Kliknij ten link, aby zobaczyć inne rodzaje publikacji na ten temat: Carotid Arterial Pulse Pressure Waveform (CAPPW).

Artykuły w czasopismach na temat „Carotid Arterial Pulse Pressure Waveform (CAPPW)”

Utwórz poprawne odniesienie w stylach APA, MLA, Chicago, Harvard i wielu innych

Wybierz rodzaj źródła:

Sprawdź 24 najlepszych artykułów w czasopismach naukowych na temat „Carotid Arterial Pulse Pressure Waveform (CAPPW)”.

Przycisk „Dodaj do bibliografii” jest dostępny obok każdej pracy w bibliografii. Użyj go – a my automatycznie utworzymy odniesienie bibliograficzne do wybranej pracy w stylu cytowania, którego potrzebujesz: APA, MLA, Harvard, Chicago, Vancouver itp.

Możesz również pobrać pełny tekst publikacji naukowej w formacie „.pdf” i przeczytać adnotację do pracy online, jeśli odpowiednie parametry są dostępne w metadanych.

Przeglądaj artykuły w czasopismach z różnych dziedzin i twórz odpowiednie bibliografie.

1

Liu, Chengyu, Tao Zhuang, Lina Zhao, Faliang Chang, Changchun Liu, Shoushui Wei, Qiqiang Li i Dingchang Zheng. "Modelling Arterial Pressure Waveforms Using Gaussian Functions and Two-Stage Particle Swarm Optimizer". BioMed Research International 2014 (2014): 1–10. http://dx.doi.org/10.1155/2014/923260.

Pełny tekst źródła
Streszczenie:
Changes of arterial pressure waveform characteristics have been accepted as risk indicators of cardiovascular diseases. Waveform modelling using Gaussian functions has been used to decompose arterial pressure pulses into different numbers of subwaves and hence quantify waveform characteristics. However, the fitting accuracy and computation efficiency of current modelling approaches need to be improved. This study aimed to develop a novel two-stage particle swarm optimizer (TSPSO) to determine optimal parameters of Gaussian functions. The evaluation was performed on carotid and radial artery pressure waveforms (CAPW and RAPW) which were simultaneously recorded from twenty normal volunteers. The fitting accuracy and calculation efficiency of our TSPSO were compared with three published optimization methods: the Nelder-Mead, the modified PSO (MPSO), and the dynamic multiswarm particle swarm optimizer (DMS-PSO). The results showed that TSPSO achieved the best fitting accuracy with a mean absolute error (MAE) of 1.1% for CAPW and 1.0% for RAPW, in comparison with 4.2% and 4.1% for Nelder-Mead, 2.0% and 1.9% for MPSO, and 1.2% and 1.1% for DMS-PSO. In addition, to achieve target MAE of 2.0%, the computation time of TSPSO was only 1.5 s, which was only 20% and 30% of that for MPSO and DMS-PSO, respectively.
Style APA, Harvard, Vancouver, ISO itp.
2

Salvi, Paolo, Filippo Valbusa, Anna Kearney-Schwartz, Carlos Labat, Andrea Grillo, Gianfranco Parati i Athanase Benetos. "Non-Invasive Assessment of Arterial Stiffness: Pulse Wave Velocity, Pulse Wave Analysis and Carotid Cross-Sectional Distensibility: Comparison between Methods". Journal of Clinical Medicine 11, nr 8 (15.04.2022): 2225. http://dx.doi.org/10.3390/jcm11082225.

Pełny tekst źródła
Streszczenie:
Background: The stiffening of large elastic arteries is currently estimated in research and clinical practice by propagative and non-propagative models, as well as parameters derived from aortic pulse waveform analysis. Methods: Common carotid compliance and distensibility were measured by simultaneously recording the diameter and pressure changes during the cardiac cycle. The aortic and upper arm arterial distensibility was estimated by measuring carotid–femoral and carotid–radial pulse wave velocity (PWV), respectively. The augmentation index and blood pressure amplification were derived from the analysis of central pulse waveforms, recorded by applanation tonometry directly from the common carotid artery. Results: 75 volunteers were enrolled in this study (50 females, average age 53.5 years). A significant inverse correlation was found between carotid distensibility and carotid–femoral PWV (r = −0.75; p < 0.001), augmentation index (r = −0.63; p < 0.001) and central pulse pressure (r = −0.59; p < 0.001). A strong correlation was found also between the total slope of the diameter/pressure rate carotid curves and aortic distensibility, quantified from the inverse of the square of carotid–femoral PWV (r = 0.67). No correlation was found between carotid distensibility and carotid–radial PWV. Conclusions: This study showed a close correlation between carotid–femoral PWV, evaluating aortic stiffness by using the propagative method, and local carotid cross-sectional distensibility.
Style APA, Harvard, Vancouver, ISO itp.
3

Shibata, Shigeki, i Benjamin D. Levine. "Biological aortic age derived from the arterial pressure waveform". Journal of Applied Physiology 110, nr 4 (kwiecień 2011): 981–87. http://dx.doi.org/10.1152/japplphysiol.01261.2010.

Pełny tekst źródła
Streszczenie:
Indexes for arterial stiffness are, by their nature, influenced by the ambient blood pressure due to the curvilinear nature of arterial compliance. We developed a new concept of the “Modelflow aortic age,” which is, theoretically, not influenced by the ambient blood pressure and provides an easily understood context (biological vs. chronological age) for measures of arterial stiffness. The purpose of the present study was to validate this pressure-independent index for aortic stiffness in humans. Twelve sedentary elderly (65–77 yr), 11 Masters athletes (65–73 yr), and 12 sedentary young individuals (20–42 yr) were studied. Modelflow aortic ages were comparable with chronological ages in both sedentary groups, indicating that healthy sedentary individuals have age-appropriate aortas. In contrast, Masters athletes showed younger Modelflow aortic ages than their chronological ages. The coefficient of variation of sedentary subjects was three times smaller with the Modelflow aortic age (21%) than with other indexes, such as static systemic arterial stiffness (61%), central pulse wave velocity (61%), or carotid β-stiffness index (58%). The typical error was very small and two times smaller in the Modelflow aortic age (<7%) than in static systemic arterial stiffness (>13%) during cardiac unloading by lower body negative pressure. The Modelflow aortic age can more precisely and reliably estimate aortic stiffening with aging and modifiers, such as life-long exercise training compared with the pressure-dependent index of static systemic arterial stiffness, and provides a physiologically relevant and clinically compelling context for such measurements.
Style APA, Harvard, Vancouver, ISO itp.
4

van Houwelingen, Marc J., Daphne Merkus, Jan Hofland, Jan Bakker, Robert Tenbrinck, Maaike te Lintel Hekkert, Geert van Dijk, Arnold P. G. Hoeks i Dirk J. Duncker. "A novel approach to assess hemorrhagic shock severity using the arterially determined left ventricular isovolumic contraction period". American Journal of Physiology-Heart and Circulatory Physiology 305, nr 12 (15.12.2013): H1790—H1797. http://dx.doi.org/10.1152/ajpheart.00504.2013.

