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https://www.readbyqxmd.com/read/27920480/comparison-of-multichannel-intraluminal-impedance-ph-monitoring-and-reflux-scintigraphy-in-pediatric-patients-with-suspected-gastroesophageal-reflux
#1
Nuray Uslu Kızılkan, Murat Fani Bozkurt, Inci Nur Saltık Temizel, Hülya Demir, Aysel Yüce, Biray Caner, Hasan Özen
AIM: To evaluate the agreement of multichannel intraluminal impedance-pH monitoring (MII-pHM) and gastroesophageal reflux scintigraphy (GES) for the diagnosis of gastroesophageal reflux disease. METHODS: Seventy-five consecutive patients with suspected gastroesophageal reflux disease (GERD) underwent 24-h combined MII-pHM recording and one hour radionuclide scintigraphy during the course of the MII-pHM study. Catheters with 6 impedance channels and 1 pH sensor were placed transnasally...
November 21, 2016: World Journal of Gastroenterology: WJG
https://www.readbyqxmd.com/read/27909471/contact-force-and-atrial-fibrillation-ablation
#2
REVIEW
Ullah W, Schilling Rj, Wong T
Catheters able to measure the force and vector of contact between the catheter tip and myocardium are now available. Pre-clinical work has established that the degree of contact between the radiofrequency ablation catheter and myocardium correlates with the size of the delivered lesion. Excess contact is associated with steam pops and perforation. Catheter contact varies within the left atrium secondary to factors including respiration, location, atrial rhythm and the trans-septal catheter delivery technology used...
February 2016: Journal of Atrial Fibrillation
https://www.readbyqxmd.com/read/27789351/cu-blood-flow-model-through-a-catheterized-mild-stenotic-artery-with-a-thrombosis
#3
Thanaa Elnaqeeb, Khaled S Mekheimer, Felwah Alghamdi
Copper nanoparticles blood flow analysis through a catheterized mild stenotic artery with a thrombosis is presented. The system of coupled governing equations are prescribed and then simplified under mild stenosis assumptions. The governing equations are solved exactly, and then expressions for temperature, axial velocity, stream function, wall shear stress and resistance impedance are obtained generally for metallic nanoparticles blood flow. Due to the importance of copper nanoparticles in biomedicine, the results for Cu-blood flow model are introduced...
December 2016: Mathematical Biosciences
https://www.readbyqxmd.com/read/27788384/blood-vessel-modeling-for-interactive-simulation-of-interventional-neuroradiology-procedures
#4
E Kerrien, A Yureidini, J Dequidt, C Duriez, R Anxionnat, S Cotin
Endovascular interventions can benefit from interactive simulation in their training phase but also during pre-operative and intra-operative phases if simulation scenarios are based on patient data. A key feature in this context is the ability to extract, from patient images, models of blood vessels that impede neither the realism nor the performance of simulation. This paper addresses both the segmentation and reconstruction of the vasculature from 3D Rotational Angiography data, and adapted to simulation: An original tracking algorithm is proposed to segment the vessel tree while filtering points extracted at the vessel surface in the vicinity of each point on the centerline; then an automatic procedure is described to reconstruct each local unstructured point set as a skeleton-based implicit surface (blobby model)...
October 14, 2016: Medical Image Analysis
https://www.readbyqxmd.com/read/27778419/baseline-impedance-measured-during-high-resolution-esophageal-impedance-manometry-reliably-discriminates-gerd-patients
#5
K Ravi, D M Geno, M F Vela, M D Crowell, D A Katzka
BACKGROUND: Baseline impedance measured with ambulatory impedance pH monitoring (MII-pH) and a mucosal impedance catheter detects gastroesophageal reflux disease (GERD). However, these tools are limited by cost or patient tolerance. We investigated whether baseline impedance measured during high-resolution impedance manometry (HRIM) distinguishes GERD patients from controls. METHODS: Consecutive patients with clinical HRIM and MII-pH testing were identified. Gastroesophageal reflux disease was defined by esophageal pH <4 for ≥5% of both the supine and total study time, whereas controls had an esophageal pH <4 for ≤3% of the study performed off PPI...
