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Baranger J, Villemain O, Goudot G, Dizeux A, Le Blay H, Mirault T, Messas E, Pernot M, Tanter M. The fundamental mechanisms of the Korotkoff sounds generation. SCIENCE ADVANCES 2023; 9:eadi4252. [PMID: 37792931 PMCID: PMC10550233 DOI: 10.1126/sciadv.adi4252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 09/05/2023] [Indexed: 10/06/2023]
Abstract
Blood pressure measurement is the most widely performed clinical exam to predict mortality risk. The gold standard for its noninvasive assessment is the auscultatory method, which relies on listening to the so-called "Korotkoff sounds" in a stethoscope placed at the outlet of a pneumatic arm cuff. However, more than a century after their discovery, the origin of these sounds is still debated, which implies a number of clinical limitations. We imaged the Korotkoff sound generation in vivo at thousands of images per second using ultrafast ultrasound. We showed with both experience and theory that Korotkoff sounds are paradoxically not sound waves emerging from the brachial artery but rather shear vibrations conveyed in surrounding tissues by the nonlinear pulse wave propagation. When these shear vibrations reached the stethoscope, they were synchronous, correlated, and comparable in intensity with the Korotkoff sounds. Understanding this mechanism could ultimately improve blood pressure measurement and provide additional understanding of arterial mechanical properties.
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Affiliation(s)
- Jerome Baranger
- Physics for Medicine Paris, Inserm, ESPCI PSL Paris, CNRS, Paris, France
| | - Olivier Villemain
- Physics for Medicine Paris, Inserm, ESPCI PSL Paris, CNRS, Paris, France
| | - Guillaume Goudot
- Physics for Medicine Paris, Inserm, ESPCI PSL Paris, CNRS, Paris, France
- Université Paris Cité, Inserm UMR 970, PARCC, Vascular Medicine Department, Hôpital Européen Georges-Pompidou, Assistance Publique Hôpitaux de Paris, Paris, France
| | - Alexandre Dizeux
- Physics for Medicine Paris, Inserm, ESPCI PSL Paris, CNRS, Paris, France
| | - Heiva Le Blay
- Physics for Medicine Paris, Inserm, ESPCI PSL Paris, CNRS, Paris, France
| | - Tristan Mirault
- Université Paris Cité, Inserm UMR 970, PARCC, Vascular Medicine Department, Hôpital Européen Georges-Pompidou, Assistance Publique Hôpitaux de Paris, Paris, France
| | - Emmanuel Messas
- Université Paris Cité, Inserm UMR 970, PARCC, Vascular Medicine Department, Hôpital Européen Georges-Pompidou, Assistance Publique Hôpitaux de Paris, Paris, France
| | - Mathieu Pernot
- Physics for Medicine Paris, Inserm, ESPCI PSL Paris, CNRS, Paris, France
| | - Mickael Tanter
- Physics for Medicine Paris, Inserm, ESPCI PSL Paris, CNRS, Paris, France
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Ganizada BH, Reesink KD, Parikh S, Ramaekers MJFG, Akbulut AC, Saraber PJMH, Debeij GP, Jaminon AM, Natour E, Lorusso R, Wildberger JE, Mees B, Schurink GW, Jacobs MJ, Cleutjens J, Krapels I, Gombert A, Maessen JG, Accord R, Delhaas T, Schalla S, Schurgers LJ, Bidar E. The Maastricht Acquisition Platform for Studying Mechanisms of Cell-Matrix Crosstalk (MAPEX): An Interdisciplinary and Systems Approach towards Understanding Thoracic Aortic Disease. Biomedicines 2023; 11:2095. [PMID: 37626592 PMCID: PMC10452257 DOI: 10.3390/biomedicines11082095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 07/20/2023] [Accepted: 07/21/2023] [Indexed: 08/27/2023] Open
Abstract
Current management guidelines for ascending thoracic aortic aneurysms (aTAA) recommend intervention once ascending or sinus diameter reaches 5-5.5 cm or shows a growth rate of >0.5 cm/year estimated from echo/CT/MRI. However, many aTAA dissections (aTAAD) occur in vessels with diameters below the surgical intervention threshold of <55 mm. Moreover, during aTAA repair surgeons observe and experience considerable variations in tissue strength, thickness, and stiffness that appear not fully explained by patient risk factors. To improve the understanding of aTAA pathophysiology, we established a multi-disciplinary research infrastructure: The Maastricht acquisition platform for studying mechanisms of tissue-cell crosstalk (MAPEX). The explicit scientific focus of the platform is on the dynamic interactions between vascular smooth muscle cells and extracellular matrix (i.e., cell-matrix crosstalk), which play an essential role in aortic wall mechanical homeostasis. Accordingly, we consider pathophysiological influences of wall shear stress, wall stress, and smooth muscle cell phenotypic diversity and modulation. Co-registrations of hemodynamics and deep phenotyping at the histological and cell biology level are key innovations of our platform and are critical for understanding aneurysm formation and dissection at a fundamental level. The MAPEX platform enables the interpretation of the data in a well-defined clinical context and therefore has real potential for narrowing existing knowledge gaps. A better understanding of aortic mechanical homeostasis and its derangement may ultimately improve diagnostic and prognostic possibilities to identify and treat symptomatic and asymptomatic patients with existing and developing aneurysms.
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Affiliation(s)
- Berta H. Ganizada
- Departments of Cardiothoracic Surgery, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands; (B.H.G.)
- Department of Biochemistry, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Koen D. Reesink
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Shaiv Parikh
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Mitch J. F. G. Ramaekers
- Department of Radiology and Nuclear Medicine, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
- Department of Cardiology, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Asim C. Akbulut
- Department of Biochemistry, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
- Stem Cell Research University Maastricht Facility, 6229 ER Maastricht, The Netherlands
| | - Pepijn J. M. H. Saraber
- Department of Biochemistry, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Gijs P. Debeij
- Departments of Cardiothoracic Surgery, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands; (B.H.G.)
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - MUMC-TAA Student Team
- Departments of Cardiothoracic Surgery, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands; (B.H.G.)
| | - Armand M. Jaminon
- Department of Biochemistry, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Ehsan Natour
- Departments of Cardiothoracic Surgery, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands; (B.H.G.)
| | - Roberto Lorusso
- Departments of Cardiothoracic Surgery, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands; (B.H.G.)
| | - Joachim E. Wildberger
- Department of Radiology and Nuclear Medicine, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Barend Mees
- Department of Vascular Surgery, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Geert Willem Schurink
- Department of Vascular Surgery, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Michael J. Jacobs
- Department of Vascular Surgery, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Jack Cleutjens
- Department of Pathology, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Ingrid Krapels
- Department of Clinical Genetics, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Alexander Gombert
- Department of Vascular Surgery, University Hospital RWTH Aachen, 52074 Aachen, Germany
| | - Jos G. Maessen
- Departments of Cardiothoracic Surgery, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands; (B.H.G.)
| | - Ryan Accord
- Department of Cardiothoracic Surgery, Center for Congenital Heart Diseases, University Medical Center Groningen, 9713 GZ Groningen, The Netherlands
| | - Tammo Delhaas
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Simon Schalla
- Department of Radiology and Nuclear Medicine, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
- Department of Cardiology, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
| | - Leon J. Schurgers
- Department of Biochemistry, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands
- Stem Cell Research University Maastricht Facility, 6229 ER Maastricht, The Netherlands
- Institute of Experimental Medicine and Systems Biology, RWTH Aachen University, 52074 Aachen, Germany
| | - Elham Bidar
- Departments of Cardiothoracic Surgery, CARIM School for Cardiovascular Diseases, Heart and Vascular Center, Maastricht University Medical Center (MUMC+), 6229 ER Maastricht, The Netherlands; (B.H.G.)
