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Balasubramanya A, Maes L, Rega F, Mazzi V, Morbiducci U, Famaey N, Degroote J, Segers P. Hemodynamics and wall shear metrics in a pulmonary autograft: Comparing a fluid-structure interaction and computational fluid dynamics approach. Comput Biol Med 2024; 176:108604. [PMID: 38761502 DOI: 10.1016/j.compbiomed.2024.108604] [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: 01/23/2024] [Revised: 05/02/2024] [Accepted: 05/11/2024] [Indexed: 05/20/2024]
Abstract
OBJECTIVE In young patients, aortic valve disease is often treated by placement of a pulmonary autograft (PA) which adapts to its new environment through growth and remodeling. To better understand the hemodynamic forces acting on the highly distensible PA in the acute phase after surgery, we developed a fluid-structure interaction (FSI) framework and comprehensively compared hemodynamics and wall shear-stress (WSS) metrics with a computational fluid dynamic (CFD) simulation. METHODS The FSI framework couples a prestressed non-linear hyperelastic arterial tissue model with a fluid model using the in-house coupling code CoCoNuT. Geometry, material parameters and boundary conditions are based on in-vivo measurements. Hemodynamics, time-averaged WSS (TAWSS), oscillatory shear index (OSI) and topological shear variation index (TSVI) are evaluated qualitatively and quantitatively for 3 different sheeps. RESULTS Despite systolic-to-diastolic volumetric changes of the PA in the order of 20 %, the point-by-point correlation of TAWSS and OSI obtained through CFD and FSI remains high (r > 0.9, p < 0.01) for TAWSS and (r > 0.8, p < 0.01) for OSI). Instantaneous WSS divergence patterns qualitatively preserve similarities, but large deformations of the PA leads to a decrease of the correlation between FSI and CFD resolved TSVI (r < 0.7, p < 0.01). Moderate co-localization between FSI and CFD is observed for low thresholds of TAWSS and high thresholds of OSI and TSVI. CONCLUSION FSI might be warranted if we were to use the TSVI as a mechano-biological driver for growth and remodeling of PA due to varying intra-vascular flow structures and near wall hemodynamics because of the large expansion of the PA.
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Affiliation(s)
| | - Lauranne Maes
- Department of Mechanical Engineering, KU Leuven, Leuven, Belgium
| | - Filip Rega
- Cardiac Surgery, Department of Cardiovascular Sciences, KU Leuven, Belgium
| | - Valentina Mazzi
- PolitoBIOMed Lab, Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Turin, Italy
| | - Umberto Morbiducci
- PolitoBIOMed Lab, Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Turin, Italy
| | - Nele Famaey
- Department of Mechanical Engineering, KU Leuven, Leuven, Belgium
| | - Joris Degroote
- Department of Electromechanical Systems and Metal Engineering, Ghent University, Ghent, Belgium
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Maes L, Vervenne T, Van Hoof L, Jones EAV, Rega F, Famaey N. Computational modeling reveals inflammation-driven dilatation of the pulmonary autograft in aortic position. Biomech Model Mechanobiol 2023; 22:1555-1568. [PMID: 36764979 DOI: 10.1007/s10237-023-01694-6] [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: 05/16/2022] [Accepted: 01/17/2023] [Indexed: 02/12/2023]
Abstract
The pulmonary autograft in the Ross procedure, where the aortic valve is replaced by the patient's own pulmonary valve, is prone to failure due to dilatation. This is likely caused by tissue degradation and maladaptation, triggered by the higher experienced mechanical loads in aortic position. In order to further grasp the causes of dilatation, this study presents a model for tissue growth and remodeling of the pulmonary autograft, using the homogenized constrained mixture theory and equations for immuno- and mechano-mediated mass turnover. The model outcomes, compared to experimental data from an animal model of the pulmonary autograft in aortic position, show that inflammation likely plays an important role in the mass turnover of the tissue constituents and therefore in the autograft dilatation over time. We show a better match and prediction of long-term outcomes assuming immuno-mediated mass turnover, and show that there is no linear correlation between the stress-state of the material and mass production. Therefore, not only mechanobiological homeostatic adaption should be taken into account in the development of growth and remodeling models for arterial tissue in similar applications, but also inflammatory processes.
