1
|
Meskin M, Starkey PA, Kaspersen AE, Ringgaard S, Sand SG, Nygaard JV, Jensen JA, Traberg MS, Johansen P. Investigating the importance of left atrial compliance on fluid dynamics in a novel mock circulatory loop. Sci Rep 2024; 14:1864. [PMID: 38253772 PMCID: PMC10803730 DOI: 10.1038/s41598-024-52327-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Accepted: 01/17/2024] [Indexed: 01/24/2024] Open
Abstract
The left atrium (LA) hemodynamic indices hold prognostic value in various cardiac diseases and disorders. To understand the mechanisms of these conditions and to assess the performance of cardiac devices and interventions, in vitro models can be used to replicate the complex physiological interplay between the pulmonary veins, LA, and left ventricle. In this study, a comprehensive and adaptable in vitro model was created. The model includes a flexible LA made from silicone and allows distinct control over the systolic and diastolic functions of both the LA and left ventricle. The LA was mechanically matched with porcine LAs through expansion tests. Fluid dynamic measures were validated against the literature and pulmonary venous flows recorded on five healthy individuals using magnetic resonance flow imaging. Furthermore, the fluid dynamic measures were also used to construct LA pressure-volume loops. The in vitro pressure and flow recordings expressed a high resemblance to physiological waveforms. By decreasing the compliance of the LA, the model behaved realistically, elevating the a- and v-wave peaks of the LA pressure from 12 to 19 mmHg and 22 to 26 mmHg, respectively, while reducing the S/D ratio of the pulmonary venous flowrate from 1.5 to 0.3. This model provides a realistic platform and framework for developing and evaluating left heart procedures and interventions.
Collapse
Affiliation(s)
- Masoud Meskin
- Cardiovascular Biomechanics Group, Department of Health Technology, Technical University of Denmark, Kgs. Lyngby, Denmark
- Cardiovascular Experimental Laboratory, Department of Electrical and Computer Engineering, Aarhus University, Finlandsgade 22, 8200, Aarhus N, Denmark
| | - Philip Alexander Starkey
- Cardiovascular Experimental Laboratory, Department of Electrical and Computer Engineering, Aarhus University, Finlandsgade 22, 8200, Aarhus N, Denmark
| | | | | | - Signe Gram Sand
- Cardiovascular Experimental Laboratory, Department of Electrical and Computer Engineering, Aarhus University, Finlandsgade 22, 8200, Aarhus N, Denmark
| | - Jens Vinge Nygaard
- Biomechanics and Mechanobiology, Department of Biological and Chemical Engineering, Aarhus University, Aarhus, Denmark
| | - Jørgen Arendt Jensen
- Center for Fast Ultrasound Imaging, Department of Health Technology, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Marie Sand Traberg
- Cardiovascular Biomechanics Group, Department of Health Technology, Technical University of Denmark, Kgs. Lyngby, Denmark
- Center for Fast Ultrasound Imaging, Department of Health Technology, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Peter Johansen
- Cardiovascular Experimental Laboratory, Department of Electrical and Computer Engineering, Aarhus University, Finlandsgade 22, 8200, Aarhus N, Denmark.
| |
Collapse
|
2
|
Spartera M, Stracquadanio A, Pessoa-Amorim G, Harston G, Mazzucco S, Young V, Von Ende A, Hess AT, Ferreira VM, Kennedy J, Neubauer S, Casadei B, Wijesurendra RS. Reduced Left Atrial Rotational Flow Is Independently Associated With Embolic Brain Infarcts. JACC Cardiovasc Imaging 2023; 16:1149-1159. [PMID: 37204381 DOI: 10.1016/j.jcmg.2023.03.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 02/22/2023] [Accepted: 03/10/2023] [Indexed: 05/20/2023]
Abstract
BACKGROUND Up to 25% of embolic strokes occur in individuals without atrial fibrillation (AF) or other identifiable mechanisms. OBJECTIVES This study aims to assess whether left atrial (LA) blood flow characteristics are associated with embolic brain infarcts, independently of AF. METHODS The authors recruited 134 patients: 44 with a history of ischemic stroke and 90 with no history of stroke but CHA2DS2VASc score ≥1. Cardiac magnetic resonance (CMR) evaluated cardiac function and LA 4-dimensional flow parameters, including velocity and vorticity (a measure of rotational flow), and brain magnetic resonance imaging (MRI) was performed to detect large noncortical or cortical infarcts (LNCCIs) (likely embolic), or nonembolic lacunar infarcts. RESULTS Patients (41% female; age 70 ± 9 years) had moderate stroke risk (median CHA2DS2VASc = 3, Q1-Q3: 2-4). Sixty-eight (51%) had diagnosed AF, of whom 58 (43%) were in AF during CMR. Thirty-nine (29%) had ≥1 LNCCI, 20 (15%) had ≥1 lacunar infarct without LNCCI, and 75 (56%) had no infarct. Lower LA vorticity was significantly associated with prevalent LNCCIs after adjustment for AF during CMR, history of AF, CHA2DS2VASc score, LA emptying fraction, LA indexed maximum volume, left ventricular ejection fraction, and indexed left ventricular mass (OR: 2.06 [95% CI: 1.08-3.92 per SD]; P = 0.027). By contrast, LA flow peak velocity was not significantly associated with LNCCIs (P = 0.21). No LA parameter was associated with lacunar infarcts (all P > 0.05). CONCLUSIONS Reduced LA flow vorticity is significantly and independently associated with embolic brain infarcts. Imaging LA flow characteristics may aid identification of individuals who would benefit from anticoagulation for embolic stroke prevention, regardless of heart rhythm.