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Giudici A, Palombo C, Kozakova M, Morizzo C, Cruickshank JK, Khir AW. Subject-Specific Pressure Normalization of Local Pulse Wave Velocity: Separating Intrinsic From Acute Load-Dependent Stiffening in Hypertensive Patients. Front Physiol 2022; 12:783457. [PMID: 35242043 PMCID: PMC8886155 DOI: 10.3389/fphys.2021.783457] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Accepted: 12/14/2021] [Indexed: 11/21/2022] Open
Abstract
Pulse wave velocity (PWV) is a powerful predictor of cardiovascular events. However, its intrinsic blood pressure (BP)-dependency complicates distinguishing between acute and chronic effects of increased BP on arterial stiffness. Based on the assumption that arteries exhibit a nearly exponential pressure-area (P-A) relationship, this study proposes a method to assess intersubject differences in local PWV independently from BP. The method was then used to analyze differences in local carotid PWV (cPWV) between hypertensive and healthy normotensive people before and after BP-normalization. Pressure (P) and diameter (D) waveforms were simultaneously acquired via tonometer at the left and ultrasound scanning at right common carotid artery (CCA), respectively, in 22 patients with Grade 1 or 2 hypertension and 22 age- and sex-matched controls. cPWV was determined using the D2P-loop method. Then, the exponential modeling of the P-area (A = πD2/4) relationships allowed defining a mathematical formulation to compute subject-specific changes in cPWV associated with BP changes, thus enabling the normalization of cPWV against intersubject differences in BP at the time of measurement. Carotid systolic BP (SBP) and diastolic BP (DBP) were, on average, 17.7 (p < 0.001) and 8.9 mmHg (p < 0.01) higher in hypertensives than controls, respectively. cPWV was 5.56 ± 0.86 m/s in controls and 6.24 ± 1.22 m/s in hypertensives. BP alone accounted for 68% of the cPWV difference between the two groups: 5.80 ± 0.84 vs. 6.03 ± 1.07 m/s after BP-normalization (p = 0.47). The mechanistic normalization of cPWV was in agreement with that estimated by analysis of covariance (ANCOVA). In conclusion, the proposed method, which could be easily implemented in the clinical setting, allows to assess the intersubject differences in PWV independently of BP. Our results suggested that mild hypertension in middle-aged subjects without target organ damage does not significantly alter the stiffness of the CCA wall independently of acute differences in BP. The results warrant further clinical investigations to establish the potential clinical utility of the method.
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Affiliation(s)
- Alessandro Giudici
- Brunel Institute for Bioengineering, Brunel University London, Uxbridge, United Kingdom
| | - Carlo Palombo
- Department of Surgical, Medical, Molecular Pathology and Critical Area Medicine, University of Pisa, Pisa, Italy
| | - Michaela Kozakova
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Carmela Morizzo
- Department of Surgical, Medical, Molecular Pathology and Critical Area Medicine, University of Pisa, Pisa, Italy
| | - J Kennedy Cruickshank
- School of Life-Course/Nutritional Sciences, King's College, St. Thomas' and Guy's Hospitals, London, United Kingdom
| | - Ashraf W Khir
- Brunel Institute for Bioengineering, Brunel University London, Uxbridge, United Kingdom
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van der Laan KWF, Reesink KD, van der Bruggen MM, Jaminon AMG, Schurgers LJ, Megens RTA, Huberts W, Delhaas T, Spronck B. Improved Quantification of Cell Density in the Arterial Wall-A Novel Nucleus Splitting Approach Applied to 3D Two-Photon Laser-Scanning Microscopy. Front Physiol 2022; 12:814434. [PMID: 35095571 PMCID: PMC8790070 DOI: 10.3389/fphys.2021.814434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Accepted: 12/13/2021] [Indexed: 12/05/2022] Open
Abstract
Accurate information on vascular smooth muscle cell (VSMC) content, orientation, and distribution in blood vessels is indispensable to increase understanding of arterial remodeling and to improve modeling of vascular biomechanics. We have previously proposed an analysis method to automatically characterize VSMC orientation and transmural distribution in murine carotid arteries under well-controlled biomechanical conditions. However, coincident nuclei, erroneously detected as one large nucleus, were excluded from the analysis, hampering accurate VSMC content characterization and distorting transmural distributions. In the present study, therefore, we aim to (1) improve the previous method by adding a "nucleus splitting" procedure to split coinciding nuclei, (2) evaluate the accuracy of this novel method, and (3) test this method in a mouse model of VSMC apoptosis. After euthanasia, carotid arteries from SM22α-hDTR Apoe -/- and control Apoe -/- mice were bluntly dissected, excised, mounted in a biaxial biomechanical tester and brought to in vivo axial stretch and a pressure of 100 mmHg. Nuclei and elastin fibers were then stained using Syto-41 and Eosin-Y, respectively, and imaged using 3D two-photon laser scanning microscopy. Nuclei were segmented from images and coincident nuclei were split. The nucleus splitting procedure determines the likelihood that voxel pairs within coincident nuclei belong to the same nucleus and utilizes these likelihoods to identify individual nuclei using spectral clustering. Manual nucleus counts were used as a reference to assess the performance of our splitting procedure. Before and after splitting, automatic nucleus counts differed -26.6 ± 9.90% (p < 0.001) and -1.44 ± 7.05% (p = 0.467) from the manual reference, respectively. Whereas the slope of the relative difference between the manual and automated counts as a function of the manual count was significantly negative before splitting (p = 0.008), this slope became insignificant after splitting (p = 0.653). Smooth muscle apoptosis led to a 33.7% decrease in VSMC density (p = 0.008). Nucleus splitting improves the accuracy of automated cell content quantification in murine carotid arteries and overcomes the progressively worsening problem of coincident nuclei with increasing cell content in vessels. The presented image analysis framework provides a robust tool to quantify cell content, orientation, shape, and distribution in vessels to inform experimental and advanced computational studies on vascular structure and function.
