Diagnostic accuracy of point-of-care ultrasound with artificial intelligence-assisted assessment of left ventricular ejection fraction

Focused cardiac ultrasound (FoCUS) is becoming standard practice in a wide spectrum of clinical settings. There is limited data evaluating the real-world use of FoCUS with artificial intelligence (AI). Our objective was to determine the accuracy of FoCUS AI-assisted left ventricular ejection fraction (LVEF) assessment and compare its accuracy between novice and experienced users. In this prospective, multicentre study, participants requiring a transthoracic echocardiogram (TTE) were recruited to have a FoCUS done by a novice or experienced user. The AI-assisted device calculated LVEF at the bedside, which was subsequently compared to TTE. 449 participants were enrolled with 424 studies included in the final analysis. The overall intraclass coefficient was 0.904, and 0.921 in the novice (n = 208) and 0.845 in the experienced (n = 216) cohorts. There was a significant bias of 0.73% towards TTE (p = 0.005) with a level of agreement of 11.2%. Categorical grading of LVEF severity had excellent agreement to TTE (weighted kappa = 0.83). The area under the curve (AUC) was 0.98 for identifying an abnormal LVEF (<50%) with a sensitivity of 92.8%, specificity of 92.3%, negative predictive value (NPV) of 0.97 and a positive predictive value (PPV) of 0.83. In identifying severe dysfunction (<30%) the AUC was 0.99 with a sensitivity of 78.1%, specificity of 98.0%, NPV of 0.98 and PPV of 0.76. Here we report that FoCUS AI-assisted LVEF assessments provide highly reproducible LVEF estimations in comparison to formal TTE. This finding was consistent among senior and novice echocardiographers suggesting applicability in a variety of clinical settings.

Evaluation of a Rabbit Model of Vascular Stent Healing: Application of Optical Coherence Tomography

Percutaneous coronary intervention (PCI) is a management strategy for symptomatic obstructive coronary artery disease (CAD). Despite advancements, in-stent restenosis (ISR) still imparts a 1-2% annual rate of repeat revascularization-a focus of ongoing translational research. Optical coherence tomography (OCT) provides high resolution virtual histology of stents. Our study evaluates the use of OCT for virtual histological assessment of stent healing in a rabbit aorta model, enabling complete assessment of intraluminal healing throughout the stent. ISR varies based on intra-stent location, stent length, and stent type in a rabbit model-important considerations for translational experimental design. Atherosclerosis leads to more prominent ISR proliferation independent of stent-related factors. The rabbit stent model mirrors clinical observations, while OCT-based virtual histology demonstrates utility for pre-clinical stent assessment. Pre-clinical models should incorporate clinical and stent factors as feasible to maximize translation to clinical practice.

Dipyridamole and vascular healing following stent implantation

Introduction

Patients undergoing coronary stent implantation incur a 2% annual rate of adverse events, largely driven by in-stent restenosis (ISR) due to neointimal (NI) tissue proliferation, a process in which smooth muscle cell (SMC) biology may play a central role. Dipyridamole (DP) is an approved therapeutic agent with data supporting improved vascular patency rates. Pre-clinical data supports that DP may enact its vasculoprotective effects via adenosine receptor-A2B (ADOR-A2B). We sought to evaluate the efficacy of DP to mitigate ISR in a pre-clinical rabbit stent model.

Methods & Results

24 New Zealand White Rabbits were divided into two cohorts-non-atherosclerosis and atherosclerosis (n = 12/cohort, 6 male and 6 female). Following stent implantation, rabbits were randomized 1:1 to control or oral dipyridamole therapy for 6 weeks followed by optical coherence tomography (OCT) and histology assessment of NI burden and stent strut healing. Compared to control, DP demonstrated a 16.6% relative reduction in NI volume (14.7 ± 0.8% vs. 12.5 ± 0.4%, p = 0.03) and a 36.2% relative increase in optimally healed stent struts (37.8 ± 2.8% vs. 54.6 ± 2.5%, p < 0.0001). Atherosclerosis demonstrated attenuated effect with no difference in NI burden (15.2 ± 1.0% vs. 16.9 ± 0.8%, p = 0.22) and only a 14.2% relative increase in strut healing (68.3 ± 4.1% vs. 78.7 ± 2.5%, p = 0.02). DP treated rabbits had a 44.6% (p = 0.045) relative reduction in NI SMC content. In vitro assessment of DP and coronary artery SMCs yielded dose-dependent reduction in SMC migration and proliferation. Selective small molecule antagonism of ADOR-A2B abrogated the effects of DP on SMC proliferation. DP modulated SMC phenotypic switching with ADOR-A2B siRNA knockdown supporting its role in the observed effects.

Conclusion

Dipyridamole reduces NI proliferation and improves stent healing in a preclinical model of stent implantation with conventional antiplatelets. Atherosclerosis attenuates the observed effect. Clinical trials of DP as an adjunctive agent may be warranted to evaluate for clinical efficacy in stent outcomes.

Rationale and Design of the Rivaroxaban Post-Transradial Access for the Prevention of Radial Artery Occlusion Trial (CAPITAL-RAPTOR)

INTRODUCTION

Transradial access (TRA) has rapidly emerged as the preferred vascular access site for coronary angiography and percutaneous coronary intervention. Radial artery occlusion (RAO) remains as an important complication of TRA as it precludes future ipsilateral transradial procedures. While intraprocedural anticoagulation has been studied extensively, the definitive role of postprocedural anticoagulation has not yet been established.