Pełny tekst źródła
Streszczenie:
Recently, the ventilatory variation in pre-ejection period (ΔPEP) was found to be useful in the prediction of fluid-responsiveness of patients in shock. In the present study we investigated the behavior of the ventilation-induced variations in the systolic timing intervals in response to a graded hemorrhage protocol. The timing intervals studied included the ventilatory variation in ventricular electromechanical delay (ΔEMD), isovolumic contraction period (determined from the arterial pressure waveform, ΔAIC), pulse travel time (ΔPTT), and ΔPEP. ΔAIC and ΔPEP were evaluated in the aorta and carotid artery (annotated by subscripts Ao and CA) and were compared with the responses of pulse pressure variation (ΔPPAo) and stroke volume variation (ΔSV). The graded hemorrhage protocol, followed by resuscitation using norepinephrine and autologous blood transfusion, was performed in eight anesthetized Yorkshire X Landrace swine. ΔAICAo, ΔAICCA, ΔPEPAo, ΔPEPCA, ΔPPAo, ΔPPCA, and ΔSV showed significant increases during the graded hemorrhage and significant decreases during the subsequent resuscitation. ΔAICAo, ΔAICCA, ΔPEPAo, and ΔPEPCA all correlated well with ΔPPAo and ΔSV (all r ≥ 0.8, all P < 0.001). ΔEMD and ΔPTT did not significantly change throughout the protocol. In contrast with ΔPEPAo, which was significantly higher than ΔPEPCA ( P < 0.01), ΔAICAo was not different from ΔAICCA. In conclusion, ventilation-induced preload variation principally affects the arterially determined isovolumic contraction period (AIC). Moreover, ΔAIC can be determined solely from the arterial pressure waveform, whereas ΔPEP also requires ECG measurement. Importantly, ΔAIC determined from either the carotid or aortic pressure waveform are interchangeable, suggesting that, in contrast with ΔPEP, ΔAIC may be site independent.
Style APA, Harvard, Vancouver, ISO itp.
5

Edwards, David G., Matthew S. Roy i Raju Y. Prasad. "Wave reflection augments central systolic and pulse pressures during facial cooling". American Journal of Physiology-Heart and Circulatory Physiology 294, nr 6 (czerwiec 2008): H2535—H2539. http://dx.doi.org/10.1152/ajpheart.01369.2007.

Pełny tekst źródła
Streszczenie:
Cardiovascular events are more common in the winter months, possibly because of hemodynamic alterations in response to cold exposure. The purpose of this study was to determine the effect of acute facial cooling on central aortic pressure, arterial stiffness, and wave reflection. Twelve healthy subjects (age 23 ± 3 yr; 6 men, 6 women) underwent supine measurements of carotid-femoral pulse wave velocity (PWV), brachial artery blood pressure, and central aortic pressure (via the synthesis of a central aortic pressure waveform by radial artery applanation tonometry and generalized transfer function) during a control trial (supine rest) and a facial cooling trial (0°C gel pack). Aortic augmentation index (AI), an index of wave reflection, was calculated from the aortic pressure waveform. Measurements were made at baseline, 2 min, and 7 min during each trial. Facial cooling increased ( P < 0.05) peripheral and central diastolic and systolic pressures. Central systolic pressure increased more than peripheral systolic pressure (22 ± 3 vs. 15 ± 2 mmHg; P < 0.05), resulting in decreased pulse pressure amplification ratio. Facial cooling resulted in a robust increase in AI and a modest increase in PWV (AI: −1.4 ± 3.8 vs. 21.2 ± 3.0 and 19.9 ± 3.6%; PWV: 5.6 ± 0.2 vs. 6.5 ± 0.3 and 6.2 ± 0.2 m/s; P < 0.05). Change in mean arterial pressure but not PWV predicted the change in AI, suggesting that facial cooling may increase AI independent of aortic PWV. Facial cooling and the resulting peripheral vasoconstriction are associated with an increase in wave reflection and augmentation of central systolic pressure, potentially explaining ischemia and cardiovascular events in the cold.
Style APA, Harvard, Vancouver, ISO itp.
6

Holewijn, Suzanne, Jenske J. M. Vermeulen, Majorie van Helvert, Lennart van de Velde i Michel M. P. J. Reijnen. "Changes in Noninvasive Arterial Stiffness and Central Blood Pressure After Endovascular Abdominal Aneurysm Repair". Journal of Endovascular Therapy 28, nr 3 (9.04.2021): 434–41. http://dx.doi.org/10.1177/15266028211007460.

Pełny tekst źródła
Streszczenie:
Purpose: To evaluate the impact of elective endovascular aneurysm repair (EVAR) on the carotid-femoral pulse wave velocity (cfPWV) and central pressure waveform, through 1-year follow-up. Materials and Methods: A tonometric device was used to measure cfPWV and estimate the central pressure waveform in 20 patients with an infrarenal abdominal aortic aneurysm scheduled for elective EVAR. The evaluated central hemodynamic parameters included the central pressures, the augmentation index (AIx), and the subendocardial viability ratio (SEVR). AIx quantifies the contribution of reflected wave to the central systolic pressure, whereas SEVR describes the myocardial perfusion relative to the cardiac workload. Measurements were performed before EVAR, at discharge, and 6 weeks and 1 year after EVAR. Results: CfPWV was increased at discharge (12.4±0.4 vs 11.3±0.5 m/s at baseline; p=0.005) and remained elevated over the course of 1-year follow-up (6 weeks: cfPWV = 12.2±0.5 m/s; 1 year: cfPWV = 12.2±0.7 m/s, p<0.05). After an initial drop in systolic central pressure at discharge, all the central pressures increased thereafter up to 1 year, without significant differences compared with baseline. The same was observed for the AIx and SEVR. Conclusion: Endovascular aortic aneurysm repair caused an increase in pulse wave velocity compared with baseline, which remained elevated through 1 year follow-up, which may be related to an increased cardiovascular risk. However, no differences in central pressure, augmentation index, and subendocardial viability ration were observed during follow-up.
Style APA, Harvard, Vancouver, ISO itp.
7

Reesink, Koen D., Evelien Hermeling, M. Christianne Hoeberigs, Robert S. Reneman i Arnold P. G. Hoeks. "Carotid artery pulse wave time characteristics to quantify ventriculoarterial responses to orthostatic challenge". Journal of Applied Physiology 102, nr 6 (czerwiec 2007): 2128–34. http://dx.doi.org/10.1152/japplphysiol.01206.2006.

