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https://www.readbyqxmd.com/read/27913507/diagnosis-of-suspected-venous-thromboembolism
#1
Clive Kearon
The primary goal of diagnostic testing for venous thromboembolism (VTE) is to identify all patients who could benefit from anticoagulant therapy. Test results that identify patients as having a ≤2% risk of VTE in the next 3 months are judged to exclude deep vein thrombosis (DVT) or pulmonary embolism (PE). Clinical evaluation, with assessment of: (1) clinical pretest probability (CPTP) for VTE; (2) likelihood of important alternative diagnoses; and (3) the probable yield of D-dimer and various imaging tests, guide which tests should be performed...
December 2, 2016: Hematology—the Education Program of the American Society of Hematology
https://www.readbyqxmd.com/read/27886421/pathophysiology-of-dyspnoea-in-acute-pulmonary-embolism-a-cross-sectional-evaluation
#2
Olivier Sanchez, Aurore Caumont-Prim, Elisabeth Riant, Laurent Plantier, Martin Dres, Bruno Louis, Marie-Anne Collignon, Benoit Diebold, Guy Meyer, Claudine Peiffer, Christophe Delclaux
BACKGROUND AND OBJECTIVE: Dyspnoea in pulmonary embolism (PE) remains poorly characterized. Little is known about how to measure intensity or about the underlying mechanisms that may be related to ventilatory abnormalities, alveolar dead space ventilation or modulating factors such as psychological modulate. We hypothesized that dyspnoea would mainly be associated with pulmonary vascular obstruction and its pathophysiological consequences, while the sensory-affective domain of dyspnoea would be influenced by other factors...
November 25, 2016: Respirology: Official Journal of the Asian Pacific Society of Respirology
https://www.readbyqxmd.com/read/27820928/pulmonary-perfusion-changes-as-assessed-by-contrast-enhanced-dual-energy-computed-tomography-after-endoscopic-lung-volume-reduction-by-coils
#3
Frédéric Lador, Anne-Lise Hachulla, Olivia Hohn, Jérôme Plojoux, Maxime Ronot, Xavier Montet, Paola M Soccal
BACKGROUND: Endoscopic lung volume reduction by coils (LVRC) is a recent treatment approach for severe emphysema. Furthermore, dual-energy computed tomography (DECT) now offers a combined assessment of lung morphology and pulmonary perfusion. OBJECTIVES: The aim of our study was to assess the impact of LVRC on pulmonary perfusion with DECT. METHODS: Seventeen patients (64.8 ± 6.7 years) underwent LVRC. DECT was performed prior to and after LVRC...
2016: Respiration; International Review of Thoracic Diseases
https://www.readbyqxmd.com/read/27816974/troponin-i-and-d-dimer-for-discriminating-acute-pulmonary-thromboembolism-from-myocardial-infarction
#4
Soo Jin Kim, Moo Hyun Kim, Kwang Min Lee, Tae Hyung Kim, Sun Yong Choi, Min Kook Son, Ji Woen Park, Victor L Serebruany
BACKGROUND: Acute pulmonary thromboembolism (APTE) is a life-threatening condition, often manifesting with chest pain, dyspnea, and increased cardiac biomarkers including cardiac troponin I (CTI) and D-dimer. Therefore, APTE is often misdiagnosed with classical non-ST elevation myocardial infarction (NSTEMI), resulting in unnecessary coronary interventions and a delay of therapy. OBJECTIVES: Our aim was to distinguish APTE from NSTEMI based on CTI and D-dimer levels...
November 5, 2016: Cardiology
https://www.readbyqxmd.com/read/27815969/residual-pulmonary-vascular-obstruction-and-recurrence-after-acute-pulmonary-embolism-a-single-center-cohort-study
#5
Benjamin Planquette, Alexis Ferré, Julien Peron, Amandine Vial-Dupuy, Jean Pastre, Gisèle Mourin, Joseph Emmerich, Marie-Anne Collignon, Guy Meyer, Olivier Sanchez
INTRODUCTION: Up to 50% of patients with pulmonary embolism (PE) present lung perfusion defects after six months of anticoagulant treatment, suggesting residual pulmonary vascular obstruction (RPVO). The risk of recurrence in patients with RPVO remains unknown. The present study aims to assess the risk of recurrent venous thromboembolism (VTE) in patients with RPVO after a first symptomatic episode of PE. METHODS: Consecutive patients who survived a first objectively proven acute PE, treated for at least three months with anticoagulants, were included and followed prospectively...