METHODS AND ANALYSIS

The Rivaroxaban Post-Transradial Access for the Prevention of Radial Artery Occlusion trial is a multicentre, prospective, randomised, open-label, blinded-endpoint design study investigating the efficacy and safety of rivaroxaban to reduce the incidence of RAO. Eligible patients will undergo randomisation to receive either rivaroxaban 15 mg once daily for 7 days or to no additional postprocedural anticoagulation. Doppler ultrasound to assess radial artery patency will be performed at 30 days.

ETHICS AND DISSEMINATION

The study protocol has been approved by the Ottawa Health Science Network Research Ethics Board (approval number 20180319-01H). The study results will be disseminated via conference presentations and peer-reviewed publications.

TRIAL REGISTRATION NUMBER

NCT03630055.

Predictors of Atrial Fibrillation in Patients With Stroke Attributed to Large- or Small-Vessel Disease: A Prespecified Secondary Analysis of the STROKE AF Randomized Clinical Trial

Importance

The Stroke of Known Cause and Underlying Atrial Fibrillation (STROKE AF) trial found that approximately 1 in 8 patients with recent ischemic stroke attributed to large- or small-vessel disease had poststroke atrial fibrillation (AF) detected by an insertable cardiac monitor (ICM) at 12 months. Identifying predictors of AF could be useful when considering an ICM in routine poststroke clinical care.

Objective

To determine the association between commonly assessed risk factors and poststroke detection of new AF in the STROKE AF cohort monitored by ICM.

Design, Setting, and Participants

This was a prespecified analysis of a randomized (1:1) clinical trial that enrolled patients between April 1, 2016, and July 12, 2019, with primary follow-up through 2020 and mean (SD) duration of 11.0 (3.0) months. Eligible patients were selected from 33 clinical research sites in the US. Patients had an index stroke attributed to large- or small-vessel disease and were 60 years or older or aged 50 to 59 years with at least 1 additional stroke risk factor. A total of 496 patients were enrolled, and 492 were randomly assigned to study groups (3 did not meet inclusion criteria, and 1 withdrew consent). Patients in the ICM group had the index stroke within 10 days before insertion. Data were analyzed from October 8, 2021, to January 28, 2022.

Interventions

ICM monitoring vs site-specific usual care (short-duration external cardiac monitoring).

Main Outcomes and Measures

The ICM device automatically detects AF episodes 2 or more minutes in length; episodes were adjudicated by an expert committee. Cox regression multivariable modeling included all parameters identified in the univariate analysis having P values <.10. AF detection rates were calculated using Kaplan-Meier survival estimates.

Results

The analysis included the 242 participants randomly assigned to the ICM group in the STROKE AF study. Among 242 patients monitored with ICM, 27 developed AF (mean [SD] age, 66.6 [9.3] years; 144 men [60.0%]; 96 [40.0%] women). Two patients had missing baseline data and exited the study early. Univariate predictors of AF detection included age (per 1-year increments: hazard ratio [HR], 1.05; 95% CI, 1.01-1.09; P = .02), CHA2DS2-VASc score (per point: HR, 1.54; 95% CI, 1.15-2.06; P = .004), chronic obstructive pulmonary disease (HR, 2.49; 95% CI, 0.86-7.20; P = .09), congestive heart failure (CHF; with preserved or reduced ejection fraction: HR, 6.64; 95% CI, 2.29-19.24; P < .001), left atrial enlargement (LAE; HR, 3.63; 95% CI, 1.55-8.47; P = .003), QRS duration (HR, 1.02; 95% CI, 1.00-1.04; P = .04), and kidney dysfunction (HR, 3.58; 95% CI, 1.35-9.46; P = .01). In multivariable modeling (n = 197), only CHF (HR, 5.06; 95% CI, 1.45-17.64; P = .05) and LAE (HR, 3.32; 1.34-8.19; P = .009) remained significant predictors of AF. At 12 months, patients with CHF and/or LAE (40 of 142 patients) had an AF detection rate of 23.4% vs 5.0% for patients with neither (HR, 5.1; 95% CI, 2.0-12.8; P < .001).

Conclusions and Relevance

Among patients with ischemic stroke attributed to large- or small-vessel disease, CHF and LAE were associated with a significantly increased risk of poststroke AF detection. These patients may benefit most from the use of ICMs as part of a secondary stroke prevention strategy. However, the study was not powered for clinical predictors of AF, and therefore, other clinical characteristics may not have reached statistical significance.

Trial Registration

ClinicalTrials.gov Identifier: NCT02700945.

Utility of a smartphone application in assessing palmar circulation prior to radial artery harvesting for coronary artery bypass grafting: rationale and design of the randomised CAPITAL iRADIAL-CABG trial

INTRODUCTION

There is emerging evidence supporting the use of the radial artery (RA) as a preferred secondary conduit for coronary artery bypass grafting (CABG) as it is associated with higher rates of graft patency at 5 years when compared with saphenous vein grafts (SVG). The modified Allen's test (MAT) is traditionally regarded as the standard of care in the assessment of ulnar artery (UA) patency prior to RA harvesting. Unfortunately, due to high false-positive rates, a substantial number of pre-CABG patients are found to have an abnormal MAT despite normal UA patency, resulting in inappropriate exclusion from RA harvesting. The SVG is generally used in its place when this occurs, resulting in potentially lower rates of long-term graft patency.

