Thrombolysis and thrombectomy for stroke in octogenarians and nonagenarians: A regional observational study

INTRODUCTION

Elderly patients are a growing population in stroke units, characterized by higher frailty, but underrepresented in clinical trials about acute care. We investigated efficacy of intravenous thrombolysis (IVT) and mechanical thrombectomy (MT) in elderlies in current practice.

METHODS

We assessed consecutive patients with acute ischemic stroke (AIS) hospitalized in the four stroke units of the French Northern Alps Emergency Network between 2015 and 2020. We compared baseline characteristics, early neurological evolution and outcome of patients aged 80-89 and≥90years old (yo).

RESULTS

Among 8367 patients, 2744 (32.8%) were 80-89 yo and 541 (6.5%) were≥90 yo. IVT and/or MT were performed in 787 patients≥80 yo (632 patients aged 80-89, 155 patients aged>90). Early neurological improvement was more frequent in patients≥80 yo treated by IVT and/or MT compared to untreated patients (45.6% versus 38.4%, P=0.002). After adjustment, reperfusion treatments improved likelihood of good outcome at discharge (OR=2.0 [1.6-2.7]) and reduced in-hospital mortality (OR=0.5 [0.4-0.7]). Age and initial NIHSS score were independent factors of poor functional outcome at discharge and in-hospital mortality. The rate of successful recanalization was comparable between octogenarians and nonagenarians (87% versus 85.2%, P=0.8). Octogenarians had better functional outcome at discharge compared to nonagenarians [modified Rankin scale (mRS) 0-2: 36% versus 25.7%, P=0.02], whatever IVT or MT strategy. In-hospital mortality was lower for octogenarians compared to nonagenarians (19.5% versus 27.1%, P=0.04).

DISCUSSION

IVT and MT improve early neurological recovery and functional outcome at discharge of both octogenarians and nonagenarians in current practice. Despite a poorer outcome for nonagenarians than octogenarians, these reperfusion treatments should not be withheld on the basis of age only.

Angioedema associated with thrombolysis for ischemic stroke: analysis of a case-control study

BACKGROUND

Bradykinin-mediated angioedema (AE) is a complication associated with thrombolysis for acute ischemic stroke. Risk factors are unknown and management is discussed.

OBJECTIVES

To clarify risk factors associated with bradykinin-mediated AE after thrombolysis for acute ischemic stroke.

METHODS

In a case-control study conducted at a French reference centre for bradykinin angiœdema, patients with thrombolysis for acute ischemic stroke and a diagnosis of bradykinin-mediated angiœdema, were compared to controls treated with thrombolysis treatment without angiœdema.

RESULTS

Fifty-three thrombolysis-related AE were matched to 106 control subjects. The sites of attacks following thrombolysis for ischemic stroke mainly included tongue (34/53, 64%) and lips (26/53, 49%). The upper airways were involved in 37 (70%) cases. Three patients required mechanical ventilation. Patients with bradykinin-mediated angiœdema were more frequently women [33 (62%) vs. 44 (42%); P = 0.01], had higher frequency of prior ischemic stroke [12 (23%) vs. 9 (8%); P = 0.01], hypertension [46 (87%) vs. 70 (66%); P = 0.005], were more frequently treated with angiotensin-converting enzyme inhibitor [37 (70%) vs. 28 (26%); P < 0.001] and were more frequently hospitalized in intensive care medicine [ICU; 11 (21%) vs. 5 (5%); P = 0.004]. In multivariate analysis, factors associated with thrombolysis-related AE were female sex [odds ratio (OR), 3.04; 95% confident interval (CI), 1.32-7.01; P = 0.009] and treatment with angiotensin-converting enzyme inhibitors [(OR), 6.08; 95% (CI), 2.17-17.07; P < 0.001].

CONCLUSIONS

This case-control study points out angiotensin-converting enzyme inhibitors and female sex as risk factors of bradykinin AE associated with thrombolysis for ischemic stroke.

Improving Access to Thrombolysis and Inhospital Management Times in Ischemic Stroke: A Stepped-Wedge Randomized Trial

BACKGROUND AND PURPOSE

A suboptimal number of ischemic stroke patients eligible for thrombolysis actually receive it, partly because of extended inhospital delays. We developed a comprehensive program designed for emergency unit staff and evaluated its effectiveness for reducing intrahospital times and improving access to thrombolysis.

METHODS

We conducted a randomized stepped-wedge controlled trial in 18 emergency unit. The sequentially implemented training intervention, targeting emergency physicians and nurses, was based on specifically designed videos and interactive simulation workshops on intrahospital management optimization. The effectiveness was assessed on intrahospital times and thrombolysis proportion. During the study period, all consecutive patients with confirmed ischemic stroke and no contraindications to thrombolysis were included.

