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Al-Zubaidi FI, Hussein N, Smith H, Al-Adhami A, Sitaranjan D, Caputo M, Angelini GD, Harky A, Vohra HA. 20 Years of triple-valve surgery in the UK: demographic and outcome trends. Eur J Cardiothorac Surg 2024; 66:ezae268. [PMID: 38984815 PMCID: PMC11246163 DOI: 10.1093/ejcts/ezae268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Revised: 06/26/2024] [Accepted: 07/09/2024] [Indexed: 07/11/2024] Open
Abstract
OBJECTIVES To describe evolving demographic trends and early outcomes in patients undergoing triple-valve surgery in the UK between 2000 and 2019. METHODS We planned a retrospective analysis of national registry data including patients undergoing triple-valve surgery for all aetiologies of disease. We excluded patients in a critical preoperative state and those with missing admission dates. The study cohort was split into 5 consecutive 4-year cohorts (groups A, B, C, D and E). The primary outcome was in-hospital mortality, and secondary outcomes included prolonged admission, re-exploration for bleeding, postoperative stroke and postoperative dialysis. Binary logistic regression models were used to establish independent predictors of mortality, stroke, postoperative dialysis and re-exploration for bleeding in this high-risk cohort. RESULTS We identified 1750 patients undergoing triple-valve surgery in the UK between 2000 and 2019. Triple valve surgery represents 3.1% of all patients in the dataset. Overall mean age of patients was 68.5 ± 12 years, having increased from 63 ±12 years in group A to 69 ± 12 years in group E (P < 0.001). Overall in-hospital mortality rate was 9%, dropping from 21% in group A to 7% in group E (P < 0.001). Overall rates of re-exploration for bleeding (11%, P = 0.308) and postoperative dialysis (11%, P = 0.066) remained high across the observed time period. Triple valve replacement, redo sternotomy and poor preoperative left ventricular ejection fraction emerged as strong independent predictors of mortality. CONCLUSIONS Triple-valve surgery remains rare in the UK. Early postoperative outcomes for triple valve surgery have improved over time. Redo sternotomy is a significant predictor of mortality. Attempts should be made to repair the mitral and/or tricuspid valves where technically possible.
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Affiliation(s)
| | - Nabil Hussein
- Department of Cardiac Surgery, Castle Hill Hospital, Hull, UK
| | - Harry Smith
- Department of Cardiac Surgery, Royal Papworth Hospital, Cambridge, UK
| | - Ahmed Al-Adhami
- Department of Cardiac Surgery, Royal Papworth Hospital, Cambridge, UK
| | - Daniel Sitaranjan
- Department of Cardiac Surgery, Royal Papworth Hospital, Cambridge, UK
| | - Massimo Caputo
- Department of Cardiac Surgery, Bristol Heart Institute, Bristol, UK
| | | | - Amer Harky
- Department of Cardiac Surgery, Liverpool Heart & Chest, Liverpool, UK
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Aurigemma GP, Gentile BA, Dickey JB, Fitzgibbons TP, Tighe DA, Kakouros N, Kovell LC, Gottbrecht MF, Narvaez-Guerra O, Qureshi W, Gerson DS, Parker MW. Insights Into the Standard Echocardiographic Views From Multimodality Imaging: Ventricles, Pericardium, Valves, and Atria. J Am Soc Echocardiogr 2023; 36:1266-1289. [PMID: 37549797 DOI: 10.1016/j.echo.2023.07.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2022] [Revised: 07/19/2023] [Accepted: 07/20/2023] [Indexed: 08/09/2023]
Abstract
The widespread use of cardiac computed tomography and cardiac magnetic resonance imaging in patients undergoing echocardiography presents an opportunity to correlate the images side by side. Accordingly, the aim of this report is to review aspects of the standard echocardiographic examination alongside similarly oriented images from the two tomographic imaging modalities. It is hoped that this exercise will enhance understanding of the structures depicted by echocardiography as they relate to other structures in the thorax. In addition to reviewing basic cardiac anatomy, the authors take advantage of these correlations with computed tomography and cardiac magnetic resonance imaging to better understand the issue of foreshortening, a common pitfall in transthoracic echocardiography. The authors also highlight an important role that three-dimensional echocardiography can potentially play in the future, especially as advances in image processing permit higher fidelity multiplanar reconstruction images.
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Affiliation(s)
- Gerard P Aurigemma
- Division of Cardiovascular Medicine, Department of Medicine, UMass Chan Medical School and UMass Memorial Healthcare, Worcester, Massachusetts.