Collapse
Affiliation(s)
- Marco Spartera
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom; University of Oxford Centre for Clinical Magnetic Resonance Research, Oxford, United Kingdom; Oxford University Hospital NHS Foundation Trust, Oxford, United Kingdom.
| | - Antonio Stracquadanio
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom; University of Oxford Centre for Clinical Magnetic Resonance Research, Oxford, United Kingdom; Oxford University Hospital NHS Foundation Trust, Oxford, United Kingdom
| | - Guilherme Pessoa-Amorim
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom; University of Oxford Centre for Clinical Magnetic Resonance Research, Oxford, United Kingdom; Oxford University Hospital NHS Foundation Trust, Oxford, United Kingdom; CTSU Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom
| | - George Harston
- Oxford University Hospital NHS Foundation Trust, Oxford, United Kingdom
| | - Sara Mazzucco
- Oxford University Hospital NHS Foundation Trust, Oxford, United Kingdom; Wolfson Centre for Prevention of Stroke and Dementia, Nuffield Department of Clinical Neuroscience, Oxford, United Kingdom
| | - Victoria Young
- Oxford University Hospital NHS Foundation Trust, Oxford, United Kingdom
| | - Adam Von Ende
- CTSU Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom
| | - Aaron T Hess
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom; University of Oxford Centre for Clinical Magnetic Resonance Research, Oxford, United Kingdom
| | - Vanessa M Ferreira
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom; University of Oxford Centre for Clinical Magnetic Resonance Research, Oxford, United Kingdom; Oxford University Hospital NHS Foundation Trust, Oxford, United Kingdom
| | - James Kennedy
- Oxford University Hospital NHS Foundation Trust, Oxford, United Kingdom
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom; University of Oxford Centre for Clinical Magnetic Resonance Research, Oxford, United Kingdom; Oxford University Hospital NHS Foundation Trust, Oxford, United Kingdom
| | - Barbara Casadei
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom; Oxford University Hospital NHS Foundation Trust, Oxford, United Kingdom
| | - Rohan S Wijesurendra
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom; University of Oxford Centre for Clinical Magnetic Resonance Research, Oxford, United Kingdom; Oxford University Hospital NHS Foundation Trust, Oxford, United Kingdom; CTSU Nuffield Department of Population Health, University of Oxford, Oxford, United Kingdom
| |
Collapse
|
3
|
On non-Kolmogorov turbulence in blood flow and its possible role in mechanobiological stimulation. Sci Rep 2022; 12:13166. [PMID: 35915207 PMCID: PMC9343407 DOI: 10.1038/s41598-022-16079-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 07/04/2022] [Indexed: 01/09/2023] Open
Abstract
The study of turbulence in physiologic blood flow is important due to its strong relevance to endothelial mechanobiology and vascular disease. Recently, Saqr et al. (Sci Rep 10, 15,492, 2020) discovered non-Kolmogorov turbulence in physiologic blood flow in vivo, traced its origins to the Navier–Stokes equation and demonstrated some of its properties using chaos and hydrodynamic-stability theories. The present work extends these findings and investigates some inherent characteristics of non-Kolmogorov turbulence in monoharmonic and multiharmonic pulsatile flow under ideal physiologic conditions. The purpose of this work is to propose a conjecture for the origins for picoNewton forces that are known to regulate endothelial cells’ functions. The new conjecture relates these forces to physiologic momentum-viscous interactions in the near-wall region of the flow. Here, we used high-resolution large eddy simulation (HRLES) to study pulsatile incompressible flow in a straight pipe of \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$$L/D=20$$\end{document}L/D=20. The simulations presented Newtonian and Carreau–Yasuda fluid flows, at \documentclass[12pt]{minimal}
\usepackage{amsmath}
\usepackage{wasysym}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{amsbsy}
\usepackage{mathrsfs}
\usepackage{upgreek}
\setlength{\oddsidemargin}{-69pt}
\begin{document}$$R{e}_{m}\approx 250$$\end{document}Rem≈250, each represented by one, two and three boundary harmonics. Comparison was established based on maintaining constant time-averaged mass flow rate in all simulations. First, we report the effect of primary harmonics on the global power budget using primitive variables in phase space. Second, we describe the non-Kolmogorov turbulence in frequency domain. Third, we investigate the near-wall coherent structures in time and space domains. Finally, we propose a new conjecture for the role of turbulence in endothelial cells’ mechanobiology. The proposed conjecture correlates near-wall turbulence to a force field of picoNewton scale, suggesting possible relevance to endothelial cells mechanobiology.
