dose and standard dose, respectively (venous thrombotic events: 2.3 vs. 2.4%, p=0.99; arterial thrombotic events: 2.7 vs. 1.2%, p = 0.25). The 30-day Kaplan-Meier curves for in-hospital mortality demonstrate no statistically significant difference in in-hospital mortality (HR: 0.99 (0.63-1.60); p = 0.99). Moreover, we found that no particular subgroup was associated with a significant reduction in in-hospital mortality. Conclusion: Among COVID-19 patients hospitalized in medical wards, intermediate-dose prophylactic AC compared with standard-dose prophylactic AC did not result in a significant difference in in-hospital mortality.