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https://www.readbyqxmd.com/read/28227933/classification-of-severity-of-mitral-regurgitation-patients-using-multifractal-analysis
#1
Rijil Thomas, Ling Lieng Hsi, Soh Cheong Boon, Erry Gunawan, Rijil Thomas, Ling Lieng Hsi, Soh Cheong Boon, Erry Gunawan, Soh Cheong Boon, Erry Gunawan, Ling Lieng Hsi
Owing to its efficiency and cost effectiveness, auscultation using a stethoscope is the primary diagnosis method preferred by most medical examiners for cardiovascular disease. Phonocardiography (PCG) is the next level of auscultation and an effective analysis technique in cardiology. This paper presents a method to quantify Mitral Regurgitation (MR) using PCG. MR is one of the most common cardiovascular diseases associated with a defect in mitral valve. We analyzed the multifractal nature of heart sounds with murmur followed by classification and clustering using Hurst exponents...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227775/3d-anatomical-reconstruction-of-human-cardiac-conduction-system-and-simulation-of-bundle-branch-block-after-tavi-procedure
#2
Andrew J Atkinson, Sanjay R Kharche, Michael G Bateman, Paul A Iaizzo, Halina Dobrzynski, Andrew J Atkinson, Sanjay R Kharche, Michael G Bateman, Paul A Iaizzo, Halina Dobrzynski, Andrew J Atkinson, Paul A Iaizzo, Halina Dobrzynski, Sanjay R Kharche, Michael G Bateman
The cardiac conduction system (CCS) is responsible for the initiation and propagation of action potentials through the heart ensuring efficient pumping of blood. Understanding the anatomy of the CCS and its relationship with other major cardiac components is important to help understand arrhythmias and how certain procedures may increase the incidence of arrhythmias developing. We sectioned a whole human heart and performed Masson's trichrome histology in order to identify the components of the CCS. The histology images were used to construct a 3D anatomical model...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227467/a-simplified-state-space-model-of-biventricular-assist-device-cardiovascular-system-interaction
#3
Vivian C A Koh, Einly Lim, Boon Chiang Ng, Yong Kuen Ho, Nigel H Lovell, Vivian C A Koh, Einly Lim, Boon Chiang Ng, Yong Kuen Ho, Nigel H Lovell, Boon Chiang Ng, Einly Lim, Vivian C A Koh, Nigel H Lovell, Yong Kuen Ho
A simplified state-space model of biventricular assist device (BiVAD)-cardiovascular system (CVS) interaction is presented. The state-space equations includes a six-compartments CVS model incorporating the ventricles, the pulmonary and systemic circulations as well as the non-linear behavior of the valve flow, together with a left ventricular assist device (LVAD) and a right ventricular assist device (RVAD) component. The left and right pump speeds serve as the input variables for the state-space model. The model is simulated with three operational modes, i...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227466/engineering-based-assessment-for-a-shape-design-of-a-pediatric-eptfe-pulmonary-conduit-valve
#4
Yusuke Tsuboko, Yasuyuki Shiraishi, Akihiro Yamada, Tomoyuki Yambe, Hidekazu Miura, Seitaro Mura, Masaaki Yamagishi, Yusuke Tsuboko, Yasuyuki Shiraishi, Akihiro Yamada, Tomoyuki Yambe, Hidekazu Miura, Seitaro Mura, Masaaki Yamagishi, Akihiro Yamada, Seitaro Mura, Yasuyuki Shiraishi, Tomoyuki Yambe, Yusuke Tsuboko, Hidekazu Miura, Masaaki Yamagishi
The authors examined the hemodynamic characteristics of expanded polytetrafluoroethylene (ePTFE) pulmonary valved conduits quantitatively by our originally developed pediatric pulmonary mechanical circulatory system, in order to suggest the optimal shape design. The system consisted of pneumatically driven right atrium and ventricle model, a pulmonary valve chamber, and elastic pulmonary compliance model with peripheral vascular resistance units, a venous reservoir. We employed two different types of ePTFE valve and evaluated the relationship between the leaflets motion and hemodynamic characteristics by using a high-speed video camera...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227464/the-effect-of-the-aortic-valve-orientation-on-cavitation
#5
Peter Johansen, Brandon R Travis, Morten Smerup, Thomas Decker Christensen, Jonas Funder, Camilla Nyboe, Hans Nygaard, J Michael Hasenkam, Peter Johansen, Brandon R Travis, Morten Smerup, Thomas Decker Christensen, Jonas Funder, Camilla Nyboe, Hans Nygaard, J Michael Hasenkam, Brandon R Travis, Peter Johansen, Hans Nygaard, Morten Smerup, Jonas Funder, Camilla Nyboe, Thomas Decker Christensen, J Michael Hasenkam