| | - Bryon A Gentile
- Division of Cardiovascular Medicine, Department of Medicine, UMass Chan Medical School and UMass Memorial Healthcare, Worcester, Massachusetts
| | - John B Dickey
- Division of Cardiovascular Medicine, Department of Medicine, UMass Chan Medical School and UMass Memorial Healthcare, Worcester, Massachusetts
| | - Timothy P Fitzgibbons
- Division of Cardiovascular Medicine, Department of Medicine, UMass Chan Medical School and UMass Memorial Healthcare, Worcester, Massachusetts
| | - Dennis A Tighe
- Division of Cardiovascular Medicine, Department of Medicine, UMass Chan Medical School and UMass Memorial Healthcare, Worcester, Massachusetts
| | - Nikolaos Kakouros
- Division of Cardiovascular Medicine, Department of Medicine, UMass Chan Medical School and UMass Memorial Healthcare, Worcester, Massachusetts
| | - Lara C Kovell
- Division of Cardiovascular Medicine, Department of Medicine, UMass Chan Medical School and UMass Memorial Healthcare, Worcester, Massachusetts
| | - Matthew F Gottbrecht
- Division of Cardiovascular Medicine, Department of Medicine, UMass Chan Medical School and UMass Memorial Healthcare, Worcester, Massachusetts
| | - Offdan Narvaez-Guerra
- Division of Cardiovascular Medicine, Department of Medicine, UMass Chan Medical School and UMass Memorial Healthcare, Worcester, Massachusetts
| | - Waqas Qureshi
- Division of Cardiovascular Medicine, Department of Medicine, UMass Chan Medical School and UMass Memorial Healthcare, Worcester, Massachusetts
| | - David S Gerson
- Department of Radiology, UMass Chan Medical School and UMass Memorial Healthcare, Worcester, Massachusetts
| | - Matthew W Parker
- Division of Cardiovascular Medicine, Department of Medicine, UMass Chan Medical School and UMass Memorial Healthcare, Worcester, Massachusetts
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3
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de Oliveira DC, Espino DM, Deorsola L, Buchan K, Dawson D, Shepherd DET. A geometry-based finite element tool for evaluating mitral valve biomechanics. Med Eng Phys 2023; 121:104067. [PMID: 37985031 DOI: 10.1016/j.medengphy.2023.104067] [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: 03/15/2023] [Revised: 09/08/2023] [Accepted: 10/30/2023] [Indexed: 11/22/2023]
Abstract
Mitral valve function depends on its complex geometry and tissue health, with alterations in shape and tissue response affecting the long-term restorarion of function. Previous computational frameworks for biomechanical assessment are mostly based on patient-specific geometries; however, these are not flexible enough to yield a variety of models and assess mitral closure for individually tuned morphological parameters or material property representations. This study details the finite element approach implemented in our previously developed toolbox to assess mitral valve biomechanics and showcases its flexibility through the generation and biomechanical evaluation of different models. A healthy valve geometry was generated and its computational predictions for biomechanics validated against data in the literature. Moreover, two mitral valve models including geometric alterations associated with disease were generated and analysed. The healthy mitral valve model yielded biomechanical predictions in terms of valve closure dynamics, leaflet stresses and papillary muscle and chordae forces comparable to previous computational and experimental studies. Mitral valve function was compromised in geometries representing disease, expressed by the presence of regurgitating areas, elevated stress on the leaflets and unbalanced subvalvular apparatus forces. This showcases the flexibility of the toolbox concerning the generation of a range of mitral valve models with varying geometric definitions and material properties and the evaluation of their biomechanics.
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Affiliation(s)
- Diana C de Oliveira
- Department of Mechanical Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom; Current affiliation: Department of Mechanical Engineering, University College London, Torrington Place, London WC1E 7JE, United Kingdom.
| | - Daniel M Espino
- Department of Mechanical Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Luca Deorsola
- Paedriatic Cardiac Surgery, Ospedale Infantile Regina Margherita Sant Anna, Turin 10126, Italy
| | - Keith Buchan
- Department of Cardiothoracic Surgery, Aberdeen Royal Infirmary, Aberdeen AB24 2ZN, Scotland, UK
| | - Dana Dawson
- School of Medicine, University of Aberdeen, Aberdeen AB25 2ZD, Scotland, UK; Cardiology Department, Aberdeen Royal Infirmary, Aberdeen AB25 2ZN, Scotland, UK
| | - Duncan E T Shepherd
- Department of Mechanical Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
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4
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Huang L, Lai X, Xu L, Zeng Z, Xia H. Left ventricular reverse remodeling after transcatheter aortic valve replacement for predominant aortic stenosis and mixed aortic valve disease. JOURNAL OF CLINICAL ULTRASOUND : JCU 2023; 51:1453-1460. [PMID: 37877538 DOI: 10.1002/jcu.23585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2023] [Revised: 09/07/2023] [Accepted: 09/28/2023] [Indexed: 10/26/2023]
Abstract
BACKGROUND Mixed aortic valve disease (MAVD) is a frequent concomitant valve disease with unique cardiac pathological changes compared to predominant aortic stenosis (PAS). The previous studies about the MAVD are contradictory. Therefore, a new perspective is needed to assess the value of TAVR for this cohort of patients. METHODS From January 2018 to December 2021, 90 MAVD patients and 72 PAS patients who underwent TAVR in our hospital were collected. 1:1 propensity score matching analysis was used to control the bias in patient selection. The dynamic changes in left ventricular morphology and hemodynamics were compared by generalized estimating equations. Univariate or multivariate logistic regression analysis was used to screen for independent risk factors for the non-occurrence of left ventricular reverse remodeling (non-LVRR). RESULTS After the matching procedure, 112 patients were included in the analysis (56 in each group). Baseline characteristics were similar between the two groups. LVRR occurred in both groups, but MAVD had greater left ventricular end-diastolic volume index and left ventricular mass index, a higher incidence of mitral regurgitation (MR), and a more pronounced transformation of ventricular geometry patterns. Post-operative MR (odd ratio [OR]: 10.05; 95% confidence interval [CI]: 2.08-48.57; p < .001) and coronary artery disease (OR: 2.82; 95% CI: 1.08-7.34; p = .034) were independent risk factors for non-LVRR. CONCLUSION LVRR also occurs in patients with MAVD, post-operative MR and coronary artery disease were independent risk factors for non-LVRR.
