DOCSLIB.ORG

Clinical Application of Pulsatility Index

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Clinical Application of Pulsatility Index REVIEW ARTICLE Melanie Wielicka* , Jolanta Neubauer-Geryk* , Grzegorz Kozera , Leszek Bieniaszewski *Both authors had an equal authorship in the study Clinical Physiology Unit, Medical Simulation Centre, Medical University of Gdansk, Gdansk, Poland Clinical application of pulsatility index Corresponding author: ABSTRACT Jolanta Neubauer-Geryk, Clinical Pulsatility index (PI) is defined as the difference between the peak systolic flow and minimum diastolic flow Physiology Unit, Medical Simulation Centre, Medical University of Gdansk, velocity, divided by the mean velocity recorded throughout the cardiac cycle. It is a non-invasive method Gdansk, Poland, Dębowa 25 Str., of assessing vascular resistance with the use of Doppler ultrasonography. It was first introduced in 1974 80-204 Gdansk, Poland, by Gosling and King and is also known as the Gosling Index. PI as a method of examining macrocircula- e-mail: [email protected] tion has a variety of clinical applications. For instance, in diabetic patients, it has been measured on the common carotid, middle cerebral or renal arteries to help predict complications such as cerebrovascular disease or nephropathy. In hypertensive patients, it has been used to assess complications and assess the chronicity of the disease. To our knowledge, despite the diverse use of this ultrasonographic parameter, there is a deficiency in reports that would comprehensively summarize its clinical applications. Based on our extensive review of the literature and the gathered information, we conclude that pulsatility index (PI) is an easy to obtain parameter with a broad range of both, research and clinical applications. Medical Research Journal 2020; It has been widely used in the assessment of macrocirculation in highly prevalent chronic medical condi- Volume 5, Number 3, 201–210 tions, such as hypertension, both type 1 and type 2 diabetes and thyroid disorders. 10.5603/MRJ.a2020.0016 Copyright © 2020 Via Medica Key words: pulsatility index, clinical application, cerebral artery, carotid artery, renal artery ISSN 2451–2591 Med Res J 2020; 5 (3): 201–210 Introduction tions, including increased stress on the left ventricle, a gradual increase in blood pressure and, eventually, Macrovascular complications, such as cardiovascu- even end-organ damage through the transmission of lar and cerebrovascular events, are the leading cause harmful pulsation into the microcirculation. Thus, the of mortality in patients with common vascular risk fac- increase in pulsatility associated with loss of elastic tors, such as diabetes or hypertension. It is estimated recoil in large blood vessels has detrimental effects on that, globally, approximately 32.2% of type 2, 30.3% of global cardiovascular health. type 1 diabetic and 30% hypertensive patients suffer Pulsatility index (PI) is defined as the difference from cardiovascular complications [1–5]. between the peak systolic flow and minimum diastolic Pulsatility is an intrinsic property and an integral flow velocity, divided by the mean velocity recorded aspect of the cardiovascular system, strongly related to throughout the cardiac cycle. It is a non-invasive elasticity of arteries. The natural pulsations in pressure method of assessing vascular resistance with the use caused by each contraction of the left ventricle are large- of doppler ultrasonography. It was first introduced in ly diminished thanks to elasticity of large arteries. As the 1974 by Gosling and King, thus is also known as the aorta expands, it stores a portion of the stroke volume, Gosling Index [7, 8]. Due to the vast applications of this so that the microvasculature is less exposed to pulsatile parameter, we comprehensively discuss PI use and its stress [6]. Thus, the elasticity of blood vessels allows clinical significance in the assessment of microcircula- for blunting down harmful pulsations in the large arter- tory system (Fig. 1). ies before they reach end-organ microcirculation [6]. However, from early on in childhood, arterial walls con- tinually increase in stiffness through the loss of elastic Macrocirculation and pulsatility fibers. This process is further augmented by disorders of metabolism such as hyperlipidemia or diabetes The great physiological and clinical significance mellitus through a variety of mechanisms. A decrease of arterial pulsatility is related to how the large, elastic in elasticity is associated with a multitude of complica- arteries serve as a type of reservoir that functions