When implanting a mechanical aortic valve the annulus orientation is important with respect to turbulence. However, the effect on cavitation has not yet been investigated. The aim of this study was to investigate how cavitation is influenced hereof in vivo. Three pigs were included in the study. An Omnicarbon 21mm valve equipped with a rotating mechanism enabling controlled rotation of the valve was implanted in aortic position. Under stable hemodynamic conditions, measurements were performed using a hydrophone positioned at the aortic root...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227286/indirect-measurement-of-the-carotid-arterial-pressure-from-vibrocardiographic-signal-calibration-of-the-waveform-and-comparison-with-photoplethysmographic-signal
#6
L Casacanditella, G Cosoli, S Casaccia, E P Tomasini, L Scalise, L Casacanditella, G Cosoli, S Casaccia, E P Tomasini, L Scalise, G Cosoli, S Casaccia, E P Tomasini, L Casacanditella, L Scalise
The detection of arterial Blood Pressure waveform provides important information about the subject health status. Laser Doppler Vibrometry (LDV) is a non-contact technique with high sensitivity able to detect mechanical movements of the arterial wall; several previous studies have shown that LDV is able to characterize cardiac activity. Photoplethysmogram (PPG) quantifies the digital volume artery pulse, which has been demonstrated to be closely related to the pressure signal measured by an arterial tonometer...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227216/prediction-of-individual-prosthesis-size-for-valve-sparing-aortic-root-reconstruction-based-on-geometric-features
#7
J Hagenah, E Werrmann, M Scharfschwerdt, F Ernst, C Metzner, J Hagenah, E Werrmann, M Scharfschwerdt, F Ernst, C Metzner, C Metzner, E Werrmann, J Hagenah, F Ernst, M Scharfschwerdt
Valve-sparing aortic root reconstruction is an up- and-coming approach for patients suffering from aortic valve insufficiencies which promises to significantly reduce complications. However, the success of the treatment strongly depends on the challenging task of choosing the correct size of the prosthesis, for which, up to now, surgeons solely have to rely on their experience. Here, we present a novel machine learning based approach, which might make it possible to predict the size of the prosthesis from pre-operatively acquired ultrasound images...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226778/simulation-of-motor-current-waveforms-in-monitoring-aortic-valve-state-during-ventricular-assist-device-support
#8
Khalid A Alonazi, Nigel H Lovell, Socrates Dokos, Khalid A Alonazi, Nigel H Lovell, Socrates Dokos, Khalid A Alonazi, Socrates Dokos, Nigel H Lovell
Monitoring of aortic valve (AV) opening and closure during left ventricular assist device (LVAD) heart pump support is crucial in preventing AV abnormalities and remodeling caused by anomalous resirculation. In this study, simulations of LVAD motor current waveforms were undertaken to investigate AV response to rotary blood pump assistance, as well as to detect AV open and close status under heart failure conditions. A two-dimensional fluid-structure interaction finite-element model is presented to predict AV state during LVAD outflow...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226688/mitral-valve-annulus-localization-in-3d-echocardiography
#9
Abhishek Tiwari, Kedar A Patwardhan, Abhishek Tiwari, Kedar A Patwardhan, Kedar A Patwardhan, Abhishek Tiwari
The Mitral Valve is a structure on the left side of the human heart that regulates the flow of oxygenated blood into the Left Ventricle and also helps maintain the pressure within the Left Ventricle when the blood gets pumped to the rest of the body from the Left Ventricle. Pathology of the Mitral Valve often manifests through structural changes in the anatomy. Assessment of Mitral Valve pathology as well as determination of specific interventions require quantification of various structures of the Mitral Valve and one of these structures of interest is the Mitral Valve annulus...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226685/tracking-of-the-anterior-mitral-leaflet-in-echocardiographic-sequences-using-active-contours
#10
Malik Saad Sultan, Nelson Martins, Diana Veiga, Manuel Joao Ferreira, Miguel Tavares Coimbra, Malik Saad Sultan, Nelson Martins, Diana Veiga, Manuel Joao Ferreira, Miguel Tavares Coimbra, Diana Veiga, Nelson Martins, Malik Saad Sultan, Miguel Tavares Coimbra, Manuel Joao Ferreira