METHODS AND ANALYSIS

The CAPITAL iRADIAL-CABG trial is currently enrolling participants 18 years of age or older undergoing CABG for whom the treating physician is considering the use of an RA conduit. Eligible patients will be randomised in a 1:1 fashion to MAT or smartphone-based photoplethysmography application assessment to assess collateral palmar circulation prior to RA harvesting. The primary outcome of the trial is the use of the RA as a conduit during CABG. The primary safety outcome is postoperative palmar ischaemia as determined by clinical assessment or requirement of vascular intervention. Secondary outcomes include vascular complications, early graft failure, need for rescue percutaneous coronary intervention during the index hospitalisation and a composite cardiovascular outcome of myocardial infarction, stroke and cardiovascular death prior to discharge from hospital. A total of 236 participants are planned to be recruited.

ETHICS AND DISSEMINATION

The study was approved by the Ottawa Heart Science Network Research Ethics Board (approval number 20180865-01H). The study results will be disseminated via conference presentations and peer-reviewed publications.

TRIAL REGISTRATION NUMBER

NCT03810729.

Post-coronavirus disease 2019 polyneuropathy with significant response to immunoglobulin therapy: a case report

Background

The symptoms of coronavirus disease 2019, caused by the novel severe acute respiratory syndrome coronavirus 2, were originally assumed to be mainly respiratory. With increasing knowledge, however, it turned out that the spectrum of complaints varies broadly with age and concomitant diseases. While many neurological symptoms were reported in the context of the disease, ranging from permanent fatigue to recurrent headaches and concentration disturbance, treatment approaches are still in development. This case discusses a possible treatment approach with immunoglobulin therapy and its outcomes.

Case presentation

We present the case of a 56-year-old Caucasian female patient who, following coronavirus disease 2019, developed peripheral sensory and autonomic disturbances that fell within subacute demyelinating neuropathy. Because a significant improvement in symptoms as well as in the results of clinical and electrophysiological examination was reported after immunoglobulin therapy, long-term therapy does not appear to be necessary.

Conclusion

Given the significant subjective and objective improvement reported, this case provides additional evidence that immunoglobulin therapy can be considered in post-coronavirus disease 2019 syndrome.

Tubulin-folding cofactor E deficiency is associated with vascular dysfunction and endoplasmatic reticulum stress of vascular smooth muscle cells

Introduction

Endothelial function assessed via flow mediated dilatation (FMD) has shown to predict risk in individuals with established cardiovascular diseases, whereas its predictive value is uncertain in the setting primary prevention.

Purpose

The aim of the current work was to discover and evaluate novel mediators of vascular dysfunction in the general population and in conditional knock-out transgenic animal models.

Methods

In order to identify novel targets that were negatively correlated with FMD and investigate their contribution in vascular function, a Genome Wide Association Study (GWAS) of 5,000 participants was performed and subsequently immune cell-, endothelial- and vascular smooth muscle cell (VSMCs)-targeted conditional knockout mouse models were generated and characterized.

Results

GWAS analysis revealed that single nucleotide polymorphisms (SNPs) in the tubulin folding cofactor E (TBCE) gene were negatively correlated with FMD and TBCE expression in the peripheral blood mononuclear cells (PBMCs). Myelomonocytic cell-targeted TBCE deficiency did not lead to any vascular dysfunction in vivo in the LysM+Cre+/−TBCEfl/fl mice. Endothelial-targeted TBCE deficiency led to an NLR family pyrin domain containing 3 (NLRP3)-dependent activation of the inflammasome in the endothelial cells of Tie2-ERT2Cre+/−TBCEfl/fl mice. Importantly, VSMC-targeted TBCE deficiency was associated with endothelial dysfunction, increased aortic wall thickness and endoplasmatic reticulum (ER) stress-mediated VSMC hyperproliferation in vivo (SMMHC-ERT2Cre+/−TBCEfl/fl), paralleled by calnexin upregulation. Administration of the blood pressure hormone angiotensin II exacerbated the vascular dysfunction and phenotype. Administration of the ER stress modulator tauroursodeoxycholic acid to the SMMHC-ERT2Cre+/−TBCEfl/fl mice reversed vascular dysfunction, paralleled by induction of Raptor/Beclin-1-dependent autophagy both in vitro and in vivo.

Conclusion

TBCE and tubulin homeostasis in the vascular musculature seem to be novel markers of vascular function and represent a new druggable target for the treatment of ER-stress-mediated vascular dysfunction.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): This work was supported by grants of the German Federal Ministry for Education and Research (BMBF01EO1003 and BMBF01EO1503), the DFG Major Research Instrumentation Programme (DFG INST 371/47-1 FUGG) as well as the Boehringer Ingelheim Foundation. PW received funds from the German Research Foundation in support of his work (DFG WE4361-4-1 and WE 4361/7-1). KS, TM and PW are PIs of the DZHK.

Comparing 2 Years of Empowering Families to Solve Real-World Problems with AI

Over the course of 2 years a global technology education nonprofit engaged ~ 20,000 under-resourced 3rd-8th grade students, parents and educators from 13 countries in a multi-week AI competition. Families worked together with the help of educators to identify meaningful problems in their communities and developed AI-prototypes to address them. Key findings included: (1) Identifying a high level of interest in underserved communities to develop and apply AI-literacy skills; (2) Determining curricular and program implementation elements that enable families to apply AI knowledge and skills to real problems; (3) Identifying effective methods of engaging industry mentors to support participants; (4) Measuring and identifying changes in self-efficacy and ability to apply AI-based tools to real-world problems; (5) Determining effective curricula around value-sensitive design and ethical innovation.