to www.journals.viamedica.pl/medical_research_journal 201 MEDICAL RESEARCH JOURNAL 2020. vol. 5. no. 3 The impact of aging on arterial stiffness and Velocity pulsatility has been demonstrated in several stud- V max– V min ies. Zarrinkoob et al [12] investigated how age and PI = V mean sex impacts the dampening of the pulsatile flow V max from the proximal to the distal cerebral arteries. The study groups consisted of 45 healthy elderly, with a mean are of 71 years, and 49 young healthy subjects, with a mean age of 25 years. The authors V mean found that especially cerebral pulsatile flow was dampened from proximal to distal parts of the ce- rebral arterial system and that this dampening was V min more pronounced in the younger studied group. Time This demonstrates how aging impacts the ability of larger, more elastic arteries to diminish delivery of harmful pulsations to smaller blood vessels. Several Figure 1. Calculation of the Pulsatility (Gosling) Index (PI). other authors have also shown an increase in PI of V max — maximal flow velocity, V min — minimal flow the cerebrovascular circulation with an increase in velocity, V mean — mean flow velocity age [13, 14]. Additionally, Schoning et al [15, 16] used ultrasound examination to establish PI at the common carotid artery in healthy children, adoles- store blood during systole and expel it to the peripheral cents and adults. They were able to demonstrate how circulation during diastole within each contraction of arterial hemodynamics change with age and show the left ventricle [4, 5]. This provides a constant flow that PI is an age-dependent parameter. of blood into the microvascular beds throughout the It is also worth mentioning how an increase in arterial cardiac cycle, allowing for continuous exchange of diameter affects PI. It has been described that in arterial substances between tissues and plasma. Loss of this aneurysms, a Windkessel effect takes place, where the elastic reservoir has several negative effects on the aneurysm acts as a reservoir for blood during systole cardiovascular system and has the potential to damage and releases it during diastole. This results in lower end-organ circulation. With the loss of elasticity, there pulse pressure, because of increased vascular resis- is an increase in pulsatile load of the heart, which has tance distally [9, 10]. This was supported by a study detrimental effects on the left ventricle through increas- by Hussein et al [9], where the authors demonstrated ing its mass and thus the myocardial oxygen demand the relationship between the size of internal carotid [9]. Additionally, the increased pulsations resulting artery aneurysms and distal intracranial hemodynam- from the stiffness of large vessels are believed to af- ics. They have measured flow and pulsatility index within fect the capillary networks, resulting in microvascular bilateral middle cerebral arteries and internal carotid complications, as they allow the harmful pulsations to arteries prior to initiating any treatment. They found be conducted into end-organ microcirculation [10]. that larger aneurysmal size (>10mm) had a significant This is particularly important when it comes to organs correlation with higher ipsilateral middle cerebral artery characterized by high flow and low resistance, such as PI. Conversely, a decrease in aortic diameter causes the brain and the kidneys [6]. an increase in vascular resistance. An increase in The complex elastic fiber mesh in large blood pulsatility index is a reliable marker of distal resistance vessels begins its synthesis development in early em- in the examined blood vessel [11]. Pulsatility index as bryogenesis, a process which continues up until early a measure of vascular resistance has also been used childhood. As a result, adults have a relatively fixed in examining patients with carotid artery stenosis as amount of elastic fibers in their aorta, which slowly well as aortic stenosis, helping in assessment of the stretch out, degenerate and become replaced by much efficacy of treatment. less compliant collagen fibers [9]. As shown by Eberth PI as a method of examining macrocirculation has et al increasing pulsatile pressure and continuous a wide range of clinical applications. For instance, in flow injury on the vascular wall result in a significant diabetic patients it has been measured on the common increase in the number of cells and an increased col- carotid, middle cerebral or renal arteries to help predict lagen-to-elastin ratio with further aortic wall thickening complications such as cerebrovascular disease or and luminal narrowing [11]. The progression of arterial nephropathy [12, 13]. In hypertensive patients, it has stiffening and the increase in flow pulsatility in the el- been used to assess complications and assess the derly occurs due to the fact that the less elastic vessels chronicity of disease [14]. To our knowledge, despite are no longer capable of buffering the flow pulsations the diverse use of this ultrasonographic parameter, generated with each ventricular
