Signs of chronic thromboembolic pulmonary hypertension in acute pulmonary embolism: results from the FOCUS study

Background/Introduction

Chronic thromboembolic pulmonary hypertension (CTEPH) is considered to be a late complication of acute pulmonary embolism (PE). However, up to one third of CTEPH patients do not report prior symptomatic venous thromboembolism (VTE). Furthermore, a substantial proportion of patients presenting with an acute PE event may exhibit radiological signs of chronicity at baseline computed tomography pulmonary angiography (CTPA).

Purpose

To determine the prevalence of baseline radiological parameters indicating chronic thrombosis or pulmonary hypertension, and ultimately pre-existing CTEPH, among patients with acute PE enrolled in the prospective multicentre Follow-Up after Acute Pulmonary Embolism (FOCUS) cohort study.

Methods

Patients with acute symptomatic PE and absence of a known history of CTEPH, enrolled at two large FOCUS centres, were included. The assessment of index CTPA scans was conducted by two independent expert radiologists who were unaware of the clinical characteristics and the follow-up data of the patients. CTPA parameters indicating chronicity were prespecified on the basis of recently proposed criteria in the literature. A third independent expert radiologist provided an assessment in case of disagreement between the first two. Baseline radiological data were prospectively validated with the aid of two-year prospective clinical follow-up data focusing on CTEPH and the post-PE syndrome (co-primary outcomes of the FOCUS study).

Results

A total of 303 patients (median age: 63 years, 44.6% women) were included. In >95% of the patients, the expert radiologists could confirm signs of acute PE at baseline CTPA. Radiological signs of chronic thrombi or pulmonary hypertension at baseline were detected in 46 (15.2%) patients. In 8 patients, the expert radiologists agreed on the presence of pre-existing CTEPH based on their interpretation of the overall radiological pattern. During follow-up, five (1.7%; 95% CI 0.7–3.8%) of 303 patients were diagnosed with CTEPH, over a median time of 95 days after baseline. Four of them were among the 8 patients in whom the radiological experts suspected pre-existing CTEPH at baseline, and among the 46 patients in whom CTPA findings suggesting chronic thrombi or chronic pulmonary hypertension were present at baseline. The use of the predefined individual parameters of chronicity from the literature also helped identifying patients with chronic disease, and could be used as a tool for screening acute PE patients for pre-existing CTEPH.

Conclusion

A substantial proportion of patients who are diagnosed with CTEPH during follow-up after acute PE may already have pre-existing CTEPH at the time of the index event. An intensified follow-up programme and focussed screening for CTEPH should be considered in patients with signs of chronicity at baseline CTPA.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Bayer Health Care

P–280 Changes in oolemma height during ICSI injection on day 0 is associated with day 5–6 blastocyst formation

Study question

Does the oolemma response to ICSI injection on day 0 affect blastocyst formation on day 5–6 (d5/6)?

Summary answer

A large change in oolemma height during ICSI injection on day 0 is associated with lower blastocyst formation rates on d5/6.

What is known already

The oolemma changes in all dimensions (i.e. height, width and depth) and can exhibit different reactions in ICSI during needle injection. This is seen as instant rupture or with little needle pressure, normal rupture with the needle pushed approximately halfway through, or difficult rupture with repeated attempts or the needle passing 3/4 of the oocyte width. Previous studies have shown that these responses can affect degeneration and fertilisation rates on day 1, however, there is little research on its effect on blastocyst formation rates. Furthermore, most previous studies have used qualitative methods to assess oolemma response.

Study design, size, duration

This is a retrospective study using ICSI procedure videos conducted by four embryologists in a private clinic from 2013–2015. All videos of procedures which did not result in 2PN or in which the oocyte was not fully visible were excluded. Six operators categorised 455 videos (by majority vote) into four groups based on the oolemma response: oolemma breakage within 1/4, between 1/4 and 1/2, between 1/2 and 3/4 and beyond 3/4 of the oocyte’s width.

Participants/materials, setting, methods

A U-Net neural network model was trained to extract the frame of maximum oolemma indent from each video which were validated by a human operator; any in which maximum indent occured after breaking of the oolemma were excluded. The ratio of starting to maximal indent width/height were calculated automatically and human-validated. Chi-squared tests were performed for each ratio vs d5/6 blastocyst formation. These results were compared with those obtained from purely human annotations.