Channel-hopping during surface electrical neurostimulation elicits selective, comfortable, distally referred sensations

Objective.Lack of sensation from a hand or prosthesis can result in substantial functional deficits. Surface electrical stimulation of the peripheral nerves is a promising non-invasive approach to restore lost sensory function. However, the utility of standard surface stimulation methods has been hampered by localized discomfort caused by unintended activation of afferents near the electrodes and limited ability to specifically target underlying neural tissue. The objectives of this work were to develop and evaluate a novel channel-hopping interleaved pulse scheduling (CHIPS) strategy for surface stimulation that is designed to activate deep nerves while reducing activation of fibers near the electrodes.Approach.The median nerve of able-bodied subjects was activated by up to two surface stimulating electrode pairs placed around their right wrist. Subjects received biphasic current pulses either from one electrode pair at a time (single-channel), or interleaved between two electrode pairs (multi-channel). Percept thresholds were characterized for five pulse durations under each approach, and psychophysical questionnaires were used to interrogate the perceived modality, quality and location of evoked sensations.Main results.Stimulation with CHIPS elicited enhanced tactile percepts that were distally referred, while avoiding the distracting sensations and discomfort associated with localized charge densities. These effects were reduced after introduction of large delays between interleaved pulses.Significance.These findings demonstrate that our pulse scheduling strategy can selectively elicit referred sensations that are comfortable, thus overcoming the primary limitations of standard surface stimulation methods. Implementation of this strategy with an array of spatially distributed electrodes may allow for rapid and effective stimulation fitting. The ability to elicit comfortable and referred tactile percepts may enable the use of this neurostimulation strategy to provide meaningful and intuitive feedback from a prosthesis, enhance tactile feedback after sensory loss secondary to nerve damage, and deliver non-invasive stimulation therapies to treat various pain conditions.

RIPK1 Expression Associates With Inflammation in Early Atherosclerosis in Humans and Can Be Therapeutically Silenced to Reduce NF-κB Activation and Atherogenesis in Mice

BACKGROUND

Chronic activation of the innate immune system drives inflammation and contributes directly to atherosclerosis. We previously showed that macrophages in the atherogenic plaque undergo RIPK3 (receptor-interacting serine/threonine-protein kinase 3)-MLKL (mixed lineage kinase domain-like protein)-dependent programmed necroptosis in response to sterile ligands such as oxidized low-density lipoprotein and damage-associated molecular patterns and that necroptosis is active in advanced atherosclerotic plaques. Upstream of the RIPK3-MLKL necroptotic machinery lies RIPK1 (receptor-interacting serine/threonine-protein kinase 1), which acts as a master switch that controls whether the cell undergoes NF-κB (nuclear factor κ-light-chain-enhancer of activated B cells)-dependent inflammation, caspase-dependent apoptosis, or necroptosis in response to extracellular stimuli. We therefore set out to investigate the role of RIPK1 in the development of atherosclerosis, which is driven largely by NF-κB-dependent inflammation at early stages. We hypothesize that, unlike RIPK3 and MLKL, RIPK1 primarily drives NF-κB-dependent inflammation in early atherogenic lesions, and knocking down RIPK1 will reduce inflammatory cell activation and protect against the progression of atherosclerosis.

METHODS

We examined expression of RIPK1 protein and mRNA in both human and mouse atherosclerotic lesions, and used loss-of-function approaches in vitro in macrophages and endothelial cells to measure inflammatory responses. We administered weekly injections of RIPK1 antisense oligonucleotides to Apoe^-/- mice fed a cholesterol-rich (Western) diet for 8 weeks.

RESULTS

We find that RIPK1 expression is abundant in early-stage atherosclerotic lesions in both humans and mice. Treatment with RIPK1 antisense oligonucleotides led to a reduction in aortic sinus and en face lesion areas (47.2% or 58.8% decrease relative to control, P<0.01) and plasma inflammatory cytokines (IL-1α [interleukin 1α], IL-17A [interleukin 17A], P<0.05) in comparison with controls. RIPK1 knockdown in macrophages decreased inflammatory genes (NF-κB, TNFα [tumor necrosis factor α], IL-1α) and in vivo lipopolysaccharide- and atherogenic diet-induced NF-κB activation. In endothelial cells, knockdown of RIPK1 prevented NF-κB translocation to the nucleus in response to TNFα, where accordingly there was a reduction in gene expression of IL1B, E-selectin, and monocyte attachment.

CONCLUSIONS

We identify RIPK1 as a central driver of inflammation in atherosclerosis by its ability to activate the NF-κB pathway and promote inflammatory cytokine release. Given the high levels of RIPK1 expression in human atherosclerotic lesions, our study suggests RIPK1 as a future therapeutic target to reduce residual inflammation in patients at high risk of coronary artery disease.

Abstract 125: Capital Do-Re-Mi: A Randomized Trial of Dobutamine Compared to Milrinone in Cardiogenic Shock

Introduction: Cardiogenic shock (CS) is associated with significant morbidity and mortality. Although inotropic support is a mainstay of medical therapy for CS, little evidence exists to guide the selection of inotropic agents in clinical practice.

Methods: In this double blind randomized controlled trial, we assigned patients with SCAI class B to E shock to either milrinone or dobutamine for inotropic support. Therapy was titrated based on clinical, biochemical and hemodynamic response as evaluated by the treating physician. The primary outcome was a combined endpoint of in hospital mortality, non-fatal MI, stroke, new initiation of renal replacement therapy (RRT), need for MCS or cardiac transplant, or cardiac arrest with successful resuscitation. Secondary outcomes included individual components of the primary outcome.