Pełny tekst źródła
Streszczenie:
Central blood pressure waveforms contain specific features related to cardiac and arterial function. We investigated posture-related changes in ventriculoarterial hemodynamics by means of carotid artery (CA) pulse wave analysis. ECG, brachial cuff pressure, and common CA diameter waveforms (by M-mode ultrasound) were obtained in 21 healthy volunteers (19–30 yr of age, 10 men and 11 women) in supine and sitting positions. Pulse wave analysis was based on a timing extraction algorithm that automatically detects acceleration maxima in the second derivative of the CA pulse waveform. The algorithm enabled determination of isovolumic contraction period (ICP) and ejection period (EP): ICP = 43 ± 8 (SD) ms (4-ms precision), and EP = 302 ± 16 (SD) ms (5-ms precision). Compared with the supine position, in the sitting position diastolic blood pressure (DBP) increased by 7 ± 4 mmHg ( P < 0.001) and R-R interval decreased by 49 ± 82 ms ( P = 0.013), reflecting normal baroreflex response, whereas EP decreased to 267 ± 19 ms ( P < 0.001). Shortening of EP was significantly correlated to earlier arrival of the lower body peripheral reflection wave ( r2 = 0.46, P < 0.001). ICP increased by 7 ± 7 ms ( P < 0.001), the ICP-to-EP ratio increased from 14 ± 3% (supine) to 19 ± 3% ( P < 0.001) and the DBP-to-ICP ratio decreased by 7% ( P = 0.023). These results suggest that orthostasis decreases left ventricular output as a result of arterial wave reflections and, presumably, reduced cardiac preload. We conclude that CA ultrasound and pulse wave analysis enable noninvasive quantification of ventriculoarterial responses to changes in posture.
Style APA, Harvard, Vancouver, ISO itp.
8

Yildiz, Mustafa. "Arterial Distensibility in Chronic Inflammatory Rheumatic Disorders". Open Cardiovascular Medicine Journal 4, nr 1 (23.02.2010): 83–88. http://dx.doi.org/10.2174/1874192401004010083.

Pełny tekst źródła
Streszczenie:
The pulse wave velocity (PWV), as an indicator of arterial distensibility, may play an important role in the stratification of patients based on the cardiovascular risk. PWV inversely correlates with arterial distensibility and relative arterial compliance. Decreased arterial distensibility alters arterial blood pressure and flow dynamics, and disturbes coronary perfusion. Systemic immune and inflammatory diseases, such as rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) are associated with increased morbidity and mortality, predominantly due to adverse cardiovascular events. Systemic inflammation in these disorders may alter arterial compliance and arterial distensibility and, through this effect, lead to accelerated atherosclerosis. We have demonstrated an increase in the carotid-femoral (aortic) PWV that is a technique in which large artery elasticity is assessed from analysis of the peripheral arterial waveform, in patients with chronic inflammatory conditions such as RA, SLE, familial Mediterranean fever (FMF), Wegener’s granulomatosis (WG), sarcoidosis, psoriasis and psoriatic arthritis except Behçet’s disease (BD). In this review, the issue of arterial stiffness in RA, SLE, as well as WG, psoriasis, FMF, BD, sarcoidosis, systemic sclerosis (SS) and Takayasu's arteritis (TA) is overviewed.
Style APA, Harvard, Vancouver, ISO itp.
9

Paré, Mathilde, Rémi Goupil, Catherine Fortier, Fabrice Mac-Way, François Madore, Bernhard Hametner, Siegfried Wassertheurer, Martin G. Schultz, James E. Sharman i Mohsen Agharazii. "Increased Excess Pressure After Creation of an Arteriovenous Fistula in End-Stage Renal Disease". American Journal of Hypertension 35, nr 2 (16.10.2021): 149–55. http://dx.doi.org/10.1093/ajh/hpab161.

Pełny tekst źródła
Streszczenie:
ABSTRACT BACKGROUND Reservoir-wave analysis (RWA) separates the arterial waveform into reservoir and excess pressure (XSP) components, where XSP is analogous to flow and related to left ventricular workload. RWA provides more detailed information about the arterial tree than traditional blood pressure (BP) parameters. In end-stage renal disease (ESRD), we have previously shown that XSP is associated with increased mortality and is higher in patients with arteriovenous fistula (AVF). In this study, we examined whether XSP increases after creation of an AVF in ESRD. METHODS Before and after a mean of 3.9 ± 1.2 months following creation of AVF, carotid pressure waves were recorded using arterial tonometry. XSP and its integral (XSPI) were derived using RWA through pressure wave analysis alone. Aortic stiffness was assessed by carotid–femoral pulse wave velocity (CF-PWV). RESURLTS In 38 patients (63% male, age 59 ± 15 years), after AVF creation, brachial diastolic BP decreased (79 ± 10 vs. 72 ± 12 mm Hg, P = 0.002), but the reduction in systolic BP, was not statistically significant (133 ± 20 vs. 127 ± 26 mm Hg, P = 0.137). However, carotid XSP (14 [12–19] to 17 [12–22] mm Hg, P = 0.031) and XSPI increased significantly (275 [212–335] to 334 [241–439] kPa∙s, P = 0.015), despite a reduction in CF-PWV (13 ± 3.6 vs. 12 ± 3.5 m/s, P = 0.025). CONCLUSIONS Creation of an AVF resulted in increased XSP in this population, despite improvement in diastolic BP and aortic stiffness. These findings underline the complex hemodynamic impact of AVF on the cardiovascular system.
Style APA, Harvard, Vancouver, ISO itp.
10

Tomasova, Lenka, Marian Grman, Anton Misak, Lucia Kurakova, Elena Ondriasova i Karol Ondrias. "Cardiovascular “Patterns” of H2S and SSNO−-Mix Evaluated from 35 Rat Hemodynamic Parameters". Biomolecules 11, nr 2 (16.02.2021): 293. http://dx.doi.org/10.3390/biom11020293.

Pełny tekst źródła
Streszczenie:
This work is based on the hypothesis that it is possible to characterize the cardiovascular system just from the detailed shape of the arterial pulse waveform (APW). Since H2S, NO donor S-nitrosoglutathione (GSNO) and their H2S/GSNO products (SSNO−-mix) have numerous biological actions, we aimed to compare their effects on APW and to find characteristic “patterns” of their actions. The right jugular vein of anesthetized rats was cannulated for i.v. administration of the compounds. The left carotid artery was cannulated to detect APW. From APW, 35 hemodynamic parameters (HPs) were evaluated. H2S transiently influenced all 35 HPs and from their cross-relationships to systolic blood pressure “patterns” and direct/indirect signaling pathways of the H2S effect were proposed. The observed “patterns” were mostly different from the published ones for GSNO. Effect of SSNO−-mix (≤32 nmol kg−1) on blood pressure in the presence or absence of a nitric oxide synthase inhibitor (L-NAME) was minor in comparison to GSNO, suggesting that the formation of SSNO−-mix in blood diminished the hemodynamic effect of NO. The observed time-dependent changes of 35 HPs, their cross-relationships and non-hysteresis/hysteresis profiles may serve as “patterns” for the conditions of a transient decrease/increase of blood pressure caused by H2S.
Style APA, Harvard, Vancouver, ISO itp.
11

Balis, Peter, Andrea Berenyiova, Anton Misak, Marian Grman, Zuzana Rostakova, Iveta Waczulikova, Sona Cacanyiova, Enrique Domínguez-Álvarez i Karol Ondrias. "The Phthalic Selenoanhydride Decreases Rat Blood Pressure and Tension of Isolated Mesenteric, Femoral and Renal Arteries". Molecules 28, nr 12 (17.06.2023): 4826. http://dx.doi.org/10.3390/molecules28124826.

