Comparison between different referral strategies for acute ischemic stroke patients in a hub-spoke emergency stroke network: a real-world experience in south-east Lazio

AIM

To describe different referral strategies for acute ischemic stroke (AIS) patients in a Hub-Spoke emergency stroke network with their incidence, time metrics and related outcomes.

METHODS

Referral paradigms were defined as follows: primary transfer to the comprehensive stroke center (CSC) from a remote region, called mothership (MS); secondary transfer to the CSC from a primary stroke center where intravenous thrombolysis was available, called drip and ship (DS); secondary transfer to the CSC from a community hospital where no reperfusion therapy was available, called ship and drip (SD); primary transfer to the CSC from its catchment area, called direct CSC (dCSC).

RESULTS

Among 517 anterior circulation AIS patients treated with mechanical thrombectomy between 2015 and 2020, 16.6% of them were SD, in addition to the well-known referral paradigms of MS (21.8%) and DS (18.1%). This rate grew to 30% when only patients whose place of onset was outside the CSC catchment area were considered. In the SD group, onset to CSC and onset to groin were significantly longer (178±80 min vs. 102±60 min, p<0.001, and 277±77 min vs. 211±61 min, p<0.001, respectively), and the risk of any intracranial hemorrhage (ICH) was significantly higher (OR: 2.514; 95%CI: 1.18-5.35, p=0.017) compared to MS.

CONCLUSION

In this hub-spoke stroke network, a high proportion of SD paradigm was found, which was associated with longer times to treatment and higher rates of any ICH. A closer cooperation between hospital stroke physicians, national health system staff, and paramedics is warranted to identify the most appropriate referral strategy for each patient.

Ozone eliminates novel coronavirus Sars-CoV-2 in mucosal samples

Recent investigations have shown that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is able to resist on the surfaces and that the diffusion occurs through droplets that can remain suspended in the air as an aerosol. The ozone generated in situ from oxygen is an active ingredient with a 'biocidal' action, but little is known about its capacity to inactivate specifically SARS-CoV-2. Here we show, for the first time, the efficiency of the ozone treatment to neutralize the SARS-CoV-2 present in nasopharynx secretion samples with high viral load. Our data show that ozone is effective in SARS-CoV-2 elimination.

Severe acute respiratory syndrome coronavirus 2 may exploit human transcription factors involved in retinoic acid and interferon-mediated response: a hypothesis supported by an in silico analysis

The pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causing coronavirus disease 2019 (COVID-19), resulting in acute respiratory disease, is a worldwide emergency. Because recently it has been found that SARS-CoV is dependent on host transcription factors (TF) to express the viral genes, efforts are required to understand the molecular interplay between virus and host response. By bioinformatic analysis, we investigated human TF that can bind the SARS-CoV-2 sequence and can be involved in viral transcription. In particular, we analysed the key role of TF involved in interferon (IFN) response. We found that several TF could be induced by the IFN antiviral response, specifically some induced by IFN-stimulated gene factor 3 (ISGF3) and by unphosphorylated ISGF3, which were found to promote the transcription of several viral open reading frame. Moreover, we found 22 TF binding sites present only in the sequence of virus infecting humans but not bat coronavirus RaTG13. The 22 TF are involved in IFN, retinoic acid signalling and regulation of transcription by RNA polymerase II, thus facilitating its own replication cycle. This mechanism, by competition, may steal the human TF involved in these processes, explaining SARS-CoV-2's disruption of IFN-I signalling in host cells and the mechanism of the SARS retinoic acid depletion syndrome leading to the cytokine storm. We identified three TF binding sites present exclusively in the Brazilian SARS-CoV-2 P.1 variant that may explain the higher severity of the respiratory syndrome. These data shed light on SARS-CoV-2 dependence from the host transcription machinery associated with IFN response and strengthen our knowledge of the virus's transcription and replicative activity, thus paving the way for new targets for drug design and therapeutic approaches.

Impact of old and very old age on outcomes in patients with acute ischemic stroke undergoing endovascular therapy

Background and purpose

Only a restricted number of elderly patients has been included in the majority of recent endovascular stroke trials. We provided an analysis about differences in outcomes after mechanical thrombectomy (MT) according to age.