Results: Among 192 participants, there was no significant difference in the primary outcome, occurring in 49% (47 of 96) of patients in the milrinone arm and 54% (52 of 96) patients in the dobutamine group (RR 0.90, 95% CI of 0.69-1.19, p-value = 0.47). There were also no differences in important secondary outcomes between milrinone and dobutamine, including in-hospital mortality 37% (35 of 96) vs 43% (41 of 96) (RR 0.85, 95% CI 0.60-1.21, p-value = 0.38) or need for RRT 22% (21 of 96) vs 17% (16 of 96) (RR 1.31, 95% CI 0.73-2.36, p-value = 0.36).

Conclusions: In this randomized clinical trial of milrinone and dobutamine in CS, there was no difference in the primary composite outcome or in important secondary outcomes. The selection of inotropic agent could reasonably be based on physician comfort, cost and individual response to therapy.

A Shifting Paradigm: The Role of Focused Cardiac Ultrasound in Bedside Patient Assessment

Transthoracic echocardiography is the standard of care in anatomic and functional cardiovascular assessment; however, focused cardiac ultrasound (FoCUS) performed with portable ultrasound equipment is increasingly being used as an adjunct to comprehensive history and physical examination. FoCUS assessments, unlike formal echocardiography, are intended to assist physicians in answering explicit clinical questions with a narrow differential diagnosis in real time. Over the past decade, a growing body of literature has repeatedly shown the value that FoCUS adds to clinical evaluation. Specifically, FoCUS improves point-of-care diagnostic accuracy, which in turn modifies treatment plans, decreases time to diagnosis, and reduces resource utilization. Although less robust, there is also evidence showing improvement in clinical outcomes. Based on this evidence, clinicians, training programs, and clinical societies have embraced FoCUS as a tool to complement bedside patient evaluation. Herein, we review the evidence for FoCUS in clinical practice, specifically evaluating the diagnostic accuracy, the impact on clinical decision-making, and the effect on clinical outcomes.

Intra-Arterial Verapamil Treatment in Oral Therapy-Refractory Reversible Cerebral Vasoconstriction Syndrome

Reversible vasoconstriction syndrome is a complex of clinical symptoms and angiographic findings, which, while having a mostly benign clinical course, has clinical and imaging overlap with more serious disorders such as vasculitis and aneurysmal SAH and itself includes a minority of patients with fulminant vasoconstriction resulting in severe intracranial complications. Endovascular options for patients with refractory reversible cerebral vasoconstriction syndrome include intra-arterial vasodilator infusion similar to therapy for patients with vasospasm after SAH. To date, only case reports and 1 small series have discussed the utility of intra-arterial vasodilators for the treatment of reversible cerebral vasoconstriction syndrome. We report an additional series of 11 medically refractory cases of presumed or proved reversible cerebral vasoconstriction syndrome successfully treated with intra-arterial verapamil infusion. Furthermore, we propose that the reversal of vasoconstriction, as seen on angiography, could fulfill a diagnostic criterion.

Comparative Accuracy of Focused Cardiac Ultrasonography and Clinical Examination for Left Ventricular Dysfunction and Valvular Heart Disease: A Systematic Review and Meta-analysis

BACKGROUND

Incorporating focused cardiac ultrasonography (FoCUS) into clinical examination could improve the diagnostic yield of bedside patient evaluation.

PURPOSE

To compare the accuracy of FoCUS-assisted clinical assessment versus clinical assessment alone for diagnosing left ventricular dysfunction or valvular disease in adults having cardiovascular evaluation.

DATA SOURCES

English-language searches of MEDLINE, Embase, and Web of Science from 1 January 1990 to 23 May 2019 and review of reference citations.

STUDY SELECTION

Eligible studies were done in patients having cardiovascular evaluation; compared FoCUS-assisted clinical assessment versus clinical assessment alone for the diagnosis of left ventricular systolic dysfunction, aortic or mitral valve disease, or pericardial effusion; and used transthoracic echocardiography as the reference standard.

DATA EXTRACTION

Three study investigators independently abstracted data and assessed study quality.

DATA SYNTHESIS

Nine studies were included in the meta-analysis. The sensitivity of clinical assessment for diagnosing left ventricular dysfunction (left ventricular ejection fraction <50%) was 43% (95% CI, 33% to 54%), whereas that of FoCUS-assisted examination was 84% (CI, 74% to 91%). The specificity of clinical assessment was 81% (CI, 65% to 90%), and that of FoCUS-assisted examination was 89% (CI, 85% to 91%). The sensitivities of clinical assessment and FoCUS-assisted examination for diagnosing aortic or mitral valve disease (of at least moderate severity) were 46% (CI, 35% to 58%) and 71% (CI, 63% to 79%), respectively. Both the clinical assessment and the FoCUS-assisted examination had a specificity of 94% (CI, 91% to 96%).

LIMITATION

Evidence was scant, persons doing ultrasonography had variable skill levels, and most studies had unclear or high risk of bias.

CONCLUSION

Clinical examination assisted by FoCUS has greater sensitivity, but not greater specificity, than clinical assessment alone for identifying left ventricular dysfunction and aortic or mitral valve disease; FoCUS-assisted examination may help rule out cardiovascular pathology in some patients, but it may not be sufficient for definitive confirmation of cardiovascular disease suspected on physical examination.

PRIMARY FUNDING SOURCE

None. (PROSPERO: CRD42019124318).