October 29, 2016: Thrombosis Research
https://www.readbyqxmd.com/read/27815261/soluble-epoxide-hydrolase-deficiency-or-inhibition-enhances-murine-hypoxic-pulmonary-vasoconstriction-after-lipopolysaccharide-challenge
#6
Martin Wepler, Arkadi Beloiartsev, Mary D Buswell, Dipak Panigrahy, Rajeev Malhotra, Emmanuel S Buys, Peter Radermacher, Fumito Ichinose, Donald B Bloch, Warren M Zapol
RATIONALE: Hypoxic pulmonary vasoconstriction (HPV) is the response of the pulmonary vasculature to low levels of alveolar oxygen. HPV improves systemic arterial oxygenation by matching pulmonary perfusion to ventilation during alveolar hypoxia, and is impaired in lung diseases such as the acute respiratory distress syndrome (ARDS) and in experimental models of endotoxemia. Epoxyeicosatrienoic acids (EETs) are pulmonary vasoconstrictors, which are metabolized to less vasoactive dihydroxyeicosatrienoic acids (DHETs) by soluble epoxide hydrolase (sEH)...
November 4, 2016: American Journal of Physiology. Lung Cellular and Molecular Physiology
https://www.readbyqxmd.com/read/27797317/prevalence-of-pulmonary-embolism-among-patients-hospitalized-for-syncope
#7
Paolo Prandoni, Anthonie W A Lensing, Martin H Prins, Maurizio Ciammaichella, Marica Perlati, Nicola Mumoli, Eugenio Bucherini, Adriana Visonà, Carlo Bova, Davide Imberti, Stefano Campostrini, Sofia Barbar
Background The prevalence of pulmonary embolism among patients hospitalized for syncope is not well documented, and current guidelines pay little attention to a diagnostic workup for pulmonary embolism in these patients. Methods We performed a systematic workup for pulmonary embolism in patients admitted to 11 hospitals in Italy for a first episode of syncope, regardless of whether there were alternative explanations for the syncope. The diagnosis of pulmonary embolism was ruled out in patients who had a low pretest clinical probability, which was defined according to the Wells score, in combination with a negative d-dimer assay...
October 20, 2016: New England Journal of Medicine
https://www.readbyqxmd.com/read/27793158/clinical-and-echocardiographic-predictors-of-mortality-in-acute-pulmonary-embolism
#8
Talal Dahhan, Irfan Siddiqui, Victor F Tapson, Eric J Velazquez, Stephanie Sun, Clemontina A Davenport, Zainab Samad, Sudarshan Rajagopal
PURPOSE: The aim of this study was to evaluate the utility of adding quantitative assessments of cardiac function from echocardiography to clinical factors in predicting the outcome of patients with acute pulmonary embolism (PE). METHODS: Patients with a diagnosis of acute PE, based on a positive ventilation perfusion scan or computed tomography (CT) chest angiogram, were identified using the Duke University Hospital Database. Of these, 69 had echocardiograms within 24-48 h of the diagnosis that were suitable for offline analysis...
October 28, 2016: Cardiovascular Ultrasound
https://www.readbyqxmd.com/read/27784118/c-arm-computed-tomography-adds-diagnostic-information-in-patients-with-chronic-thromboembolic-pulmonary-hypertension-and-a-positive-v-q-spect
#9
J B Hinrichs, T Werncke, T Kaireit, M M Hoeper, K M Olsson, J C Kamp, F K Wacker, F Bengel, C von Falck, I Schatka, B C Meyer
Purpose: To determine if C-Arm computed tomography (CACT) has added diagnostic value in patients suffering from chronic thromboembolic pulmonary hypertension (CTEPH) with a positive mismatch pattern in ventilation/perfusion single photon emission computed tomography (V/Q SPECT). Materials and Methods: 28 patients (23 men, 5 women, 62 ± 18 years) with CTEPH who had undergone SPECT, followed by CACT and right heart catheterization (RHC) were included. Two independent readers reviewed SPECT and CACT. Findings indicating CTEPH and their location (segmental or sub-segmental) were identified (V/Q mismatch in SPECT and vascular pathologies in CACT)...
October 26, 2016: RöFo: Fortschritte Auf Dem Gebiete der Röntgenstrahlen und der Nuklearmedizin
https://www.readbyqxmd.com/read/27764879/state-of-the-art-imaging-in-pulmonary-embolism-ventilation-perfusion-single-photon-emission-computed-tomography-versus-computed-tomography-angiography-controversies-results-and-recommendations-from-a-systematic-review
#10
Søren Hess, Evan C Frary, Oke Gerke, Poul Henning Madsen
Pulmonary embolism (PE) is a common, ubiquitous, and potentially lethal disease. As symptoms and clinical findings are notoriously nonspecific, diagnostic imaging is essential to avoid undertreatment as well as overtreatment. Controversies remain regarding first-line imaging in suspected PE. The two main contemporary contenders are ventilation/perfusion scintigraphy with single-photon emission computed tomography (V/Q SPECT) with or without additional low-dose CT (SPECT/CT) and CT angiography (CTA). We present our results from a systematic review and meta-analysis of the diagnostic performances of these modalities: V/Q SPECT, V/Q SPECT/CT, and CTA are all viable options, but we consider V/Q SPECT/CT to be superior in most clinical settings with better overall diagnostic performance, that is, pooled sensitivities (97...