Echocardiography assessment of cardiac valves plays a vital role in the diagnosis of rheumatic heart disease. In the vast majority of cases, the mitral valve gets affected, leading to the thickening of its leaflets that may result in the fusion of their tips. This changes the appearance and reduces the mobility of the leaflets, which also reduce the heart efficiency. Quantifying such parameters provides diagnostic insight. To achieve that, the first step is to identify and then track fast moving leaflets. This work is focused on Anterior Mitral Leaflet (AML) tracking...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226476/ultrasound-characterization-of-interface-oscillation-as-a-proxy-for-ventriculoperitoneal-shunt-function
#11
April Joy C Aralar, Matthew D Bird, Robert D Graham, Beomseo Koo, Mahesh B Shenai, Parag V Chitnis, Siddhartha Sikdar, April Joy C Aralar, Matthew D Bird, Robert D Graham, Beomseo Koo, Mahesh B Shenai, Parag V Chitnis, Siddhartha Sikdar, Mahesh B Shenai, Beomseo Koo, Robert D Graham, Matthew D Bird, Siddhartha Sikdar, Parag V Chitnis, April Joy C Aralar
Hydrocephalus, where cerebrospinal fluid (CSF) production rate is greater than reabsorption rate, leads to impaired neurological function if left untreated. Ventriculoperitoneal shunts (VPS) are implanted in the brain ventricles to route CSF. VPS systems have a high failure rate, and failure symptoms resemble symptoms of common maladies. The current gold standard for shunt diagnosis, surgical intervention, poses high risk and requires an expensive procedure for patients. Current non-invasive methods lack proper insight to assist physicians...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28225837/storage-time-of-intraoperative-transfused-allogeneic-red-blood-cells-is-not-associated-with-new-onset-postoperative-atrial-fibrillation-in-cardiac-surgery
#12
Jiwei Gu, Regitze Kuhr Skals, Christian Torp-Pedersen, Søren Lundbye-Christensen, Carl-Johan Jakobsen, John Bæch, Mikkel Steen Petersen, Jan Jesper Andreasen
BACKGROUND: Allogeneic red blood cell (RBC) transfusion has been associated with new-onset postoperative atrial fibrillation (POAF) following cardiac surgery. Prolonged storage time of RBC may increase the risk. The primary aim of the study was to evaluate whether the storage time of RBC is associated with development of POAF. MATERIALS AND METHODS: Pre-, per- and postoperative data were retrieved from the Western Denmark Heart Registry and local blood banks regarding patients who underwent coronary artery bypass surgery, valve surgery or combined procedures in Aalborg or Aarhus University Hospital during 2010-2014...
2017: PloS One
https://www.readbyqxmd.com/read/28225836/analysis-of-immune-cell-populations-in-atrial-myocardium-of-patients-with-atrial-fibrillation-or-sinus-rhythm
#13
Natalia Smorodinova, Martin Bláha, Vojtěch Melenovský, Karolína Rozsívalová, Jaromír Přidal, Mária Ďurišová, Jan Pirk, Josef Kautzner, Tomáš Kučera
BACKGROUND: Atrial fibrillation (AF) is the most common arrhythmia and despite obvious clinical importance remains its pathogenesis only partially explained. A relation between inflammation and AF has been suggested by findings of increased inflammatory markers in AF patients. OBJECTIVE: The goal of this study was to characterize morphologically and functionally CD45-positive inflammatory cell populations in atrial myocardium of patients with AF as compared to sinus rhythm (SR)...
2017: PloS One
https://www.readbyqxmd.com/read/28225640/absolute-delay-multiphase-reconstruction-reduces-prosthetic-valve-related-and-atrial-fibrillation-related-artifacts-at-cardiac-ct
#14
Young Joo Suh, Dong Jin Im, Yoo Jin Hong, Hye-Jeong Lee, Jin Hur, Byoung Wook Choi, Young Jin Kim
OBJECTIVE: The objective of our study was to compare the image quality of cardiac CT images of mechanical valves in patients with irregular heart rates (HRs) using absolute-delay multiphase reconstruction versus relative-delay multiphase reconstruction. MATERIALS AND METHODS: A total of 26 patients with 40 mechanical valves who had atrial fibrillation during CT were included. The image quality of the CT scans was assessed for the subvalvular and valvular regions on a 4-point scale...
February 22, 2017: AJR. American Journal of Roentgenology
https://www.readbyqxmd.com/read/28225135/liquid-metal-enabled-microfluidics
#15
Khashayar Khoshmanesh, Shi-Yang Tang, Jiu Yang Zhu, Samira Schaefer, Arnan Mitchell, Kourosh Kalantar-Zadeh, Michael D Dickey
Several gallium-based liquid metal alloys are liquid at room temperature. As 'liquid', such alloys have a low viscosity and a high surface tension while as 'metal', they have high thermal and electrical conductivities, similar to mercury. However, unlike mercury, these liquid metal alloys have low toxicity and a negligible vapor pressure, rendering them much safer. In comparison to mercury, the distinguishing feature of these alloys is the rapid formation of a self-limiting atomically thin layer of gallium oxide over their surface when exposed to oxygen...
