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Arterial pulse transit time

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https://www.readbyqxmd.com/read/28102355/determining-arterial-wave-transit-time-from-a-single-aortic-pressure-pulse-in-rats-vascular-impulse-response-analysis
#1
Ru-Wen Chang, Chun-Yi Chang, Liang-Chuan Lai, Ming-Shiou Wu, Tai-Horng Young, Yih-Sharng Chen, Chih-Hsien Wang, Kuo-Chu Chang
Arterial wave transit time (τw) in the lower body circulation is an effective biomarker of cardiovascular risk that substantially affects systolic workload imposed on the heart. This study evaluated a method for determining τw from the vascular impulse response on the basis of the measured aortic pressure and an assumed triangular flow (Q(tri)). The base of the unknown Q(tri) was constructed with a duration set equal to ejection time. The timing of the peak triangle was derived using a fourth-order derivative of the pressure waveform...
January 19, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28090301/pulmonary-pulse-wave-transit-time-is-associated-with-right-ventricular-pulmonary-artery-coupling-in-pulmonary-arterial-hypertension
#2
Kurt W Prins, E Kenneth Weir, Stephen L Archer, Jeremy Markowitz, Lauren Rose, Marc Pritzker, Richard Madlon-Kay, Thenappan Thenappan
Pulmonary pulse wave transit time (pPTT), defined as the time for the systolic pressure pulse wave to travel from the pulmonary valve to the pulmonary veins, has been reported to be reduced in pulmonary arterial hypertension (PAH); however, the underlying mechanism of reduced pPTT is unknown. Here, we investigate the hypothesis that abbreviated pPTT in PAH results from impaired right ventricular-pulmonary artery (RV-PA) coupling. We quantified pPTT using pulsed-wave Doppler ultrasound from 10 healthy age- and sex-matched controls and 36 patients with PAH...
December 2016: Pulmonary Circulation
https://www.readbyqxmd.com/read/28060961/pilot-study-estimation-of-stroke-volume-and-cardiac-output-from-pulse-wave-velocity
#3
Yurie Obata, Maki Mizogami, Daniel Nyhan, Dan E Berkowitz, Jochen Steppan, Viachaslau Barodka
BACKGROUND: Transesophageal echocardiography (TEE) is increasingly replacing thermodilution pulmonary artery catheters to assess hemodynamics in patients at high risk for cardiovascular morbidity. However, one of the drawbacks of TEE compared to pulmonary artery catheters is the inability to measure real time stroke volume (SV) and cardiac output (CO) continuously. The aim of the present proof of concept study was to validate a novel method of SV estimation, based on pulse wave velocity (PWV) in patients undergoing cardiac surgery...
2017: PloS One
https://www.readbyqxmd.com/read/28046980/we-fg-206-05-new-arterial-spin-labeling-method-for-simultaneous-estimation-of-arterial-cerebral-blood-volume-cerebral-blood-flow-and-arterial-transit-time
#4
M Johnston, H Liu, C Whitlow, Y Jung
PURPOSE: To demonstrate the feasibility of a novel Arterial Spin Labeling (ASL) method for simultaneously measuring cerebral blood flow (CBF), arterial transit time (ATT), and arterial cerebral blood volume (aCBV) without the use of a contrast agent. METHODS: A series of multi-TI ASL images were acquired from one healthy subject on a 3T Siemens Skyra, with the following parameters: PCASL labeling with variable TI [300, 400, 500, 600, 700, 800, 900, 1000, 1500, 2000, 2500, 3000, 3500, 4000] ms, labeling bolus 1400 ms when TI allows, otherwise 100 ms less than TI, TR was minimized for each TI, two sinc shaped pre-saturation pulses were applied in the imaging plane immediately before 2D EPI acquisition...
June 2016: Medical Physics
https://www.readbyqxmd.com/read/27976741/weighing-scale-based-pulse-transit-time-is-a-superior-marker-of-blood-pressure-than-conventional-pulse-arrival-time
#5
Stephanie L-O Martin, Andrew M Carek, Chang-Sei Kim, Hazar Ashouri, Omer T Inan, Jin-Oh Hahn, Ramakrishna Mukkamala
Pulse transit time (PTT) is being widely pursued for cuff-less blood pressure (BP) monitoring. Most efforts have employed the time delay between ECG and finger photoplethysmography (PPG) waveforms as a convenient surrogate of PTT. However, these conventional pulse arrival time (PAT) measurements include the pre-ejection period (PEP) and the time delay through small, muscular arteries and may thus be an unreliable marker of BP. We assessed a bathroom weighing scale-like system for convenient measurement of ballistocardiography and foot PPG waveforms - and thus PTT through larger, more elastic arteries - in terms of its ability to improve tracking of BP in individual subjects...