Pełny tekst źródła
Streszczenie:
Phthalic selenoanhydride (R-Se) solved in physiological buffer releases various reactive selenium species including H2Se. It is a potential compound for Se supplementation which exerts several biological effects, but its effect on the cardiovascular system is still unknown. Therefore, herein we aimed to study how R-Se affects rat hemodynamic parameters and vasoactive properties in isolated arteries. The right jugular vein of anesthetized Wistar male rats was cannulated for IV administration of R-Se. The arterial pulse waveform (APW) was detected by cannulation of the left carotid artery, enabling the evaluation of 35 parameters. R-Se (1–2 µmol kg−1), but not phthalic anhydride or phthalic thioanhydride, transiently modulated most of the APW parameters including a decrease in systolic and diastolic blood pressure, heart rate, dP/dtmax relative level, or anacrotic/dicrotic notches, whereas systolic area, dP/dtmin delay, dP/dtd delay, anacrotic notch relative level or its delay increased. R-Se (~10–100 µmol L−1) significantly decreased the tension of precontracted mesenteric, femoral, and renal arteries, whereas it showed a moderate vasorelaxation effect on thoracic aorta isolated from normotensive Wistar rats. The results imply that R-Se acts on vascular smooth muscle cells, which might underlie the effects of R-Se on the rat hemodynamic parameters.
Style APA, Harvard, Vancouver, ISO itp.
12

Misak, Anton, Lucia Kurakova, Andrea Berenyiova, Lenka Tomasova, Marian Grman, Sona Cacanyiova i Karol Ondrias. "Patterns and Direct/Indirect Signaling Pathways in Cardiovascular System in the Condition of Transient Increase of NO". BioMed Research International 2020 (28.05.2020): 1–16. http://dx.doi.org/10.1155/2020/6578213.

Pełny tekst źródła
Streszczenie:
Aim. To study “patterns” and connections of signaling pathways derived from the rat arterial pulse waveform (APW) under the condition of transient NO increase. Methods and Results. The right jugular vein of anesthetized Wistar rats was cannulated for administration of NO donor S-nitrosoglutathione. The left carotid artery was cannulated to detect APW. From rat APW, 35 hemodynamic parameters (HPs) and several their crossrelationships were evaluated. We introduced a new methodology to study “patterns” and connections of different signaling pathways, which are suggested from hysteresis and nonhysteresis crossrelationships of 35 rat HPs. Here, we show parallel time-dependent patterns of 35 HPs and some of their crossrelationships under the condition of transient increase of NO bioavailability by administration of S-nitrosoglutathione. Approximate nonhysteresis relationships were observed between systolic blood pressure and at least 11 HPs suggesting that these HPs, i.e., their signaling pathways, responding to NO concentration, are directly connected. Hysteresis relationships were observed between systolic blood pressure and at least 14 HPs suggesting that the signaling pathways of these HPs are indirectly connected. Totally, from the crossrelationships of 35 HPs, one can obtain 595 “patterns” and indication of direct or indirect connections between the signaling pathways. Conclusion. We described the procedure leading virtually to 595 relationships, from which “patterns” for transient NO increase and direct or indirect connections of signaling pathways can be suggested. From a clinical perspective, this approach may be used in animal models and in humans to create a data bank of patterns of crossrelationships of HPs for different cardiovascular conditions. By comparison with unknown patterns of studied APW with the data bank patterns, it would be possible to determine cardiovascular conditions of the studied subject from the recorded arterial blood pressure. Additionally, it can help to find molecular mechanism of particular (patho-) physiological conditions or drug action and may have predictive or diagnostic value.
Style APA, Harvard, Vancouver, ISO itp.
13

Manoj, Rahul, Raj Kiran V, P. M. Nabeel, Mohanasankar Sivaprakasam i Jayaraj Joseph. "Arterial pressure pulse wave separation analysis using a multi-gaussian decomposition model". Physiological Measurement, 10.05.2022. http://dx.doi.org/10.1088/1361-6579/ac6e56.

Pełny tekst źródła
Streszczenie:
Abstract Objective: Methods for separating the forward-backward components from blood pulse waves rely on simultaneously measured pressure and flow velocity from a target artery site. Modelling approaches for flow velocity simplify the wave separation analysis (WSA), providing a methodological and instrumentational advantage over the former; however, current methods are limited to the aortic site. In this work, a multi-Gaussian decomposition (MGD) modelled WSA (MGDWSA) is developed for a non-aortic site asuch as the carotid artery. While the model is an adaptation of the existing wave separation theory, it does not rely on the information of measured or modelled flow velocity. Approach: The proposed model decomposes the arterial pressure waveform using weighted and shifted multi-Gaussians, which are then uniquely combined to yield the forward (PF(t)) and backward (PB(t)) pressure wave. A study using the database of healthy (virtual) subjects was used to evaluate the performance of MGDWSA at the carotid artery and was compared against reference flow-based WSA methods. Main Results: The MGD modelled pressure waveform yielded a root-mean-square error (RMSE) < 0.35 mmHg. Reliable forward-backward components with a group average RMSE < 2.5 mmHg for PF(t) and PB(t) were obtained. When compared with the reference counterparts, the pulse pressures (ΔPF and ΔPB), as well as reflection quantification indices, showed a statistically significant strong correlation (r > 0.96, p < 0.0001) and (r > 0.83, p < 0.0001) respectively, with an insignificant (p > 0.05) bias. Significance: This study reports WSA for carotid pressure waveforms without assumptions on flow conditions. The proposed method has the potential to adapt and widen the vascular health assessment techniques incorporating pulse wave dynamics.
Style APA, Harvard, Vancouver, ISO itp.
14

Ayer, Julian G., Albert Avolio, Guy Marks, Jason A. Harmer i David S. Celermajer. "Abstract 2994: Gender-Related Differences in the Central Arterial Pressure Waveform Begin in Childhood and are Independent of Height". Circulation 118, suppl_18 (28.10.2008). http://dx.doi.org/10.1161/circ.118.suppl_18.s_802.