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Affiliation(s)
- Liangyan Huang
- Department of Ultrasound, Second Affiliated Hospital (Xinqiao Hospital), Army Medical University, Chongqing, China
| | - Xiaoyue Lai
- Department of Ultrasound, Second Affiliated Hospital (Xinqiao Hospital), Army Medical University, Chongqing, China
| | - Lei Xu
- Department of Ultrasound, Second Affiliated Hospital (Xinqiao Hospital), Army Medical University, Chongqing, China
| | - Ziling Zeng
- Department of Ultrasound, Second Affiliated Hospital (Xinqiao Hospital), Army Medical University, Chongqing, China
| | - Hongmei Xia
- Department of Ultrasound, Second Affiliated Hospital (Xinqiao Hospital), Army Medical University, Chongqing, China
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Zhang Z, Zhu J, Wu M, Neidlin M, Wu WT, Wu P. Computational modeling of hemodynamics and risk of thrombosis in the left atrial appendage using patient-specific blood viscosity and boundary conditions at the mitral valve. Biomech Model Mechanobiol 2023; 22:1447-1457. [PMID: 37389735 DOI: 10.1007/s10237-023-01731-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 05/23/2023] [Indexed: 07/01/2023]
Abstract
Hemodynamics play a vital role for the risk of thrombosis in the left atrial appendage (LAA) and left atrium (LA) for patients with atrial fibrillation. Accurate prediction of hemodynamics in the LA can provide important guidance for assessing the risk of thrombosis in the LAA. Patient specificity is a crucial factor in representing the true hemodynamic fields. In this study, we investigated the effects of blood rheology (as a function of hematocrit and shear rate), as well as patient-specific mitral valve (MV) boundary conditions (MV area and velocity profiles measured by ultrasound) on the hemodynamics and thrombosis potential of the LAA. Four scenarios were setup with different degrees of patient specificity. Though using a constant blood viscosity can classify the thrombus and non-thrombus patients for all the hemodynamic indicators, the risk of thrombosis was underestimated for all patients compared with patient-specific viscosities. The results with least patient specificities showed that patients prone to thrombosis predicted by three hemodynamic indicators were inconsistent with clinical observations. Moreover, though patients had the same MV inlet flow rate, different MV models lead to different trends in the risk of thrombosis in different patients. We also found that endothelial cell activation potential and relative residence time can effectively distinguish thrombus and non-thrombus patients for all the scenarios, relatively insensitive to patient specificities. Overall, the findings of this study provide useful insights on patients-specific hemodynamic simulations of the LA.
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Affiliation(s)
- Zijian Zhang
- Artificial Organ Technology Laboratory, School of Mechanical and Electrical Engineering, Soochow University, Suzhou, China
| | - Jiade Zhu
- Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, China
| | - Min Wu
- Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital (Guangdong Academy of Medical Sciences), Southern Medical University, Guangzhou, China.
| | - Michael Neidlin
- Department of Cardiovascular Engineering, Medical Faculty, Institute of Applied Medical Engineering, RWTH Aachen University, Aachen, Germany
| | - Wei-Tao Wu
- School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing, China
| | - Peng Wu
- Artificial Organ Technology Laboratory, School of Mechanical and Electrical Engineering, Soochow University, Suzhou, China.
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Didagelos M, Friderikos O, Ziakas A, David C, Sagris D, Pagiantza A, Karvounis H. Mitral valve geometrical echocardiographic analysis and 3D computational modeling of a normal mitral valve. Future Cardiol 2023; 19:453-467. [PMID: 37815033 DOI: 10.2217/fca-2021-0157] [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] [Indexed: 10/11/2023] Open
Abstract
Aim: This research aims to develop a consistent computational model of a normal mitral valve (MV) and describe mitral regurgitation (MR) geometry based on Carpentier's classification. Materials & methods: MV geometry was assessed by 2D transthoracic echocardiogram in 100 individuals. A 3D parametric geometric model of the MV was developed. A computational model of a normal MV was performed. Results: The simulation of the valve function was successfully accomplished and its kinematics was analyzed. Differences in geometry were revealed between normal and type III MR. Conclusion: 3D computational models of the normal MV can be constructed relying on standard measurements performed by 2D echocardiography. Certain geometrical differences exist among the normal and the most severe type of MR.
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Affiliation(s)
- Matthaios Didagelos
- 1st Cardiology Department, AHEPA University General Hospital, Aristotle University of Thessaloniki, 54636, Greece
| | - Orestis Friderikos
- Mechanical Engineering Department, International Hellenic University, Serres, 62124, Greece
| | - Antonios Ziakas
- 1st Cardiology Department, AHEPA University General Hospital, Aristotle University of Thessaloniki, 54636, Greece
| | - Constantine David
- Mechanical Engineering Department, International Hellenic University, Serres, 62124, Greece
| | - Dimitrios Sagris
- Mechanical Engineering Department, International Hellenic University, Serres, 62124, Greece
| | - Areti Pagiantza
- 1st Cardiology Department, AHEPA University General Hospital, Aristotle University of Thessaloniki, 54636, Greece
| | - Haralambos Karvounis
- 1st Cardiology Department, AHEPA University General Hospital, Aristotle University of Thessaloniki, 54636, Greece
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7
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Lancini D, Smith C, Elkhateeb O, Sapp J, Parkash R. Leadless Micra pacemaker implantation in patient with previous Senning procedure for dextro-transposition of the great arteries. Acta Cardiol 2023; 78:357-361. [PMID: 36803008 DOI: 10.1080/00015385.2023.2176043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
Leadless pacemakers have been developed with key advantages over traditional transvenous pacemakers by substantially mitigating the risks of device infection and lead related complications, and providing an alternative pacing strategy in patients with barriers to superior venous access. The Medtronic Micra leadless pacing system is designed for implantation through a femoral venous approach across the tricuspid valve, via Nitinol tine fixation into the trabeculated subpulmonic right ventricle. Patients with surgically corrected dextro-transposition of the great arteries (d-TGA) have an increased risk of pacing requirement. There is limited published experience of implantation of leadless Micra pacemakers in this population, with key challenges relating to trans-baffle access, and deployment of the device into the less trabeculated subpulmonic left ventricle. Here we describe a case report of leadless Micra implantation in a 49 year old male with d-TGA and Senning procedure in childhood, who required pacing for symptomatic sinus node disease, with anatomic barriers to transvenous pacing. Micra implantation was successfully performed following careful consideration of patient anatomy, including the utilisation of 3D modelling to guide the implantation procedure.