Methods

A retrospective analysis of an observational registry of patients with anterior large vessel acute ischemic stroke was performed. Main analysis was performed comparing patients &lt;80 vs. ≥80 years old. A sensitivity analysis was performed comparing 3 age groups: i) &lt;80 years; ii) 80–84 years; iii) ≥85 years. Outcomes were: i) any hemorrhagic infarction; ii) alive with disability; iii) death; iv) a composite outcome of alive with disability/death.

Results

615 patients were identified. 227 (36.9%) patients were ≥80 years old, with 115 (18.5%) ≥85 years old. Elderly (≥80 years) patients showed a higher modified Rankin Scale (mRS) at discharge and 3-months follow-up (F=9.819, p=0.001) [Figure 1]. Comparing the three groups (&lt;80 years, 80–84 years, ≥85 years) a progressively higher mRS was found at discharge and 3 months follow-up (F=4.899, p=0.008). A progressively higher rate of death and composite outcome between the age groups was found, both in the main and sensitivity analyses. In the logistic regression analysis age ≥80 years was found associated with an increased risk of death (odds ratio [OR]: 2.25, 95% confidence interval [CI]: 1.27–4.00) and showed a trend in higher risk for composite outcome (OR: 1.61, 95% CI: 0.92–2.281). No difference was found between 80–84 years and &lt;80 years patients, while very elderly (≥85 years) had an increased risk of death (OR: 2.85, 95% CI: 1.60–5.10) and composite outcome (OR: 2.37, 95% CI: 1.30–4.33).

Conclusions

In our analysis elderly patients have an increased risk of death and composite outcome of disability and death. In particular, this risk appears to be significantly higher in very elderly patients (≥85 years old).

Figure 1. mRS according to main analysis

Funding Acknowledgement

Type of funding source: None

Functional and radiological outcomes after bridging therapy versus direct thrombectomy in stroke patients with unknown onset: Bridging therapy versus direct thrombectomy in unknown onset stroke patients with 10-point ASPECTS

BACKGROUND AND PURPOSE

The aim was to assess functional and radiological outcomes after bridging therapy (intravenous thrombolysis plus mechanical thrombectomy) versus direct mechanical thrombectomy (MT) in unknown onset stroke patients.

METHODS

A cohort study was conducted on prospectively collected data from unknown onset stroke patients who received endovascular procedures at ≤6 h from symptom recognition or awakening time.

RESULTS

Of the 349 patients with a 10-point Alberta Stroke Program Early Computed Tomography Score (ASPECTS), 248 received bridging and 101 received direct MT. Of the 134 patients with 6-9-point ASPECTS, 123 received bridging and 111 received direct MT. Each patient treated with bridging was propensity score matched with a patient treated with direct MT for age, sex, study period, pre-stroke disability, stroke severity, type of stroke onset, symptom recognition to groin time (or awakening to groin time), ASPECTS and procedure time. In the two matched groups with 10-point ASPECTS (n = 73 vs. n = 73), bridging was associated with higher rates of excellent outcome (46.6% vs. 28.8%; odds ratio 2.302, 95% confidence interval 1.010-5.244) and successful recanalization (83.6% vs. 63%; odds ratio 3.028, 95% confidence interval 1.369-6.693) compared with direct MT; no significant association was found between bridging and direct MT with regard to rate of symptomatic intracerebral hemorrhage (0% vs. 1.4%). In the two matched groups with 6-9-point ASPECTS (n = 45 vs. n = 45), no significant associations were found between bridging and direct MT with regard to rates of excellent functional outcome (44.4% vs. 31.1%), successful recanalization (73.3% vs. 76.5%) and symptomatic intracerebral hemorrhage (0% vs. 0%).

CONCLUSIONS

Bridging at ≤ 6 h of symptom recognition or awakening time was associated with better functional and radiological outcomes in unknown onset stroke patients with 10-point ASPECTS.

Carotid Stenting and Mechanical Thrombectomy in Patients with Acute Ischemic Stroke and Tandem Occlusions: Antithrombotic Treatment and Functional Outcome

BACKGROUND AND PURPOSE

There is no consensus on the optimal antithrombotic medication for patients with acute ischemic stroke with anterior circulation tandem occlusions treated with emergent carotid stent placement and mechanical thrombectomy. The identification of factors influencing hemorrhagic risks can assist in creating appropriate therapeutic algorithms for such patients. This study aimed to investigate the impact of medical therapy on functional and safety outcomes in patients treated with carotid stent placement and mechanical thrombectomy for tandem occlusions.