December 15, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27923785/genetic-determination-of-the-vascular-reactions-in-humans-in-response-to-the-diving-reflex
#6
Tatiana I Baranova, Dmitrii N Berlov, Oleg S Glotov, Ekaterina A Korf, Alexey D Minigalin, Alla V Mitrofanova, Ildus I Ahmetov, Andrey S Glotov
The purpose of this study was to investigate the genetic mechanisms of the defense vascular reactions in response to the diving reflex in humans with polymorphisms in the genes ADBR2, ACE, AGTR1, BDKRB2, and REN. We hypothesized that protective vascular reactions, in response to the diving reflex, are genetically determined and are distinguished in humans with gene polymorphisms of the renin-angiotensin and kinin-bradykinin system. A total of 80 subjects (19±1.4 years) participated in the study. The intensity of the vascular response was estimated using photopletismogram...
December 6, 2016: American Journal of Physiology. Heart and Circulatory Physiology
https://www.readbyqxmd.com/read/27900333/the-effects-of-hemodynamic-changes-on-pulse-wave-velocity-in-cardiothoracic-surgical-patients
#7
Yurie Obata, Maki Mizogami, Sarabdeep Singh, Daniel Nyhan, Dan E Berkowitz, Jochen Steppan, Viachaslau Barodka
The effect of blood pressure on pulse wave velocity (PWV) is well established. However, PWV variability with acute hemodynamic changes has not been examined in the clinical setting. The aim of the present study is to investigate the effect of hemodynamic changes on PWV in patients who undergo cardiothoracic surgery. Using data from 25 patients, we determined blood pressure (BP), heart rate (HR), and the left ventricular outflow tract (LVOT) velocity-time integral. By superimposing the radial arterial waveform on the continuous wave Doppler waveform of the LVOT, obtained by transesophageal echo, we were able to determine pulse transit time and to calculate PWV, stroke volume (SV), cardiac output (CO), and systemic vascular resistance (SVR)...
2016: BioMed Research International
https://www.readbyqxmd.com/read/27867733/multi-wavelength-photoplethysmography-method-for-skin-arterial-pulse-extraction
#8
Jing Liu, Bryan Ping-Yen Yan, Wen-Xuan Dai, Xiao-Rong Ding, Yuan-Ting Zhang, Ni Zhao
In this work, we present a multi-wavelength (MW) PPG method exploiting the wavelength dependence of light penetration in skin tissue to provide depth resolution of skin blood pulsation. The MW PPG system requires two to three light sources in different wavelengths and extracts the arterial blood pulsation through a multi-wavelength multi-layer light-skin interaction model, which removes the capillary pulsation (determined from the short-wavelength PPG signal) from the long-wavelength PPG signal using absorption weighting factors that are quasi-analytically calibrated...
October 1, 2016: Biomedical Optics Express
https://www.readbyqxmd.com/read/27843548/assessment-of-proximal-pulmonary-arterial-stiffness-using-magnetic-resonance-imaging-effects-of-technique-age-and-exercise
#9
Jonathan R Weir-McCall, Anu Kamalasanan, Deidre B Cassidy, Allan D Struthers, Brian J Lipworth, J Graeme Houston
INTRODUCTION: To compare the reproducibility of pulmonary pulse wave velocity (PWV) techniques, and the effects of age and exercise on these. METHODS: 10 young healthy volunteers (YHV) and 20 older healthy volunteers (OHV) with no cardiac or lung condition were recruited. High temporal resolution phase contrast sequences were performed through the main pulmonary arteries (MPAs), right pulmonary arteries (RPAs) and left pulmonary arteries (LPAs), while high spatial resolution sequences were obtained through the MPA...