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Affiliation(s)
- Daniel Lancini
- Department of Cardiology, Queen Elizabeth II Health Sciences Centre, Halifax, Nova Scotia, Canada
| | - Corey Smith
- Department of Cardiology, Queen Elizabeth II Health Sciences Centre, Halifax, Nova Scotia, Canada
| | - Osama Elkhateeb
- Department of Cardiology, Queen Elizabeth II Health Sciences Centre, Halifax, Nova Scotia, Canada
| | - John Sapp
- Department of Cardiology, Queen Elizabeth II Health Sciences Centre, Halifax, Nova Scotia, Canada
| | - Ratika Parkash
- Department of Cardiology, Queen Elizabeth II Health Sciences Centre, Halifax, Nova Scotia, Canada
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8
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Gu K, Yan S, Wu X. Influence of pulsating intracardiac blood flow on radiofrequency catheter ablation outcomes in an anatomy-based atrium model. Int J Hyperthermia 2022; 39:1064-1077. [PMID: 35993225 DOI: 10.1080/02656736.2022.2108149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022] Open
Abstract
BACKGROUND Highly consistent cardiac ablation outcomes through radiofrequency catheter ablation (RFCA) under pulsatile and constant flow profiles (PP&CP) of intracardiac blood were previously indicated by computer modeling, with simplified geometry and lossless receipt of inflow for ablation catheters. This study aimed to further investigate the effects of intracardiac blood pulsatility in an anatomy-based atrium model. METHODS Four pulmonary veins were blood inflows at 10 mm Hg. The mitral valve was the outflow, with PP based on pulsatile velocity curve from clinical measurements, and CP was obtained by averaging the velocity curve under PP over an ablation time of 30 s. A numerical comparison between ablation results under PP and CP, without experimental validation, was performed. RESULTS Temperature fluctuations persisted in mid-myocardium, and most clearly in blood and endocardium under PP. At a constant power of 20 W, marked differences in ablation outcome between PP and CP occurred in the middle of unilateral pulmonary veins and the posterior wall of the left atrium (LA) where the blood velocities were significantly decreased under CP. The mid-myocardial, blood and endocardial temperatures, as well as the effective lesion volume at the former position, were decreased by 4.1%, 15%, 13.6%, and 13.8%, respectively under PP. The extents for the latter position were 11%, 22%, 22.5%, and 55.6%, respectively. CONCLUSION Intracardiac flow pulsatility causes a greater reduction in blood and endocardial temperatures at ablation sites away from the main bloodstream, effective cooling of which is more likely to rely on blood velocities approaching peak PP values.
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Affiliation(s)
- Kaihao Gu
- Centre for Biomedical Engineering, School of Information Science and Technology, Fudan University, Shanghai, China
| | - Shengjie Yan
- Centre for Biomedical Engineering, School of Information Science and Technology, Fudan University, Shanghai, China
| | - Xiaomei Wu
- Centre for Biomedical Engineering, School of Information Science and Technology, Fudan University, Shanghai, China.,Academy for Engineering and Technology, Fudan University, Shanghai, China.,Key Laboratory of Medical Imaging Computing and Computer Assisted Intervention (MICCAI) of Shanghai, Fudan University, Shanghai, China.,Shanghai Engineering Research Centre of Assistive Devices, Shanghai, China.,Yiwu Research Institute of Fudan University, Yiwu, China
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9
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Muñoz-RodrÃguez R, Duque-González MA, Igareta-Herraiz AT, Di Silvestre M, Izquierdo-Gómez MM, Baeza-Garzón F, Barragán-Acea A, Bosa-Ojeda F, Lacalzada-Almeida J. Practical Echocardiographic Approach of the Regurgitant Mitral Valve Assessment. Diagnostics (Basel) 2022; 12:diagnostics12071717. [PMID: 35885621 PMCID: PMC9319327 DOI: 10.3390/diagnostics12071717] [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: 06/13/2022] [Revised: 07/03/2022] [Accepted: 07/12/2022] [Indexed: 11/27/2022] Open
Abstract
Mitral regurgitation is the second-most frequent valvular heart disease in Europe after degenerative aortic stenosis. It is associated with significant morbidity and mortality, and its prevalence is expected to increase with population aging. Echocardiography is the first diagnostic approach to assess its severity, constituting a challenging process in which a multimodality evaluation, integrating quantitative, semiquantitative and qualitative methods, as well as a detailed evaluation of the morphology and function of both left ventricle and atria is the key. In this review, we would like to provide a practical diagnosis approach on the mitral valve regurgitation mechanism, severity quantification, and planning of future therapeutic options.