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Affiliation(s)
- Lauranne Maes
- Biomechanics Section, Mechanical Engineering Department, KU Leuven, Celestijnenlaan 300 box 2419, 3001, Leuven, Belgium.
| | - Thibault Vervenne
- Biomechanics Section, Mechanical Engineering Department, KU Leuven, Celestijnenlaan 300 box 2419, 3001, Leuven, Belgium
| | - Lucas Van Hoof
- Cardiac Surgery, Department of Cardiovascular Sciences, KU Leuven, UZ Herestraat 49 box 276, 3000, Leuven, Belgium
| | - Elizabeth A V Jones
- Centre for Molecular and Vascular Biology, KU Leuven, UZ Herestraat 49 box 911, 3000, Leuven, Belgium
| | - Filip Rega
- Cardiac Surgery, Department of Cardiovascular Sciences, KU Leuven, UZ Herestraat 49 box 276, 3000, Leuven, Belgium
| | - Nele Famaey
- Biomechanics Section, Mechanical Engineering Department, KU Leuven, Celestijnenlaan 300 box 2419, 3001, Leuven, Belgium
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Honan KA, Hassan S, Deswal A, Herrmann J, Song J, Monlezun D, Halperin D, Mahvash A, Dasari A, Koutroumpakis E, Akay M, Balanescu DV, de Armas IS, Patel M, Nathan S, Kar B, Marmagkiolis K, Lopez-Mattei J, Patel J, Gregoric I, Yao J, Iliescu CA. Bioprosthetic valve monitoring in patients with carcinoid heart disease. Front Cardiovasc Med 2023; 9:1072890. [PMID: 36712267 PMCID: PMC9878394 DOI: 10.3389/fcvm.2022.1072890] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 12/22/2022] [Indexed: 01/14/2023] Open
Abstract
Background Carcinoid heart disease (CnHD) is a frequent cause of morbidity and mortality in patients with neuroendocrine tumors and carcinoid syndrome. Although valve replacement surgery appears to decrease all-cause mortality in patients with advanced CnHD, few studies have investigated the outcomes of patients after valve replacement. Methods We conducted a multi-institution retrospective registry of patients who received both tricuspid and pulmonic bioprosthetic valve (TV/PV) replacements for advanced CnHD from November 2005 to March 2021. Patients were followed post-operatively with echocardiographic studies every 3 months. Carcinoid valvular heart disease scores were used to monitor valve degeneration. Neuroendocrine tumor treatment, their administration times, and associations with echocardiographic findings were recorded. Results Of 87 patients with CnHD, 22 patients underwent simultaneous surgical TV and PV replacement. In 6 patients (27.3%), increased PV Vmax was the first echocardiographic manifestation of valve degeneration in the setting of occult neurohormonal release. Post-operative telotristat ethyl and peptide receptor radionuclide therapy appeared to stabilize PV Vmax. The PV Vmax showed consistent elevation in the entire patient population when compared to baseline, while bioprosthetic TV echocardiographic parameters were relatively unchanged throughout. Post-operative warfarin therapy did not affect the rate of PV degeneration, and no major bleeding was recorded during or after post-operative anticoagulation therapy. Conclusion Bioprosthetic valve degeneration is common in CnHD. Monitoring with echocardiographic studies every 3 months, focusing on PV velocities, could identify patients with occult disease that very likely promotes valve degeneration. Novel neuroendocrine tumor therapies may have a beneficial impact on valve degeneration.