Load more

Recommended publications
  • Disruption of Vascular Ca2+-Activated Chloride Currents Lowers Blood Pressure Christoph Heinze,1 Anika Seniuk,2 Maxim V
    Research article Disruption of vascular Ca2+-activated chloride currents lowers blood pressure Christoph Heinze,1 Anika Seniuk,2 Maxim V. Sokolov,3 Antje K. Huebner,1 Agnieszka E. Klementowicz,3 István A. Szijártó,4,5 Johanna Schleifenbaum,4 Helga Vitzthum,2 Maik Gollasch,4 Heimo Ehmke,2 Björn C. Schroeder,3 and Christian A. Hübner1 1Institut für Humangenetik, Universitätsklinikum Jena, Friedrich-Schiller Universität Jena, Jena, Germany. 2Institut für Zelluläre und Integrative Physiologie, Universitätsklinikum Hamburg Eppendorf, Hamburg, Germany. 3Max-Delbrück Centrum für Molekulare Medizin (MDC) and NeuroCure, Berlin, Germany. 4Medizinische Klinik mit Schwerpunkt Nephrologie und Internistische Intensivmedizin, Charité – Universitätsmedizin Berlin, Experimental and Clinical Research Center (ECRC), Berlin, Germany. 5Interdisziplinäres Stoffwechsel-Centrum, Charité – Universitätsmedizin Berlin, Berlin, Germany. High blood pressure is the leading risk factor for death worldwide. One of the hallmarks is a rise of periph- eral vascular resistance, which largely depends on arteriole tone. Ca2+-activated chloride currents (CaCCs) in vascular smooth muscle cells (VSMCs) are candidates for increasing vascular contractility. We analyzed the vascular tree and identified substantial CaCCs in VSMCs of the aorta and carotid arteries. CaCCs were small or absent in VSMCs of medium-sized vessels such as mesenteric arteries and larger retinal arterioles. In small vessels of the retina, brain, and skeletal muscle, where contractile intermediate cells or pericytes gradually replace VSMCs, CaCCs were particularly large. Targeted disruption of the calcium-activated chloride channel TMEM16A, also known as ANO1, in VSMCs, intermediate cells, and pericytes eliminated CaCCs in all ves- sels studied. Mice lacking vascular TMEM16A had lower systemic blood pressure and a decreased hyperten- sive response following vasoconstrictor treatment.
    [Show full text]
  • Chapter 15 Hydrocephalus: New Theories and New Shunts?
    Chapter 15 Hydrocephalus: New Theories and New Shunts? Marvin Bergsneider, M.D. Introduction The optimal and ideal management for any given clinical disorder should be fundamentally aimed at reversing or preventing the pathobiological mechanism underlying the disorder. For hydrocephalus, our current incomplete understanding of the pathophysiology is, in part, responsible for significant inadequacies of the current mainstay of treatment: the cerebrospinal fluid (CSF) shunt. The management of shunt-related problems and disorders has become a de facto subspecialty within neurosurgery. Although it is clear that the treatment of hydrocephalus was vastly improved with the introduction of the differential pressure valve by Nulsen and Spitz (25) half a century ago, it can be argued that little further improvement has occurred in the interim. A randomized, multicenter trial failed to show a benefit from “technologically advanced” valve designs compared with a standard differential pressure valve (7) similar to the one designed by John Holter. Probably one of the most refractory problems of CSF shunt diversion has been that of over-drainage. In children, excessive CSF drainage by the shunt is an important cause of shunt failure caused by ventricular catheter obstruction resulting from ventricular collapse. Over time, shunted hydrocephalic children can develop the slit-ventricle syndrome—one of the most challenging conditions to treat in neurosurgery. In older adults, shunt over-drainage can result in the devastating complication of subdural hematoma. A similar degree of ventricular reduction occurs despite the implementation of valve designs touted to prevent it, including flow-limiting valves and antisiphon devices (31). Why have efforts failed to prevent excessive CSF drainage by shunts? Although the answer is likely multifactorial, we argue that the fundamental problem lies in our incomplete and overly simplistic understanding of the hydrodynamics of hydrocephalus and in vivo shunt physiology.