Main results and the role of chance

From the purely human annotations, the percentages of oocytes in groups 1–4 respectively were: 3.3%, 85.3%, 11.4% and 0%. This variation in oolemma response may be due to the arrangement of thick and thin microfilaments or cortical granules in the cytoskeleton. When analysed with d5/6 blastocyst formation, these showed no significant result (p = 0.12) which is consistent with findings using the model.

The artificial intelligence (AI) model processed 26 frames per second. During human validation of the ratios calculated at maximal indentation, 36% of width ratios and 31% of height ratios were rejected.

The proportion of blastocysts formed in the upper and lower quartile for each ratio was analysed. Both the upper (0.49) and lower (0.41) quartiles of the width ratios were not significant for d5/6 blastocyst formation. The lower (1.12) quartile of height ratios showed no significance, however there were significantly fewer blastocysts formed on d5/6 for the upper (1.18) quartile of height ratios (p < 0.025). This subtle change in the height ratio, which was significant for d5/6 blastocyst formation was not taken into account when grouping oocytes any previous literature (and our human labelling).

Limitations, reasons for caution

This study was conducted at a single clinic so variations between clinics were not captured in the study and would need further collaborations to confirm the proportion of oocytes responses. Due to the small sample size, this study also did not identify any group 4 oocytes cultured until d5/6.

Wider implications of the findings: The grouping criteria in this study were more quantitative than previous work yet indicated no correlation between the oolemma group and d5/6 blastocyst formation. However, changes in the height which are hard to assess in real-time (and which have been neglected in previous literature) were seen to be significant.

Trial registration number

NA

Can cilia provide an entry gateway for SARS-CoV-2 to human ciliated cells?

A worldwide coronavirus pandemic is in full swing and, at the time of writing, there are only few treatments that have been successful in clinical trials, but no effective antiviral treatment has been approved. Because of its lethality, it is important to understand the current strain's effects and mechanisms not only in the respiratory system but also in other affected organ systems as well. Past coronavirus outbreaks caused by SARS-CoV and MERS-CoV inflicted life-threatening acute kidney injuries (AKI) on their hosts leading to significant mortality rates, which went somewhat overlooked in the face of the severe respiratory effects. Recent evidence has emphasized renal involvement in SARS-CoV-2, stressing that kidneys are damaged in patients with COVID-19. The mechanism by which this virus inflicts AKI is still unclear, but evidence from other coronavirus strains may hold some clues. Two theories exist for the proposed mechanism of AKI: 1) the AKI is a secondary effect to reduced blood and oxygen levels causing hyperinflammation and 2) the AKI is due to cytotoxic effects. Kidneys express angiotensin-converting enzyme-2 (ACE2), the confirmed SARS-CoV-2 target receptor as well as collectrin, an ACE2 homologue that localizes to the primary cilium, an organelle historically targeted by coronaviruses. Although the available literature suggests that kidney damage is leading to higher mortality rates in patients with COVID-19, especially in those with preexisting kidney and cardiovascular diseases, the pathogenesis of COVID-19 is still being investigated. Here, we present brief literature review supporting our proposed hypothesis of a possible link between SARS-CoV-2 cellular infection and cilia.

Age alters peripheral vascular endothelial function without affecting coronary flow reserve in healthy volunteers

Background

Age is a key risk factor contributing to vascular endothelial dysfunction. Whether the impact of ageing is uniform on various vascular beds is unknown. Endothelial function is classically evaluated by the brachial flow mediated dilatation (FMD) after a brief occlusion which mainly involves nitric oxide (NO) production. However, FMD measurement, requiring highly trained technicians, has been shown to be associated with a high degree of variability. Endothelial function could be also assessed by cutaneous iontophoresis combined with Laser Doppler. By contrast to FMD, this method is easily done by nurses and shows less variability. In parallel, myocardial imaging allows measurement of coronary flow reserve (CFR) coupled with an adenosine challenge leading to both a NO release and a modulation of potassium channels.