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10
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Gaidulis G, Suresh KS, Xu D, Padala M. Patient-Specific Three-Dimensional Ultrasound Derived Computational Modeling of the Mitral Valve. Ann Biomed Eng 2022; 50:847-859. [PMID: 35380321 PMCID: PMC10826907 DOI: 10.1007/s10439-022-02960-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Accepted: 03/27/2022] [Indexed: 11/01/2022]
Abstract
Several new techniques to repair the mitral valve affected by functional mitral regurgitation are in development. However, due to the heterogeneity of valve lesions between patients, predicting the outcomes of novel treatment approaches is challenging. We present a patient-specific, 3D ultrasound-derived computational model of the mitral valve for procedure planning, that faithfully mimics the pathological valve dynamics. 3D ultrasound images were obtained in three pigs induced with heart failure and which developed functional mitral regurgitation. For each case, images were segmented, and finite element model of mitral valve was constructed. Annular and papillary muscle dynamics were extracted and imposed as kinematic boundary conditions, and the chordae were pre-strained to induce valve tethering. Valve closure was simulated by applying physiologic transvalvular pressure on the leaflets. Agreement between simulation results and truth datasets was confirmed, with accurate location of regurgitation jets and coaptation defects. Inclusion of kinematic patient-specific boundary conditions was necessary to achieve these results, whereas use of idealized boundary conditions deviated from the truth dataset. Due to the impact of boundary conditions on the model, the effect of repair strategies on valve closure varied as well, indicating that our approach of using patient-specific boundary conditions for mitral valve modeling is valid.
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Affiliation(s)
- Gediminas Gaidulis
- Structural Heart Research and Innovation Laboratory, Carlyle Fraser Heart Center at Emory University Hospital Midtown, 380B Northyards Blvd NW, Atlanta, GA, 30313, USA
- Division of Cardiothoracic Surgery, Emory University School of Medicine, Atlanta, GA, USA
| | - Kirthana Sreerangathama Suresh
- Structural Heart Research and Innovation Laboratory, Carlyle Fraser Heart Center at Emory University Hospital Midtown, 380B Northyards Blvd NW, Atlanta, GA, 30313, USA
| | - Dongyang Xu
- Structural Heart Research and Innovation Laboratory, Carlyle Fraser Heart Center at Emory University Hospital Midtown, 380B Northyards Blvd NW, Atlanta, GA, 30313, USA
| | - Muralidhar Padala
- Structural Heart Research and Innovation Laboratory, Carlyle Fraser Heart Center at Emory University Hospital Midtown, 380B Northyards Blvd NW, Atlanta, GA, 30313, USA.
- Division of Cardiothoracic Surgery, Emory University School of Medicine, Atlanta, GA, USA.
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11
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Pandya PK, Wilkerson RJ, Imbrie-Moore AM, Zhu Y, Marin-Cuartas M, Park MH, Woo YJ. Quantitative Biomechanical Optimization of Neochordal Implantation Location on Mitral Leaflets during Valve Repair. JTCVS Tech 2022; 14:89-93. [PMID: 35967240 PMCID: PMC9366621 DOI: 10.1016/j.xjtc.2022.05.008] [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: 12/09/2021] [Revised: 04/01/2022] [Accepted: 05/10/2022] [Indexed: 11/01/2022] Open
Abstract
Objective Methods Results Conclusions
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12
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Hegeman RMJJ, Gheorghe LL, de Kroon TL, van Putte BP, Swaans MJ, Klein P. State-of-the-Art Review: Technical and Imaging Considerations in Novel Transapical and Port-Access Mitral Valve Chordal Repair for Degenerative Mitral Regurgitation. Front Cardiovasc Med 2022; 9:850700. [PMID: 35497995 PMCID: PMC9039516 DOI: 10.3389/fcvm.2022.850700] [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: 01/08/2022] [Accepted: 03/14/2022] [Indexed: 12/02/2022] Open
Abstract
Degenerative mitral regurgitation (DMR) based on posterior leaflet prolapse is the most frequent type of organic mitral valve disease and has proven to be durably repairable in most cases by chordal repair techniques either by conventional median sternotomy or by less invasive approaches both utilizing extracorporeal circulation and cardioplegic myocardial arrest. Recently, several novel transapical chordal repair techniques specifically targeting the posterior leaflet have been developed as a far less invasive and beating heart (off-pump) alternative to port-access mitral repair. In order to perform a safe and effective minimally invasive mitral chordal repair, thorough knowledge of the anatomy of the mitral valve apparatus and adequate use of multimodality imaging both pre- and intraoperatively are fundamental. In addition, comprehensive understanding of the available novel devices, their delivery systems and the individual procedural steps are required.