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Affiliation(s)
- Kevin A. Honan
- Department of Internal Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, United States
| | - Saamir Hassan
- Department of Cardiology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Anita Deswal
- Department of Cardiology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Joerg Herrmann
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN, United States
| | - Juhee Song
- Department of Cardiology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Dominique Monlezun
- Department of Internal Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, United States
| | - Daniel Halperin
- Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Armeen Mahvash
- Division of Diagnostic Imaging, Department of Interventional Radiology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Arvind Dasari
- Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Efstratios Koutroumpakis
- Department of Cardiology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Mehmet Akay
- Department of Cardiothoracic Surgery, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, United States
| | - Dinu-Valentin Balanescu
- Department of Cardiology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Ismael Salas de Armas
- Department of Cardiothoracic Surgery, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, United States
| | - Manish Patel
- Department of Cardiothoracic Surgery, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, United States
| | - Sriram Nathan
- Center for Advanced Heart Failure, Memorial Hermann Hospital, Heart and Vascular Institute, Texas Medical Center, Houston, TX, United States
| | - Biswajit Kar
- Center for Advanced Heart Failure, Memorial Hermann Hospital, Heart and Vascular Institute, Texas Medical Center, Houston, TX, United States
| | - Konstantinos Marmagkiolis
- Department of Cardiology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Juan Lopez-Mattei
- Department of Cardiology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Jay Patel
- Department of Cardiothoracic Surgery, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, United States
| | - Igor Gregoric
- Department of Cardiothoracic Surgery, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, United States
| | - James Yao
- Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Cezar A. Iliescu
- Department of Cardiology, The University of Texas MD Anderson Cancer Center, Houston, TX, United States,*Correspondence: Cezar A. Iliescu,
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Biomechanics of Pulmonary Autograft as Living Tissue: A Systematic Review. Bioengineering (Basel) 2022; 9:bioengineering9090456. [PMID: 36135002 PMCID: PMC9495771 DOI: 10.3390/bioengineering9090456] [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: 07/27/2022] [Revised: 09/01/2022] [Accepted: 09/04/2022] [Indexed: 11/17/2022] Open
Abstract
Introduction: The choice of valve substitute for aortic valve surgery is tailored to the patient with specific indications and contraindications to consider. The use of an autologous pulmonary artery (PA) with a simultaneous homograft in the pulmonary position is called a Ross procedure. It permits somatic growth and the avoidance of lifelong anticoagulation. Concerns remain on the functionality of a pulmonary autograft in the aortic position when exposed to systemic pressure. Methods: A literature review was performed incorporating the following databases: Pub Med (1996 to present), Ovid Medline (1958 to present), and Ovid Embase (1982 to present), which was run on 1 January 2022 with the following targeted words: biomechanics of pulmonary autograft, biomechanics of Ross operation, aortic valve replacement and pulmonary autograph, aortic valve replacement and Ross procedure. To address the issues with heterogeneity, studies involving the pediatric cohort were also analyzed separately. The outcomes measured were early- and late-graft failure alongside mortality. Results: a total of 8468 patients were included based on 40 studies (7796 in pediatric cohort and young adult series and 672 in pediatric series). There was considerable experience accumulated by various institutions around the world. Late rates of biomechanical failure and mortality were low and comparable to the general population. The biomechanical properties of the PA were superior to other valve substitutes. Mathematical and finite element analysis studies have shown the potential stress-shielding effects of the PA root. Conclusion: The Ross procedure has excellent durability and longevity in clinical and biomechanical studies. The use of external reinforcements such as semi-resorbable scaffolds may further extend their longevity.