Purpose

The aim of this study was to determine the impact of ageing on vasodilation of peripheral (cutaneous) and coronary blood vessels in healthy volunteers.

Methods

This prospective single German center study enrolled 75 healthy non-smoking normotensive volunteers, taking no medication. They were divided into three age-subgroups (n=25/group): 18–30, 50–59, and 60–70 years (women: 54, 27 and 23%, respectively). All subjects underwent clinical and laboratory evaluation.

Peripheral endothelial function, expressed in cutaneous blood flow (delta CBF), was assessed through cutaneous microcirculation dilation by the non-invasive method using Laser Doppler Speckle Contrast Imaging (LSCI, Perimed) coupled with iontophoresis to locally deliver 125 nmoles of acetylcholine (Ach). The CFR was determined by cardiac magnetic resonance (CMR) coupling with an intravenous infusion of adenosine at 140 μg/kg/min for at least 3 minutes.

Results

Age was associated with a 23% reduction of peripheral endothelial function (delta CBF, p=0.005) in the elderly group (60–70y) vs. the younger one (18–30y) (median: 56.4 vs. 73.6). By contrast, calculated CFR was unchanged (median: 4.1 vs. 4.2, p=0.38). No relationship was observed between peripheral endothelial function (delta CBF) and CFR (r=0.01, p>0.97) in healthy volunteers.

Conclusion

In healthy volunteers, ageing is associated with a progressive peripheral but not with a coronary vascular dysfunction. This suggests that the impact of age on endothelial dysfunction depends on different vascular beds. Peripheral endothelial function assessment does not predict coronary vascular function in healthy volunteers.

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Servier

Primary Cilia and Calcium Signaling Interactions

The calcium ion (Ca2+) is a diverse secondary messenger with a near-ubiquitous role in a vast array of cellular processes. Cilia are present on nearly every cell type in either a motile or non-motile form; motile cilia generate fluid flow needed for a variety of biological processes, such as left-right body patterning during development, while non-motile cilia serve as the signaling powerhouses of the cell, with vital singling receptors localized to their ciliary membranes. Much of the research currently available on Ca2+-dependent cellular actions and primary cilia are tissue-specific processes. However, basic stimuli-sensing pathways, such as mechanosensation, chemosensation, and electrical sensation (electrosensation), are complex processes entangled in many intersecting pathways; an overview of proposed functions involving cilia and Ca2+ interplay will be briefly summarized here. Next, we will focus on summarizing the evidence for their interactions in basic cellular activities, including the cell cycle, cell polarity and migration, neuronal pattering, glucose-mediated insulin secretion, biliary regulation, and bone formation. Literature investigating the role of cilia and Ca2+-dependent processes at a single-cellular level appears to be scarce, though overlapping signaling pathways imply that cilia and Ca2+ interact with each other on this level in widespread and varied ways on a perpetual basis. Vastly different cellular functions across many different cell types depend on context-specific Ca2+ and cilia interactions to trigger the correct physiological responses, and abnormalities in these interactions, whether at the tissue or the single-cell level, can result in diseases known as ciliopathies; due to their clinical relevance, pathological alterations of cilia function and Ca2+ signaling will also be briefly touched upon throughout this review.

Novelties in imaging in pulmonary fibrosis and nodules. A narrative review

In recent months two major fields of interest in pulmonary imaging have stood out: pulmonary fibrosis and pulmonary nodules. New guidelines have been released to define pulmonary fibrosis and subsequent studies have proved the value of these changes. In addition, new recommendations for classification of pulmonary nodules have been released. Radiological images are of major interest for automated and standardized analysis and so in both cases software tools using artificial intelligence were developed for visualization and quantification of the disease. These tools have been validated by human readers and demonstrated their capabilities. This review summarizes the new recommendations for classification of pulmonary fibrosis and nodules and reviews the capabilities of radiomics within these two entities.