October 24, 2016: Neurogastroenterology and Motility: the Official Journal of the European Gastrointestinal Motility Society
https://www.readbyqxmd.com/read/27773967/ultrasonic-transducer-guided-electrochemical-impedance-spectroscopy-to-assess-lipid-laden-plaques
#6
Jianguo Ma, Yuan Luo, René R Sevag Packard, Teng Ma, Yichen Ding, Parinaz Abiri, Yu-Chong Tai, Qifa Zhou, Kirk K Shung, Rongsong Li, Tzung Hsiai
Plaque rupture causes acute coronary syndromes and stroke. Intraplaque oxidized low density lipoprotein (oxLDL) is metabolically unstable and prone to induce rupture. We designed an intravascular ultrasound (IVUS)-guided electrochemical impedance spectroscopy (EIS) sensor to enhance the detection reproducibility of oxLDL-laden plaques. The flexible 2-point micro-electrode array for EIS was affixed to an inflatable balloon anchored onto a co-axial double layer catheter (outer diameter = 2 mm). The mechanically scanning-driven IVUS transducer (45 MHz) was deployed through the inner catheter (diameter = 1...
November 1, 2016: Sensors and Actuators. B, Chemical
https://www.readbyqxmd.com/read/27754040/os-13-06-generation-of-aortic-flow-velocity-from-derived-aortic-pressure-waveforms-using-age-specific-aortic-impedance-modelling
#7
Audrey Adji, Thomas Weber, Caroline O'Brien, Michael O'Rourke, Alberto Avolio
OBJECTIVE: Relative ease of estimating of Ascending Aortic (AA) pressure non-invasively enables interpretation of age-related pressure waveform changes due to altered pulse wave propagation. AA flow velocity waveforms, measured invasively by ElectroMagnetic (EM) cuff/ catheter, and non-invasively by Cardiac Magnetic Resonance (CMR) also show characteristic aging changes attributable to aortic dilation and subtle impairment of Left Ventricular (LV) function. Conventional Doppler waveforms do not...
September 2016: Journal of Hypertension
https://www.readbyqxmd.com/read/27738965/how-to-optimally-apply-impedance-in-the-evaluation-of-esophageal-dysmotility
#8
Amit Patel, C Prakash Gyawali
The utilization of impedance technology has enhanced our understanding and assessment of esophageal dysmotility. Esophageal high-resolution manometry (HRM) catheters incorporated with multiple impedance electrodes help assess esophageal bolus transit, and the combination is termed high-resolution impedance manometry (HRIM). Novel metrics have been developed with HRIM-including esophageal impedance integral ratio, bolus flow time, nadir impedance pressure, and impedance bolus height-that augments the assessment of esophageal bolus transit...
November 2016: Current Gastroenterology Reports
https://www.readbyqxmd.com/read/27702853/left-atrial-model-reconstruction-in-atrial-fibrillation-ablation-reliability-of-new-mapping-and-complex-impedance-systems
#9
Aldo Bonso, Mauro Fantinel, Giovanna Scalchi, Sabrina Ferrara, Stefano Indiani, Federico Calore, Claudia Licciardello
AIMS: The effectiveness of atrial fibrillation (AF) ablation relies on detailed knowledge of the anatomy of the left atrium (LA) and pulmonary veins (PVs). It is common to combine computed tomography/magnetic resonance (CT/MR) with imaging by electroanatomical (EA) mapping systems. The aim of this study was to evaluate the accuracy of LA anatomical reconstruction by 'One Model' and 'VeriSense' tools (Ensite Velocity 3.0, St Jude Medical), compared with CT/MR imaging. METHODS AND RESULTS: Seventy-two patients with AF underwent pre-procedural imaging (97% CT-scan, 3% MR imaging) and transcatheter ablation of PVs...
October 4, 2016: Europace: European Pacing, Arrhythmias, and Cardiac Electrophysiology
https://www.readbyqxmd.com/read/27683632/hemodynamic-monitoring-in-heart-failure-and-pulmonary-hypertension-from-analog-tracings-to-the-digital-age
#10
REVIEW
Ryan Davey, Amresh Raina
Hemodynamic monitoring has long formed the cornerstone of heart failure (HF) and pulmonary hypertension diagnosis and management. We review the long history of invasive hemodynamic monitors initially using pulmonary artery (PA) pressure catheters in the hospital setting, to evaluating the utility of a number of implantable devices that can allow for ambulatory determination of intracardiac pressures. Although the use of indwelling PA catheters has fallen out of favor in a number of settings, implantable devices have afforded clinicians an opportunity for objective determination of a patient's volume status and pulmonary pressures...