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Affiliation(s)
- Koen W. F. van der Laan
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, Netherlands
| | - Koen D. Reesink
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, Netherlands
| | - Myrthe M. van der Bruggen
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, Netherlands
| | - Armand M. G. Jaminon
- Department of Biochemistry, CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, Netherlands
| | - Leon J. Schurgers
- Department of Biochemistry, CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, Netherlands
| | - Remco T. A. Megens
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, Netherlands
- Institute for Cardiovascular Prevention, Ludwig Maximilian University, Munich, Germany
- German Center for Cardiovascular Research (DZHK), Partner Site Munich Heart Alliance, Munich, Germany
| | - Wouter Huberts
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, Netherlands
| | - Tammo Delhaas
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, Netherlands
| | - Bart Spronck
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, Netherlands
- Department of Biomedical Engineering, School of Engineering and Applied Science, Yale University, New Haven, CT, United States
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Qu G, Zhang Z, Zhu H. Association Between Blood Pressure Control and Arterial Stiffness in Middle-Aged and Elderly Chinese Patients with Hypertension. Med Sci Monit 2021; 27:e931414. [PMID: 34420028 PMCID: PMC8388207 DOI: 10.12659/msm.931414] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Background The severity of arterial stiffness can be evaluated by pulse wave velocity (PWV). This study investigated the association between blood pressure (BP) control and arterial stiffness in middle-aged and elderly Chinese patients with hypertension. Material/Methods Three hundred and twelve hypertensive patients were divided according to whether their hypertension was well-controlled or uncontrolled and stratified according to age. Arterial stiffness was evaluated by brachial-ankle pulse wave velocity (baPWV). The effect of BP control on arterial stiffness and its severity was assessed by multivariate linear and logistic regression analyses. Results Moderate and severe arterial stiffness was detected significantly more often in patients with uncontrolled hypertension than in those with well-controlled hypertension, regardless of age. BaPWV increased by 8.467 cm/s in the study population overall for every 1-mmHg increment in systolic BP and by 8.584, 8.616, and 8.199 cm/s, respectively, in patients aged 45–65, 65–80, and ≥80 years. Regardless of age, the risk of arterial stiffness was 5.93 times higher (95% confidence interval 2.78–12.64) and the risk of a one-grade increase in the severity of arterial stiffness was 4.01 times higher (95% confidence interval 2.51–6.42) in patients with uncontrolled hypertension than in those with well-controlled hypertension. Conclusions This study found a positive relationship between baPWV and BP and identified uncontrolled BP as a risk factor for arterial stiffness and its severity. Management of BP within a reasonable range may help to ameliorate arterial stiffness.
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Affiliation(s)
- Geyue Qu
- Department of Geriatrics, Xuanwu Hospital, Capital Medical University, Beijing, China (mainland)
| | - Zhongying Zhang
- Department of Geriatrics, Xuanwu Hospital, Capital Medical University, Beijing, China (mainland)
| | - Hong Zhu
- Department of Geriatrics, Xuanwu Hospital, Capital Medical University, Beijing, China (mainland)
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van der Bruggen M, Spronck B, Bos S, Heusinkveld MHG, Taddei S, Ghiadoni L, Delhaas T, Bruno RM, Reesink KD. Pressure-Corrected Carotid Stiffness and Young's Modulus: Evaluation in an Outpatient Clinic Setting. Am J Hypertens 2021; 34:737-743. [PMID: 33564865 PMCID: PMC8351507 DOI: 10.1093/ajh/hpab028] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 01/26/2021] [Accepted: 01/29/2021] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Conventional measures for assessing arterial stiffness are inherently pressure dependent. Whereas statistical pressure adjustment is feasible in (larger) populations, it is unsuited for the evaluation of an individual patient. Moreover, statistical "correction" for blood pressure may actually correct for: (i) the acute dependence of arterial stiffness on blood pressure at the time of measurement; and/or (ii) the remodeling effect that blood pressure (hypertension) may have on arterial stiffness, but it cannot distinguish between these processes. METHODS We derived-assuming a single-exponential pressure-diameter relationship-3 theoretically pressure-independent carotid stiffness measures suited for individual patient evaluation: (i) stiffness index β0, (ii) pressure-corrected carotid pulse wave velocity (cPWVcorr), and (iii) pressure-corrected Young's modulus (Ecorr). Using linear regression analysis, we evaluated in a sample of the CATOD study cohort changes in mean arterial pressure (ΔMAP) and comparatively the changes in the novel (Δβ0, ΔcPWVcorr, and ΔEcorr) as well as conventional (ΔcPWV and ΔE) stiffness measures after a 2.9 ± 1.0-year follow-up. RESULTS We found no association between ΔMAP and Δβ0, ΔcPWVcorr, or ΔEcorr. In contrast, we did find a significant association between ΔMAP and conventional measures ΔcPWV and ΔE. Additional adjustments for biomechanical confounders and traditional risk factors did neither materially change these associations nor the lack thereof. CONCLUSIONS Our newly proposed pressure-independent carotid stiffness measures avoid the need for statistical correction. Hence, these measures (β0, cPWVcorr, and Ecorr) can be used in a clinical setting for (i) patient-specific risk assessment and (ii) investigation of potential remodeling effects of (changes in) blood pressure on intrinsic arterial stiffness.
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Affiliation(s)
- Myrthe van der Bruggen
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University Medical Centre (MUMC+), Maastricht, The Netherlands
| | - Bart Spronck
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University Medical Centre (MUMC+), Maastricht, The Netherlands
- Department of Biomedical Engineering, School of Engineering & Applied Science, Yale University, New Haven, Connecticut, USA
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, New South Wales, Australia
| | - Siske Bos
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University Medical Centre (MUMC+), Maastricht, The Netherlands
| | - Maarten H G Heusinkveld
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University Medical Centre (MUMC+), Maastricht, The Netherlands
| | - Stefano Taddei
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Lorenzo Ghiadoni
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Tammo Delhaas
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University Medical Centre (MUMC+), Maastricht, The Netherlands
| | - Rosa Maria Bruno
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
- Institute of Clinical Physiology—CNR, Pisa, Italy
| | - Koen D Reesink
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University Medical Centre (MUMC+), Maastricht, The Netherlands
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7
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Gade JL, Thore CJ, Sonesson B, Stålhand J. In vivo parameter identification in arteries considering multiple levels of smooth muscle activity. Biomech Model Mechanobiol 2021; 20:1547-1559. [PMID: 33934232 PMCID: PMC8298368 DOI: 10.1007/s10237-021-01462-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 04/16/2021] [Indexed: 11/25/2022]
Abstract
In this paper an existing in vivo parameter identification method for arteries is extended to account for smooth muscle activity. Within this method a continuum-mechanical model, whose parameters relate to the mechanical properties of the artery, is fit to clinical data by solving a minimization problem. Including smooth muscle activity in the model increases the number of parameters. This may lead to overparameterization, implying that several parameter combinations solve the minimization problem equally well and it is therefore not possible to determine which set of parameters represents the mechanical properties of the artery best. To prevent overparameterization the model is fit to clinical data measured at different levels of smooth muscle activity. Three conditions are considered for the human abdominal aorta: basal during rest; constricted, induced by lower-body negative pressure; and dilated, induced by physical exercise. By fitting the model to these three arterial conditions simultaneously a unique set of model parameters is identified and the model prediction agrees well with the clinical data.