Pełny tekst źródła
Streszczenie:
Introduction Women develop age-related LV hypertrophy and symptomatic heart failure to a greater extent than men. Contributing to this may be a higher pulsatile afterload in women, with a higher central arterial systolic augmentation pressure (AP, peak pressure minus pressure at systolic shoulder) and augmentation index (AIx, ratio of AP to pulse pressure). It is unclear if these differences are due to gender per se or shorter female stature. We studied 8-year old children to determine if gender-related differences in carotid pressure augmentation are present in early life and if so, whether they are independent of height (Ht). Methods 406 children (age 8.0 ± 0.1, 49% girls) had anthropometry, brachial systolic and diastolic BP (SBP, DBP), heart rate (HR) and carotid and radial pressure waveforms (by applanation tonometry, calibrated to mean BP and DBP) assessed. Carotid ultrasound evaluated arterial elasticity [Carotid Artery Compliance (CAC), Stiffness Index (SI) and Young’s Elastic Modulus (YEM)]. Results Boys and girls had a similar Ht (129 ± 6 v 128 ± 6 cm), BMI (17.6 ± 3.1 v 17.5 ± 3.0), SBP (100 ± 7 v 101 ± 5 mmHg), DBP (59 ± 6 v 60 ± 5 mmHg) and HR (80 ± 10 v 82 ± 10 bpm). The carotid AP and AIx were significantly higher in girls (−4 ± 3 v −6 ± 4 mmHg and −12 ± 8 v −16 ± 9 respectively, p < 0.001), indicating greater systolic pressure augmentation. Time to onset of the reflected wave ( Tr ) and time to peak of the reflected wave were shorter in girls (154 ± 19 v 163 ± 18 msec, p < 0.001 and 206 ± 23 v 212 ± 22 msec, p = 0.03 respectively), indicating earlier wave reflection. Girls had a higher velocity index (Vr) estimated from Ht ( Vr = Ht /Tr , 8.4 ± 1.0 v 8.0 ± 0.9 m/sec, p = 0.001). Ejection duration, maximum rate of pressure rise and time to systolic peak (indicating effect of ventricular ejection on the carotid waveform) were not significantly different between genders. Boys, however, had stiffer carotid arteries than girls [lower CAC (5.8 ± 1.5 v 6.2 ± 1.8 %/10 mmHg, p = 0.016), higher SI (2.7 ± 0.7 v 2.5 ± 0.7, p = 0.012) and YEM (735 ± 217 v 681 ± 237, p = 0.021)]. Conclusion Even in the first decade of life, girls demonstrate greater central arterial pressure augmentation than boys, with earlier wave reflection. This is independent of height and may contribute to cardiovascular morbidity in females, later in life.
Style APA, Harvard, Vancouver, ISO itp.
15

Milkovich, Nicholas, Anastasia Gkousioudi, Francesca Seta, Béla Suki i Yanhang Zhang. "Harmonic Distortion of Blood Pressure Waveform as a Measure of Arterial Stiffness". Frontiers in Bioengineering and Biotechnology 10 (30.03.2022). http://dx.doi.org/10.3389/fbioe.2022.842754.

Pełny tekst źródła
Streszczenie:
Aging and disease alter the composition and elastic properties of the aortic wall resulting in shape changes in blood pressure waveform (BPW). Here, we propose a new index, harmonic distortion (HD), to characterize BPW and its relationship with other in vitro and in vivo measures. Using a Fourier transform of the BPW, HD is calculated as the ratio of energy above the fundamental frequency to that at the fundamental frequency. Male mice fed either a normal diet (ND) or a high fat, high sucrose (HFHS) diet for 2–10 months were used to study BPWs in diet-induced metabolic syndrome. BPWs were recorded for 20 s hourly for 24 h, using radiotelemetry. Pulse wave velocity (PWV), an in vivo measure of arterial stiffness, was measured in the abdominal aorta via ultrasound sonography. Common carotid arteries were excised from a subset of mice to determine the tangent modulus using biaxial tension-inflation test. Over a 24-h period, both HD and systolic blood pressure (SBP) show a large variability, however HD linearly decreases with increasing SBP. HD is also linearly related to tangent modulus and PWV with slopes significantly different between the two diet groups. Overall, our study suggests that HD is sensitive to changes in blood pressure and arterial stiffness and has a potential to be used as a noninvasive measure of arterial stiffness in aging and disease.
Style APA, Harvard, Vancouver, ISO itp.
16

Yavarimanesh, Mohammad, Hao-Min Cheng, Chen-Huan Chen, Shih-Hsien Sung, Aman Mahajan, Rabih A. Chaer, Sanjeev G. Shroff, Jin-Oh Hahn i Ramakrishna Mukkamala. "Abdominal aortic aneurysm monitoring via arterial waveform analysis: towards a convenient point-of-care device". npj Digital Medicine 5, nr 1 (4.11.2022). http://dx.doi.org/10.1038/s41746-022-00717-3.

Pełny tekst źródła
Streszczenie:
AbstractAbdominal aortic aneurysms (AAAs) are lethal but treatable yet substantially under-diagnosed and under-monitored. Hence, new AAA monitoring devices that are convenient in use and cost are needed. Our hypothesis is that analysis of arterial waveforms, which could be obtained with such a device, can provide information about AAA size. We aim to initially test this hypothesis via tonometric waveforms. We study noninvasive carotid and femoral blood pressure (BP) waveforms and reference image-based maximal aortic diameter measurements from 50 AAA patients as well as the two noninvasive BP waveforms from these patients after endovascular repair (EVAR) and from 50 comparable control patients. We develop linear regression models for predicting the maximal aortic diameter from waveform or non-waveform features. We evaluate the models in out-of-training data in terms of predicting the maximal aortic diameter value and changes induced by EVAR. The best model includes the carotid area ratio (diastolic area divided by systolic area) and normalized carotid-femoral pulse transit time ((age·diastolic BP)/(height/PTT)) as input features with positive model coefficients. This model is explainable based on the early, negative wave reflection in AAA and the Moens-Korteweg equation for relating PTT to vessel diameter. The predicted maximal aortic diameters yield receiver operating characteristic area under the curves of 0.83 ± 0.04 in classifying AAA versus control patients and 0.72 ± 0.04 in classifying AAA patients before versus after EVAR. These results are significantly better than a baseline model excluding waveform features as input. Our findings could potentially translate to convenient devices that serve as an adjunct to imaging.
Style APA, Harvard, Vancouver, ISO itp.
17

Bia, Daniel, Yanina Zócalo, Ramiro Sánchez, Gustavo Lev, Oscar Mendiz, Franco Pessana, Agustín Ramirez i Edmundo I. Cabrera-Fischer. "Aortic systolic and pulse pressure invasively and non-invasively obtained: Comparative analysis of recording techniques, arterial sites of measurement, waveform analysis algorithms and calibration methods". Frontiers in Physiology 14 (16.01.2023). http://dx.doi.org/10.3389/fphys.2023.1113972.