    [Show full text]
  • Ingeniería Cardiovascular - Del Laboratorio a La Clínica
    INGENIERÍA CARDIOVASCULAR - DEL LABORATORIO A LA CLÍNICA INGENIERÍA CARDIOVASCULAR DEL LABORATORIO A LA CLÍNICA RICARDO L. ARMENTANO Departamento de Ingeniería Biológica, CENUR LITOTAL NORTE, URUGUAY Facultad de Ingeniería, UNIVERSIDAD DE LA REPÚBLICA, URUGUAY. Introducción La Ingeniería Cardiovascular integra elementos de la biología, la ingeniería eléctrica, la ingeniería mecánica, la matemática y la física con el fin de describir y comprender al sistema cardiovascular. Su objetivo es desarrollar, comprobar y validar una interpretación predictiva y cuantitativa del sistema cardiovascular en un adecuado nivel de detalle, y aplicar conceptos resultantes hacia la solución de diversas patologías. La dinámica del sistema cardiovascular caracteriza al corazón y al sistema vascular como un todo, y comprende la física del sistema circulatorio incluyendo el continente (las paredes arteriales) y el contenido (sangre), así como la interrelación entre ambos. La pared arterial y la sangre contienen la información esencial sobre el estado fisiológico del sistema circulatorio completo, en tanto que la interdependencia de estos componentes está relacionada con procesos complejos que podrían explicar la formación de lesiones en la pared vascular, tales como las placas de ateroma, o el aumento en la rigidez de la pared como está descripto en la hipertensión arterial. Los incipientes cambios morfológicos de la pared arterial inducidos por procesos patológicos pueden ser considerados marcadores precoces de futuras alteraciones circulatorias. La modelización matemática de la pared arterial, a partir de la estimación de los coeficientes de la ecuación del modelo, obtenida a través de estudios en animales conscientes, constituye una herramienta de gran valor e indispensable para una mejor comprensión de la génesis de las enfermedades cardiovasculares.
    [Show full text]
  • Simple Models of the Cardiovascular System for Educational and Research Purposes
    56 ORIGINAL ARTICLE SIMPLE MODELS OF THE CARDIOVASCULAR SYSTEM FOR EDUCATIONAL AND RESEARCH PURPOSES Tomáš Kulhánek*, Martin Tribula, Jiří Kofránek, Marek Mateják Institute of Pathological Physiology, 1st Faculty of Medicine, Charles University in Prague, Prague, Czech Republic * Corresponding author: [email protected] Article history AbstrAct — Modeling the cardiovascular system as an analogy of an electri- Received 14 September 2014 cal circuit composed of resistors, capacitors and inductors is introduced in many Revised 30 October 2014 research papers. This contribution uses an object oriented and acausal approach, Accepted 4 November 2014 which was recently introduced by several other authors, for educational and re- Available online 24 November 2014 search purpose. Examples of several hydraulic systems and whole system model- ing hemodynamics of a pulsatile cardiovascular system are presented in Modelica Keywords language using Physiolibrary. Modelica modeling physiology cardiovascular system Physiolibrary INTRODUCTION grown technology from the scientific community, such as SBML [10], JSIM [11] or CellML [1,12] or industrial The mathematical formalization of the cardiovas- standard technology implemented by several vendors, cular system (CVS), i.e. the models, can be divided such as the Modelica language [8,9]. into two main approaches. The first approach builds This article introduces a modeling method which 3D models with geometrical, mechanical properties follows the second approach for modeling CVS as and the time-dependence
    [Show full text]
  • Radial and Longitudinal Motion of the Arterial Wall: Their Relation to Pulsatile Pressure and Flow in the Artery Dan Wang Old Dominion University
    Old Dominion University ODU Digital Commons Mechanical & Aerospace Engineering Faculty Mechanical & Aerospace Engineering Publications 2018 Radial and Longitudinal Motion of the Arterial Wall: Their Relation to Pulsatile Pressure and Flow in the Artery Dan Wang Old Dominion University Linda Vahala Old Dominion University Zhili Hao Old Dominion University Follow this and additional works at: https://digitalcommons.odu.edu/mae_fac_pubs Part of the Biomechanical Engineering Commons, Cardiovascular System Commons, and the Electrical and Computer Engineering Commons Repository Citation Wang, Dan; Vahala, Linda; and Hao, Zhili, "Radial and Longitudinal Motion of the Arterial Wall: Their Relation to Pulsatile Pressure and Flow in the Artery" (2018). Mechanical & Aerospace Engineering Faculty Publications. 