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Affiliation(s)
- Jan-Lucas Gade
- Department of Management and Engineering, Division of Solid Mechanics, Linköping University, Linköping, Sweden.
| | - Carl-Johan Thore
- Department of Management and Engineering, Division of Solid Mechanics, Linköping University, Linköping, Sweden
| | - Björn Sonesson
- Department of Cardiothoracic and Vascular Surgery, Skåne University Hospital, Malmö, Sweden
| | - Jonas Stålhand
- Department of Management and Engineering, Division of Solid Mechanics, Linköping University, Linköping, Sweden
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8
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van der Bruggen MM, Reesink KD, Spronck PJM, Bitsch N, Hameleers J, Megens RTA, Schalkwijk CG, Delhaas T, Spronck B. An integrated set-up for ex vivo characterisation of biaxial murine artery biomechanics under pulsatile conditions. Sci Rep 2021; 11:2671. [PMID: 33514757 PMCID: PMC7846753 DOI: 10.1038/s41598-021-81151-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 12/07/2020] [Indexed: 01/19/2023] Open
Abstract
Ex vivo characterisation of arterial biomechanics enables detailed discrimination of the various cellular and extracellular contributions to arterial stiffness. However, ex vivo biomechanical studies are commonly performed under quasi-static conditions, whereas dynamic biomechanical behaviour (as relevant in vivo) may differ substantially. Hence, we aim to (1) develop an integrated set-up for quasi-static and dynamic biaxial biomechanical testing, (2) quantify set-up reproducibility, and (3) illustrate the differences in measured arterial stiffness between quasi-static and dynamic conditions. Twenty-two mouse carotid arteries were mounted between glass micropipettes and kept fully vasodilated. While recording pressure, axial force (F), and inner diameter, arteries were exposed to (1) quasi-static pressure inflation from 0 to 200 mmHg; (2) 300 bpm dynamic pressure inflation (peaking at 80/120/160 mmHg); and (3) axial stretch (λz) variation at constant pressures of 10/60/100/140/200 mmHg. Measurements were performed in duplicate. Single-point pulse wave velocities (PWV; Bramwell-Hill) and axial stiffness coefficients (cax = dF/dλz) were calculated at the in vivo value of λz. Within-subject coefficients of variation were ~ 20%. Dynamic PWVs were consistently higher than quasi-static PWVs (p < 0.001); cax increased with increasing pressure. We demonstrated the feasibility of ex vivo biomechanical characterisation of biaxially-loaded murine carotid arteries under pulsatile conditions, and quantified reproducibility allowing for well-powered future study design.
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Affiliation(s)
- Myrthe M van der Bruggen
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, Universiteitssingel 50, Room 3.359, 6229ER, Maastricht, The Netherlands
| | - Koen D Reesink
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, Universiteitssingel 50, Room 3.359, 6229ER, Maastricht, The Netherlands
| | | | - Nicole Bitsch
- Muroidean Facility, CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, The Netherlands
| | - Jeroen Hameleers
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, Universiteitssingel 50, Room 3.359, 6229ER, Maastricht, The Netherlands
| | - Remco T A Megens
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, Universiteitssingel 50, Room 3.359, 6229ER, Maastricht, The Netherlands.,Institute for Cardiovascular Prevention, Ludwig-Maximilians-Universität, Munich, Germany
| | - Casper G Schalkwijk
- Department of Internal Medicine, CARIM School for Cardiovascular Diseases, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Tammo Delhaas
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, Universiteitssingel 50, Room 3.359, 6229ER, Maastricht, The Netherlands
| | - Bart Spronck
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, Universiteitssingel 50, Room 3.359, 6229ER, Maastricht, The Netherlands. .,Department of Biomedical Engineering, School of Engineering & Applied Science, Yale University, New Haven, CT, USA.
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9
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Pucci G, Spronck B, Avolio AP, Tap L, Vaudo G, Anastasio F, Van Den Meiracker A, Mattace-Raso F. Age-Specific Acute Changes in Carotid-Femoral Pulse Wave Velocity With Head-up Tilt. Am J Hypertens 2020; 33:1112-1118. [PMID: 32634245 PMCID: PMC7814224 DOI: 10.1093/ajh/hpaa101] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 06/25/2020] [Accepted: 07/06/2020] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND Aortic stiffness as measured by carotid-femoral pulse wave velocity (cfPWV) is known to depend on blood pressure (BP), and this dependency may change with age. Therefore, the hydrostatic BP gradient resulting from a change in body posture may elicit a cfPWV change that is age-dependent. We aimed to analyze the relationship between BP gradient-induced by head-up body tilting-and related changes in cfPWV in individuals of varying age. METHODS cfPWV and other hemodynamic parameters were measured in 30 healthy individuals at a head-up tilt of 0° (supine), 30°, and 60°. At each angle, the PWV gradient and resulting cfPWV were also estimated (predicted) by assuming a global nonlinear, exponential, pressure-diameter relationship characterized by a constant β0, and taking into account that (diastolic) foot-to-foot cfPWV acutely depends on diastolic BP. RESULTS cfPWV significantly increased upon body tilting (8.0 ± 2.0 m/s supine, 9.1 ± 2.6 m/s at 30°, 9.5 ± 3.2 m/s at 60°, P for trend <0.01); a positive trend was also observed for heart rate (HR; P < 0.01). When the observed, tilt-induced cfPWV change measured by applanation tonometry was compared with that predicted from the estimated BP hydrostatic gradient, the difference in observed-vs.-predicted PWV change increased nonlinearly as a function of age (R2 for quadratic trend = 0.38, P < 0.01, P vs. linear = 0.04). This result was unaffected by HR tilt-related variations (R2 for quadratic trend = 0.37, P < 0.01, P vs. linear = 0.04). CONCLUSIONS Under a hydrostatic pressure gradient, the pulse wave traveling along the aorta undergoes an age-related, nonlinear PWV increase exceeding the increase predicted from BP dependency.
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Affiliation(s)
- Giacomo Pucci
- Department of Medicine, University of Perugia, Unit of Internal Medicine, Terni University Hospital, Terni, Italy
- Department of Internal Medicine, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | - Bart Spronck
- Department of Biomedical Engineering, Yale University, New Haven, Connecticut, USA
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, The Netherlands
| | - Alberto P Avolio
- Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
| | - Lisanne Tap
- Department of Internal Medicine, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | - Gaetano Vaudo
- Department of Medicine, University of Perugia, Unit of Internal Medicine, Terni University Hospital, Terni, Italy
| | - Fabio Anastasio
- Unit of Cardiology, ASST-VAL Hospital of Sondrio, Sondrio, Italy
| | - Anton Van Den Meiracker
- Department of Internal Medicine, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | - Francesco Mattace-Raso
- Department of Internal Medicine, Erasmus MC University Medical Center, Rotterdam, The Netherlands
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10
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Jaminon A, Reesink K, Kroon A, Schurgers L. The Role of Vascular Smooth Muscle Cells in Arterial Remodeling: Focus on Calcification-Related Processes. Int J Mol Sci 2019; 20:E5694. [PMID: 31739395 PMCID: PMC6888164 DOI: 10.3390/ijms20225694] [Citation(s) in RCA: 151] [Impact Index Per Article: 30.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 10/31/2019] [Accepted: 11/08/2019] [Indexed: 12/22/2022] Open
Abstract
Arterial remodeling refers to the structural and functional changes of the vessel wall that occur in response to disease, injury, or aging. Vascular smooth muscle cells (VSMC) play a pivotal role in regulating the remodeling processes of the vessel wall. Phenotypic switching of VSMC involves oxidative stress-induced extracellular vesicle release, driving calcification processes. The VSMC phenotype is relevant to plaque initiation, development and stability, whereas, in the media, the VSMC phenotype is important in maintaining tissue elasticity, wall stress homeostasis and vessel stiffness. Clinically, assessment of arterial remodeling is a challenge; particularly distinguishing intimal and medial involvement, and their contributions to vessel wall remodeling. The limitations pertain to imaging resolution and sensitivity, so methodological development is focused on improving those. Moreover, the integration of data across the microscopic (i.e., cell-tissue) and macroscopic (i.e., vessel-system) scale for correct interpretation is innately challenging, because of the multiple biophysical and biochemical factors involved. In the present review, we describe the arterial remodeling processes that govern arterial stiffening, atherosclerosis and calcification, with a particular focus on VSMC phenotypic switching. Additionally, we review clinically applicable methodologies to assess arterial remodeling and the latest developments in these, seeking to unravel the ubiquitous corroborator of vascular pathology that calcification appears to be.