Pełny tekst źródła
Streszczenie:
Background: The non-invasive estimation of aortic systolic (aoSBP) and pulse pressure (aoPP) is achieved by a great variety of devices, which differ markedly in the: 1) principles of recording (applied technology), 2) arterial recording site, 3) model and mathematical analysis applied to signals, and/or 4) calibration scheme. The most reliable non-invasive procedure to obtain aoSBP and aoPP is not well established.Aim: To evaluate the agreement between aoSBP and aoPP values invasively and non-invasively obtained using different: 1) recording techniques (tonometry, oscilometry/plethysmography, ultrasound), 2) recording sites [radial, brachial (BA) and carotid artery (CCA)], 3) waveform analysis algorithms (e.g., direct analysis of the CCA pulse waveform vs. peripheral waveform analysis using general transfer functions, N-point moving average filters, etc.), 4) calibration schemes (systolic-diastolic calibration vs. methods using BA diastolic and mean blood pressure (bMBP); the latter calculated using different equations vs. measured directly by oscillometry, and 5) different equations to estimate bMBP (i.e., using a form factor of 33% (“033”), 41.2% (“0412”) or 33% corrected for heart rate (“033HR”).Methods: The invasive aortic (aoBP) and brachial pressure (bBP) (catheterization), and the non-invasive aoBP and bBP were simultaneously obtained in 34 subjects. Non-invasive aoBP levels were obtained using different techniques, analysis methods, recording sites, and calibration schemes.Results: 1) Overall, non-invasive approaches yielded lower aoSBP and aoPP levels than those recorded invasively. 2) aoSBP and aoPP determinations based on CCA recordings, followed by BA recordings, were those that yielded values closest to those recorded invasively. 3) The “033HR” and “0412” calibration schemes ensured the lowest mean error, and the “033” method determined aoBP levels furthest from those recorded invasively. 4) Most of the non-invasive approaches considered overestimated and underestimated aoSBP at low (i.e., 80 mmHg) and high (i.e., 180 mmHg) invasive aoSBP values, respectively. 5) The higher the invasively measured aoPP, the higher the level of underestimation provided by the non-invasive methods.Conclusion: The recording method and site, the mathematical method/model used to quantify aoSBP and aoPP, and to calibrate waveforms, are essential when estimating aoBP. Our study strongly emphasizes the need for methodological transparency and consensus for the non-invasive aoBP assessment.
Style APA, Harvard, Vancouver, ISO itp.
18

Singh, R. P., S. Tewari, A. Kapoor, P. K. Goel, N. Garg, S. Kumar i R. Khanna. "P41 Correlation of doppler ultrasound assessment of carotid femoral pulse wave velocity with coronary artery disease". European Heart Journal 41, Supplement_1 (1.01.2020). http://dx.doi.org/10.1093/ehjci/ehz872.035.

Pełny tekst źródła
Streszczenie:
Abstract Funding Acknowledgements self Background Arterial stiffness is an important cardiovascular risk factor. Carotid femoral pulse wave velocity (cfPWV) is simple noninvasive method to determine aortic stiffness. Arterial stiffness measures, cfPWV in particular, have been found to be correlate with stroke and peripheral artery disease. Usually SphygmoCor or Complior are used to calculate cfPWV. Doppler ultrasound can serve as an alternative to these methods. Purpose To assess cfPWV using doppler ultrasound and study its correlation with coronary artery disease and its severity. Methods cfPWV was assessed by ultrasound Doppler in patient aged 20-70 years undergoing coronary angiography. cfPWV was measured by sequential recordings of arterial pressure waveform at the carotid and femoral arteries with a Doppler ultrasound with ECG gating and calculated as the distance between the carotid and the femoral sampling site divided by the time interval. Result Of the 358 subjects studied, 243 had coronary artery disease(CAD) (&gt;50% diameter stenosis) and were further divided into single, double or triple vessel disease groups. 115 patients had mild CAD (&lt; 50% stenosis) or no CAD and served as controls. Baseline characteristics were similar except diabetes (more common in CAD group)(39.09% v/s 27.82%). cfPWV was found to increase with age in all groups. cfPWV was not significantly affected by sex, diabetes, dyslipidemia, BMI, smoking or hypothyroidism. Mean cfPWV was significantly higher in patients with CAD (8.99 v/s 6.51 m/s, p &lt; 0.001) and hypertensives (8.71 v/s 7.83 m/s, p &lt; 0.001). Patients with triple vessel disease(TVD) had significantly higher cfPWV (10.12 m/s) than those with double(DVD)(8.84 m/s) or single vessel disease(SVD)(8.28m/s)(p &lt; 0.001). Multinomial logistic regression revealed an odds ratio of 2.00, 2.375 and 3.368 respectively for SVD, DVD and TVD groups in comparison to controls (p &lt; 0.001). cfPWV value &gt; 7.25 m/s predicted CAD with sensitivity 78.6 % and specificity 74.8% (AUC =0.848, P &lt; 0.001). Conclusion Carotid femoral pulse wave velocity can be measured noninvasively by ultrasound Doppler. cfPWV increases with age and hypertension and has strong correlation with coronary artery disease and its severity. The cfPWV can be an independent risk factor and may be utilized for cardiovascular risk prediction. Abstract P41 Figure. cfPWV in various subgroups.
Style APA, Harvard, Vancouver, ISO itp.
19

Scheuermann, Britton, Shannon Parr, Stephen Hammond, Vanessa-Rose Turpin, Olivia Kunkel i Carl Ade. "Age-related impacts of wave transmission at the aorta-carotid bifurcation on local and global measures of arterial stiffness". Physiology 38, S1 (maj 2023). http://dx.doi.org/10.1152/physiol.2023.38.s1.5734426.

Pełny tekst źródła
Streszczenie:
Wave reflections in the periphery have been key in the understanding of aging-related changes in global arterial stiffness, as measured by carotid-femoral pulse-wave velocity (cfPWV). However, recent investigations have demonstrated benefits of using local measures of aortic arch PWV (aaPWV) in addition to considering cfPWV. The contribution of proximal wave reflections at the aorta-carotid bifurcation to aaPWV, as well as to the increasing discordance between aaPWV and cfPWV previously observed with aging, remain poorly understood. The purpose of the present investigation was to examine the impact of transmission of pressure and flow at the aorta-carotid bifurcation on aaPWV and cfPWV in healthy younger and older individuals. We hypothesized that aging-related stiffening of the carotid artery would enhance pressure transmission at the aorta-carotid bifurcation and redirect flow transmission towards a greater relative flow in the distal aortic arch, increasing cfPWV but having minimal impact on aaPWV. We recruited 15 participants, stratified into young adults (YA; n = 8, 4 women; age 20 ± 2.7 years) and older adults (OA; n = 7, 4 women; age 53 ± 2.2 years). Both aaPWV and cfPWV were assessed with ultrasound (Logiq S8, GE Healthcare) via the conventional foot-to-foot velocity waveform method. Carotid artery PWV (caPWV) was calculated using the Bramwell-Hill equation using M-mode scans and carotid pressure waveforms. Carotid, proximal, and distal aortic impedances were derived using estimated blood density, PWV values, and vessel cross-sectional areas. These impedance values allowed for calculation of the pressure and flow transmission coefficients describing the aorta-carotid bifurcation. Sex and BMI were not significantly different between groups (p > 0.05). YA had significantly lower cfPWV (5.2 ± 0.6 vs. 6.8 ± 0.8 m/s, p < 0.05) and caPWV (10.6 ± 0.9 vs. 16.9 ± 1.2 m/s, p < 0.05); however, aaPWV was similar between groups (p > 0.05). This resulted in a reduced pressure transmission coefficient in YA (0.91 ± 0.07 vs. 0.99 ± 0.05, p < 0.05) as well as a greater transmission of flow into the carotid artery relative to the distal aortic arch, represented as the carotid flow transmission coefficient over the distal aortic flow transmission coefficient (0.70 ± 0.20 vs. 0.41 ± 0.1, p <0.05). Linear regression indicated a significant association between caPWV and cfPWV in the entire group, even after adjustment for age, sex and BMI (β = 0.597, p = 0.01) whereas caPWV was not associated with aaPWV in univariate or multivariate analyses. Consistent with our hypothesis, present analyses suggest a role for pressure and flow transmission at the aorta-carotid bifurcation in the dissociation between local stiffness of the proximal aorta (aaPWV) and global arterial stiffness (cfPWV). This highlights the systemic nature of cfPWV, and suggests a need for specificity in the measure of arterial stiffness used and the target outcome of a given study. This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.
Style APA, Harvard, Vancouver, ISO itp.
20