Collapse
|
4
|
Parker LP, Svensson Marcial A, Brismar TB, Broman LM, Prahl Wittberg L. Impact of Altered Vena Cava Flow Rates on Right Atrium Flow Characteristics. J Appl Physiol (1985) 2022; 132:1167-1178. [PMID: 35271411 PMCID: PMC9054263 DOI: 10.1152/japplphysiol.00649.2021] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The right atrium (RA) combines the superior (SVC) and inferior vena cava (IVC) flows. Treatments like extracorporeal membrane oxygenation (ECMO) and hemodialysis by catheter alter IVC/SVC flows. Here we assess how altered IVC/SVC flow contributions impact RA flow. Four healthy volunteers were imaged with CT, reconstructed and combined into a patient-averaged model. Large Eddy Simulations (LES) were performed for a range of IVC/SVC flow contributions (30-70% each, increments of 5%) and common flow metrics were recorded. Model sensitivity to reconstruction domain extent, constant/pulsatile inlets and hematocrit was also assessed. Consistent with literature, a single vortex occupied the central RA across all flowrates with a smaller counter-rotating vortex, not previously reported, in the auricle. Vena cava flow was highly helical. RA turbulent kinetic energy (TKE) (P=0.027) and time-averaged wall shear stress (WSS) (P<0.001) increased with SVC flow. WSS was lower in the auricle (2 Pa, P<0.001). WSS in the vena cava were equal at IVC/SVC =65/35%. The model was highly sensitive to the reconstruction domain with cropped geometries lacking helicity in the vena cavae, altering RA flow. RA flow was not significantly affected by constant inlets or hematocrit. The rotational flow conventionally described in the RA is confirmed however a new, smaller vortex was also recorded in the auricle. When IVC flow dominates, as is normal, TKE in the RA is reduced and WSS in the vena cavae equalize. Significant helicity exists in the vena cava, a result of distal geometry and this geometry appears crucial to accurately simulating RA flow.
Collapse
Affiliation(s)
- Louis P Parker
- FLOW and BioMEx, Department of Engineering Mechanics, Royal Institute of Technology, KTH, Stockholm, Sweden
| | - Anders Svensson Marcial
- Department of Clinical Science, Intervention and Technology at Karolinska Institute, Division of Medical Imaging and Technology, Stockholm, Sweden.,Department of Radiology, Karolinska University Hospital in Huddinge, Stockholm, Sweden
| | - Torkel B Brismar
- Department of Clinical Science, Intervention and Technology at Karolinska Institute, Division of Medical Imaging and Technology, Stockholm, Sweden.,Department of Radiology, Karolinska University Hospital in Huddinge, Stockholm, Sweden
| | - Lars Mikael Broman
- ECMO Centre Karolinska, Pediatric Perioperative Medicine and Intensive Care, Karolinska University Hospital, Stockholm, Sweden.,Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Lisa Prahl Wittberg
- FLOW and BioMEx, Department of Engineering Mechanics, Royal Institute of Technology, KTH, Stockholm, Sweden
| |
Collapse
|
5
|
OUP accepted manuscript. Eur Heart J Cardiovasc Imaging 2022; 23:970-978. [DOI: 10.1093/ehjci/jeac070] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 03/24/2022] [Indexed: 11/13/2022] Open
|
6
|
Spartera M, Stracquadanio A, Pessoa-Amorim G, Von Ende A, Fletcher A, Manley P, Ferreira VM, Hess AT, Hopewell JC, Neubauer S, Wijesurendra RS, Casadei B. The impact of atrial fibrillation and stroke risk factors on left atrial blood flow characteristics. Eur Heart J Cardiovasc Imaging 2021; 23:115-123. [PMID: 34687541 PMCID: PMC8685601 DOI: 10.1093/ehjci/jeab213] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Accepted: 10/06/2021] [Indexed: 12/03/2022] Open
Abstract
AIMS Altered left atrial (LA) blood flow characteristics account for an increase in cardioembolic stroke risk in atrial fibrillation (AF). Here, we aimed to assess whether exposure to stroke risk factors is sufficient to alter LA blood flow even in the presence of sinus rhythm (SR). METHODS AND RESULTS We investigated 95 individuals: 37 patients with persistent AF, who were studied before and after cardioversion [Group 1; median CHA2DS2-VASc = 2.0 (1.5-3.5)]; 35 individuals with no history of AF but similar stroke risk to Group 1 [Group 2; median CHA2DS2-VASc = 3.0 (2.0-4.0)]; and 23 low-risk individuals in SR [Group 3; median CHA2DS2-VASc = 0.0 (0.0-0.0)]. Cardiac function and LA flow characteristics were evaluated using cardiac magnetic resonance. Before cardioversion, Group 1 displayed impaired left ventricular (LV) and LA function, reduced LA flow velocities and vorticity, and a higher normalized vortex volume (all P < 0.001 vs. Groups 2 and 3). After restoration of SR at ≥4-week post-cardioversion, LV systolic function and LA flow parameters improved significantly (all P < 0.001 vs. pre-cardioversion) and were no longer different from those in Group 2. However, in the presence of SR, LA flow peak and mean velocity, and vorticity were lower in Groups 1 and 2 vs. Group 3 (all P < 0.01), and were associated with impaired LA emptying fraction (LAEF) and LV diastolic dysfunction. CONCLUSION Patients at moderate-to-high stroke risk display altered LA flow characteristics in SR in association with an LA myopathic phenotype and LV diastolic dysfunction, regardless of a history of AF.