2016: BMJ Open Respiratory Research
https://www.readbyqxmd.com/read/27802696/features-of-the-non-contact-carotid-pressure-waveform-cardiac-and-vascular-dynamics-during-rebreathing
#10
S Casaccia, E J Sirevaag, E J Richter, J A O'Sullivan, L Scalise, J W Rohrbaugh
This report amplifies and extends prior descriptions of the use of laser Doppler vibrometry (LDV) as a method for assessing cardiovascular activity, on a non-contact basis. A rebreathing task (n = 35 healthy individuals) was used to elicit multiple effects associated with changes in autonomic drive as well as blood gases including hypercapnia. The LDV pulse was obtained from two sites overlying the carotid artery, separated by 40 mm. A robust pulse signal was obtained from both sites, in accord with the well-described changes in carotid diameter over the blood pressure cycle...
October 2016: Review of Scientific Instruments
https://www.readbyqxmd.com/read/27755938/arterial-spin-labeling-perfusion-of-the-brain-emerging-clinical-applications
#11
Sven Haller, Greg Zaharchuk, David L Thomas, Karl-Olof Lovblad, Frederik Barkhof, Xavier Golay
Arterial spin labeling (ASL) is a magnetic resonance (MR) imaging technique used to assess cerebral blood flow noninvasively by magnetically labeling inflowing blood. In this article, the main labeling techniques, notably pulsed and pseudocontinuous ASL, as well as emerging clinical applications will be reviewed. In dementia, the pattern of hypoperfusion on ASL images closely matches the established patterns of hypometabolism on fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET) images due to the close coupling of perfusion and metabolism in the brain...
November 2016: Radiology
https://www.readbyqxmd.com/read/27614541/echocardiographic-assessment-of-aortic-pulse-wave-velocity-validation-against-invasive-pressure-measurements
#12
Grzegorz Styczynski, Adam Rdzanek, Arkadiusz Pietrasik, Janusz Kochman, Zenon Huczek, Piotr Sobieraj, Zbigniew Gaciong, Cezary Szmigielski
BACKGROUND: Aortic pulse-wave velocity (PWV) is a measure of aortic stiffness that has a prognostic role in various diseases and in the general population. A number of methods are used to measure PWV, including Doppler ultrasound. Although echocardiography has been used for PWV measurement, to the authors' knowledge, it has never been tested against an invasive reference method at the same time point. Therefore, the aim of this study was to compare prospectively an echocardiographic PWV measurement, called echo-PWV, with an invasive study...
November 2016: Journal of the American Society of Echocardiography
https://www.readbyqxmd.com/read/27508593/-op-lb03-04-first-in-man-measurement-of-arterial-stiffness-using-a-connected-bathroom-scale-calibration-against-sphygmocor
#13
H Khettab, D Campo, R Yu, N Buard, P Boutouyrie
OBJECTIVE: Measurement of arterial stiffness (AS) is still hampered by the technical skill necessary to obtain reliable measurements. It is generally considered that AS is not prone to self-measurement. We developed a non-invasive technique to assess AS from a connected bathroom scale, based on ballistocardiography (BCG) and impedance plethysmography (IPG).(Figure is included in full-text article.) DESIGN AND METHOD: :: We included 76 healthy subjects and 35 essential hypertensive, 50% women...
September 2016: Journal of Hypertension
https://www.readbyqxmd.com/read/27508577/-op-8d-03-measurement-of-arterial-stiffness-by-ultrafast-echo-comparison-with-echotracking-in-normotensive-subjects-and-hypertensive-patients
#14
L Marais, M Pernot, H Khettab, M Tanter, E Messas, M Zidi, S Laurent, P Boutouyrie
OBJECTIVE: The question whether arterial stiffness in hypertension is increased solely because of increased arterial pressure is not solved. Because measurement of arterial stiffness is highly dependent on measurement of blood pressure (BP), the development of methods independent of BP is necessary for clarifying this question. Ultrafast echography (UFE, Supersonic Imagine, Aix en Provence, France) makes use of very fast sampling rate (up to 10 kHz), so transient events such as pressure wave arrival can be tracked...
September 2016: Journal of Hypertension
https://www.readbyqxmd.com/read/27496168/arterial-path-length-for-arterial-stiffness-methodological-consideration
#15
Jun Sugawara, Koichiro Hayashi, Hirofumi Tanaka
BACKGROUND: Carotid-femoral pulse wave velocity (cfPWV) is the most established measure of central arterial stiffness and is calculated by dividing the distance travelled by the pulse wave by the pulse transit time. However, there is no universally accepted standardized measurement of pulse travel distance for cfPWV. This study sought to assess validity and convertibility of 2 most frequently used travel distance estimations, and create the simple and useful conversion equation to unify cfPWV values obtained with different methodologies for pulse travel distance...