69. https://digitalcommons.odu.edu/mae_fac_pubs/69 Original Publication Citation Wang, D., Vahala, L., & Hao, Z. (2018). Radial and longitudinal motion of the arterial wall: Their er lation to pulsatile pressure and flow in the artery. Physical Review E, 98(3), 032402. doi:10.1103/PhysRevE.98.032402 This Article is brought to you for free and open access by the Mechanical & Aerospace Engineering at ODU Digital Commons. It has been accepted for inclusion in Mechanical & Aerospace Engineering Faculty Publications by an authorized administrator of ODU Digital Commons. For more information, please contact [email protected]. PHYSICAL REVIEW E 98, 032402 (2018) Radial and longitudinal motion of the arterial wall: Their relation to pulsatile pressure
    [Show full text]
  • Arterial Pressure Waveforms
    Section 3 Cardiovascular physiology Chapter 33 Arterial pressure waveforms The rate and character of the arterial pulse has been What is the arterial pressure wave? used for millennia for the diagnosis of a wide range of disorders. Perhaps more useful, however, is the direct Ejection of blood into the aorta generates both an cannulation of an artery, which allows quantitative arterial pressure wave and a blood flow wave. The information to be extracted. arterial pressure wave is caused by the distension of the elastic walls of the aorta during systole. The wave propagates down the arterial tree at a much faster rate What is the Windkessel effect? (around 4 m/s) than the mean aortic blood velocity During systole, the LV ejects around 70 mL of blood (20 cm/s). It is the arterial pressure wave that is felt as into the aorta (the SV). The elastic aortic walls expand the ‘radial pulse’, not the blood flow wave. to accommodate the SV, moderating the consequent increase in intra-aortic pressure from a DBP of Describethearterialpressurewaveform 80 mmHg to an SBP of 120 mmHg. The ejected blood possesses kinetic energy, whilst there is storage of for the aorta potential energy in the stretched aortic wall. In dia- Starting from end-diastole (Figure 33.1), the pressure stole, recoil of the aortic wall converts the stored generated by the LV ejects the SV into the aorta. The potential energy back into kinetic energy. This main- intra-aortic pressure rises to a peak value, the SBP, tains the onward flow of blood during diastole, and then falls to a trough, the DBP.
    [Show full text]
  • Elastic Fibers and Biomechanics of the Aorta: Insights from Mouse Studies
    Review MATBIO-1552; No. of pages: 13; 4C: Elastic fibers and biomechanics of the aorta: Insights from mouse studies Hiromi Yanagisawa a and Jessica Wagenseil b a - Life Science Center for Survival Dynamics, Tsukuba Advanced Research Alliance (TARA), University of Tsukuba, Tsukuba 305-8577, Japan b - Department of Mechanical Engineering and Materials Science, Washington University at St. Louis, St. Louis, MO, USA Correspondence to Hiromi Yanagisawa and Jessica Wagenseil: [email protected], [email protected]. https://doi.org/10.1016/j.matbio.2019.03.001 Abstract Elastic fibers are major components of the extracellular matrix (ECM) in the aorta and support a life-long cycling of stretch and recoil. Elastic fibers are formed from mid-gestation throughout early postnatal development and the synthesis is regulated at multiple steps, including coacervation, deposition, cross- linking, and assembly of insoluble elastin onto microfibril scaffolds. To date, more than 30 molecules have been shown to associate with elastic fibers and some of them play a critical role in the formation and maintenance of elastic fibers in vivo. Because the aorta is subjected to high pressure from the left ventricle, elasticity of the aorta provides the Windkessel effect and maintains stable blood flow to distal organs throughout the cardiac cycle. Disruption of elastic fibers due to congenital defects, inflammation, or aging dramatically reduces aortic elasticity and affects overall vessel mechanics. Another important component in the aorta is the vascular smooth muscle cells (SMCs). Elastic fibers and SMCs alternate to create a highly organized medial layer within the aortic wall. The physical connections between elastic fibers and SMCs form the elastin-contractile units and maintain cytoskeletal organization and proper responses of SMCs to mechanical strain.