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Affiliation(s)
- Armand Jaminon
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, 6229 ER Maastricht, The Netherlands;
| | - Koen Reesink
- Department of Biomedical Engineering, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, 6229 ER Maastricht, The Netherlands;
| | - Abraham Kroon
- Department of Internal Medicine, Maastricht University Medical Centre (MUMC+), 6229 HX Maastricht, The Netherlands;
| | - Leon Schurgers
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, 6229 ER Maastricht, The Netherlands;
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11
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Emuna N, Durban D, Osovski S. Sensitivity of Arterial Hyperelastic Models to Uncertainties in Stress-Free Measurements. J Biomech Eng 2019; 140:2683233. [PMID: 30029245 DOI: 10.1115/1.4040400] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Indexed: 12/14/2022]
Abstract
Despite major advances made in modeling vascular tissue biomechanics, the predictive power of constitutive models is still limited by uncertainty of the input data. Specifically, key measurements, like the geometry of the stress-free (SF) state, involve a definite, sometimes non-negligible, degree of uncertainty. Here, we introduce a new approach for sensitivity analysis of vascular hyperelastic constitutive models to uncertainty in SF measurements. We have considered two vascular hyperelastic models: the phenomenological Fung model and the structure-motivated Holzapfel-Gasser-Ogden (HGO) model. Our results indicate up to 160% errors in the identified constitutive parameters for a 5% measurement uncertainty in the SF data. Relative margins of errors of up to 30% in the luminal pressure, 36% in the axial force, and over 200% in the stress predictions were recorded for 10% uncertainties. These findings are relevant to the large body of studies involving experimentally based modeling and analysis of vascular tissues. The impact of uncertainties on calibrated constitutive parameters is significant in context of studies that use constitutive parameters to draw conclusions about the underlying microstructure of vascular tissues, their growth and remodeling processes, and aging and disease states. The propagation of uncertainties into the predictions of biophysical parameters, e.g., force, luminal pressure, and wall stresses, is of practical importance in the design and execution of clinical devices and interventions. Furthermore, insights provided by the present findings may lead to more robust parameters identification techniques, and serve as selection criteria in the trade-off between model complexity and sensitivity.
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Affiliation(s)
- Nir Emuna
- Faculty of Aerospace Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel e-mail:
| | - David Durban
- Faculty of Aerospace Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel e-mail:
| | - Shmuel Osovski
- Faculty of Mechanical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel e-mail:
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12
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Determination of the Material Parameters in the Holzapfel-Gasser-Ogden Constitutive Model for Simulation of Age-Dependent Material Nonlinear Behavior for Aortic Wall Tissue under Uniaxial Tension. APPLIED SCIENCES-BASEL 2019. [DOI: 10.3390/app9142851] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
In this study, computational simulations and experiments were performed to investigate the mechanical behavior of the aorta wall because of the increasing occurrences of aorta-related diseases. The study focused on the deformation and strength of porcine and healthy human abdominal aortic tissues under uniaxial tensile loading. The experiments for the mechanical behavior of the arterial tissue were conducted using a uniaxial tensile test apparatus to validate the simulation results. In addition, the strength and stretching of the tissues in the abdominal aorta of a healthy human as a function of age were investigated based on the uniaxial tensile tests. Moreover, computational simulations using the ABAQUS finite element analysis program were conducted on the experimental scenarios based on age, and the Holzapfel–Gasser–Ogden (HGO) model was applied during the simulation. The material parameters and formulae to be used in the HGO model were proposed to identify the failure stress and stretch correlation with age.
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13
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Reesink KD, Spronck B. Constitutive interpretation of arterial stiffness in clinical studies: a methodological review. Am J Physiol Heart Circ Physiol 2019; 316:H693-H709. [DOI: 10.1152/ajpheart.00388.2018] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Clinical assessment of arterial stiffness relies on noninvasive measurements of regional pulse wave velocity or local distensibility. However, arterial stiffness measures do not discriminate underlying changes in arterial wall constituent properties (e.g., in collagen, elastin, or smooth muscle), which is highly relevant for development and monitoring of treatment. In arterial stiffness in recent clinical-epidemiological studies, we systematically review clinical-epidemiological studies (2012–) that interpreted arterial stiffness changes in terms of changes in arterial wall constituent properties (63 studies included of 514 studies found). Most studies that did so were association studies (52 of 63 studies) providing limited causal evidence. Intervention studies (11 of 63 studies) addressed changes in arterial stiffness through the modulation of extracellular matrix integrity (5 of 11 studies) or smooth muscle tone (6 of 11 studies). A handful of studies (3 of 63 studies) used mathematical modeling to discriminate between extracellular matrix components. Overall, there exists a notable gap in the mechanistic interpretation of stiffness findings. In constitutive model-based interpretation, we first introduce constitutive-based modeling and use it to illustrate the relationship between constituent properties and stiffness measurements (“forward” approach). We then review all literature on modeling approaches for the constitutive interpretation of clinical arterial stiffness data (“inverse” approach), which are aimed at estimation of constitutive properties from arterial stiffness measurements to benefit treatment development and monitoring. Importantly, any modeling approach requires a tradeoff between model complexity and measurable data. Therefore, the feasibility of changing in vivo the biaxial mechanics and/or vascular smooth muscle tone should be explored. The effectiveness of modeling approaches should be confirmed using uncertainty quantification and sensitivity analysis. Taken together, constitutive modeling can significantly improve clinical interpretation of arterial stiffness findings.