EMERGENCE OF BEDAQUILINE RESISTANCE AFTER COMPLETION OF BEDAQUILINE-BASED DRUGRESISTANT TB TREATMENT: A CASE STUDY FROM SOUTH AFRICA

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FPGA controlled artificial vascular system

Monitoring the oxygen saturation of an unborn child is an invasive procedure, so far. Transabdominal fetal pulse oximetry is a promising method under research, used to estimate the oxygen saturation of a fetus noninvasively. Due to the nature of the method, the fetal information needs to be extracted from a mixed signal. To properly evaluate signal processing algorithms, a phantom modeling fetal and maternal blood circuits and tissue layers is necessary. This paper presents an improved hardware concept for an artificial vascular system, utilizing an FPGA based CompactRIO System from National Instruments. The experimental model to simulate the maternal and fetal blood pressure curve consists of two identical hydraulic circuits. Each of these circuits consists of a pre-pressure system and an artificial vascular system. Pulse curves are generated by proportional valves, separating these two systems. The dilation of the fetal and maternal artificial vessels in tissue substitutes is measured by transmissive and reflective photoplethysmography. The measurement results from the pressure sensors and the transmissive optical sensors are visualized to show the functionality of the pulse generating systems. The trigger frequency for the maternal valve was set to 1 per second, the fetal valve was actuated at 0.7 per second for validation. The reflective curve, capturing pulsations of the fetal and maternal circuit, was obtained with a high power LED (905 nm) as light source. The results show that the system generates pulse curves, similar to its physiological equivalent. Further, the acquired reflective optical signal is modulated by the alternating diameter of the tubes of both circuits, allowing for tests of signal processing algorithms.

Preliminary investigations of magnetic modulated nanoparticles for microwave breast cancer detection

This paper investigates the potential of magnetic modulated iron oxide nanoparticles in terms of a contrast enhancement for Ultra-wideband (UWB) breast imaging. The work is motivated by the low dielectric contrast between tumor and normal glandular/fibroconnective tissue. The influence of an external polarizing magnetic field on pure and coated magnetite nanoparticles is investigated in this contribution. Measurements were conducted using M-sequence UWB technology and an oil-gelatin phantom. It is shown that a coating, which is necessary for clinical use, results in a lower signal response, and thus leads to a lower detectability of magnetic modulated nanoparticles.

[HRCT technique with low-dose protocols for interstitial lung diseases]

CLINICAL/METHODICAL ISSUE

For optimal visualization of the lung parenchyma a dedicated computed tomography (CT) examination protocol has to be selected.

STANDARD RADIOLOGICAL METHODS

High resolution CT (HRCT) is the best technique for non-invasive evaluation of the lung parenchyma.

ACHIEVEMENTS

Given the possibility to examine the complete lungs within one breath hold, assessment of disease severity and distribution is easily possible. Various parameters have to be considered to generate optimal image quality and best possible clinical results.

PRACTICAL RECOMMENDATIONS

This review article discusses the various image acquisition parameters for HRCT as well as the issue of dose reduction.

Genetic diversity of Mycobacterium tuberculosis in Madang, Papua New Guinea

SETTING

Madang and surroundings, Papua New Guinea (PNG).

OBJECTIVE

To characterise the genetic diversity and drug susceptibility of Mycobacterium tuberculosis isolates collected in Madang and surroundings.

DESIGN

M. tuberculosis was isolated from sputum samples from active pulmonary tuberculosis cases. Drug resistance profiles were obtained by drug susceptibility testing. M. tuberculosis lineages were identified by single nucleotide polymorphisms and sub-typing was performed by spoligotyping. Spoligotyping and 24 locus mycobacterial interspersed repetitive units-variable number of tandem repeats were combined to identify clustered isolates.

RESULTS

The 173 M. tuberculosis isolates collected belonged predominantly to the Euro-American lineage (Lineage 4) and the East-Asian lineage (Lineage 2). Multidrug-resistant M. tuberculosis were observed in 5.2% of isolates. Lineage 2 M. tuberculosis, which includes the 'Beijing' genotype, was significantly associated with any drug resistance (OR 5.2, 95%CI 1.8-15.1). Cluster analyses showed 44% molecularly clustered isolates, suggesting transmission of M. tuberculosis in the community, including transmission of primary drug-resistant M. tuberculosis.

CONCLUSION

These data provide the first insight into the molecular characteristics of M. tuberculosis in the Madang area of PNG, and indicate substantial drug resistance with evidence of ongoing transmission.