    [Show full text]
  • Behavioural Representation of the Aorta by Utilizing Windkessel and Agent-Based Modelling
    INFORMATICA, 2021, Vol. 32, No. 3, 499–516 499 © 2021 Vilnius University DOI: https://doi.org/10.15388/21-INFOR456 Behavioural Representation of the Aorta by Utilizing Windkessel and Agent-Based Modelling Sevcan EMEK1,∗, Şebnem BORA2, Vedat EVREN3, İbrahim ÇAKIRLAR4 1 Faculty of Engineering, Department of Computer Engineering, Manisa Celal Bayar University, 45140 Manisa, Turkey 2 Faculty of Engineering, Department of Computer Engineering, Ege University, 35100 İzmir, Turkey 3 Faculty of Medicine, Department of Physiology, Ege University, 35100 İzmir, Turkey 4 SAP Concur, France e-mail: [email protected], [email protected], [email protected], [email protected] Received: November 2020; accepted: July 2021 Abstract. The main objective of the present paper is to report two studies on mathematical and computational techniques used to model the behaviour of the aorta in the human cardiovascular system. In this paper, an account of the design and implementation of two distinct models is pre- sented: a Windkessel model and an agent-based model. Windkessel model represents the left heart and arterial system of the cardiovascular system in the physiological domain. The agent-based model offers a simplified account of arterial behaviour by randomly generating arterial parameter values. This study has described the mechanism how and when the left heart contracts and pumps the blood out of the aorta, and it has taken the Windkessel model one step further. The results of this study show that the dynamics of the aorta can be explored in each modelling approaches as proposed and implemented by our research group. It is thought that this study will contribute to the literature in terms of development of the Windkessel model by considering its timing and redesigning it with digital electronics perspective.
    [Show full text]
  • Regulation of Blood Flow in the Retinal Trilaminar Vascular Network
    11504 • The Journal of Neuroscience, August 20, 2014 • 34(34):11504–11513 Systems/Circuits Regulation of Blood Flow in the Retinal Trilaminar Vascular Network Tess E. Kornfield and Eric A. Newman Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455 Light stimulation evokes neuronal activity in the retina, resulting in the dilation of retinal blood vessels and increased blood flow. This response, named functional hyperemia, brings oxygen and nutrients to active neurons. However, it remains unclear which vessels mediatefunctionalhyperemia.Wehavecharacterizedbloodflowregulationintheratretinainvivobymeasuringchangesinretinalvessel diameter and red blood cell (RBC) flux evoked by a flickering light stimulus. We found that, in first- and second-order arterioles, flicker evoked large (7.5 and 5.0%), rapid (0.73 and 0.70 s), and consistent dilations. Flicker-evoked dilations in capillaries were smaller (2.0%) and tended to have a slower onset (0.97 s), whereas dilations in venules were smaller (1.0%) and slower (1.06 s) still. The proximity of pericyte somata did not predict capillary dilation amplitude. Expression of the contractile protein ␣-smooth muscle actin was high in arterioles and low in capillaries. Unexpectedly, we found that blood flow in the three vascular layers was differentially regulated. Flicker stimulation evoked far larger dilations and RBC flux increases in the intermediate layer capillaries than in the superficial and deep layer capillaries (2.6 vs 0.9 and 0.7% dilation; 25.7 vs 0.8 and 11.3% RBC flux increase). These results indicate that functional hyperemia in the retina is driven primarily by active dilation of arterioles. The dilation of intermediate layer capillaries is likely mediated by active mechanisms as well.
    [Show full text]
  • Non Invasive Based Patient Specific Simulation of Arteries Using Lumped Models
    International Journal of Radiology & Radiation Therapy Research Article Open Access Non invasive based patient specific simulation of arteries using lumped models Abstract Volume 3 Issue 6 - 2017 This Paper aims at non-invasive prediction of blood pressures and velocities in Bhavya Sambana,1 Kiran Kumar Y,2 Prasad arteries at any part of the body given the entire physical network of the artery and 2 the blood pressure and velocity values at another point in the artery by constructing RV 1Department of Electrical Engineering, India the analogous electrical circuit using Windkessel Models. Solving the circuit thus 2Philips Research, India obtained gives blood velocities and also blood pressures at different segments of the artery. These lumped electrical models are validated with ultrasound images of the Correspondence: Kiran Kumar Y, Department of Electrical carotid artery of different patients. Through this method, we can measure the blood Engineering, IIT Madras, Chennai, India, velocities and blood pressures in difficult places like brain where much complexity is Email [email protected] involved to find the velocities and only the physical network can be found. With the help of these measured values, we can predict rupture of aneurysms using predictive Received: April 15, 2017 | Published: August 09, 2017 modeling. Keywords: windkessel, carotid artery, ultrasound, aneurysms Introduction filled with water except for a pocket of air. As the water is pumped, water compresses the air in the pocket and pushes water out of the Currently, there are no methods available for non-invasive chamber, which circulates back to the chamber. This is in analogy with measurement of both blood pressures and velocities through the functioning of the heart.