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Oeser C, Uyanik-Uenal K, Kocher A, Laufer G, Andreas M. The Ross procedure in adult patients: a single-Centre analysis of long-term results up to 28 years. Eur J Cardiothorac Surg 2022; 62:6631263. [PMID: 35789266 DOI: 10.1093/ejcts/ezac379] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 05/26/2022] [Accepted: 07/01/2022] [Indexed: 11/14/2022] Open
Abstract
OBJECTIVES This study aimed to provide an in-depth insight into our single-centre experience with the Ross procedure. METHODS All adults who underwent the Ross procedure between 1991 and 2014 were included. Based on the total number of Ross procedures performed by each surgeon at our centre during this 24-year period, surgeon volume was classified as low (<25 procedures), intermediate (25-44 procedures), and high (≥45 procedures). Survival, complications and reinterventions were evaluated. A single cardiologist assessed the pulmonary autograft's function and the neoaortic root diameter by echocardiography. RESULTS The outcomes of 224 patients [176 men, 48 women; mean age 37.2 (standard deviation 10.0) years] were analysed. Patients operated on by a low-volume surgeon had 7.22 times higher odds (P < 0.001) for a serious adverse event during the intraoperative or early postoperative course than patients operated on by a high-volume surgeon. Early mortality was 1.8%. Overall survival was 87.3% at 20 years. Compared with the demographically matched general population, the patients' survival was significantly lower (P = 0.002). The cumulative incidence of autograft and right ventricular outflow tract conduit reintervention was 21.5% and 5.9% at 20 years, respectively. Patients with preoperative aortic regurgitation had 6.25 times the subdistribution hazard of autograft reintervention (Bonferroni-adjusted P = 0.042) and a higher neoaortic root z-score [1.37 (standard deviation 2.04) versus 0.17 (standard deviation 1.81), P = 0.004] than patients with aortic stenosis. In patients with preoperative aortic regurgitation, autograft wrapping (remnant aortic wall and/or Vicryl® mesh) was associated with a 74% reduction in the subdistribution hazard of autograft reintervention (Bonferroni-adjusted P = 0.002) and with a reduced incidence of neoaortic root dilatation (P = 0.037). CONCLUSIONS The Ross procedure performed by a specialized surgeon provides very satisfying long-term results. The higher risk of autograft reintervention in preoperative aortic regurgitation may be counteracted by supporting the autograft.
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Affiliation(s)
- Claudia Oeser
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | | | - Alfred Kocher
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Guenther Laufer
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Martin Andreas
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
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Van Hoof L, Verbrugghe P, Jones EAV, Humphrey JD, Janssens S, Famaey N, Rega F. Understanding Pulmonary Autograft Remodeling After the Ross Procedure: Stick to the Facts. Front Cardiovasc Med 2022; 9:829120. [PMID: 35224059 PMCID: PMC8865563 DOI: 10.3389/fcvm.2022.829120] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2021] [Accepted: 01/17/2022] [Indexed: 12/12/2022] Open
Abstract
The Ross, or pulmonary autograft, procedure presents a fascinating mechanobiological scenario. Due to the common embryological origin of the aortic and pulmonary root, the conotruncus, several authors have hypothesized that a pulmonary autograft has the innate potential to remodel into an aortic phenotype once exposed to systemic conditions. Most of our understanding of pulmonary autograft mechanobiology stems from the remodeling observed in the arterial wall, rather than the valve, simply because there have been many opportunities to study the walls of dilated autografts explanted at reoperation. While previous histological studies provided important clues on autograft adaptation, a comprehensive understanding of its determinants and underlying mechanisms is needed so that the Ross procedure can become a widely accepted aortic valve substitute in select patients. It is clear that protecting the autograft during the early adaptation phase is crucial to avoid initiating a sequence of pathological remodeling. External support in the freestanding Ross procedure should aim to prevent dilatation while simultaneously promoting remodeling, rather than preventing dilatation at the cost of vascular atrophy. To define the optimal mechanical properties and geometry for external support, the ideal conditions for autograft remodeling and the timeline of mechanical adaptation must be determined. We aimed to rigorously review pulmonary autograft remodeling after the Ross procedure. Starting from the developmental, microstructural and biomechanical differences between the pulmonary artery and aorta, we review autograft mechanobiology in relation to distinct clinical failure mechanisms while aiming to identify unmet clinical needs, gaps in current knowledge and areas for further research. By correlating clinical and experimental observations of autograft remodeling with established principles in cardiovascular mechanobiology, we aim to present an up-to-date overview of all factors involved in extracellular matrix remodeling, their interactions and potential underlying molecular mechanisms.