September 24, 2016: World Journal of Transplantation
https://www.readbyqxmd.com/read/27642958/os-13-06-generation-of-aortic-flow-velocity-from-derived-aortic-pressure-waveforms-using-age-specific-aortic-impedance-modelling
#11
Audrey Adji, Thomas Weber, Caroline O'Brien, Michael O'Rourke, Alberto Avolio
OBJECTIVE: Relative ease of estimating of Ascending Aortic (AA) pressure non-invasively enables interpretation of age-related pressure waveform changes due to altered pulse wave propagation. AA flow velocity waveforms, measured invasively by ElectroMagnetic (EM) cuff/ catheter, and non-invasively by Cardiac Magnetic Resonance (CMR) also show characteristic aging changes attributable to aortic dilation and subtle impairment of Left Ventricular (LV) function. Conventional Doppler waveforms do not...
September 2016: Journal of Hypertension
https://www.readbyqxmd.com/read/27630580/recognition-of-fibrotic-infarct-density-by-the-pattern-of-local-systolic-diastolic-myocardial-electrical-impedance
#12
Gerard Amorós-Figueras, Esther Jorge, Tomás García-Sánchez, Ramón Bragós, Javier Rosell-Ferrer, Juan Cinca
Myocardial electrical impedance is a biophysical property of the heart that is influenced by the intrinsic structural characteristics of the tissue. Therefore, the structural derangements elicited in a chronic myocardial infarction should cause specific changes in the local systolic-diastolic myocardial impedance, but this is not known. This study aimed to characterize the local changes of systolic-diastolic myocardial impedance in a healed myocardial infarction model. Six pigs were successfully submitted to 150 min of left anterior descending (LAD) coronary artery occlusion followed by reperfusion...
2016: Frontiers in Physiology
https://www.readbyqxmd.com/read/27630010/the-impact-of-the-speed-of-food-intake-on-gastroesophageal-reflux-events-in-obese-female-patients
#13
Serhat Bor, Askin Erdogan, Berna Bayrakci, Esra Yildirim, Rukiye Vardar
Obesity increases the risk of gastroesophageal reflux disease (GERD). The majority of the reflux attacks occur postprandially. The influence of the speed of food intake on gastroesophageal reflux events is unclear in obese patients. To determine the influence of the speed of food intake on intraesophageal reflux events in obese patients with and without GERD. A total of 26 obese female patients were recruited. The patients underwent esophageal manometry to evaluate the upper limit of the lower esophageal sphincter and subsequently placement of a Multichannel intraluminal impedance-pH (MII-pH) catheter...
September 15, 2016: Diseases of the Esophagus: Official Journal of the International Society for Diseases of the Esophagus
https://www.readbyqxmd.com/read/27604397/pepsin-in-saliva-as-a-biomarker-for-oropharyngeal-reflux-compared-with-24-hour-esophageal-impedance-ph-monitoring-in-pediatric-patients
#14
J E Fortunato, R B D'Agostino, M O Lively
BACKGROUND: Pepsin in saliva is a proposed biomarker for oropharyngeal reflux. Pepsin may be prevalent in saliva from subjects with gastro-esophageal reflux and may correlate with proximal reflux by intraluminal impedance/pH monitoring (MII/pH). METHODS: Patients (3 days to 17.6 years, n=90) undergoing 24-hour MII/pH monitoring and asymptomatic controls (2 months to 13.7 years, n=43) were included. Salivary pepsin was determined using a pepsin enzyme-linked immunosorbent assay...
September 7, 2016: Neurogastroenterology and Motility: the Official Journal of the European Gastrointestinal Motility Society
https://www.readbyqxmd.com/read/27589973/parylene-mems-patency-sensor-for-assessment-of-hydrocephalus-shunt-obstruction
#15
Brian J Kim, Willa Jin, Alexander Baldwin, Lawrence Yu, Eisha Christian, Mark D Krieger, J Gordon McComb, Ellis Meng
Neurosurgical ventricular shunts inserted to treat hydrocephalus experience a cumulative failure rate of 80 % over 12 years; obstruction is responsible for most failures with a majority occurring at the proximal catheter. Current diagnosis of shunt malfunction is imprecise and involves neuroimaging studies and shunt tapping, an invasive measurement of intracranial pressure and shunt patency. These patients often present emergently and a delay in care has dire consequences. A microelectromechanical systems (MEMS) patency sensor was developed to enable direct and quantitative tracking of shunt patency in order to detect proximal shunt occlusion prior to the development of clinical symptoms thereby avoiding delays in treatment...