Collapse
Affiliation(s)
- Marco Spartera
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Level 6, West Wing, Headley Way, Oxford OX3 9DU, UK
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford, UK
| | - Antonio Stracquadanio
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Level 6, West Wing, Headley Way, Oxford OX3 9DU, UK
| | - Guilherme Pessoa-Amorim
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Level 6, West Wing, Headley Way, Oxford OX3 9DU, UK
| | - Adam Von Ende
- Nuffield Department of Population Health, University of Oxford, Oxford, UK
| | - Alison Fletcher
- Acute Vascular Imaging Centre, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Peter Manley
- Acute Vascular Imaging Centre, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Vanessa M Ferreira
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Level 6, West Wing, Headley Way, Oxford OX3 9DU, UK
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford, UK
| | - Aaron T Hess
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford, UK
| | - Jemma C Hopewell
- Nuffield Department of Population Health, University of Oxford, Oxford, UK
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Level 6, West Wing, Headley Way, Oxford OX3 9DU, UK
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford, UK
| | - Rohan S Wijesurendra
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Level 6, West Wing, Headley Way, Oxford OX3 9DU, UK
- Oxford Centre for Clinical Magnetic Resonance Research, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Oxford, UK
| | - Barbara Casadei
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Level 6, West Wing, Headley Way, Oxford OX3 9DU, UK
| |
Collapse
|
7
|
Spartera M, Pessoa-Amorim G, Stracquadanio A, Von Ende A, Fletcher A, Manley P, Neubauer S, Ferreira VM, Casadei B, Hess AT, Wijesurendra RS. Left atrial 4D flow cardiovascular magnetic resonance: a reproducibility study in sinus rhythm and atrial fibrillation. J Cardiovasc Magn Reson 2021; 23:29. [PMID: 33745457 PMCID: PMC7983287 DOI: 10.1186/s12968-021-00729-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 02/03/2021] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND Four-dimensional (4D) flow cardiovascular magnetic resonance (CMR) allows sophisticated quantification of left atrial (LA) blood flow, and could yield novel biomarkers of propensity for intra-cardiac thrombus formation and embolic stroke. As reproducibility is critically important to diagnostic performance, we systematically investigated technical and temporal variation of LA 4D flow in atrial fibrillation (AF) and sinus rhythm (SR). METHODS Eighty-six subjects (SR, n = 64; AF, n = 22) with wide-ranging stroke risk (CHA2DS2VASc 0-6) underwent LA 4D flow assessment of peak and mean velocity, vorticity, vortex volume, and stasis. Eighty-five (99%) underwent a second acquisition within the same session, and 74 (86%) also returned at 30 (27-35) days for an interval scan. We assessed variability attributable to manual contouring (intra- and inter-observer), and subject repositioning and reacquisition of data, both within the same session (same-day scan-rescan), and over time (interval scan). Within-subject coefficients of variation (CV) and bootstrapped 95% CIs were calculated and compared. RESULTS Same-day scan-rescan CVs were 6% for peak velocity, 5% for mean velocity, 7% for vorticity, 9% for vortex volume, and 10% for stasis, and were similar between SR and AF subjects (all p > 0.05). Interval-scan variability was similar to same-day scan-rescan variability for peak velocity, vorticity, and vortex volume (all p > 0.05), and higher for stasis and mean velocity (interval scan CVs of 14% and 8%, respectively, both p < 0.05). Longitudinal changes in heart rate and blood pressure at the interval scan in the same subjects were associated with significantly higher variability for LA stasis (p = 0.024), but not for the remaining flow parameters (all p > 0.05). SR subjects showed significantly greater interval-scan variability than AF patients for mean velocity, vortex volume, and stasis (all p < 0.05), but not peak velocity or vorticity (both p > 0.05). CONCLUSIONS LA peak velocity and vorticity are the most reproducible and temporally stable novel LA 4D flow biomarkers, and are robust to changes in heart rate, blood pressure, and differences in heart rhythm.