February 22, 2017: Lab on a Chip
https://www.readbyqxmd.com/read/28224933/inadequacy-of-existing-clinical-prediction-models-for-predicting-mortality-after-transcatheter-aortic-valve-implantation
#16
Glen P Martin, Matthew Sperrin, Peter F Ludman, Mark A de Belder, Chris P Gale, William D Toff, Neil E Moat, Uday Trivedi, Iain Buchan, Mamas A Mamas
BACKGROUND: The performance of emerging transcatheter aortic valve implantation (TAVI) clinical prediction models (CPMs) in national TAVI cohorts distinct from those where they have been derived is unknown. This study aimed to investigate the performance of the German Aortic Valve, FRANCE-2, OBSERVANT and American College of Cardiology (ACC) TAVI CPMs compared with the performance of historic cardiac CPMs such as the EuroSCORE and STS-PROM, in a large national TAVI registry. METHODS: The calibration and discrimination of each CPM were analyzed in 6676 patients from the UK TAVI registry, as a whole cohort and across several subgroups...
February 2017: American Heart Journal
https://www.readbyqxmd.com/read/28224928/impact-of-right-ventricular-function-on-outcome-of-severe-aortic-stenosis-patients-undergoing-transcatheter-aortic-valve-replacement
#17
Edward Koifman, Romain Didier, Nirav Patel, Zack Jerusalem, Sarkis Kiramijyan, Itsik Ben-Dor, Smita I Negi, Zuyue Wang, Steven A Goldstein, Michael J Lipinski, Rebecca Torguson, Jiaxiang Gai, Augusto D Pichard, Lowell F Satler, Ron Waksman, Federico M Asch
BACKGROUND: Right ventricular (RV) dysfunction was shown to be associated with adverse outcomes in a variety of cardiac patients and is considered a risk factor for adverse outcome according to the updated Valve Academic Research Consortium criteria. OBJECTIVE: Our goal was to assess the impact of RV function at baseline on 1-year mortality among patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR). METHODS: All patients with severe AS treated with TAVR from May 2007 to March 2015 at our center were included in the present study, and baseline and procedural characteristics were recorded for each patient...
February 2017: American Heart Journal
https://www.readbyqxmd.com/read/28224910/identification-of-sink-spots-in-two-thermal-desorption-gc-ms-systems-for-the-analysis-of-polycyclic-aromatic-hydrocarbons
#18
Yingjie Li, Jiping Zhu
Thermal desorption (TD) GC/MS has been used for the analysis of polycyclic aromatic hydrocarbons (PAHs) and other semi-volatile organic compounds. However, thermal desorption recovery of PAHs have not been well studied and the cause of PAH residues in a TD system has not been clearly understood. Our results showed that low volatility of PAHs can lead to their incomplete recovery in a TD system: for the PAHs with low vapour pressures, up to 10% and 3% could be lost in a two-stage (TS) TD system and a short-path (SP) TD system, respectively...
April 8, 2017: Analytica Chimica Acta
https://www.readbyqxmd.com/read/28224661/recurrent-obstructive-fibrinous-tracheal-pseudomembranes-in-a-young-english-bulldog
#19
E Robin, L V Guieu, K Le Boedec
Endotracheal intubation is a common procedure, rarely associated with life-threatening complications (e.g., tracheal rupture, necrosis, foreign body). A 1.5-year-old English Bulldog was presented for respiratory distress, with increased respiratory efforts and stridor, 2 days after endotracheal intubation. Cervical and thoracic radiographs disclosed a severe narrowing of the tracheal lumen associated with an intraluminal soft-tissue structure at the thoracic inlet. Tracheoscopy confirmed the presence of an obstructive fibrinous tracheal pseudomembrane (OFTP) creating a 1-way valve obstruction...
February 22, 2017: Journal of Veterinary Internal Medicine
https://www.readbyqxmd.com/read/28224405/complications-of-acromegaly-cardiovascular-respiratory-and-metabolic-comorbidities
#20
REVIEW
Rosario Pivonello, Renata S Auriemma, Ludovica F S Grasso, Claudia Pivonello, Chiara Simeoli, Roberta Patalano, Mariano Galdiero, Annamaria Colao
Acromegaly is associated with an enhanced mortality, with cardiovascular and respiratory complications representing not only the most frequent comorbidities but also two of the main causes of deaths, whereas a minor role is played by metabolic complications, and particularly diabetes mellitus. The most prevalent cardiovascular complications of acromegaly include a cardiomyopathy, characterized by cardiac hypertrophy and diastolic and systolic dysfunction together with arterial hypertension, cardiac rhythm disorders and valve diseases, as well as vascular endothelial dysfunction...
February 21, 2017: Pituitary
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