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Affiliation(s)
- Lucas Van Hoof
- Department of Cardiac Surgery, University Hospitals Leuven, Leuven, Belgium
| | - Peter Verbrugghe
- Department of Cardiac Surgery, University Hospitals Leuven, Leuven, Belgium
| | | | - Jay D. Humphrey
- Department of Biomedical Engineering, Yale University, New Haven, CT, United States
| | - Stefan Janssens
- Department of Cardiology, University Hospitals Leuven, Leuven, Belgium
| | - Nele Famaey
- Biomechanics Section, KU Leuven, Leuven, Belgium
| | - Filip Rega
- Department of Cardiac Surgery, University Hospitals Leuven, Leuven, Belgium
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Nappi F, Iervolino A, Avtaar Singh SS. The effectiveness and safety of pulmonary autograft as living tissue in Ross procedure: a systematic review. Transl Pediatr 2022; 11:280-297. [PMID: 35282027 PMCID: PMC8905099 DOI: 10.21037/tp-21-351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 01/14/2022] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND Reports on effectiveness and safety after the implant of pulmonary autograft (PA) living tissue in Ross procedure, to treat both congenital and acquired disease of the aortic valve and left ventricular outflow tract (LVOT), show variable durability results. We undertake a quantitative systematic review of evidence on outcome after the Ross procedure with the aim to improve insight into outcome and potential determinants. METHODS A systematic search of reports published from October 1979 to January 2021 was conducted (PubMed, Ovid Medline, Ovid Embase and Cochrane library) reporting outcomes after the Ross procedure in patients with diseased aortic valve with or without LVOT. Inclusion criteria were observational studies reporting on mortality and/or morbidity after autograft aortic valve or root replacement, completeness of follow-up >90%, and study size n≥30. Forty articles meeting the inclusion criteria were allocated to two categories: pediatric patient series and young adult patient series. Results were tabulated for a clearer presentation. RESULTS A total of 342 studies were evaluated of which forty studies were included in the final analysis as per the eligibility criteria. A total of 8,468 patients were included (7,796 in pediatric cohort and young adult series and 672 in pediatric series). Late mortality rates were remarkably low alongside similar age-matched mortality with the general population in young adults. There were differences in implantation techniques as regard the variability in stress and the somatic growth that recorded conflicting outcomes regarding the miniroot vs the subcoronary approach. DISCUSSION The adaptability of lung autograft to allow for both stress variability and somatic growth make it an ideal conduit for Ross's operation. The use of the miniroot technique over subcoronary implantation for better adaptability to withstand varying degrees of stress is perhaps more applicable to different patient subgroups.
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Affiliation(s)
- Francesco Nappi
- Department of Cardiac Surgery, Centre Cardiologique du Nord, 93200 Saint-Denis, France
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8
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Wall stresses of early remodeled pulmonary autografts. J Thorac Cardiovasc Surg 2021; 164:1728-1738.e2. [PMID: 34538420 DOI: 10.1016/j.jtcvs.2021.08.058] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 08/12/2021] [Accepted: 08/23/2021] [Indexed: 11/20/2022]
Abstract
OBJECTIVE The Ross procedure is an excellent option for children or young adults who need aortic valve replacement because it can restore survival to that of the normal aged-matched population. However, autograft remodeling can lead to aneurysmal formation and reoperation, and the biomechanics of this process is unknown. This study investigated postoperative autograft remodeling after the Ross procedure by examining patient-specific autograft wall stresses. METHODS Patients who have undergone the Ross procedure who had intraoperative pulmonary root and aortic specimens collected were recruited. Patient-specific models (n = 16) were developed using patient-specific material property and their corresponding geometry from cine magnetic resonance imaging at 1-year follow-up. Autograft ± Dacron for aneurysm repair and ascending aortic geometries were reconstructed to develop patient-specific finite element models, which incorporated material properties and wall thickness experimentally measured from biaxial stretching. A multiplicative approach was used to account for prestress geometry from in vivo magnetic resonance imaging. Pressure loading to systemic pressure (120/80) was performed using LS-DYNA software (LSTC Inc, Livermore, Calif). RESULTS At systole, first principal stresses were 809 kPa (25%-75% interquartile range, 691-1219 kPa), 567 kPa (485-675 kPa), 637 kPa (555-755 kPa), and 382 kPa (334-413 kPa) at the autograft sinotubular junction, sinuses, annulus, and ascending aorta, respectively. Second principal stresses were 360 kPa (310-426 kPa), 355 kPa (320-394 kPa), 272 kPa (252-319 kPa), and 184 kPa (147-222 kPa) at the autograft sinotubular junction, sinuses, annulus, and ascending aorta, respectively. Mean autograft diameters were 29.9 ± 2.7 mm, 38.3 ± 5.3 mm, and 26.6 ± 4.0 mm at the sinotubular junction, sinuses, and annulus, respectively. CONCLUSIONS Peak first principal stresses were mainly located at the sinotubular junction, particularly when Dacron reinforcement was used. Patient-specific simulations lay the foundation for predicting autograft dilatation in the future after understanding biomechanical behavior during long-term follow-up.