Collapse
Affiliation(s)
- Marco Spartera
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, West Wing, Headley Way, Oxford, UK.
- The University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Oxford, UK.
| | - Guilherme Pessoa-Amorim
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, West Wing, Headley Way, Oxford, UK
- The University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Oxford, UK
| | - Antonio Stracquadanio
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, West Wing, Headley Way, Oxford, UK
- The University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Oxford, UK
| | - Adam Von Ende
- Department of Population Health, CTSU Nuffield University of Oxford, Oxford, UK
| | - Alison Fletcher
- The University of Oxford Acute Vascular Imaging Centre (AVIC), Oxford, UK
| | - Peter Manley
- The University of Oxford Acute Vascular Imaging Centre (AVIC), Oxford, UK
| | - Stefan Neubauer
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, West Wing, Headley Way, Oxford, UK
- The University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Oxford, UK
| | - Vanessa M Ferreira
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, West Wing, Headley Way, Oxford, UK
- The University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Oxford, UK
| | - Barbara Casadei
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, West Wing, Headley Way, Oxford, UK
| | - Aaron T Hess
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, West Wing, Headley Way, Oxford, UK
- The University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Oxford, UK
| | - Rohan S Wijesurendra
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, John Radcliffe Hospital, University of Oxford, West Wing, Headley Way, Oxford, UK
- The University of Oxford Centre for Clinical Magnetic Resonance Research (OCMR), Oxford, UK
| |
Collapse
|
8
|
de Oliveira DC, Owen DG, Qian S, Green NC, Espino DM, Shepherd DET. Computational fluid dynamics of the right atrium: Assessment of modelling criteria for the evaluation of dialysis catheters. PLoS One 2021; 16:e0247438. [PMID: 33630903 PMCID: PMC7906423 DOI: 10.1371/journal.pone.0247438] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 02/06/2021] [Indexed: 11/19/2022] Open
Abstract
Central venous catheters are widely used in haemodialysis therapy, having to respect design requirements for appropriate performance. These are placed within the right atrium (RA); however, there is no prior computational study assessing different catheter designs while mimicking their native environment. Here, a computational fluid dynamics model of the RA, based on realistic geometry and transient physiological boundary conditions, was developed and validated. Symmetric, split and step catheter designs were virtually placed in the RA and their performance was evaluated by: assessing their interaction with the RA haemodynamic environment through prediction of flow vorticity and wall shear stress (WSS) magnitudes (1); and quantifying recirculation and tip shear stress (2). Haemodynamic predictions from our RA model showed good agreement with the literature. Catheter placement in the RA increased average vorticity, which could indicate alterations of normal blood flow, and altered WSS magnitudes and distribution, which could indicate changes in tissue mechanical properties. All designs had recirculation and elevated shear stress values, which can induce platelet activation and subsequently thrombosis. The symmetric design, however, had the lowest associated values (best performance), while step design catheters working in reverse mode were associated with worsened performance. Different tip placements also impacted on catheter performance. Our findings suggest that using a realistically anatomical RA model to study catheter performance and interaction with the haemodynamic environment is crucial, and that care needs to be given to correct tip placement within the RA for improved recirculation percentages and diminished shear stress values.