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Affiliation(s)
- Koen D. Reesink
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, The Netherlands
| | - Bart Spronck
- Department of Biomedical Engineering, School of Engineering and Applied Science, Yale University, New Haven, Connecticut
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14
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Finite element simulation of three dimensional residual stress in the aortic wall using an anisotropic tissue growth model. J Mech Behav Biomed Mater 2019; 92:188-196. [PMID: 30738379 DOI: 10.1016/j.jmbbm.2019.01.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 11/16/2018] [Accepted: 01/09/2019] [Indexed: 11/19/2022]
Abstract
Residual stress is believed to play a significant role in the in vivo stress state of the arterial wall, but quantifying residual stress in vivo is challenging. Based on the well-known assumptions that residual stress is a result of heterogeneous arterial growth and that it homogenizes the transmural distribution of arterial wall stress, we propose a new anisotropic tissue growth model for the aorta to recover the three-dimensional residual stress field in a bi-layer human aortic wall. Finite element simulations showed that the predicted residual stress magnitude with this method are within the documented range for human aorta. Particularly, the homeostatic inter-layer stress difference is identified as a key parameter to quantify the opening angle. To the authors' knowledge, this is the first finite element study employing anisotropic growth of aortic tissue in a bi-layer model to generate three-dimensional residual stress field, and the resultant opening angle can match with the experiments. A parametric study found that inter-layer stress homogeneity, arterial blood pressure, axial pre-stretch, and material stiffness strongly affect the residual stress field.
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15
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Arterial stiffness index beta and cardio-ankle vascular index inherently depend on blood pressure but can be readily corrected. J Hypertens 2017; 35:98-104. [PMID: 27906838 DOI: 10.1097/hjh.0000000000001132] [Citation(s) in RCA: 88] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES Arterial stiffness index β and cardio-ankle vascular index (CAVI) are widely accepted to quantify the intrinsic exponent (β0) of the blood pressure (BP)-diameter relationship. CAVI and β assume an exponential relationship between pressure (P) and diameter (d). We aim to demonstrate that, under this assumption, β and CAVI as currently implemented are inherently BP-dependent and to provide corrected, BP-independent forms of CAVI and β. METHODS AND RESULTS In P = Prefe, usually reference pressure (Pref) and reference diameter (dref) are substituted with DBP and diastolic diameter to accommodate measurements. Consequently, the resulting exponent is not equal to the pressure-independent β0. CAVI does not only suffer from this 'reference pressure' effect, but also from the linear approximation of (dP/dd). For example, assuming β0 = 7, an increase of SBP/DBP from 110/70 to 170/120 mmHg increased β by 8.1% and CAVI by 14.3%. We derived corrected forms of β and of CAVI (CAVI0) that indeed did not change with BP and represent the pressure-independent β0. To substantiate the BP effect on CAVI in a typical follow-up study, we realistically simulated patients (n = 161) before and following BP-lowering 'treatment' (assuming no follow-up change in intrinsic β0 and therefore in actual P-d relationship). Lowering BP from 160 ± 14/111 ± 11 to 120 ± 15/79 ± 11 mmHg (p < 0.001) resulted in a significant CAVI decrease (from 8.1 ± 2.0 to 7.7 ± 2.1, p = 0.008); CAVI0 did not change (9.8 ± 2.4 and 9.9 ± 2.6, p = 0.499). CONCLUSION β and CAVI as currently implemented are inherently BP-dependent, potentially leading to erroneous conclusions in arterial stiffness trials. BP-independent forms are presented to readily overcome this problem.
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16
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Uncertainty quantification and sensitivity analysis of an arterial wall mechanics model for evaluation of vascular drug therapies. Biomech Model Mechanobiol 2017; 17:55-69. [PMID: 28755237 PMCID: PMC5807551 DOI: 10.1007/s10237-017-0944-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2017] [Accepted: 07/17/2017] [Indexed: 02/07/2023]
Abstract
Quantification of the uncertainty in constitutive model predictions describing arterial wall mechanics is vital towards non-invasive assessment of vascular drug therapies. Therefore, we perform uncertainty quantification to determine uncertainty in mechanical characteristics describing the vessel wall response upon loading. Furthermore, a global variance-based sensitivity analysis is performed to pinpoint measurements that are most rewarding to be measured more precisely. We used previously published carotid diameter–pressure and intima–media thickness (IMT) data (measured in triplicate), and Holzapfel–Gasser–Ogden models. A virtual data set containing 5000 diastolic and systolic diameter–pressure points, and IMT values was generated by adding measurement error to the average of the measured data. The model was fitted to single-exponential curves calculated from the data, obtaining distributions of constitutive parameters and constituent load bearing parameters. Additionally, we (1) simulated vascular drug treatment to assess the relevance of model uncertainty and (2) evaluated how increasing the number of measurement repetitions influences model uncertainty. We found substantial uncertainty in constitutive parameters. Simulating vascular drug treatment predicted a 6% point reduction in collagen load bearing (\documentclass[12pt]{minimal}
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\begin{document}$$L_\mathrm {coll}$$\end{document}Lcoll), approximately 50% of its uncertainty. Sensitivity analysis indicated that the uncertainty in \documentclass[12pt]{minimal}
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\begin{document}$$L_{\mathrm {coll}}$$\end{document}Lcoll could be decreased by 50% when increasing the number of measurement repetitions from 3 to 10. Model uncertainty, notably that in \documentclass[12pt]{minimal}
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\begin{document}$$L_{\mathrm {coll}}$$\end{document}Lcoll, could conceal effects of vascular drug therapy. However, this uncertainty could be reduced by increasing the number of measurement repetitions of distension and wall thickness measurements used for model parameterisation.
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17
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Bloksgaard M, Leurgans TM, Spronck B, Heusinkveld MHG, Thorsted B, Rosenstand K, Nissen I, Hansen UM, Brewer JR, Bagatolli LA, Rasmussen LM, Irmukhamedov A, Reesink KD, De Mey JGR. Imaging and modeling of acute pressure-induced changes of collagen and elastin microarchitectures in pig and human resistance arteries. Am J Physiol Heart Circ Physiol 2017; 313:H164-H178. [DOI: 10.1152/ajpheart.00110.2017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 03/30/2017] [Accepted: 04/14/2017] [Indexed: 01/15/2023]
Abstract
The impact of disease-related changes in the extracellular matrix (ECM) on the mechanical properties of human resistance arteries largely remains to be established. Resistance arteries from both pig and human parietal pericardium (PRA) display a different ECM microarchitecture compared with frequently used rodent mesenteric arteries. We hypothesized that the biaxial mechanics of PRA mirror pressure-induced changes in the ECM microarchitecture. This was tested using isolated pig PRA as a model system, integrating vital imaging, pressure myography, and mathematical modeling. Collagenase and elastase digestions were applied to evaluate the load-bearing roles of collagen and elastin, respectively. The incremental elastic modulus linearly related to the straightness of adventitial collagen fibers circumferentially and longitudinally (both R2 ≥ 0.99), whereas there was a nonlinear relationship to the internal elastic lamina elastin fiber branching angles. Mathematical modeling suggested a collagen recruitment strain (means ± SE) of 1.1 ± 0.2 circumferentially and 0.20 ± 0.01 longitudinally, corresponding to a pressure of ~40 mmHg, a finding supported by the vital imaging. The integrated method was tested on human PRA to confirm its validity. These showed limited circumferential distensibility and elongation and a collagen recruitment strain of 0.8 ± 0.1 circumferentially and 0.06 ± 0.02 longitudinally, reached at a distending pressure below 20 mmHg. This was confirmed by vital imaging showing negligible microarchitectural changes of elastin and collagen upon pressurization. In conclusion, we show here, for the first time in resistance arteries, a quantitative relationship between pressure-induced changes in the extracellular matrix and the arterial wall mechanics. The strength of the integrated methods invites for future detailed studies of microvascular pathologies. NEW & NOTEWORTHY This is the first study to quantitatively relate pressure-induced microstructural changes in resistance arteries to the mechanics of their wall. Principal findings using a pig model system were confirmed in human arteries. The combined methods provide a strong tool for future hypothesis-driven studies of microvascular pathologies.