Evaluation of Plasma Adenosine as a Marker of Cardiovascular Risk: Analytical and Biological Considerations

Background

Adenosine is a ubiquitous regulatory molecule known to modulate signaling in many cells and processes vital to vascular homeostasis. While studies of adenosine receptors have dominated research in the field, quantification of adenosine systemically and locally remains limited owing largely to technical restrictions. Given the potential clinical implications of adenosine biology, there is a need for adequately powered studies examining the role of plasma adenosine in vascular health. We sought to describe the analytical and biological factors that affect quantification of adenosine in humans in a large, real‐world cohort of patients undergoing evaluation for coronary artery disease.

Methods and Results

Between November 2016 and April 2018, we assessed 1141 patients undergoing angiography for evaluation of coronary artery disease. High‐performance liquid chromatography was used for quantification of plasma adenosine concentration, yielding an analytical coefficient of variance (CV_a) of 3.2%, intra‐subject variance (CV_i) 35.8% and inter‐subject variance (CV_g) 56.7%. Traditional cardiovascular risk factors, medications, and clinical presentation had no significant impact on adenosine levels. Conversely, increasing age (P=0.027) and the presence of obstructive coronary artery disease (P=0.026) were associated with lower adenosine levels. Adjusted multivariable analysis supported only age being inversely associated with adenosine levels (P=0.039).

Conclusions

Plasma adenosine is not significantly impacted by traditional cardiovascular risk factors; however, advancing age and presence of obstructive coronary artery disease may be associated with lower adenosine levels. The degree of intra‐ and inter‐subject variance of adenosine has important implications for biomarker use as a prognosticator of cardiovascular outcomes and as an end point in clinical studies.

Adenosine as a Marker and Mediator of Cardiovascular Homeostasis: A Translational Perspective

Adenosine, a purine nucleoside, is produced broadly and implicated in the homeostasis of many cells and tissues. It signals predominantly via 4 purinergic adenosine receptors (ADORs) - ADORA1, ADORA2A, ADORA2B and ADOosine signaling, both through design as specific ADOR agonists and antagonists and as offtarget effects of existing anti-platelet medications. Despite this, adenosine has yet to be firmly established as either a therapeutic or a prognostic tool in clinical medicine to date. Herein, we provide a bench-to-bedside review of adenosine biology, highlighting the key considerations for further translational development of this proRA3 in addition to non-ADOR mediated effects. Through these signaling mechanisms, adenosine exerts effects on numerous cell types crucial to maintaining vascular homeostasis, especially following vascular injury. Both in vitro and in vivo models have provided considerable insights into adenosine signaling and identified targets for therapeutic intervention. Numerous pharmacologic agents have been developed that modulate adenmising molecule.

Specificity of late-night salivary cortisol measured by automated electrochemiluminescence immunoassay for Cushing's disease in an obese population

PURPOSE

Data about the specificity of late-night salivary cortisol (LNSC) in obese subjects are still conflicting. Therefore, with this study, we aimed to evaluate the specificity of LNSC measurement in an obese cohort with or without type 2 diabetes mellitus (T2DM) using an automated electrochemiluminescence immunoassay (ECLIA).

METHODS

A total number of 157 patients involving 40 healthy subjects (HS) with BMI < 25 kg/m², 83 obese subjects (OS) with BMI ≥ 35 kg/m², and 34 histopathologically proven Cushing's disease (CD) were included. All patients underwent LNSC testing. Salivary cortisol was measured at 11 p.m. for all groups using an ECLIA. Reference range was established using values of LNSCs of HS and ROC curves were used to determine diagnostic cutoffs.

RESULTS

In the HS group, mean LNSC was 4.7 nmol/l (SD ± 3.1), while the OS group had a mean value of 10.9 nmol/l (SD ± 7.5) and the CD group of 19.9 nmol/l (SD ± 15.4). All groups differed significantly (p < 0.001). The ROC analysis of CD against HS alone showed a sensitivity of 85.3% and a specificity of 87.5% with a cut-off value of 8.3 nmol/l. The ROC analysis between OS and CD showed a maximum sensitivity of 67.6% and specificity of 78.3% for a cut-off value of 12.3 nmol/l. Taken both (HS and OS) groups together against the CD group, ROC analysis showed a maximum sensitivity of 67.6% and specificity of 85.4% for a cut-off value of 12.3 nmol/l. No correlation was found between BMI, T2DM, and LNSC for all groups.

CONCLUSIONS

In our obese cohort, we found that LNSC assayed by ECLIA had a low specificity in the diagnosis of CD.

Adaptive changes in pancreas post Roux-en-Y gastric bypass induced weight loss

BACKGROUND

Obesity has been shown to trigger adaptive increases in pancreas parenchymal and fat volume. Consecutively, pancreatic steatosis may lead to beta-cell dysfunction. However, it is not known whether the pancreatic tissue components decrease with weight loss and pancreatic steatosis is reversible following Roux-en-Y gastric bypass (RYGB). Therefore, the objective of the study was to investigate the effects of RYGB-induced weight loss on pancreatic volume and glucose homeostasis.

METHODS

Eleven patients were recruited in the Obesity Centre of the University Medical Centre Hamburg-Eppendorf. Before and 6 months after RYGB, total GLP-1 levels were measured during oral glucose tolerance test. To assess changes in visceral adipose tissue and pancreatic volume, MRI was performed. Measures of glucose homeostasis and insulin indices were assessed. Fractional beta-cell area was estimated by correlation with the C-peptide-to-glucose ratio; beta-cell mass was calculated by the product of beta-cell area and pancreas parenchymal weight.