Collapse
Affiliation(s)
- Diana C. de Oliveira
- Department of Mechanical Engineering, University of Birmingham, Birmingham, United Kingdom
| | - David G. Owen
- Department of Mechanical Engineering, University of Birmingham, Birmingham, United Kingdom
| | - Shuang Qian
- Department of Mechanical Engineering, University of Birmingham, Birmingham, United Kingdom
| | - Naomi C. Green
- Department of Mechanical Engineering, University of Birmingham, Birmingham, United Kingdom
| | - Daniel M. Espino
- Department of Mechanical Engineering, University of Birmingham, Birmingham, United Kingdom
| | - Duncan E. T. Shepherd
- Department of Mechanical Engineering, University of Birmingham, Birmingham, United Kingdom
| |
Collapse
|
9
|
Miyagi Y, Kawase Y, Kunugi S, Oomori H, Sasaki T, Sakamoto SI, Ishii Y, Morota T, Nitta T, Shimizu A. Histological properties of oscillating intracardiac masses associated with cardiac implantable electric devices. J Arrhythm 2020; 36:478-484. [PMID: 32528575 PMCID: PMC7279976 DOI: 10.1002/joa3.12346] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 03/17/2020] [Accepted: 03/30/2020] [Indexed: 11/15/2022] Open
Abstract
Background There have been a few cases of echogenic cardiac implantable electric device (CIED) lead‐associated oscillating intracardiac masses (ICMs) in leads imaged by echocardiography. The histological properties of ICMs could help clarify the etiological diagnosis. Although there is extensive literature on mass size, the histological properties of such masses have not been characterized. The aim of this research was to clarify the histological features of oscillating ICMs in CIED patients. Methods Preoperative echocardiography was performed in all candidates for CIED removal. In the patients with ICMs, specimens were obtained by 3 methods: direct tissue collection during open‐heart surgery; tissue collection together with the CIED lead during transvenous extraction; and tissue collection by catheter vacuum during transvenous CIED removal. A standard histopathological examination of ICM tissue was performed. Results A total of 106 patients underwent lead removal in our institute (April 2009‐March 2018); 14 patients had an ICM (13.2%), and 7 specimens were obtained in patients with CIED lead‐related ICM. Following histological examination, 2 types of ICM were identified: one mainly composed of thickened endocardium (EN type; 3 patients), and the other mainly an aggregate of inflammatory cells as a neutrophil cell (NC type; 4 patients). Conclusions Two histological types of intracardiac masses, including a thickened endocardium type and a neutrophil cell type, were identified. These classifications might help make an accurate histological diagnosis of lead‐associated intracardiac masses.
Collapse
Affiliation(s)
- Yasuo Miyagi
- Department of Cardiovascular Surgery Nippon Medical School Tokyo Japan
| | - Yasuhiro Kawase
- Department of Cardiovascular Surgery Nippon Medical School Tokyo Japan
| | - Shinobu Kunugi
- Department of Analytic Human Pathology Nippon Medical School Tokyo Japan
| | - Hiroya Oomori
- Department of Cardiovascular Surgery Nippon Medical School Tokyo Japan
| | - Takashi Sasaki
- Department of Cardiovascular Surgery Nippon Medical School Tokyo Japan
| | | | - Yosuke Ishii
- Department of Cardiovascular Surgery Nippon Medical School Tokyo Japan
| | - Tetsuro Morota
- Department of Cardiovascular Surgery Nippon Medical School Tokyo Japan
| | - Takashi Nitta
- Department of Cardiovascular Surgery Nippon Medical School Tokyo Japan
| | - Akira Shimizu
- Department of Analytic Human Pathology Nippon Medical School Tokyo Japan
| |
Collapse
|
10
|
Dewhurst P, Coats L, Parikh JD, Hollingsworth KG, Gan L. The role of flow rotation in the adult right atrium: a 4D flow cardiovascular magnetic resonance study. Physiol Meas 2020; 41:035007. [DOI: 10.1088/1361-6579/ab7d77] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
11
|
Assessment of the Flow Field in the HeartMate 3 Using Three-Dimensional Particle Tracking Velocimetry and Comparison to Computational Fluid Dynamics. ASAIO J 2020; 66:173-182. [DOI: 10.1097/mat.0000000000000987] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
|
12
|
Gülan U, Appa H, Corso P, Templin C, Bezuidenhout D, Zilla P, Duru F, Holzner M. Performance analysis of the transcatheter aortic valve implantation on blood flow hemodynamics: An optical imaging‐based in vitro study. Artif Organs 2019; 43:E282-E293. [DOI: 10.1111/aor.13504] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 04/11/2019] [Accepted: 05/23/2019] [Indexed: 11/29/2022]
Affiliation(s)
- Utku Gülan
- Institute for Environmental Engineering Swiss Federal Institute of Technology Zurich Zurich Switzerland
| | - Harish Appa
- Strait Access Technologies University of Cape Town Observatory South Africa
| | - Pascal Corso
- Institute for Environmental Engineering Swiss Federal Institute of Technology Zurich Zurich Switzerland
| | | | - Deon Bezuidenhout
- Strait Access Technologies University of Cape Town Observatory South Africa
- Cardiovascular Research Unit University of Cape Town Observatory South Africa