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Affiliation(s)
- Maria Bloksgaard
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Thomas M. Leurgans
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Bart Spronck
- Department of Biomedical Engineering, Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands
| | - Maarten H. G. Heusinkveld
- Department of Biomedical Engineering, Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands
| | - Bjarne Thorsted
- MEMPHYS-Center for Biomembrane Physics, University of Southern Denmark, Odense, Denmark
| | - Kristoffer Rosenstand
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Inger Nissen
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Ulla M. Hansen
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Jonathan R. Brewer
- MEMPHYS-Center for Biomembrane Physics, University of Southern Denmark, Odense, Denmark
| | - Luis A. Bagatolli
- MEMPHYS-Center for Biomembrane Physics, University of Southern Denmark, Odense, Denmark
| | - Lars M. Rasmussen
- Department of Clinical Biochemistry and Pharmacology, Odense University Hospital, Odense, Denmark; and
| | - Akhmadjon Irmukhamedov
- Department of Cardiac, Thoracic and Vascular Surgery, Odense University Hospital, Odense, Denmark
| | - Koen D. Reesink
- Department of Biomedical Engineering, Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, The Netherlands
| | - Jo G. R. De Mey
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, Odense, Denmark
- Department of Cardiac, Thoracic and Vascular Surgery, Odense University Hospital, Odense, Denmark
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18
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The systolic–diastolic difference in carotid stiffness is increased in type 2 diabetes. J Hypertens 2017; 35:1052-1060. [DOI: 10.1097/hjh.0000000000001298] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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19
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Bruno RM, Reesink KD, Ghiadoni L. Advances in the non-invasive assessment of vascular dysfunction in metabolic syndrome and diabetes: Focus on endothelium, carotid mechanics and renal vessels. Nutr Metab Cardiovasc Dis 2017; 27:121-128. [PMID: 27773467 DOI: 10.1016/j.numecd.2016.09.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 06/28/2016] [Accepted: 09/04/2016] [Indexed: 12/29/2022]
Abstract
AIM The present paper is a selective review on the methodology and clinical significance of techniques to assess specifically endothelial function, carotid mechanics and renal vascular function, particularly in the light of vascular dysfunction in metabolic syndrome and type 2 diabetes. DATA SYNTHESIS Endothelial dysfunction appears to be earlier detectable in the microcirculation of patients with altered glucose metabolism, while it attains significance in the macrocirculation at more advanced disease stages. Smooth muscle cell dysfunction is now increasingly recognized to play a role both in the development of endothelial dysfunction and abnormal arterial distensibility. Furthermore, impaired glucose metabolism affects carotid mechanics through medial calcification, structural changes in extracellular matrix due to advanced glycation and modification of the collagen/elastin material stiffness. The assessment of renal vascular function by dynamic ultrasound or magnetic resonance imaging has recently emerged as an appealing target for identifying subtle vascular alterations responsible for the development of diabetic nephropathy. CONCLUSIONS Vascular dysfunction represents a major mechanism for the development of cardiovascular disease in patients with abnormal glucose metabolism. Hence, the currently available non-invasive techniques to assess early structural and vascular abnormalities merit recommendation in this population, although their predictive value and sensitivity to monitor treatment-induced changes have not yet been established and are still under investigation.
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Affiliation(s)
- R M Bruno
- Department of Clinical and Experimental Medicine, University of Pisa, Italy
| | - K D Reesink
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, Netherlands; Department of Biomedical Engineering, Cardiovascular Center, Maastricht University Medical Center, Netherlands
| | - L Ghiadoni
- Department of Clinical and Experimental Medicine, University of Pisa, Italy.
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20
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Spronck B. Stiff vessels approached in a flexible way: Advancing quantification and interpretation of arterial stiffness☆. Artery Res 2017. [DOI: 10.1016/j.artres.2017.11.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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21
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Head orientation should be considered in ultrasound studies on carotid artery distensibility. J Hypertens 2016; 34:1551-5. [DOI: 10.1097/hjh.0000000000000985] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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22
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Tan I, Spronck B, Kiat H, Barin E, Reesink KD, Delhaas T, Avolio AP, Butlin M. Heart Rate Dependency of Large Artery Stiffness. Hypertension 2016; 68:236-42. [DOI: 10.1161/hypertensionaha.116.07462] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 04/28/2016] [Indexed: 11/16/2022]
Affiliation(s)
- Isabella Tan
- From the Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia (I.T., B.S., H.K., E.B., A.P.A., M.B.); Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, The Netherlands (B.S., K.D.R., T.D.); and Cardiac Health Institute (H.K.) and Macquarie Heart (E.B.), Macquarie University Hospital, Sydney, NSW, Australia
| | - Bart Spronck
- From the Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia (I.T., B.S., H.K., E.B., A.P.A., M.B.); Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, The Netherlands (B.S., K.D.R., T.D.); and Cardiac Health Institute (H.K.) and Macquarie Heart (E.B.), Macquarie University Hospital, Sydney, NSW, Australia
| | - Hosen Kiat
- From the Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia (I.T., B.S., H.K., E.B., A.P.A., M.B.); Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, The Netherlands (B.S., K.D.R., T.D.); and Cardiac Health Institute (H.K.) and Macquarie Heart (E.B.), Macquarie University Hospital, Sydney, NSW, Australia
| | - Edward Barin
- From the Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia (I.T., B.S., H.K., E.B., A.P.A., M.B.); Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, The Netherlands (B.S., K.D.R., T.D.); and Cardiac Health Institute (H.K.) and Macquarie Heart (E.B.), Macquarie University Hospital, Sydney, NSW, Australia
| | - Koen D. Reesink
- From the Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia (I.T., B.S., H.K., E.B., A.P.A., M.B.); Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, The Netherlands (B.S., K.D.R., T.D.); and Cardiac Health Institute (H.K.) and Macquarie Heart (E.B.), Macquarie University Hospital, Sydney, NSW, Australia
| | - Tammo Delhaas
- From the Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia (I.T., B.S., H.K., E.B., A.P.A., M.B.); Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, The Netherlands (B.S., K.D.R., T.D.); and Cardiac Health Institute (H.K.) and Macquarie Heart (E.B.), Macquarie University Hospital, Sydney, NSW, Australia
| | - Alberto P. Avolio
- From the Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia (I.T., B.S., H.K., E.B., A.P.A., M.B.); Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, The Netherlands (B.S., K.D.R., T.D.); and Cardiac Health Institute (H.K.) and Macquarie Heart (E.B.), Macquarie University Hospital, Sydney, NSW, Australia