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Affiliation(s)
- Romy M. J. J. Hegeman
- Department of Cardiothoracic Surgery, St. Antonius Hospital, Nieuwegein, Netherlands
- *Correspondence: Romy M. J. J. Hegeman,
| | | | - Thomas L. de Kroon
- Department of Cardiothoracic Surgery, St. Antonius Hospital, Nieuwegein, Netherlands
| | - Bart P. van Putte
- Department of Cardiothoracic Surgery, St. Antonius Hospital, Nieuwegein, Netherlands
| | - Martin J. Swaans
- Department of Cardiology, St. Antonius Hospital, Nieuwegein, Netherlands
| | - Patrick Klein
- Department of Cardiothoracic Surgery, St. Antonius Hospital, Nieuwegein, Netherlands
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13
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OUP accepted manuscript. Eur J Cardiothorac Surg 2022; 62:6547516. [DOI: 10.1093/ejcts/ezac133] [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: 09/20/2021] [Revised: 01/26/2022] [Accepted: 02/14/2022] [Indexed: 11/14/2022] Open
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14
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Bui HT, Khair N, Yeats B, Gooden S, James SP, Dasi LP. Transcatheter Heart Valves: A Biomaterials Perspective. Adv Healthc Mater 2021; 10:e2100115. [PMID: 34038627 DOI: 10.1002/adhm.202100115] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 04/23/2021] [Indexed: 11/11/2022]
Abstract
Heart valve disease is prevalent throughout the world, and the number of heart valve replacements is expected to increase rapidly in the coming years. Transcatheter heart valve replacement (THVR) provides a safe and minimally invasive means for heart valve replacement in high-risk patients. The latest clinical data demonstrates that THVR is a practical solution for low-risk patients. Despite these promising results, there is no long-term (>20 years) durability data on transcatheter heart valves (THVs), raising concerns about material degeneration and long-term performance. This review presents a detailed account of the materials development for THVRs. It provides a brief overview of THVR, the native valve properties, the criteria for an ideal THV, and how these devices are tested. A comprehensive review of materials and their applications in THVR, including how these materials are fabricated, prepared, and assembled into THVs is presented, followed by a discussion of current and future THVR biomaterial trends. The field of THVR is proliferating, and this review serves as a guide for understanding the development of THVs from a materials science and engineering perspective.
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Affiliation(s)
- Hieu T. Bui
- Department of Biomedical Engineering Georgia Institute of Technology 387 Technology Cir NW Atlanta GA 30313 USA
| | - Nipa Khair
- School of Advanced Materials Discovery Colorado State University 700 Meridian Ave Fort Collins CO 80523 USA
| | - Breandan Yeats
- Department of Biomedical Engineering Georgia Institute of Technology 387 Technology Cir NW Atlanta GA 30313 USA
| | - Shelley Gooden
- Department of Biomedical Engineering Georgia Institute of Technology 387 Technology Cir NW Atlanta GA 30313 USA
| | - Susan P. James
- School of Advanced Materials Discovery Colorado State University 700 Meridian Ave Fort Collins CO 80523 USA
| | - Lakshmi Prasad Dasi
- Department of Biomedical Engineering Georgia Institute of Technology 387 Technology Cir NW Atlanta GA 30313 USA
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15
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de Oliveira DC, Espino DM, Deorsola L, Mynard JP, Rajagopal V, Buchan K, Dawson D, Shepherd DET. A toolbox for generating scalable mitral valve morphometric models. Comput Biol Med 2021; 135:104628. [PMID: 34246162 DOI: 10.1016/j.compbiomed.2021.104628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 06/25/2021] [Accepted: 07/02/2021] [Indexed: 11/26/2022]
Abstract
The mitral valve is a complex anatomical structure, whose shape is key to several traits of its function and disease, being crucial for the success of surgical repair and implantation of medical devices. The aim of this study was to develop a parametric, scalable, and clinically useful model of the mitral valve, enabling the biomechanical evaluation of mitral repair techniques through finite element simulations. MATLAB was used to parameterize the valve: the annular boundary was sampled from a porcine mitral valve mesh model and landmark points and relevant boundaries were selected for the parameterization of leaflets using polynomial fitting. Several geometric parameters describing the annulus, leaflet shape and papillary muscle position were implemented and used to scale the model according to patient dimensions. The developed model, available as a toolbox, allows for the generation of a population of models using patient-specific dimensions obtained from medical imaging or averaged dimensions evaluated from empirical equations based on the Golden Proportion. The average model developed using this framework accurately represents mitral valve shapes, associated with relative errors reaching less than 10% for annular and leaflet length dimensions, and less than 24% in comparison with clinical data. Moreover, model generation takes less than 5Â min of computing time, and the toolbox can account for individual morphological variations and be employed to evaluate mitral valve biomechanics; following further development and validation, it will aid clinicians when choosing the best patient-specific clinical intervention and improve the design process of new medical devices.
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Affiliation(s)
- Diana C de Oliveira
- Department of Mechanical Engineering, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK.
| | - Daniel M Espino
- Department of Mechanical Engineering, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Luca Deorsola
- Paedriatic Cardiac Surgery, Ospedale Infantile Regina Margherita Sant Anna, Turin, 10126, Italy
| | - Jonathan P Mynard
- Department of Biomedical Engineering, The University of Melbourne, Melbourne, VIC, 3010, Australia; Heart Research, Murdoch Children's Research Institute, Royal Children's Hospital, Melbourne, VIC, 3052, Australia; Department of Paediatrics, The University of Melbourne, Melbourne, VIC, 3010, Australia; Department of Cardiology, Royal Children's Hospital, Melbourne, VIC, 3052, Australia
| | - Vijay Rajagopal
- Department of Biomedical Engineering, The University of Melbourne, Melbourne, VIC, 3010, Australia
| | - Keith Buchan
- Department of Cardiothoracic Surgery, Aberdeen Royal Infirmary, Aberdeen, AB24 2ZN, Scotland, UK
| | - Dana Dawson
- School of Medicine, University of Aberdeen, Aberdeen, AB25 2ZD, Scotland, UK; Cardiology Department, Aberdeen Royal Infirmary, Aberdeen, AB25 2ZN, Scotland, UK
| | - Duncan E T Shepherd
- Department of Mechanical Engineering, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
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16
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Didagelos M, Friderikos O. Evaluation of mitral valve regurgitation according to Carpentier's classification and development of 3D FEM models. Hippokratia 2021; 25:94. [PMID: 35937510 PMCID: PMC9347342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Affiliation(s)
- M Didagelos
- 1st Cardiology Department, AHEPA University General Hospital, Aristotle University of Thessaloniki, Greece
| | - O Friderikos
- Mechanical Engineering Department, International Hellenic University, Serres, Greece
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17
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Impact of left atrial appendage location on risk of thrombus formation in patients with atrial fibrillation. Biomech Model Mechanobiol 2021; 20:1431-1443. [PMID: 33755847 DOI: 10.1007/s10237-021-01454-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 03/10/2021] [Indexed: 02/07/2023]
Abstract
Most strokes in patients with atrial fibrillation (AF) are thought to arise from thrombus formation in the left atrial appendage (LAA). Assessing the hemodynamics in LAA and left atrium (LA) may provide some insights in the evaluation of the risk of thrombus formation. This study aims to find out the impact of different LAA locations with respect of LA on the risk of thrombus formation within LAA in patients with AF. Three different LAA locations at LA were modeled and a fully coupled fluid-structure interaction analysis was performed. A discrete phase method was used for particle residence analysis to evaluate risk of the thrombus formation. The results showed that LAA positions on the LA affected the LAA flow velocity distribution, passive contraction ability, and particle residence. In particular, the left pulmonary veins (PVs) had a greater influence on the LAA hemodynamics than the right PVs. The LAA had the lowest contractibility when it was located between left superior and left inferior PVs, and in this case, a larger number of particles were resided, which indicated a higher risk of thrombus formation. The present work provides a quantitative way to evaluate the risk of thrombus formation within LAA in patients with AF.