MATERIALS AND METHODS

A multicenter retrospective study on prospectively collected data was conducted. Only patients treated with carotid stent placement and mechanical thrombectomy for tandem occlusions of the anterior circulation were included. Univariate and multivariate analyses were performed on preprocedural, procedural, and postprocedural variables to assess factors influencing clinical outcome, symptomatic intracranial hemorrhage, stent patency, and successful intracranial vessel recanalization.

RESULTS

Ninety-five patients with acute ischemic stroke and tandem occlusions were included. Good clinical outcome (mRS ≤ 2) at 3 months was reached by 33 (39.3%) patients and was associated with baseline ASPECTS ≥ 8 (OR = 1.53; 95% CI, 1.16-2.00), ≤2 mechanical thrombectomy attempts (OR = 0.71; 95% CI, 0.55-0.99), and the absence of symptomatic intracranial hemorrhage (OR = 0.13; 95% CI , 0.03-0.51). Symptomatic intracranial hemorrhage was associated with a higher amount of intraprocedural heparin, ASPECTS ≤ 7, and ≥3 mechanical thrombectomy attempts. No relationships among types of acute antiplatelet regimen, intravenous thrombolysis, and symptomatic intracranial hemorrhage were observed. Patients receiving dual-antiplatelet therapy after hemorrhagic transformation had been ruled out on 24-hour CT were more likely to achieve functional independence and had a lower risk of symptomatic intracranial hemorrhage.

CONCLUSIONS

During carotid stent placement and mechanical thrombectomy for tandem occlusion treatment, higher intraprocedural heparin dosage (≥3000 IU) increased symptomatic intracranial hemorrhage risk when the initial ASPECTS was ≤7, and mechanical thrombectomy needs more than one passage for complete recanalization. Antiplatelets antiplatelets use were safe, and dual-antiaggregation therapy was related to better functional outcomes.

CT Angiography ASPECTS Predicts Outcome Much Better Than Noncontrast CT in Patients with Stroke Treated Endovascularly

BACKGROUND AND PURPOSE

Noncontrast CT ASPECTS has been investigated as a predictor of outcome in patients with acute ischemic stroke. Our purpose was to investigate whether CTA source images are a better predictor of clinical and radiologic outcomes than NCCT ASPECTS in candidates for endovascular stroke therapy.

MATERIALS AND METHODS

CT scans of patients (n = 124) were independently evaluated by 2 readers for baseline NCCT and CTA source image ASPECTS and for follow-up ASPECTS. An mRS of ≤2 at 3 months was considered a favorable outcome. Receiver operating characteristic curve analysis was used to assess the ability of NCCT and CTA source image ASPECTS to identify patients with favorable outcomes. A stepwise multiple regression analysis was performed to find independent predictors of outcome.

RESULTS

Baseline CTA source image ASPECTS correlated better than NCCT ASPECTS with follow-up ASPECTS (r = 0.76 versus r = 0.51; P for comparison of the 2 coefficients < .001). Receiver operating characteristic curve analysis showed that baseline CTA source image ASPECTS compared with NCCT ASPECTS can better identify patients with favorable outcome (CTA source image area under the curve = 0.83; 95% CI, 0.76-0.91; NCCT area under the curve = 0.67; 95% CI, 0.58-0.77; P < .001). Finally, the stepwise regression analysis showed that lower age, good recanalization, lower time to recanalization, and good baseline CTA source image ASPECTS, not NCCT ASPECTS, were independent predictors of favorable outcome.

CONCLUSIONS

CTA source image ASPECTS predicts outcome better than NCCT ASPECTS; this finding suggests CTA rather than NCCT as a main step in the decision-making process for patients with acute ischemic stroke.

Multiple rare genetic variants co-segregating with familial IgA nephropathy all act within a single immune-related network

BACKGROUND

IgA nephropathy (IgAN) is a common complex disease with a strong genetic involvement. We aimed to identify novel, rare, highly penetrant risk variants combining family-based linkage analysis with whole-exome sequencing (WES).