RESULTS

Pancreas volume decreased from 83.8 (75.7-92.0) to 70.5 (58.8-82.3) cm³ (mean [95% CI], P = .001). The decrease in total volume was associated with a significant decrease in fat volume. Fasting insulin and C-peptide were lower post RYGB. HOMA-IR levels decreased, whereas insulin sensitivity increased (P = .03). This was consistent with a reduction in the estimated beta-cell area and mass.

CONCLUSIONS

Following RYGB, pancreatic volume and steatosis adaptively decreased to "normal" levels with accompanying improvement in glucose homeostasis. Moreover, obesity-driven beta-cell expansion seems to be reversible; however, future studies must define a method to more accurately estimate functional beta-cell mass to increase our understanding of glucose homeostasis after RYGB.

Mechanical fatigue resistance of an implantable branched lead system for a distributed set of longitudinal intrafascicular electrodes

OBJECTIVE

A neural interface system has been developed that consists of an implantable stimulator/recorder can with a 15-electrode lead that trifurcates into three bundles of five individual wire longitudinal intrafascicular electrodes. This work evaluated the mechanical fatigue resistance of the branched lead and distributed electrode system under conditions designed to mimic anticipated strain profiles that would be observed after implantation in the human upper arm.

APPROACH

Custom test setups and procedures were developed to apply linear or angular strain at four critical stress riser points on the lead and electrode system. Each test was performed to evaluate fatigue under a high repetition/low amplitude paradigm designed to test the effects of arm movement on the leads during activities such as walking, or under a low repetition/high amplitude paradigm designed to test the effects of more strenuous upper arm activities. The tests were performed on representative samples of the implantable lead system for human use. The specimens were fabricated using procedures equivalent to those that will be used during production of human-use implants. Electrical and visual inspections of all test specimens were performed before and after the testing procedures to assess lead integrity.

MAIN RESULTS

Measurements obtained before and after applying repetitive strain indicated that all test specimens retained electrical continuity and that electrical impedance remained well below pre-specified thresholds for detection of breakage. Visual inspection under a microscope at 10×  magnification did not reveal any signs of damage to the wires or silicone sheathing at the stress riser points.

SIGNIFICANCE

These results demonstrate that the branched lead of this implantable neural interface system has sufficient mechanical fatigue resistance to withstand strain profiles anticipated when the system is implanted in an arm. The novel test setups and paradigms may be useful in testing other lead systems.

Application of low-frequency sonophoresis and reduction of antibiotics in the aquatic systems

A major concern in aquaculture is the use of chemical therapeutics, such as antibiotics, because of their impact on the environment as well as on the fish product. As a potential tool for reducing antibiotic use, we tested the application of low-frequency ultrasound as a method for enhancing antibiotic uptake. Rainbow trout juveniles (Oncorhynchus mykiss) were exposed to two different concentrations of oxytetracycline (OTC), flumequine (FLU) and florfenicol (FLO), administered by bath after the application of ultrasound. After exposure, concentrations of these substances were measured in the liver and blood of treated fish. Results showed that the ultrasound treatment can significantly increase the uptake for all three antibiotics. The uptake of OTC for example, in fish exposed to an OTC concentration of 20 mg L^-1 after prior treatment with ultrasound, was similar to the OTC concentrations in their liver and blood to fish exposed to 100 mg L^-1 without sonication. For FLU and FLO, the use of ultrasound caused significant differences of uptake in the liver at high antibiotic concentrations. This suggests that the use of ultrasound as a technique to deliver antibiotics to fish can ultimately reduce the amount of antibiotics discharged into the aquatic environment.

Transverse Coherence Limited Coherent Diffraction Imaging using a Molybdenum Soft X-ray Laser Pumped at Moderate Pump Energies

Coherent diffraction imaging (CDI) in the extreme ultraviolet has become an important tool for nanoscale investigations. Laser-driven high harmonic generation (HHG) sources allow for lab scale applications such as cancer cell classification and phase-resolved surface studies. HHG sources exhibit excellent coherence but limited photon flux due poor conversion efficiency. In contrast, table-top soft X-ray lasers (SXRL) feature excellent temporal coherence and extraordinary high flux at limited transverse coherence. Here, the performance of a SXRL pumped at moderate pump energies is evaluated for CDI and compared to a HHG source. For CDI, a lower bound for the required mutual coherence factor of |μ₁₂| ≥ 0.75 is found by comparing a reconstruction with fixed support to a conventional characterization using double slits. A comparison of the captured diffraction signals suggests that SXRLs have the potential for imaging micron scale objects with sub-20 nm resolution in orders of magnitude shorter integration time compared to a conventional HHG source. Here, the low transverse coherence diameter limits the resolution to approximately 180 nm. The extraordinary high photon flux per laser shot, scalability towards higher repetition rate and capability of seeding with a high harmonic source opens a route for higher performance nanoscale imaging systems based on SXRLs.

Sensor-controlled scalp cooling to prevent chemotherapy-induced alopecia in female cancer patients

BACKGROUND

Scalp cooling has been used since the 1970s to prevent chemotherapy-induced alopecia, one of the most common and psychologically troubling side effects of chemotherapy. Currently available scalp cooling systems demonstrate varying results in terms of effectiveness and tolerability.