October 2016: Biomedical Microdevices
https://www.readbyqxmd.com/read/27581553/sites-with-small-impedance-decrease-during-catheter-ablation-for-atrial-fibrillation-are-associated-with-recovery-of-pulmonary-vein-conduction
#16
Jason S Chinitz, Sunil Kapur, Chirag Barbhaiya, Saurabh Kumar, Roy John, Laurence M Epstein, Usha Tedrow, William G Stevenson, Gregory F Michaud
OBJECTIVE: To correlate impedance decrease during atrial fibrillation (AF) ablation with lesion durability and PV conduction recovery demonstrated during redo procedures. BACKGROUND: Markers of successful ablation beyond acute conduction block are needed to improve durability of pulmonary vein (PV) isolation (PVI). Local impedance decrease resulting from ablation is a real-time marker of tissue heating and is correlated with lesion creation. METHODS: Impedance changes associated with point-by-point radiofrequency ablation in the PV antra were recorded during 167 consecutive first-time AF ablations...
September 1, 2016: Journal of Cardiovascular Electrophysiology
https://www.readbyqxmd.com/read/27569722/characteristics-of-cavotricuspid-isthmus-ablation-for-atrial-flutter-guided-by-novel-parameters-using-a-contact-force-catheter
#17
Paul A Gould, Cameron Booth, Kieran Dauber, Kevin Ng, Andrew Claughton, Gerald C Kaye
INTRODUCTION: This study sought to investigate specific contact force (CF) parameters to guide cavotricuspid isthmus (CTI) ablation and compare the outcome with a historical control cohort. METHODS AND RESULTS: Patients (30) undergoing CTI ablation were enrolled prospectively in the Study cohort and compared with a retrospective Control cohort of 30 patients. Ablation in the Study cohort was performed using CF parameters >10 g and <40 g and a Force Time Integral (FTI) of 800 ± 10 g...
August 29, 2016: Journal of Cardiovascular Electrophysiology
https://www.readbyqxmd.com/read/27553930/comparison-of-videofluoroscopy-and-impedance-planimetry-for-the-evaluation-of-oesophageal-stenosis-a-retrospective-study
#18
Martina Scharitzer, Johannes Lenglinger, Wolfgang Schima, Michael Weber, Claudia Ringhofer, Peter Pokieser
OBJECTIVES: To compare videofluoroscopy that included a tablet test with impedance planimetry (EndoFLIP(®)) for the evaluation of oesophageal stenosis in patients with dysphagia. METHODS: In 56 patients, videofluoroscopic examinations following the transit of a 14-mm tablet were retrospectively reviewed and correlated with impedance planimetry findings, a catheter-based method using impedance planimetry to display the oesophageal diameter estimates. Additional findings assessed were the occurrence of symptoms during tablet passage and evaluation of oesophageal motility...
August 23, 2016: European Radiology
https://www.readbyqxmd.com/read/27492870/pressure-flow-analysis-for-the-assessment-of-pediatric-oropharyngeal-dysphagia
#19
Lara Ferris, Nathalie Rommel, Sebastian Doeltgen, Ingrid Scholten, Stamatiki Kritas, Rammy Abu-Assi, Lisa McCall, Grace Seiboth, Katie Lowe, David Moore, Jenny Faulks, Taher Omari
OBJECTIVES: To determine which objective pressure-impedance measures of pharyngeal swallowing function correlated with clinically assessed severity of oropharyngeal dysphagia (OPD) symptoms. STUDY DESIGN: Forty-five children with OPD and 34 control children without OPD were recruited and up to 5 liquid bolus swallows were recorded with a solid-state high-resolution manometry with impedance catheter. Individual measures of pharyngeal and upper esophageal sphincter (UES) function and a swallow risk index composite score were derived for each swallow, and averaged data for patients with OPD were compared with those of control children without OPD...
October 2016: Journal of Pediatrics
https://www.readbyqxmd.com/read/27457965/impact-of-mitral-geometry-and-global-afterload-on-improvement-of-mitral-regurgitation-after-trans-catheter-aortic-valve-implantation
#20
Y Tayyareci, R Dworakowski, P Kogoj, J Reiken, C Kenny, P MacCarthy, O Wendler, M J Monaghan
OBJECTIVE: To assess the impact of mitral geometry, left ventricular (LV) remodelling and global LV afterload on mitral regurgitation (MR) after trans-catheter aortic valve implantation (TAVI). METHODS: In this study, 60 patients who underwent TAVI were evaluated by 3D echocardiography at baseline, 1 month and 6 months after procedure. The proportional change in MR following TAVI was determined by examining the percentage change in vena contracta (VC) at 6 months...
September 2016: Echo Research and Practice
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