| | - Mark Butlin
- From the Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia (I.T., B.S., H.K., E.B., A.P.A., M.B.); Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, Maastricht, The Netherlands (B.S., K.D.R., T.D.); and Cardiac Health Institute (H.K.) and Macquarie Heart (E.B.), Macquarie University Hospital, Sydney, NSW, Australia
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23
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Kataoka Y, Kamijo YI, Ogawa Y, Sumiyoshi E, Nakae M, Ikegawa S, Manabe K, Morikawa M, Nagata M, Takasugi S, Masuki S, Nose H. Effects of hypervolemia by protein and glucose supplementation during aerobic training on thermal and arterial pressure regulations in hypertensive older men. J Appl Physiol (1985) 2016; 121:1021-1031. [PMID: 27197855 DOI: 10.1152/japplphysiol.00033.2016] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 05/18/2016] [Indexed: 11/22/2022] Open
Abstract
In Japan, the incidence of heat illness in older people has rapidly increased during midsummer in the last decade, and we suggested that whey-protein+carbohydrate supplementation during aerobic training would increased plasma volume (PV) to enhance thermoregulatory adaptation in older men (J Appl Physiol 107: 725-733, 2009); however, >60% of people age 65 and older suffer from hypertension, and the symptoms may be worsened by hypervolemia. To examine this, we randomly divided 21 older men (∼69 yr) with ∼160 mmHg for systolic and ∼90 mmHg for diastolic blood pressure at rest into two groups: Glc (n = 11) consuming glucose alone (25 g) and Pro-Glc (n = 10) consuming whey protein (10 g) + glucose (15 g), immediately after cycling exercise at 60-75% of peak aerobic capacity (V̇o2 peak) for 60 min/day, 3 days/wk, for 8 wk. Before and after training, we measured PV (dye dilution), baroreflex sensitivity (BRS) of heart rate (Valsalva maneuver), and carotid arterial compliance (CAC) from carotid arterial diameter (ultrasound imaging) responses to pulsatile arterial pressure change (photoplethysmography) at rest. Additionally, we measured esophageal temperature (Tes) and forearm skin blood flow (plethysmography) during exercise at 60% pretraining V̇o2 peak for 20 min in a warm environment. We found that the forearm skin vascular conductance response to increased Tes was enhanced in Pro-Glc with increased PV, but this was not found in Glc; however, despite the increased PV, arterial blood pressures rather decreased with increased CAC and BRS in Pro-Glc. Thus, the prescription was applicable to older men with hypertension to prevent heat illness during exercise.
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Affiliation(s)
- Yufuko Kataoka
- Department of Sports Medical Sciences, Shinshu University Graduate School of Medicine, Matsumoto Japan
| | - Yoshi-Ichiro Kamijo
- Department of Sports Medical Sciences, Shinshu University Graduate School of Medicine, Matsumoto Japan.,Institute for Biomedical Sciences, Shinshu University, Matsumoto Japan
| | - Yu Ogawa
- Department of Sports Medical Sciences, Shinshu University Graduate School of Medicine, Matsumoto Japan
| | - Eri Sumiyoshi
- Department of Sports Medical Sciences, Shinshu University Graduate School of Medicine, Matsumoto Japan
| | - Mari Nakae
- Department of Sports Medical Sciences, Shinshu University Graduate School of Medicine, Matsumoto Japan
| | - Shigeki Ikegawa
- Department of Sports Medical Sciences, Shinshu University Graduate School of Medicine, Matsumoto Japan
| | - Kazumasa Manabe
- Department of Sports Medical Sciences, Shinshu University Graduate School of Medicine, Matsumoto Japan
| | - Mayuko Morikawa
- Department of Sports Medical Sciences, Shinshu University Graduate School of Medicine, Matsumoto Japan.,Institute for Biomedical Sciences, Shinshu University, Matsumoto Japan.,Jukunentaiikudaigaku Research Center, Matsumoto Japan; and
| | - Masashi Nagata
- Food Science Research Laboratories, Meiji Company, Odawara, Japan
| | - Satoshi Takasugi
- Food Science Research Laboratories, Meiji Company, Odawara, Japan
| | - Shizue Masuki
- Department of Sports Medical Sciences, Shinshu University Graduate School of Medicine, Matsumoto Japan.,Institute for Biomedical Sciences, Shinshu University, Matsumoto Japan
| | - Hiroshi Nose
- Department of Sports Medical Sciences, Shinshu University Graduate School of Medicine, Matsumoto Japan; .,Institute for Biomedical Sciences, Shinshu University, Matsumoto Japan
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24
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Spronck B, Megens RTA, Reesink KD, Delhaas T. A method for three-dimensional quantification of vascular smooth muscle orientation: application in viable murine carotid arteries. Biomech Model Mechanobiol 2015; 15:419-32. [PMID: 26174758 PMCID: PMC4792346 DOI: 10.1007/s10237-015-0699-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 06/26/2015] [Indexed: 12/30/2022]
Abstract
When studying in vivo arterial mechanical behaviour using constitutive models, smooth muscle cells (SMCs) should be considered, while they play an important role in regulating arterial vessel tone. Current constitutive models assume a strictly circumferential SMC orientation, without any dispersion. We hypothesised that SMC orientation would show considerable dispersion in three dimensions and that helical dispersion would be greater than transversal dispersion. To test these hypotheses, we developed a method to quantify the 3D orientation of arterial SMCs. Fluorescently labelled SMC nuclei of left and right carotid arteries of ten mice were imaged using two-photon laser scanning microscopy. Arteries were imaged at a range of luminal pressures. 3D image processing was used to identify individual nuclei and their orientations. SMCs showed to be arranged in two distinct layers. Orientations were quantified by fitting a Bingham distribution to the observed orientations. As hypothesised, orientation dispersion was much larger helically than transversally. With increasing luminal pressure, transversal dispersion decreased significantly, whereas helical dispersion remained unaltered. Additionally, SMC orientations showed a statistically significant (\documentclass[12pt]{minimal}
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\begin{document}$$p < 0.05$$\end{document}p<0.05) mean right-handed helix angle in both left and right arteries and in both layers, which is a relevant finding from a developmental biology perspective. In conclusion, vascular SMC orientation (1) can be quantified in 3D; (2) shows considerable dispersion, predominantly in the helical direction; and (3) has a distinct right-handed helical component in both left and right carotid arteries. The obtained quantitative distribution data are instrumental for constitutive modelling of the artery wall and illustrate the merit of our method.
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Affiliation(s)
- Bart Spronck
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, Universiteitssingel 50, Room 3.359, 6229 ER, Maastricht, The Netherlands.
| | - Remco T A Megens
- Institute for Cardiovascular Prevention, Ludwig-Maximilians-Universität, Pettenkoferstraße 9, 80336, Munich, Germany
| | - Koen D Reesink
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, Universiteitssingel 50, Room 3.359, 6229 ER, Maastricht, The Netherlands
| | - Tammo Delhaas
- Department of Biomedical Engineering, CARIM School for Cardiovascular Diseases, Maastricht University, Universiteitssingel 50, Room 3.359, 6229 ER, Maastricht, The Netherlands
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