METHODS

For the present prospective study, 55 women receiving neoadjuvant, adjuvant, or palliative chemotherapy were enrolled. The aim was to assess the effectiveness of a sensor-controlled scalp cooling system (DigniCap: Sysmex Europe GmbH, Norderstedt, Germany) to prevent chemotherapy-induced alopecia in breast or gynecologic cancer patients receiving 1 of 7 regimens. Clinical assessments, satisfaction questionnaires, and alopecia evaluations [World Health Organization (who) grading for toxicity] were completed at baseline, at each cycle, and at completion of chemotherapy.

RESULTS

Of the 55 patients, 78% underwent scalp cooling until completion of chemotherapy. In multivariate analysis, younger women and those receiving paclitaxel weekly or paclitaxel-carboplatin experienced less alopecia. The compound successful outcome ("no head covering" plus "who grade 0/1") was observed in all patients 50 years of age and younger receiving 4 cycles of docetaxel-cyclophosphamide or 6 cycles of paclitaxel-carboplatin. Conversely, alopecia was experienced by all women receiving triplet polychemotherapy (6 cycles of docetaxel-doxorubicin-cyclophosphamide). For women receiving sequential polychemotherapy regimens (3 cycles of fluorouracil-epirubicin-cyclophosphamide followed by 3 cycles of docetaxel or 4 cycles of doxorubicin-cyclophosphamide followed by 4 cycles of docetaxel), the subgroup 50 years of age and younger experienced a 43% success rate compared with a 10% rate for the subgroup pf older women receiving the same regimens.

CONCLUSIONS

The ability of scalp cooling to prevent chemotherapy-induced alopecia varies with the chemotherapy regimen and the age of the patient. Use of a compound endpoint with subjective and objective measures provides insightful and practical information when counselling patients.

Contact system revisited: an interface between inflammation, coagulation, and innate immunity

The contact system is a plasma protease cascade initiated by factor XII (FXII) that activates the proinflammatory kallikrein-kinin system and the procoagulant intrinsic coagulation pathway. Anionic surfaces induce FXII zymogen activation to form proteolytically active FXIIa. Bacterial surfaces also have the ability to activate contact system proteins, indicating an important role for host defense using the cooperation of the inflammatory and coagulation pathways. Recent research has shown that inorganic polyphosphate found in platelets activates FXII in vivo and can induce coagulation in pathological thrombus formation. Experimental studies have shown that interference with FXII provides thromboprotection without a therapy-associated increase in bleeding, renewing interest in the FXIIa-driven intrinsic pathway of coagulation as a therapeutic target. This review summarizes how the contact system acts as the cross-road of inflammation, coagulation, and innate immunity.

Effects of Adenovirus Type 5 E1A Isoforms on Viral Replication in Arrested Human Cells

Human adenovirus has evolved to infect and replicate in terminally differentiated human epithelial cells, predominantly those within the airway, the gut, or the eye. To overcome the block to viral DNA replication present in these cells, the virus expresses the Early 1A proteins (E1A). These immediate early proteins drive cells into S-phase and induce expression of all other viral early genes. During infection, several E1A isoforms are expressed with proteins of 289, 243, 217, 171, and 55 residues being present for human adenovirus type 5. Here we examine the contribution that the two largest E1A isoforms make to the viral life cycle in growth-arrested normal human fibroblasts. Viruses that express E1A289R were found to replicate better than those that do not express this isoform. Importantly, induction of several viral genes was delayed in a virus expressing E1A243R, with several viral structural proteins undetectable by western blot. We also highlight the changes in E1A isoforms detected during the course of viral infection. Furthermore, we show that viral DNA replication occurs more efficiently, leading to higher number of viral genomes in cells infected with viruses that express E1A289R. Finally, induction of S-phase specific genes differs between viruses expressing different E1A isoforms, with those having E1A289R leading to, generally, earlier activation of these genes. Overall, we provide an overview of adenovirus replication using modern molecular biology approaches and further insights into the contribution that E1A isoforms make to the life cycle of human adenovirus in arrested human fibroblasts.

TK inhibitor treatment disrupts growth hormone axis: clinical observations in children with CML and experimental data from a juvenile animal model

BACKGROUND

Long-term treatment of chronic myeloid leukemia (CML) with tyrosine kinase inhibitors (TKIs) exerts off-target effects on bone growth by either impaired growth hormone (GH) action or osseous modelling impairment.

METHODS

Body height and the GH-related parameters insulin-like growth factor 1 (IGF-1) and insulin-like growth factor-binding protein 3(IGFBP-3) were determined repetitively 3-monthly over 2 years in 21 pediatric CML-patients on standardized imatinib treatment. In an animal model 4-week-old male Wistar rats were exposed over 10 weeks to imatinib, dasatinib, or bosutinib at varying concentrations via the drinking water. Blood was collected at prepubertal age, pubertal age, and at adult age, respectively, and animals' serum levels of IGFBP-3 were measured.

RESULTS

Independent from treatment duration patients exhibited IGF-1 and IGFBP-3 levels almost exclusively in the very low range when compared to age-matched references. No clear pattern of rising or falling IGF-1 and IGFBP-3 levels was observed. In rats, compared to controls, serum IGFBP-3 was significantly lowered for all TKIs tested, at all concentrations applied, and at all ages under investigation.

CONCLUSION

Besides direct off-target effects on the growing skeleton, TKI treatment also results in lowered blood levels of IGF-1 and IGFBP-3.A juvenile rat model predicts this side effect for dasatinib and bosutinib. Thus, growth and GH- related parameters should be monitored regularly in pediatric patients with CML on TKIs.