Hao, Zhili, MD Mahfuzur Rahman, Jason Au, Chloe Athaide i Lauren Jutlah. "Axial Wall Displacement At the Common Carotid Artery is Associated with the Lamb Waves". Journal of Engineering and Science in Medical Diagnostics and Therapy, 16.11.2022, 1–40. http://dx.doi.org/10.1115/1.4056267.

Pełny tekst źródła
Streszczenie:
Abstract As compared with its radial wall displacement, axial wall displacement at the common carotid artery (CCA) carries independent clinical values, but its physical mechanisms are unclear. This study aims to investigate whether axial wall displacement at the CCA is solely from Young waves. A pulse wave propagation theory is utilized to identify two types of waves, Young waves and Lamb waves, in an artery, and identifies two sources for axial wall displacement, wall shear stress and radial wall displacement gradient with a factor of the difference between axial and circumferential initial tension, which reveals the influence of axial initial tension on the waveform of axial wall displacement. Theoretical expressions are derived for calculating the waveforms of axial wall displacement and its two sources in the Young waves. With the measured pulsatile pressure and blood velocity at the CA of three healthy adults as the inputs, the waveforms of axial wall displacement in the Young waves are calculated at different values of axial initial tension, and are found to greatly differ from their measured counterparts. As such, the Lamb waves may contribute to axial wall displacement at the CCA and the associated physical and physiological implications are discussed. Given the clinical values of axial wall displacement at the CCA, the Lamb waves may play a non-negligible role in determining arterial health and needs to be further studied for a comprehensive assessment of arterial wall mechanics.
Style APA, Harvard, Vancouver, ISO itp.
21

Heffernan, Kevin, Lee Stoner, Michelle L. Meyer, Adam Keifer, Lauren Bates, Patricia Pagan Lassalle, Erik D. Hanson i in. "Associations between estimated and measured carotid-femoral pulse wave velocity in older Black and White adults: the atherosclerosis risk in communities (ARIC) study". Journal of Cardiovascular Aging, 2022. http://dx.doi.org/10.20517/jca.2021.22.

Pełny tekst źródła
Streszczenie:
Introduction: Aortic stiffness offers important insight into vascular aging and cardiovascular disease (CVD) risk. The referent measure of aortic stiffness is carotid-femoral pulse wave velocity (cfPWV). cfPWV can be estimated (ePWV) from age and mean arterial pressure. Few studies have directly compared the association of ePWV to measured cfPWV, particularly in non-White adults. Moreover, whether ePWV and cfPWV correlate similarly with CVD risk remains unexplored. Aim: (1) To estimate the strength of the agreement between ePWV and cfPWV in both Black and White older adults; and (2) to compare the associations of ePWV and cfPWV with CVD risk factors and determine whether these associations were consistent across races. Methods and Results: We evaluated 4478 [75.2 (SD 5.0) years] Black and White older adults in the Atherosclerosis Risk in Communities (ARIC) Study. cfPWV was measured using an automated pulse waveform analyzer. ePWV was derived from an equation based on age and mean arterial pressure. Association and agreement between the two measurements were determined using Pearson’s correlation coefficient (r), standard error of estimate (SEE), and Bland-Altman analysis. Associations between traditional risk factors with ePWV and cfPWV were evaluated using linear mixed regression models. We observed weak correlations between ePWV and cfPWV within White adults (r = 0.36) and Black adults (r = 0.31). The mean bias for Bland-Altman analysis was low at -0.17 m/s (95%CI: -0.25 to -0.09). However, the inspection of the Bland-Altman plots indicated systematic bias (P < 0.001), which was consistent across race strata. The SEE, or typical absolute error, was 2.8 m/s suggesting high variability across measures. In models adjusted for sex, prevalent diabetes, the number of prevalent cardiovascular diseases, and medication count, both cfPWV and ePWV were positively associated with heart rate, triglycerides, and fasting glucose, and negatively associated with body mass index (BMI) and smoking status in White adults (P < 0.05). cfPWV and ePWV were not associated with heart rate, triglycerides, and fasting glucose in Black adults, while both measures were negatively associated with BMI in Black adults. Conclusions: Findings suggest a weak association between ePWV and cfPWV in older White and Black adults from ARIC. There were similar weak associations between CVD risk factors with ePWV and cfPWV in White adults with subtle differences in associations in Black adults. One sentence summary: Estimated pulse wave velocity is weakly associated with measured carotid-femoral pulse wave velocity in older Black and White adults in ARIC.
Style APA, Harvard, Vancouver, ISO itp.
22

Bruno, R. M., N. Di Lascio, A. Al Hussaini, S. Vitali, P. Rossi, D. Caramella, D. Regazzoli i in. "P2538Arterial stiffness and remodeling from large to small arteries in patients with spontaneous coronary artery dissection: evidence for a systemic subclinical involvement". European Heart Journal 40, Supplement_1 (1.10.2019). http://dx.doi.org/10.1093/eurheartj/ehz748.0866.