The role of TRKA signaling in IL-10 production by apoptotic tumor cell-activated macrophages

Tumor-associated macrophages (TAMs) are a major supportive component within neoplasms. Mechanisms of macrophage (MΦ) attraction and differentiation to a tumor-promoting phenotype, which is characterized by pronounced interleukin (IL)-10 production, are under investigation. We report that supernatants of dying cancer cells induced substantial IL-10 release from primary human MΦs, dependent on signaling through tyrosine kinase receptor A (TRKA or neurotrophic tyrosine kinase receptor type 1 (NTRK1)). Mechanistically, sphingosine-1-phosphate (S1P) release from apoptotic cancer cells triggered src-dependent shuttling of cytosolic TRKA to the plasma membrane via S1P receptor signaling. Plasma membrane-associated TRKA, which was activated by constitutively autocrine secreted nerve growth factor, used phosphatidylinositol 3-kinase (PI3K)/AKT and p38 mitogen-activated protein kinase (MAPK) signaling to induce IL-10. Interestingly, TRKA-dependent signaling was required for cytokine production by TAMs isolated from primary murine breast cancer tissue. Besides IL-10, this pathway initiated secretion of IL-6, tumor necrosis factor-α (TNF-α) and monocyte chemotactic protein-1 (MCP-1), indicating relevance in cancer-associated inflammation. Our findings highlight a fine-tuned regulatory system including S1P-dependent TRKA trafficking for executing TAM-like cell function in vitro as well as in vivo.

Computed tomographic examination of South American sea lions (Otaria flavescens) with suspected Mycobacterium pinnipedii infection

Ten South American sea lions (Otaria flavescens) were presented for clinical evaluation and diagnosis of tuberculosis following known exposure to Mycobacterium pinnipedii. CT was used to determine whether foci of calcification in mediastinal lymph nodes, typically associated with pinniped tuberculosis, could be detected and whether CT was a useful diagnostic modality, in conjunction with other tests, for the diagnosis of tuberculosis in this species. Blood was collected from the caudal gluteal vein of each animal for serological testing using commercially available serological tests (ElephantTB STAT-PAK and DPP Vet; Chembio Diagnostic Systems) and a multiantigen print immunoassay (MAPIA), carried out at Chembio to verify the in-house kits. In four of nine animals that underwent CT scanning, lesions consistent with pinniped tuberculosis were apparent and these were confirmed at subsequent postmortem examination. The five remaining animals did not show any abnormalities on CT, with three being negative on serological tests, which were considered to be normal and potentially used as reference images for healthy sea lions. One animal could not be CT scanned due to its large size and weight (510 kg).

MRI in lung cancer: a pictorial essay

Imaging studies play a critical role in the diagnosis and staging of lung cancer. CT and 18-fluorodeoxyglucose positron emission tomography CT (PET/CT) are widely and routinely used for staging and assessment of treatment response. Many radiologists still use MRI only for the assessment of superior sulcus tumours, and in cases where invasion of the spinal cord canal is suspected. MRI can detect and stage lung cancer, and this method could be an excellent alternative to CT or PET/CT in the investigation of lung malignancies and other diseases. This pictorial essay discusses the use of MRI in the investigation of lung cancer.

Selected clinical highlights from the 2010 ERS Congress in Barcelona

This article reviews a selection of presentations at the 2010 annual meeting of the European Respiratory Society held in Barcelona, Spain, which was the largest congress ever in the field of respiratory medicine. The best abstracts from the groups of the Clinical Assembly (Clinical Problems, Rehabilitation and Chronic Care, Imaging, Interventional Pulmonology, Diffuse Parenchymal Lung Disease, and General Practice and Primary Care) are presented in the context of the current literature.

Magnetic resonance imaging findings in acute pulmonary embolism

Pulmonary embolism (PE) is the third most common acute cardiovascular disease after myocardial infarction and stroke, and results in thousands of deaths each year. Improvements in MRI accuracy are ongoing with the use of parallel imaging for angiography techniques and pulmonary perfusion. This, associated with other potential advantages of MRI (e.g. a radiation free method and better safety profile of MR contrast media), reinforces its use. The aim of this paper is to perform a pictorial review of the principal findings of MRI in acute PE. Acute PE can manifest itself as complete arterial occlusion and the affected artery may be enlarged. We report the main vascular and parenchymal signs, and an overview of current literature regarding accuracy, limitations and technical aspects is provided.