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von Stumm M, Sequeira-Gross T, Petersen J, Naito S, Müller L, Sinning C, Girdauskas E. Narrative review of the contemporary surgical treatment of unicuspid aortic valve disease. Cardiovasc Diagn Ther 2021; 11:503-517. [PMID: 33968629 DOI: 10.21037/cdt-20-814] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Unicuspid aortic valve disease (UAVD) is a frequent and long-lasting challenge for adult congenital heart disease centers. UAVD patients become usually symptomatic in their twenties or thirties and require a surgical treatment plan which should respect their complete lifespan combined with an adequate quality of life. Unfortunately, all current surgical strategies of congenital aortic valve disease bear some important limitations: (I) Aortic valve replacement using bioprosthetic valves is associated with early structural degeneration and leads frequently to re-operations. (II) Mechanical valves are commonly associated with lifelong risk of severe bleeding due to oral anticoagulation. (III) Using a pulmonary autograft (i.e., Ross procedure) for aortic valve replacement is associated with excellent long-term results in non-elderly patients. However, failure of pulmonary autograft or pulmonary homograft may require re-operations. (IV) Aortic valve repair or Ozaki procedure is only performed in a few heart centers worldwide and is associated with a limited reproducibility and early patch degeneration, suture dehiscence or increased risk of endocarditis. In contrast to degenerative tricuspid aortic valve disease, UAVD remains relatively understudied and reports on UAVD treatment are rare and usually limited to retrospective single-center observations. For this review, we searched PubMed for papers in the English language by using the search words unicuspid aortic valve, congenital aortic valve, Ross procedure, Ozaki procedure, aortic valve repair, mechanical/bioprosthetic aortic replacement, homograft. We read the abstracts of relevant titles to confirm their relevance, and the full papers were then extracted. References from extracted papers were checked for additional relevant reports. This review summarizes current surgical treatment strategies for UAVD including aortic valve replacement using bioprosthetic or mechanical valves, homografts, pulmonary autografts (i.e., Ross procedure) and aortic valve repair techniques for UAV. Furthermore, Ozaki procedure will be discussed.
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Affiliation(s)
- Maria von Stumm
- Department of Cardiovascular Surgery, University Heart & Vascular Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Tatjana Sequeira-Gross
- Department of Cardiovascular Surgery, University Heart & Vascular Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Johannes Petersen
- Department of Cardiovascular Surgery, University Heart & Vascular Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Shiho Naito
- Department of Cardiovascular Surgery, University Heart & Vascular Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Lisa Müller
- Department of Cardiovascular Surgery, University Heart & Vascular Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Christoph Sinning
- Department of Cardiology, University Heart & Vascular Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Evaldas Girdauskas
- Department of Cardiovascular Surgery, University Heart & Vascular Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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Nappi F, Nenna A, Lemmo F, Chello M, Chachques JC, Acar C, Larobina D. Finite Element Analysis Investigate Pulmonary Autograft Root and Leaflet Stresses to Understand Late Durability of Ross Operation. Biomimetics (Basel) 2020; 5:biomimetics5030037. [PMID: 32756408 PMCID: PMC7559879 DOI: 10.3390/biomimetics5030037] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Revised: 07/22/2020] [Accepted: 08/01/2020] [Indexed: 01/23/2023] Open
Abstract
Ross operation might be a valid option for congenital and acquired left ventricular outflow tract disease in selected cases. As the pulmonary autograft is a living substitute for the aortic root that bioinspired the Ross operation, we have created an experimental animal model in which the vital capacity of the pulmonary autograft (PA) has been studied during physiological growth. The present study aims to determine any increased stresses in PA root and leaflet compared to the similar components of the native aorta. An animal model and a mathematical analysis using finite element analysis have been used for the purpose of this manuscript. The results of this study advance our understanding of the relative benefits of pulmonary autograft for the management of severe aortic valve disease. However, it launches a warning about the importance of the choice of the length of the conduits as mechanical deformation, and, therefore, potential failure, increases with the length of the segment subjected to stress. Understanding PA root and leaflet stresses is the first step toward understanding PA durability and the regions prone to dilatation, ultimately to refine the best implant technique.