| | - Peter Zilla
- Strait Access Technologies University of Cape Town Observatory South Africa
- Cardiovascular Research Unit University of Cape Town Observatory South Africa
| | - Firat Duru
- Department of Cardiology University Heart Center Zurich Switzerland
- Center for Integrative Human Physiology University of Zurich Zurich Switzerland
| | - Markus Holzner
- Institute for Environmental Engineering Swiss Federal Institute of Technology Zurich Zurich Switzerland
| |
Collapse
|
13
|
A Novel Approach for 3D-Structural Identification through Video Recording: Magnified Tracking. SENSORS 2019; 19:s19051229. [PMID: 30862051 PMCID: PMC6427300 DOI: 10.3390/s19051229] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 03/05/2019] [Accepted: 03/05/2019] [Indexed: 11/23/2022]
Abstract
Advancements in optical imaging devices and computer vision algorithms allow the exploration of novel diagnostic techniques for use within engineering systems. A recent field of application lies in the adoption of such devices for non-contact vibrational response recordings of structures, allowing high spatial density measurements without the burden of heavy cabling associated with conventional technologies. This, however, is not a straightforward task due to the typically low-amplitude displacement response of structures under ambient operational conditions. A novel framework, namely Magnified Tracking (MT), is proposed herein to overcome this limitation through the synergistic use of two computer vision techniques. The recently proposed phase-based motion magnification (PBMM) framework, for amplifying motion in a video within a defined frequency band, is coupled with motion tracking by means of particle tracking velocimetry (PTV). An experimental campaign was conducted to validate a proof-of-concept, where the dynamic response of a shear frame was measured both by conventional sensors as well as a video camera setup, and cross-compared to prove the feasibility of the proposed non-contact approach. The methodology was explored both in 2D and 3D configurations, with PTV revealing a powerful tool for the measurement of perceptible motion. When MT is utilized for tracking “imperceptible” structural responses (i.e., below PTV sensitivity), via the use of PBMM around the resonant frequencies of the structure, the amplified motion reveals the operational deflection shapes, which are otherwise intractable. The modal results extracted from the magnified videos, using PTV, demonstrate MT to be a viable non-contact alternative for 3D modal identification with the benefit of a spatially dense measurement grid.
Collapse
|
14
|
Gülan U, Saguner AM, Akdis D, Gotschy A, Tanner FC, Kozerke S, Manka R, Brunckhorst C, Holzner M, Duru F. Hemodynamic Changes in the Right Ventricle Induced by Variations of Cardiac Output: A Possible Mechanism for Arrhythmia Occurrence in the Outflow Tract. Sci Rep 2019; 9:100. [PMID: 30643204 PMCID: PMC6331649 DOI: 10.1038/s41598-018-36614-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 11/23/2018] [Indexed: 01/07/2023] Open
Abstract
The rationale of this paper is to investigate right ventricular (RV) hemodynamics in relation to changes in cardiac output, and in particular to study exercise-induced stresses at the RV outflow tract (RVOT), which is a common site of ventricular arrhythmias in the athlete’s heart. We hypothesize that the thin-walled RVOT is exposed to high wall shear stresses (WSS) during physiological states associated with high cardiac output such as exercise, and therefore, may be particularly prone to substrate formation leading to ventricular tachyarrhythmias. 3D Particle Tracking Velocimetry (3D-PTV), an optical imaging method, has been performed in a novel anatomically accurate compliant silicone right heart model derived from a high resolution MRI heart scan of a healthy male proband. RV and RVOT flow patterns at resting conditions were obtained from two healthy athletic male proband’s hearts and two patients with arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) via phase contrast magnetic resonance imaging (PC-MRI). The healthy case was used as a reference for validating the in vitro flow patterns of the silicone model, while the diseased cases were used to generalize our findings and investigate possible changes in hemodynamic stresses with RV morphological remodelling. Our results showed that both healthy and diseased geometries consistently displayed an increased WSS in the RVOT relative to the rest of the RV. We found that increases in cardiac output may lead to increases of mean kinetic energy (MKE), laminar viscous dissipation and WSS at the RVOT. Furthermore, higher peak WSS magnitudes were found for the diseased cases. The identified high WSS regions may correlate with the common site of RVOT ventricular tachycardia in athletes and patients with ARVC/D. Our results imply that exercise, as well as anatomical and functional remodeling might alter RV wall shear stress both in magnitude and spatial distribution, leading to increased hemodynamic stresses in the RVOT.