Pełny tekst źródła
Streszczenie:
Abstract Background and aim Spontaneous coronary artery dissection (SCAD) is a major cause of acute coronary syndrome in women aged 50 years or less (22–43%). Its etiology is still unknown, though an association with systemic diseases such as fibromuscular dysplasia and collagenopathies has been found. This study is aimed at investigating the presence of subclinical structural and functional alterations in extracoronary districts in SCAD patients. Methods The design was a case-control study. Carotid, radial and digital arteries were scanned by standard or ultrahigh frequency ultrasound; clips were analyzed by automated image analysis software for diameter, intima-media thickness (IMT) and local distensibility. Applanation tonometry was used to obtain carotid-femoral pulse wave velocity, a measure of regional, aortic stiffness, and carotid pressure waveform. Results 30 patients previously diagnosed with SCAD (27 women, age 51±10 years, 8 treated hypertensives, 4 smokers, mean BP 83±11mmHg, BMI 25±5kg/mq) and 30 controls, matched for age, sex and CV risk factors by propensity score, were enrolled. 18 SCAD patients underwent PTCA and 6 had a diagnosis of extracoronary fibromuscular dysplasia. In the left radial artery, wall thickness, cross-sectional area (2.96±1.07 vs 1.79±1.41mm2, p=0.008), and wall inhomogeneity were increased, especially in the outer layer, whereas diameter, wall/lumen ratio and distensibility were comparable to controls. In the left common carotid artery, an increased carotid stiffness was shown in SCAD (5.99±0.89 m/s vs 5.6±0.85, 0.03), while IMT tended to be increased bilaterally (0.63±0.12 vs 0.59±0.10mm, p=0.08). Aortic stiffness was similar in the two groups (7.0±1.9 vs 6.7±1.7m/s, p=0.60). Carotid (20.4±14.2 vs 11.9±15.0%, p=0.03), but not aortic augmentation index, was increased bilaterally. Conclusions SCAD patients showed a peculiar pattern of alterations in vascular remodeling and stiffness in extracoronary arterial segments such as the carotid and radial arteries, supporting the hypothesis that a systemic susceptibility is present even in the absence of systemic diseases.
Style APA, Harvard, Vancouver, ISO itp.
23

Heusinkveld, Maarten H. G., Robert J. Holtackers, Bouke P. Adriaans, Jos Op't Roodt, Theo Arts, Tammo Delhaas, Koen D. Reesink i Wouter Huberts. "Complementing sparse vascular imaging data by physiological adaptation rules". Journal of Applied Physiology, 29.10.2020. http://dx.doi.org/10.1152/japplphysiol.00250.2019.

Pełny tekst źródła
Streszczenie:
Introduction:Mathematical modeling of pressure and flow waveforms in blood vessels using pulse wave propagation (PWP)-models has tremendous potential to support clinical decision-making. For a personalized model outcome, measurements of all modeled vessel radii and wall thicknesses are required. In clinical practice, however, data sets are often incomplete. To overcome this problem, we hypothesized that the adaptive capacity of vessels in response to mechanical load could be utilized to fill in the gaps of incomplete patient-specific data sets. Methods:We implemented homeostatic feedback loops in a validated PWP model to allow adaptation of vessel geometry to maintain physiological values of wall stress and wall shear stress. To evaluate our approach, we gathered vascular MRI and ultrasound data sets of wall thicknesses and radii of central and arm arterial segments of ten healthy subjects. Reference models (i.e. termed RefModel, n=10) were simulated using complete data, whereas adapted models (AdaptModel, n=10) used data of one carotid artery segment only while the remaining geometries in this model were estimated using adaptation. We evaluated agreement between RefModel and AdaptModel geometries, as well as between pressure and flow waveforms of both models. Results:Limits of agreement (bias±2SD of difference) between AdaptModel and RefModel radii and wall thicknesses were 0.2±2.6 mm and -140±557 μm, respectively. Pressure and flow waveform characteristics of the AdaptModel better resembled those of the RefModels as compared to the model in which the vessels were not adapted.Conclusions:Our adaptation-based PWP-model enables personalization of vascular geometries even when not all required data is available.
Style APA, Harvard, Vancouver, ISO itp.
24

Calvez, Valentin, Marco Palladino, Giulio Montefusco, Vincenzo Cesario, Claudia Fofi, Giuseppino M. Ciavarella, Massimo Volpe i Carmine Savoia. "Abstract P517: Dialysis Vintage Longer Than Sixty Months Contributes to Increased Arterial Stiffness and Impaired Diastolic Function in Patients with End-stage Renal Disease". Hypertension 70, suppl_1 (wrzesień 2017). http://dx.doi.org/10.1161/hyp.70.suppl_1.p517.

Pełny tekst źródła
Streszczenie:
Hemodialysis (HD) may induce vascular stiffness through several mechanisms. We sought to determine the role of dialysis vintage (DV) on the development of cardiovascular alterations. We studied 14 patients in chronic HD and 24 newly diagnosed never treated hypertensive patients and 16 normotensive controls. The patients in HD were divided in two groups according to DV: <60-months (DV<60,n=7) or >60-months (DV>60,n=7). After HD session, when dry weight was reached, we evaluated peripheral blood pressure (pBP), the parameters derived by tonometric analysis of the pulse waveform (central blood pressure-cBP-, Subendocardial Viability Ratio-SEVR-, carotid-femoral pulse wave velocity-cf-PWV-) and those derived from echocardiography: ejection fraction (EF-for systolic function) and E/e’ (for diastolic function), and the ultrafiltration volume (UV). Calcium/phosphate (Ca/P) levels, serum albumin, and Kt/V were evaluated retrospectively on repeated measurements over the past 5 years. All the groups were similar for sex and BMI, both DV<60 and DV>60 were older than hypertensives and controls (58.33±3.71 and 59.83±7.98 vs 44.14±1.28 and vs 40.63±2.05 years, respectively, P<0.05). Both DV<60 and DV>60 presented similar levels of Ca/P, serum albumin, Kt/V and UV. pBP was increased and similar to hypertensives in DV>60 vs DV<60 (systolic-pBP: 154.2±4.5 vs 132.5±5.18 mmHg, P<0.01 and diastolic-pBP: 90.4±49 vs 78.5±3.3 mmHg, P<0.01). Likewise cBP was increased and similar to hypertensive patients in DV>60 vs DV<60 (systolic-cBP: 140.8±8.4 vs 111.2±3.36 mmHg, P<0.001 and diastolic-cBP: 88.2±3.73 vs 72.33±7.78 mmHg, respectively, P<0.05). cf-PWV was similar in normotensives, hypertensives and DV<60, and increased only in DV>60 vs DV<60 (9.6±1.4 vs 7.13±1.4 m/s, p<0.05). SEVR and EF were preserved and similar in all the groups. E/e’ was significantly increased only in the groups in HD, however it was higher in DV>60 vs DV<60 (9.16±1.14 vs 6.96±0.72, P<0.01). In conclusion, only patients with DV>60 presented increased aortic stiffness. This was associated to higher BP and diastolic dysfunction. Hence, chronic HD, particularly after 60 months, may play a putative role in developing cardiovascular alterations in patients with end-stage renal disease.
Style APA, Harvard, Vancouver, ISO itp.
Oferujemy zniżki na wszystkie plany premium dla autorów, których prace zostały uwzględnione w tematycznych zestawieniach literatury. Skontaktuj się z nami, aby uzyskać unikalny kod promocyjny!

Do bibliografii