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18
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Rutland J, Tecson KM, Assar MD. Leadless ventricular pacemaker implant with atrial sensing in levo-transposition of the great arteries. HeartRhythm Case Rep 2021; 7:220-223. [PMID: 34026500 PMCID: PMC8128991 DOI: 10.1016/j.hrcr.2021.01.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Affiliation(s)
| | - Kristen M Tecson
- Baylor Heart and Vascular Institute, Dallas, Texas.,Texas A&M College of Medicine Health Science Center, Dallas, Texas
| | - Manish D Assar
- Baylor Heart & Vascular Hospital, Dallas, Texas.,Texas A&M College of Medicine Health Science Center, Dallas, Texas
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19
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Constable M, Northeast R, Lawless BM, Burton HE, Gramigna V, Goh KL, Buchan KG, Espino DM. Mechanical testing of glutaraldehyde cross-linked mitral valves. Part two: Elastic and viscoelastic properties of chordae tendineae. Proc Inst Mech Eng H 2020; 235:291-299. [PMID: 33243079 DOI: 10.1177/0954411920975938] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The aim of this study was to assess whether the mechanical properties of mitral valve chordae tendineae are sensitive to being cross-linked under load. A total 64 chordae were extracted from eight porcine hearts. Two chordae (posterior basal) from each heart were subjected to uniaxial ramp testing and six chordae (two strut, two anterior basal and two posterior basal) were subjected to dynamic mechanical analysis over frequencies between 0.5 and 10 Hz. Chordae were either cross-linked in tension or cross-linked in the absence of loading. Chordae cross-linked under load transitioned from high to low extension at a lower strain than cross-linked unloaded chordae (0.07 cf. 0.22), with greater pre-transitional (30.8 MPa cf. 5.78 MPa) and post-transitional (139 MPa cf. 74.1 MPa) moduli. The mean storage modulus of anterior strut chordae ranged from 48 to 54 MPa for cross-linked unloaded chordae, as compared to 53-61 MPa cross-linked loaded chordae. The mean loss modulus of anterior strut chordae ranged from 2.3 to 2.9 MPa for cross-linked unloaded chordae, as compared to 3.8-4.8 MPa cross-linked loaded chordae. The elastic and viscoelastic properties of chordae following glutaraldehyde cross-linking are dependent on the inclusion/exclusion of loading during the cross-linking process; with loading increasing the magnitude of the material properties measured.
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Affiliation(s)
- Matthew Constable
- Department of Mechanical Engineering, University of Birmingham, Birmingham, UK
| | - Rhiannon Northeast
- Department of Mechanical Engineering, University of Birmingham, Birmingham, UK
| | - Bernard M Lawless
- Department of Mechanical Engineering, University of Birmingham, Birmingham, UK.,Filament PD, Level 4 - Skypark 3, Skypark, Glasgow, UK
| | - Hanna E Burton
- Department of Mechanical Engineering, University of Birmingham, Birmingham, UK
| | - Vera Gramigna
- University of Magna Graecia, Catanzaro, Italy.,IBFM, National Research Council, Germaneto, Catanzaro, Italy
| | - Kheng Lim Goh
- Department of Mechanical Engineering, University of Newcastle, Singapore
| | - Keith G Buchan
- Department of Cardio-thoracic Surgery, Aberdeen Royal Infirmary, Forresterhill, Aberdeen, UK
| | - Daniel M Espino
- Department of Mechanical Engineering, University of Birmingham, Birmingham, UK
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20
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Northeast R, Constable M, Burton HE, Lawless BM, Gramigna V, Lim Goh K, Buchan KG, Espino DM. Mechanical testing of glutaraldehyde cross-linked mitral valves. Part one: In vitro mechanical behaviour. Proc Inst Mech Eng H 2020; 235:281-290. [PMID: 33231114 DOI: 10.1177/0954411920975894] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The aim of this study was to perform an initial assessment, in vitro, of the feasibility of using a glutaraldehyde cross-linked porcine mitral valve to retain acute functionality, focusing on assessing mitral regurgitation. Six porcine hearts were tested using an in vitro simulator. Testing was repeated following cross-linking of mitral valves; where cross-linking was achieved by placing them in a glutaraldehyde solution. The simulator enabled systolic pressure on the ventricular side of the valve to be mimicked. Following testing, mitral valve leaflets underwent Scanning Electron Microscopy of the ventricular surface of both the anterior and posterior leaflets (1 cm2 samples). The peak pressure withstood by cross-linked valves was significantly lower than for untreated valves (108 mmHg cf. 128 mmHg for untreated valves; p  < 0.05). The peak pressure was typically reached 0.5 s later than for the untreated valve. While both cross-linked and untreated valves exhibited endothelium denudation, the unfixed valve had less endothelial loss. Glutaraldehyde cross-linking of porcine mitral valves may be of potential value in assessing improved bioprosthetic mitral valve replacements. However, a more immobile valve exhibiting endothelial denudation (i.e. sclerosis) was a possible concerns identified following in vitro acute assessment.