METHODS

Linkage analysis of 16 kindreds of South Italian ancestry was performed using an 'affected-only' strategy. Eight most informative trios composed of two familial cases and an intrafamilial control were selected for WES. High-priority variants in linked regions were identified and validated using Sanger sequencing. Custom TaqMan assays were designed and carried out in the 16 kindreds and an independent cohort of 240 IgAN patients and 113 control subjects.

RESULTS

We found suggestive linkage signals in 12 loci. After sequential filtering and validation of WES data, we identified 24 private or extremely rare (MAF <0.0003) linked variants segregating with IgAN status. These were present within coding or regulatory regions of 23 genes that merged into a common functional network. The genes were interconnected by AKT, CTNNB1, NFKB, MYC and UBC, key modulators of WNT/β-catenin and PI3K/Akt pathways, which are implicated in IgAN pathogenesis. Overlaying publicly available expression data, genes/proteins with expression notably altered in IgAN were included in this immune-related network. In particular, the network included the glucocorticoid receptor gene, NR3C1, which is the target of corticosteroid therapy routinely used in the treatment of IgAN.

CONCLUSION

Our findings suggest that disease susceptibility could be influenced by multiple rare variants acting in a common network that could provide the starting point for the identification of potential drug targets for personalized therapy.

MicroRNAs in kidney diseases: new promising biomarkers for diagnosis and monitoring

A series of microRNAs (miRNAs) have a critical role in many cellular and physiological activities such as cell cycle, growth, proliferation, apoptosis and metabolism. miRNAs are also important in the maintenance of renal homeostasis and kidney diseases. In vitro and in vivo animal models have shown a critical role of miRNAs in the development of diabetic nephropathy (DN) and in the progression of renal fibrosis. Specific miRNAs in renal tissue and peripheral blood mononuclear cells (PBMCs) are up and downregulated in different kidney diseases. They represent new potential biomarkers for diagnosis and targeted therapy. In addition, urinary miRNAs may be considered non-invasive biomarkers for monitoring the progression of renal damage. The activity of miRNAs can be modified by different approaches such as the use of antisense oligonucleotide inhibitors (antagomirs), tandem miRNA-binding site repeats manufactured by Decoy or Sponge technologies and miRNA mimics. The use of miRNA blockers or antagonists as therapeutic agents is very attractive but new information will be necessary considering their role in other systems.

Pharmacogenomics: a new paradigm to personalize treatments in nephrology patients

Although notable progress has been made in the therapeutic management of patients with chronic kidney disease in both conservative and renal replacement treatments (dialysis and transplantation), the occurrence of medication-related problems (lack of efficacy, adverse drug reactions) still represents a key clinical issue. Recent evidence suggests that adverse drug reactions are major causes of death and hospital admission in Europe and the United States. The reasons for these conditions are represented by environmental/non-genetic and genetic factors responsible for the great inter-patient variability in drugs metabolism, disposition and therapeutic targets. Over the years several genetic settings have been linked, using pharmacogenetic approaches, to the effects and toxicity of many agents used in clinical nephrology. However, these strategies, analysing single gene or candidate pathways, do not represent the gold standard, being the overall pharmacological effects of medications and not typically monogenic traits. Therefore, to identify multi-genetic influence on drug response, researchers and clinicians from different fields of medicine and pharmacology have started to perform pharmacogenomic studies employing innovative whole genomic high-throughput technologies. However, to date, only few pharmacogenomics reports have been published in nephrology underlying the need to enhance the number of projects and to increase the research budget for this important research field. In the future we would expect that, applying the knowledge about an individual's inherited response to drugs, nephrologists will be able to prescribe medications based on each person's genetic make-up, to monitor carefully the efficacy/toxicity of a given drug and to modify the dosage or number of medications to obtain predefined clinical outcomes.

Sildenafil increases cerebrovascular reactivity: A transcranial Doppler study

The authors performed a double-blind, placebo-controlled study in 28 patients to evaluate the effects of sildenafil on cerebral hemodynamics. A significant improvement of cerebrovascular reactivity, without any modification of other variables, was recorded 1 hour after the administration of 50 mg sildenafil. Further investigations are needed to evaluate whether cerebrovascular reactivity improvement could contribute to triggering sildenafil-induced migraine.