October 20, 2016: Seminars in Thrombosis and Hemostasis
https://www.readbyqxmd.com/read/27758995/pulmonary-stenting-for-the-treatment-of-sarcoid-induced-pulmonary-vascular-stenosis
#11
Jose F Condado, Vasilis Babaliaros, Travis S Henry, Brian Kaebnick, Dennis Kim, Gerald W Staton
BACKGROUND: The best treatment of patients with external pulmonary vascular compression due to advanced sarcoidosis is unknown. OBJECTIVES: To report a single-center experience of percutaneous treatment for pulmonary vascular stenosis caused by external compression due to advanced sarcoidosis. METHODS: We report a case series of 5 patients with biopsy confirmed advanced sarcoidosis, seen at our academic institution with worsening dyspnea despite increase of immunosuppressive therapy...
October 7, 2016: Sarcoidosis, Vasculitis, and Diffuse Lung Diseases: Official Journal of WASOG
https://www.readbyqxmd.com/read/27739872/the-clinical-significance-of-collateral-ventilation
#12
Peter B Terry, Richard J Traystman
Oxygen delivery and carbon dioxide removal being critical to cell survival, mammals have developed collateral vascular and ventilation systems to ensure tissue viability. Collateral ventilation, defined as ventilation of alveoli via pathways that bypass normal airways, is present in humans and many other species. The presence of collateral ventilation can be beneficial in certain disease states, whereas its relative absence can predispose to other diseases. These well defined anatomical pathways contribute little to ventilation in normal humans, but modulate ventilation perfusion imbalance in a variety of diseases, including obstructive diseases, such as asthma and emphysema...
December 2016: Annals of the American Thoracic Society
https://www.readbyqxmd.com/read/27726408/overview-of-the-novel-and-improved-pulmonary-ventilation-perfusion-imaging-applications-in-the-era-of-spect-ct
#13
Saeed Elojeimy, Irene Cruite, Stephen Bowen, Jing Zeng, Hubert Vesselle
OBJECTIVE: In this article, we describe the concepts of ventilation-perfusion planar, SPECT, and SPECT/CT and outline the advantages of integrated ventilation-perfusion SPECT/CT over planar imaging. We present an overview of the traditional and new applications of ventilation-perfusion scintigraphy. CONCLUSION: SPECT/CT has improved the diagnostic accuracy of ventilation-perfusion imaging and opened the door for a new spectrum of applications.
December 2016: AJR. American Journal of Roentgenology
https://www.readbyqxmd.com/read/27719980/imaging-of-pulmonary-hypertension
#14
Christopher J François, Mark L Schiebler
Multimodality, noninvasive imaging is increasingly used in the identification and management of pulmonary hypertension (PH). Chest radiography, ventilation-perfusion scintigraphy, and Doppler echocardiography are frequently the initial studies used to evaluate patients suspected of having PH. However, their ability to evaluate the right ventricle (RV) and pulmonary vasculature is limited. Computed tomography (CT) and magnetic resonance (MR) imaging are increasingly used to identify causes of PH and assess the effect of PH on RV function...
November 2016: Radiologic Clinics of North America
https://www.readbyqxmd.com/read/27701117/role-of-acid-sphingomyelinase-and-il-6-as-mediators-of-endotoxin-induced-pulmonary-vascular-dysfunction
#15
Rachele Pandolfi, Bianca Barreira, Enrique Moreno, Victor Lara-Acedo, Daniel Morales-Cano, Andrea Martínez-Ramas, Beatriz de Olaiz Navarro, Raquel Herrero, José Ángel Lorente, Ángel Cogolludo, Francisco Pérez-Vizcaíno, Laura Moreno
BACKGROUND: Pulmonary hypertension (PH) is frequently observed in patients with acute respiratory distress syndrome (ARDS) and it is associated with an increased risk of mortality. Both acid sphingomyelinase (aSMase) activity and interleukin 6 (IL-6) levels are increased in patients with sepsis and correlate with worst outcomes, but their role in pulmonary vascular dysfunction pathogenesis has not yet been elucidated. Therefore, the aim of this study was to determine the potential contribution of aSMase and IL-6 in the pulmonary vascular dysfunction induced by lipopolysaccharide (LPS)...