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Affiliation(s)
- Rhiannon Northeast
- Department of Mechanical Engineering, University of Birmingham, Birmingham, UK
| | - Matthew Constable
- Department of Mechanical Engineering, University of Birmingham, Birmingham, UK
| | - Hanna E Burton
- Department of Mechanical Engineering, University of Birmingham, Birmingham, UK
| | - Bernard M Lawless
- Department of Mechanical Engineering, University of Birmingham, Birmingham, UK.,Filament PD, Level 4 - Skypark 3, Skypark, Glasgow, UK
| | - Vera Gramigna
- University of Magna Graecia, Catanzaro, Italy.,IBFM, National Research Council, Germaneto, Catanzaro, Italy
| | - Kheng Lim Goh
- Department of Mechanical Engineering, University of Newcastle, Singapore
| | - Keith G Buchan
- Department of Cardio-thoracic Surgery, Aberdeen Royal Infirmary, Forresterhill, Aberdeen, UK
| | - Daniel M Espino
- Department of Mechanical Engineering, University of Birmingham, Birmingham, UK
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21
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Taylor S, Buchan KG, Espino DM. The role of strut chordae in mitral valve competence during annular dilation. Perfusion 2020; 36:253-260. [PMID: 32693675 PMCID: PMC8041452 DOI: 10.1177/0267659120941340] [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] [Indexed: 12/11/2022]
Abstract
Strut chordae, on their own, are not typically thought to aid mitral valve competence. The aim of this study is to assess whether strut chordae aid mitral valve competence during acute annular dilation. Twelve porcine hearts were dissected and tested using an in vitro simulator, with the mitral annulus tested in either a 'normal' or a dilated configuration. The normal configuration included a diameter of 30 mm, a posterior leaflet 'radius' of 15 mm and a commissural corner 'radius' of 7.5 mm; the dilated annular template instead used dimensions of 50 mm, 25 mm and 12.5 mm, respectively. Each mitral valve underwent ten repeat tests with a target systolic pressure of 100 mmHg. No significant difference in the pressure was detected between the dilated and regular annuli for the mitral valves tested (95 ± 3 mmHg cf. 95 ± 2 mmHg). However, the volume of regurgitation for a dilated annulus was 28 ml greater than for a valve with a normal annulus. Following severing of strut chordae, there was a significant reduction in the systolic pressure withstood before regurgitation by mitral valves with dilated annuli (60 ± 29 mmHg cf. 95 ± 2 mmHg for normal annular dimensions; p < 0.05). In conclusion, strut chordae tendineae may play a role in aiding mitral valve competence during pathophysiology.
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Affiliation(s)
- Samuel Taylor
- Department of Mechanical Engineering, University of Birmingham, Birmingham, UK
| | - Keith G Buchan
- Department of Cardiothoracic Surgery, Aberdeen Royal Infirmary, Aberdeen, UK
| | - Daniel M Espino
- Department of Mechanical Engineering, University of Birmingham, Birmingham, UK
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22
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Taylor S, Buchan KG, Espino DM. The role of strut chordae in mitral valve competence during annular dilation. Perfusion 2020. [PMID: 32693675 DOI: 10.1177/0267659120941340.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Strut chordae, on their own, are not typically thought to aid mitral valve competence. The aim of this study is to assess whether strut chordae aid mitral valve competence during acute annular dilation. Twelve porcine hearts were dissected and tested using an in vitro simulator, with the mitral annulus tested in either a 'normal' or a dilated configuration. The normal configuration included a diameter of 30 mm, a posterior leaflet 'radius' of 15 mm and a commissural corner 'radius' of 7.5 mm; the dilated annular template instead used dimensions of 50 mm, 25 mm and 12.5 mm, respectively. Each mitral valve underwent ten repeat tests with a target systolic pressure of 100 mmHg. No significant difference in the pressure was detected between the dilated and regular annuli for the mitral valves tested (95 ± 3 mmHg cf. 95 ± 2 mmHg). However, the volume of regurgitation for a dilated annulus was 28 ml greater than for a valve with a normal annulus. Following severing of strut chordae, there was a significant reduction in the systolic pressure withstood before regurgitation by mitral valves with dilated annuli (60 ± 29 mmHg cf. 95 ± 2 mmHg for normal annular dimensions; p < 0.05). In conclusion, strut chordae tendineae may play a role in aiding mitral valve competence during pathophysiology.
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Affiliation(s)
- Samuel Taylor
- Department of Mechanical Engineering, University of Birmingham, Birmingham, UK
| | - Keith G Buchan
- Department of Cardiothoracic Surgery, Aberdeen Royal Infirmary, Aberdeen, UK
| | - Daniel M Espino
- Department of Mechanical Engineering, University of Birmingham, Birmingham, UK
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