Neuroblastoma imaging

Neuroblastoma is an embryonic tumor of the sympathetic nervous system which represents one of the most common malignancies in early childhood. Its clinical and biological behavior show a remarkable heterogeneity, ranging from spontaneous regression to inexorable progression with a fatal outcome. This review summarizes the clinical risk stratification and treatment options. An extensive overview of the role of imaging during the course of the disease and typical imaging findings in all imaging modalities are demonstrated.

[Non-invasive diagnosis of pulmonary hypertension: ESC/ERS Guidelines with commentary of the Cologne Consensus Conference 2010]

The 2009 European Guidelines on Diagnosis and Treatment of Pulmonary Hypertension have been adopted for Germany. The guidelines contain detailed recommendations for the diagnosis of pulmonary hypertension. However, the practical implementation of the European Guidelines in Germany requires the consideration of several country-specific issues and already existing novel data. This requires a detailed commentary to the guidelines, and in some aspects an update y appears necessary. In June 2010, a Consensus Conference organized by the PH working groups of the German Society of Cardiology (DGK), the German Society of Respiratory Medicine (DGP) and the German Society of Pediatric Cardiology (DGPK) was held in Cologne, Germany. This conference aimed to solve practical and controversial issues surrounding the implementation of the European Guidelines in Germany. To this end, a number of working groups was initiated, one of which was specifically dedicated to non-invasive diagnosis of PH. This commentary summarizes the results and recommendations of the working group on treatment of PAH.

Brugada Syndrome and Brugada ECG Pattern: Unusual Causes of ST Elevation

Brugada Syndrome is a channelopathy that leads to ST elevation or right bundle branch block pattern in the right ventricular leads on ECG analysis and predisposes to ventricular tachyarrhythmias and sudden death. The ECG pattern can also be drug induced with several agents. This case describes a patient who presented after a mixed overdose of amitriptyline, olanzapine and alimemazine with ST elevation and T wave inversion on his ECG that were initially thought to be due to an Acute Coronary Syndrome.

Four-dimensional visualization of thoracic blood flow by magnetic resonance imaging in a patient following correction of transposition of the great arteries (d-TGA) and uncorrected aortic coarctation

Recent advances in flow-sensitive magnetic resonance imaging (MRI) and data analysis allow for comprehensive noninvasive three-dimensional (3D) visualization of complex blood flow. Electrocardiogram (ECG)-gated three-directional (3dir) flow measurements were employed to assess and visualize time-resolved 3D blood flow in the pulmonary arteries (PA) and thoracic aorta. We present findings in a juvenile patient with surgically corrected transposition of the great arteries (d-TGA) and aortic coarctation. For the first time, the complex flow patterns in the PA following d-TGA were visualized. Morphologically, a slight asymmetry of the PA was found, with considerable impact on vascular hemodynamics, resulting in diastolic retrograde flow in the larger vessel and diastolic filling of the smaller PA. Additionally, increased flow to the supraaortic vessels was found due to aortic coarctation.

Clinical application of MRI in children for the assessment of pulmonary diseases

The standard examination technique for the chest in children is an X-ray examination - it is fast, cheap and provides a good overview of anatomy and pathology. In cases with an unclear pathology or if more details are needed (i. e. pre-therapeutically), computed tomography is most often performed with the well known drawbacks of limited soft tissue contrast and radiation. Radiation should be avoided in children, especially if follow-up examinations are needed. Recent magnetic resonance (MR) techniques allow for fast and reliable assessment of pulmonary diseases in children. Due to the inherent soft tissue contrast, diagnosis can be frequently performed without contrast media application. This review provides an exemplary MR examination protocol for routine application in pediatric patients. The diagnostic value of MRI is shown in patients with infectious diseases, patients with immunodeficiency, anatomic abnormalities, acquired chronic diseases, and pulmonary tumors. Since MRI is especially suitable for functional imaging, an MR protocol is provided for the examination of thoracic deformities. This review summarizes the use of thoracic MRI in the clinical pediatric setting with special focus on the clinical indications as a radiation-free method.