RESULTS

A total of 328 patients were enrolled in the control group and 363 in the intervention group. Mean age was 73.6 years. Overall thrombolysis proportion was 34.2% in the intervention group versus 25.6% in the control group (adjusted odds ratio, 1.42; 95% confidence interval, 1.01-2.01), thrombolysis proportion within 4 hours 30 minutes almost doubled (adjusted odds ratio, 1.9; 95% confidence interval, 1.32-2.73). Although imaging-to-stroke unit time was significantly decreased in the intervention group (39 versus 53 minutes; P=0.03), median door-to-imaging and door-to-needle times were not different between groups (P=0.70 and P=0.40, respectively).

CONCLUSIONS

An interactive and multifaceted training program targeting emergency professionals was significantly associated with an increased access to thrombolysis, especially within 4 hours and 30 minutes.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT02814760.

Patient eligibility for thrombectomy after acute stroke: Northern French Alps database analysis

BACKGROUND

Since 2015, the emergence of mechanical thrombectomy as standard care in acute stroke has involved organizational changes not only for stroke centers, but also for entire emergency regional networks. The aim of our study was to assess the proportion of ischemic stroke patients, admitted to stroke units in the Northern French Alps within the first 6h of onset, eligible for thrombectomy.

METHODS

This study retrospectively analyzed the clinical and radiological data of all acute stroke patients hospitalized at three stroke units of the Northern French Alps Emergency Network (RENAU) in 2014. Eligible patients had proximal arterial occlusions of the anterior and posterior cerebral circulation, as confirmed by brain imaging, which could be treated by thrombectomy within 6h of symptom onset.

RESULTS

Of the 435 cases of acute ischemic stroke, 152 patients were treated by intravenous thrombolysis (IV rtPA). Of these patients, 83 (55%) had intracranial occlusions and were eligible for combined thrombectomy. Of the 283 patients not treatable by IV rtPA, 32 patients (11%) were eligible for primary thrombectomy.

CONCLUSION

Thrombectomy could be performed in 26% of our acute ischemic stroke patients (n=115/435), and a large increase in endovascular procedures is expected over the next few years that will require close collaboration among all partners in the emergency networks. Using our RENAU stroke database, it will be possible to compare various factors contributing to effective activity.

Image Quality Assessment for Fake Biometric Detection: Application to Iris, Fingerprint, and Face Recognition

To ensure the actual presence of a real legitimate trait in contrast to a fake self-manufactured synthetic or reconstructed sample is a significant problem in biometric authentication, which requires the development of new and efficient protection measures. In this paper, we present a novel software-based fake detection method that can be used in multiple biometric systems to detect different types of fraudulent access attempts. The objective of the proposed system is to enhance the security of biometric recognition frameworks, by adding liveness assessment in a fast, user-friendly, and non-intrusive manner, through the use of image quality assessment. The proposed approach presents a very low degree of complexity, which makes it suitable for real-time applications, using 25 general image quality features extracted from one image (i.e., the same acquired for authentication purposes) to distinguish between legitimate and impostor samples. The experimental results, obtained on publicly available data sets of fingerprint, iris, and 2D face, show that the proposed method is highly competitive compared with other state-of-the-art approaches and that the analysis of the general image quality of real biometric samples reveals highly valuable information that may be very efficiently used to discriminate them from fake traits.

A scalable formulation of probabilistic linear discriminant analysis: applied to face recognition

In this paper, we present a scalable and exact solution for probabilistic linear discriminant analysis (PLDA). PLDA is a probabilistic model that has been shown to provide state-of-the-art performance for both face and speaker recognition. However, it has one major drawback: At training time estimating the latent variables requires the inversion and storage of a matrix whose size grows quadratically with the number of samples for the identity (class). To date, two approaches have been taken to deal with this problem, to 1) use an exact solution that calculates this large matrix and is obviously not scalable with the number of samples or 2) derive a variational approximation to the problem. We present a scalable derivation which is theoretically equivalent to the previous nonscalable solution and thus obviates the need for a variational approximation. Experimentally, we demonstrate the efficacy of our approach in two ways. First, on labeled faces in the wild, we illustrate the equivalence of our scalable implementation with previously published work. Second, on the large Multi-PIE database, we illustrate the gain in performance when using more training samples per identity (class), which is made possible by the proposed scalable formulation of PLDA.

Human endogenous retrovirus type W envelope expression in blood and brain cells provides new insights into multiple sclerosis disease

Background:

The envelope protein from multiple sclerosis (MS) associated retroviral element (MSRV), a member of the Human Endogenous Retroviral family ‘W’ (HERV-W), induces dysimmunity and inflammation.

Objective:

The objective of this study was to confirm and specify the association between HERV-W/MSRV envelope (Env) expression and MS.