July 27, 2016: Thorax
https://www.readbyqxmd.com/read/27698722/analysis-of-the-first-therapeutic-target-achieving-time-of-warfarin-therapy-and-associated-factors-in-patients-with-pulmonary-embolism
#16
Xiaowei Gong, Haiyan Wang, Yadong Yuan
The present study aimed to investigate the factors affecting the first therapeutic-target-achieving (TTA) time of warfarin therapy in patients with acute pulmonary embolism (PTE). Between January 2008 and June 2013, patients with PTE confirmed by transpulmonary arterial enhanced computed tomographic pulmonary angiography or pulmonary ventilation perfusion scanning were included in the present study. Data collected included demographic information, history of tobacco and alcohol intake, basic diseases (stable and unstable hypertension, diabetes, heart failure, cancer/cerebral infarction, old myocardial infarction and atrial fibrillation), liver and kidney function, the haemoglobin and platelet count of the blood, international normalized ratio monitoring, warfarin dosage adjustment and medication combinations...
October 2016: Experimental and Therapeutic Medicine
https://www.readbyqxmd.com/read/27679963/pulmonary-hypertension-associated-with-chronic-lung-diseases
#17
Manuela Funke, Thomas Geiser, Otto D Schoch
In 2015, the international guidelines for diagnosis and treatment of pulmonary hypertension (PH) were updated. Group 3 of the current classification includes PH associated with chronic obstructive pulmonary disease (COPD), interstitial lung disease (ILD), other pulmonary diseases with restrictive and obstructive pattern, sleep-disordered breathing, alveolar hypoventilation disorders, chronic exposure to high altitude, and developmental lung diseases [1]. PH associated with COPD and ILD is common but difficult to manage, as no long-term randomised controlled trial (RCT) has been conducted with specific pulmonary arterial hypertension (PAH) drugs in PH associated with COPD, and the one recent RCT in PH associated with ILD had to be stopped early due to a possible increased risk of death and side effects in the treatment group...
2016: Swiss Medical Weekly
https://www.readbyqxmd.com/read/27660298/case-studies-in-physiology-ventilation-and-perfusion-in-a-giraffe-does-size-matter
#18
Gorel Nyman, Bengt Röken, Eva-Maria Hedin, Goran Hedenstierna
The trachea in the giraffe is long but narrow and dead space ventilation is in general considered to be of similar size as in other mammals. Less is known about matching of ventilation and lung blood flow. The lungs are large, up to 1 m high and 0.7 m wide, that may cause considerable ventilation/perfusion (VA/Q) mis-match by the influence of gravitational forces, leading to hypoxemia. We studied a young giraffe under anesthesia utilizing multiple inert gas elimination technique to analyze VA/Q distribution and arterial oxygenation and compared the results with other species of different sizes, including man...
September 22, 2016: Journal of Applied Physiology
https://www.readbyqxmd.com/read/27645688/hypoxic-pulmonary-vasoconstriction-from-molecular-mechanisms-to-medicine
#19
Kimberly J Dunham-Snary, Danchen Wu, Edward A Sykes, Amar Thakrar, Leah Rg Parlow, Jeffrey D Mewburn, Joel L Parlow, Stephen L Archer
Hypoxic pulmonary vasoconstriction (HPV) is a homeostatic mechanism that is intrinsic to the pulmonary vasculature. Intrapulmonary arteries constrict in response to alveolar hypoxia, diverting blood to better-oxygenated lung segments, thereby optimizing ventilation-perfusion matching and systemic oxygen delivery. In response to alveolar hypoxia, a mitochondrial sensor dynamically changes reactive oxygen species and redox couples in PASMC. This inhibits potassium channels, depolarizes PASMC, activates voltage-gated calcium channels, and increases cytosolic calcium, causing vasoconstriction...
September 16, 2016: Chest
https://www.readbyqxmd.com/read/27634820/development-and-preclinical-testing-of-an-adaptive-algorithm-for-automated-control-of-inspired-oxygen-in-the-preterm-infant
#20
Peter A Dargaville, Omid Sadeghi Fathabadi, Gemma K Plottier, Kathleen Lim, Kevin I Wheeler, Rohan Jayakar, Timothy J Gale
OBJECTIVE: To assess the performance of a novel algorithm for automated oxygen control using a simulation of oxygenation founded on in vivo data from preterm infants. METHODS: A proportional-integral-derivative (PID) control algorithm was enhanced by (i) compensation for the non-linear SpO2-PaO2 relationship, (ii) adaptation to the severity of lung dysfunction and (iii) error attenuation within the target range. Algorithm function with and without enhancements was evaluated by iterative linking with a computerised simulation of oxygenation...
September 15, 2016: Archives of Disease in Childhood. Fetal and Neonatal Edition
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