August 5, 2016: American Journal of Hypertension
https://www.readbyqxmd.com/read/27479981/characteristic-ratio-independent-arterial-stiffness-based-blood-pressure-estimation
#16
Seddigheh Baktash, Mohamad Forouzanfar, Izmail Batkin, Miodrag Bolic, Voicu Groza, Saif Ahmad, Hilmi Dajani
Non-invasive blood pressure (BP) measurement is an important tool for managing hypertension and cardiovascular disease. However, automated non-invasive BP measurement devices, which are usually based on the oscillometric method, do not always provide accurate estimation of BP. It has been found that change in arterial stiffness (AS) is an underlying mechanism of disagreement between an oscillometric BP monitor and a sphygmomanometer. This problem is addressed by incorporating parameters related to AS in the algorithm for BP measurement...
July 27, 2016: IEEE Journal of Biomedical and Health Informatics
https://www.readbyqxmd.com/read/27434046/correction-arterial-transit-time-mapping-obtained-by-pulsed-continuous-3d-asl-imaging-with-multiple-post-label-delay-acquisitions-comparative-study-with-pet-cbf-in-patients-with-chronic-occlusive-cerebrovascular-disease
#17
https://www.readbyqxmd.com/read/27387199/required-temporal-resolution-for-accurate-thoracic-aortic-pulse-wave-velocity-measurements-by-phase-contrast-magnetic-resonance-imaging-and-comparison-with-clinical-standard-applanation-tonometry
#18
Karolina Dorniak, Einar Heiberg, Marcin Hellmann, Dorota Rawicz-Zegrzda, Maria Wesierska, Rafal Galaska, Agnieszka Sabisz, Edyta Szurowska, Maria Dudziak, Erik Hedström
BACKGROUND: Pulse wave velocity (PWV) is a biomarker for arterial stiffness, clinically assessed by applanation tonometry (AT). Increased use of phase-contrast cardiac magnetic resonance (CMR) imaging allows for PWV assessment with minor routine protocol additions. The aims were to investigate the acquired temporal resolution needed for accurate and precise measurements of CMR-PWV, and develop a tool for CMR-PWV measurements. METHODS: Computer phantoms were generated for PWV = 2-20 m/s based on human CMR-PWV data...
2016: BMC Cardiovascular Disorders
https://www.readbyqxmd.com/read/27337707/blood-pressure-estimation-using-pulse-transit-time-from-bioimpedance-and-continuous-wave-radar
#19
Dilpreet Buxi, Jean-Michel Redoute, Mehmet Rasit Yuce
OBJECTIVE: We have developed and tested a new architecture for pulse transit time (PTT) estimation at the central arteries using electrical bioimpedance, electrocardiogram and continuous wave radar to estimate cuffless blood pressure. METHODS: A transmitter and receiver antenna is placed at the sternum to acquire the arterial pulsation at the aortic arch. A four-electrode arrangement across the shoulders acquires arterial pulse across the carotid and subclavian arteries from bioimpedance as well as a bipolar lead I electrocardiogram...
June 20, 2016: IEEE Transactions on Bio-medical Engineering
https://www.readbyqxmd.com/read/27275779/arterial-transit-time-mapping-obtained-by-pulsed-continuous-3d-asl-imaging-with-multiple-post-label-delay-acquisitions-comparative-study-with-pet-cbf-in-patients-with-chronic-occlusive-cerebrovascular-disease
#20
Tetsuya Tsujikawa, Hirohiko Kimura, Tsuyoshi Matsuda, Yasuhiro Fujiwara, Makoto Isozaki, Ken-Ichiro Kikuta, Hidehiko Okazawa
Arterial transit time (ATT) is most crucial for measuring absolute cerebral blood flow (CBF) by arterial spin labeling (ASL), a noninvasive magnetic resonance (MR) perfusion assessment technique, in patients with chronic occlusive cerebrovascular disease. We validated ASL-CBF and ASL-ATT maps calculated by pulsed continuous ASL (pCASL) with multiple post-label delay acquisitions in patients with occlusive cerebrovascular disease. Fifteen patients underwent MR scans, including pCASL, and positron emission tomography (PET) scans with 15O-water to obtain PET-CBF...
2016: PloS One
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