Methods:

103 MS, 199 healthy controls (HC) and controls with other neurological diseases (28), chronic infections (30) or autoimmunity (30) were analysed with an immunoassay detecting Env in serum. Env RNA or DNA copy numbers in peripheral blood mononuclear cells (PBMC) were determined by a quantitative polymerase chain reaction (PCR). Env was detected by immunohistology in the brains of patients with MS with three specific monoclonals.

Results:

Env antigen was detected in a serum of 73% of patients with MS with similar prevalence in all clinical forms, and not in chronic infection, systemic lupus, most other neurological diseases and healthy donors (p<0.01). Cases with chronic inflammatory demyelinating polyneuropathy (5/8) and rare HC (4/103) were positive. RNA expression in PBMC and DNA copy numbers were significantly elevated in patients with MS versus HC (p<0.001). In patients with MS, DNA copy numbers were significantly increased in chronic progressive MS (secondary progressive MS vs relapsing–remitting MS (RRMS) p<0.001; primary progressive MS vs RRMS –<0.02). Env protein was evidenced in macrophages within MS brain lesions with particular concentrations around vascular elements.

Conclusion:

The association between MS disease and the MSRV-type HERV-W element now appears quite strong, as evidenced ex-vivo from serum and PBMC with post-mortem confirmation in brain lesions. Chronic progressive MS, RRMS and clinically isolated syndrome show different ELISA (Enzyme-Linked Immunosorbent Assay) and/or PCR profiles suggestive of an increase with disease evolution, and amplicon sequencing confirms the association with particular HERV-W elements.

Person authentication using brainwaves (EEG) and maximum a posteriori model adaptation

In this paper, we investigate the use of brain activity for person authentication. It has been shown in previous studies that the brain-wave pattern of every individual is unique and that the electroencephalogram (EEG) can be used for biometric identification. EEG-based biometry is an emerging research topic and we believe that it may open new research directions and applications in the future. However, very little work has been done in this area and was focusing mainly on person identification but not on person authentication. Person authentication aims to accept or to reject a person claiming an identity, i.e., comparing a biometric data to one template, while the goal of person identification is to match the biometric data against all the records in a database. We propose the use of a statistical framework based on Gaussian Mixture Models and Maximum A Posteriori model adaptation, successfully applied to speaker and face authentication, which can deal with only one training session. We perform intensive experimental simulations using several strict train/test protocols to show the potential of our method. We also show that there are some mental tasks that are more appropriate for person authentication than others.

Multiple sclerosis retrovirus particles and recombinant envelope trigger an abnormal immune response in vitro, by inducing polyclonal Vbeta16 T-lymphocyte activation

A retroviral element (MSRV) defining a family of genetically inherited endogenous retroviruses (HERV-W) has recently been characterized in cell cultures from patients with multiple sclerosis (MS). To address the possible relationship with MS, direct detection of circulating virion RNA was proposed but revealed technically difficult to perform in standardized conditions, in the face of multiple endogenous HERV-W copies. A parallel approach has evaluated MSRV potential pathogenicity in relation to characteristic features of multiple sclerosis, in particular, T-lymphocyte-mediated immunopathology. We report here that MSRV particles induce T-lymphocyte response with a bias in the Vbeta16 chain usage in surface receptor, whatever the HLA DR of the donor. A recombinant MSRV envelope-but not core-protein reproduced similar nonconventional activation. Molecular analysis of Vbeta CDR3 showed that Vbeta16 expansions are polyclonal. Our results thus provide evidence that MSRV envelope protein can trigger an abnormal immune response with similar characteristics to that of superantigens.

[Myositis ossificans circumscripta and sequelae of muscular ischemia. 2 cases]

INTRODUCTION

Non-traumatic myositis ossificans circumscripta is a relatively rare, well defined entity. The pathogenic role of ischemia in its development is discussed.

EXEGESIS

We report two cases of myositis ossificans circumscripta that occurred in the hamstring muscle respectively 22 and 35 years after ischemic muscular injury in the same site. Clinical and radiologic informations and follow-up were reexamined, showing that patients are usually young and that the disease is equally distributed between both genders. Though the lesion may develop in various muscle, it is preferentially observed in proximal sites. Most patients have a history of localized pain or tenderness accompanied by swelling of the affected site. Following a 5- to 12-week increase, the soft-tissue mass is less sensitive and better defined. It may also resolve in less than 3 years.

CONCLUSION

Results of X rays, computerized tomography, MR imaging and biopsy are reviewed. Histologically, this lesion main feature is peripheral bone maturation within three areas. Mechanisms (traumatic or not) underlying these lesions are unknown. To our knowledge, only one published case would be comparable to ours. Proliferation followed by change in mesenchymal cells leading to heterotopic ossification must be regarded as a consequence of either ischemia or repeated micro-trauma occurring during muscle shortening.