Collapse
Affiliation(s)
- Utku Gülan
- ETH Zurich, Institute of Environmental Engineering, Zurich, 8093, Switzerland.
| | | | - Deniz Akdis
- University Heart Center, Department of Cardiology, Zurich, 8091, Switzerland
| | - Alexander Gotschy
- University Heart Center, Department of Cardiology, Zurich, 8091, Switzerland.,Institute for Biomedical Engineering, University and ETH Zurich, Zurich, 8092, Switzerland
| | - Felix C Tanner
- University Heart Center, Department of Cardiology, Zurich, 8091, Switzerland
| | - Sebastian Kozerke
- Institute for Biomedical Engineering, University and ETH Zurich, Zurich, 8092, Switzerland
| | - Robert Manka
- University Heart Center, Department of Cardiology, Zurich, 8091, Switzerland.,Institute of Diagnostic and Interventional Radiology, University and ETH Zurich, Zurich, 8092, Switzerland
| | - Corinna Brunckhorst
- University Heart Center, Department of Cardiology, Zurich, 8091, Switzerland
| | - Markus Holzner
- ETH Zurich, Institute of Environmental Engineering, Zurich, 8093, Switzerland
| | - Firat Duru
- University Heart Center, Department of Cardiology, Zurich, 8091, Switzerland.,Center for Integrative Human Physiology, University of Zurich, Zurich, 8091, Switzerland
| |
Collapse
|
15
|
Dillon-Murphy D, Marlevi D, Ruijsink B, Qureshi A, Chubb H, Kerfoot E, O'Neill M, Nordsletten D, Aslanidi O, de Vecchi A. Modeling Left Atrial Flow, Energy, Blood Heating Distribution in Response to Catheter Ablation Therapy. Front Physiol 2019; 9:1757. [PMID: 30618785 PMCID: PMC6302108 DOI: 10.3389/fphys.2018.01757] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 11/20/2018] [Indexed: 11/16/2022] Open
Abstract
Introduction: Atrial fibrillation (AF) is a widespread cardiac arrhythmia that commonly affects the left atrium (LA), causing it to quiver instead of contracting effectively. This behavior is triggered by abnormal electrical impulses at a specific site in the atrial wall. Catheter ablation (CA) treatment consists of isolating this driver site by burning the surrounding tissue to restore sinus rhythm (SR). However, evidence suggests that CA can concur to the formation of blood clots by promoting coagulation near the heat source and in regions with low flow velocity and blood stagnation. Methods: A patient-specific modeling workflow was created and applied to simulate thermal-fluid dynamics in two patients pre- and post-CA. Each model was personalized based on pre- and post-CA imaging datasets. The wall motion and anatomy were derived from SSFP Cine MRI data, while the trans-valvular flow was based on Doppler ultrasound data. The temperature distribution in the blood was modeled using a modified Pennes bioheat equation implemented in a finite-element based Navier-Stokes solver. Blood particles were also classified based on their residence time in the LA using a particle-tracking algorithm. Results: SR simulations showed multiple short-lived vortices with an average blood velocity of 0.2-0.22 m/s. In contrast, AF patients presented a slower vortex and stagnant flow in the LA appendage, with the average blood velocity reduced to 0.08–0.14 m/s. Restoration of SR also increased the blood kinetic energy and the viscous dissipation due to the presence of multiple vortices. Particle tracking showed a dramatic decrease in the percentage of blood remaining in the LA for longer than one cycle after CA (65.9 vs. 43.3% in patient A and 62.2 vs. 54.8% in patient B). Maximum temperatures of 76° and 58°C were observed when CA was performed near the appendage and in a pulmonary vein, respectively. Conclusion: This computational study presents novel models to elucidate relations between catheter temperature, patient-specific atrial anatomy and blood velocity, and predict how they change from SR to AF. The models can quantify blood flow in critical regions, including residence times and temperature distribution for different catheter positions, providing a basis for quantifying stroke risks.
Collapse
Affiliation(s)
- Desmond Dillon-Murphy
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - David Marlevi
- School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Bram Ruijsink
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Ahmed Qureshi
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Henry Chubb
- Department of Cardiothoracic Surgery, Stanford University, Palo Alto, CA, United States
| | - Eric Kerfoot
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Mark O'Neill
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - David Nordsletten
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Oleg Aslanidi
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| | - Adelaide de Vecchi
- School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom
| |
Collapse
|
16
|
The influence of bileaflet prosthetic aortic valve orientation on the blood flow patterns in the ascending aorta. Med Eng Phys 2018; 60:61-69. [DOI: 10.1016/j.medengphy.2018.07.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Revised: 07/23/2018] [Accepted: 07/24/2018] [Indexed: 11/19/2022]
|