    [Show full text]
  • Design and Evaluation of Enhanced Mock Circulatory Platform Simulating Cardiovascular Physiology for Medical Palpation Training
    applied sciences Article Design and Evaluation of Enhanced Mock Circulatory Platform Simulating Cardiovascular Physiology for Medical Palpation Training Jae-Hak Jeong 1 , Young-Min Kim 2, Bomi Lee 1 , Junki Hong 1 , Jaeuk Kim 2 , Sam-Yong Woo 3 , Tae-Heon Yang 4,* and Yong-Hwa Park 1,* 1 Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Korea; [email protected] (J.-H.J.); [email protected] (B.L.); [email protected] (J.H.) 2 Future Medicine Division, Korea Institute of Oriental Medicine, 1672 Yuseong-daero, Yuseong-gu, Daejeon 34054, Korea; [email protected] (Y.-M.K.); [email protected] (J.K.) 3 Center for Mechanical Metrology, Division of Physical Metrology, Korea Research Institute of Standards and Science, 267 Gajeong-ro, Yuseong-gu, Daejeon 34113, Korea; [email protected] 4 School of Electronic and Electrical Engineering, College of Convergence Technology, Korea National University of Transportation, 50 Daehak-ro, Daesowon-myeon, Chungcheongbuk-do, Chungju-si 27469, Korea * Correspondence: [email protected] (T.-H.Y.); [email protected] (Y.-H.P.); Tel.: +82-43-841-5324 (T.-H.Y.); +82-42-350-3235 (Y.-H.P.) Received: 4 July 2020; Accepted: 3 August 2020; Published: 6 August 2020 Abstract: This study presents a design and evaluation of a mock circulatory platform, which can reproduce blood pressure and its waveforms to provide palpation experience based on the human cardiovascular physiology. To reproduce the human cardiovascular behavior, especially the blood pressure, the proposed platform includes three major modules: heart, artery and reservoir modules.
    [Show full text]
  • Bases of Human Factors Engineering/ Ergonomics
    Engineering Physiology Fourth Edition Karl H.E. Kroemer · Hiltrud J. Kroemer · Katrin E. Kroemer-Elbert Engineering Physiology Bases of Human Factors Engineering/Ergonomics Fourth Edition 123 Karl H.E. Kroemer Hiltrud J. Kroemer 3624 Laurel Drive 3624 Laurel Drive 24060-8562 Blacksburg, VA 24060-8562 Blacksburg, VA Virginia Virginia USA USA [email protected] [email protected] Katrin E. Kroemer-Elbert 133 St. Paul Street 07090-2144 Westfield, NJ USA [email protected] ISBN 978-3-642-12882-0 e-ISBN 978-3-642-12883-7 DOI 10.1007/978-3-642-12883-7 Springer Heidelberg Dordrecht London New York Library of Congress Control Number: 2010930424 3rd edition: © VNR (now Wiley) 1997 © Springer-Verlag Berlin Heidelberg 1986, 1990, 2010 This work is subject to copyright. All rights are reserved, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilm or in any other way, and storage in data banks. Duplication of this publication or parts thereof is permitted only under the provisions of the German Copyright Law of September 9, 1965, in its current version, and permission for use must always be obtained from Springer. Violations are liable to prosecution under the German Copyright Law. The use of general descriptive names, registered names, trademarks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. Cover design: WMXDesign GmbH, Heidelberg Printed on acid-free paper Springer is part of Springer Science+Business Media (www.springer.com) A Few Words at the Beginning Gunther Lehmann published his book “Practical Work Physiology” (Praktische Arbeitsphysiologie, Stuttgart, Thieme) in 1953.
    [Show full text]