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Affiliation(s)
- Francesco Nappi
- Department of Cardiac Surgery, Centre Cardiologique du Nord de Saint-Denis, 93200 Paris, France
- Correspondence:
| | - Antonio Nenna
- Department of Cardiovascular Surgery, University Campus Bio-Medico of Rome, 00128 Rome, Italy; (A.N.); (M.C.)
| | - Francesca Lemmo
- Faculty of Engineering, University of Turin, 10124 Turin, Italy;
| | - Massimo Chello
- Department of Cardiovascular Surgery, University Campus Bio-Medico of Rome, 00128 Rome, Italy; (A.N.); (M.C.)
| | - Juan Carlos Chachques
- Department of Cardiovascular Surgery Carpentier Foundation, Pompidou Hospital, University Paris Descartes, 75015 Paris, France;
| | - Christophe Acar
- Department of Cardiovascular Surgery, Hopital de la Salpetriere, 75013 Paris, France;
| | - Domenico Larobina
- Institute for Polymers, Composites, and Biomaterials, National Research Council of Italy, 00185 Rome, Italy;
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Mechano-biological adaptation of the pulmonary artery exposed to systemic conditions. Sci Rep 2020; 10:2724. [PMID: 32066803 PMCID: PMC7026065 DOI: 10.1038/s41598-020-59554-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Accepted: 01/29/2020] [Indexed: 12/30/2022] Open
Abstract
Cardiac surgeries may expose pulmonary arterial tissue to systemic conditions, potentially resulting in failure of that tissue. Our goal was to quantitatively assess pulmonary artery adaptation due to changes in mechanical environment. In 17 sheep, we placed a pulmonary autograft in aortic position, with or without macroporous mesh reinforcement. It was exposed to systemic conditions for 6 months. All sheep underwent 3 ECG-gated MRI’s. Explanted tissue was subjected to mechanical and histological analysis. Results showed progressive dilatation of the unreinforced autograft, while reinforced autografts stabilized after two months. Some unreinforced pulmonary autograft samples displayed more aorta-like mechanical behavior with increased collagen deposition. The mechanical behavior of reinforced autografts was dominated by the mesh. The decrease in media thickness and loss of vascular smooth muscle cells was more pronounced in reinforced than in unreinforced autografts. In conclusion, altering the mechanical environment of a pulmonary artery causes changes in its mechano-biological properties.
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Von Stumm M, Petersen J, Westermann D, Reichenspurner H, Girdauskas E. Treatment strategies for mixed aortic valve disease in nonelderly patients. Expert Rev Cardiovasc Ther 2019; 17:873-882. [DOI: 10.1080/14779072.2019.1702520] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Maria Von Stumm
- Department of Cardiovascular Surgery, University Heart Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - J. Petersen
- Department of Cardiovascular Surgery, University Heart Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - D. Westermann
- Department of Cardiology, University Heart Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Hermann Reichenspurner
- Department of Cardiovascular Surgery, University Heart Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Evaldas Girdauskas
- Department of Cardiovascular Surgery, University Heart Center, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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Nappi F, Singh SSA. Gene therapy and regenerative tissue engineering in congenital heart disease. Transl Pediatr 2019; 8:356-359. [PMID: 31993346 PMCID: PMC6970115 DOI: 10.21037/tp.2019.04.10] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Affiliation(s)
- Francesco Nappi
- Cardiac Surgery, Centre Cardiologique du Nord de Saint-Denis (CCN), Paris, France
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Nappi F, Nenna A, Larobina D, Carotenuto AR, Jarraya M, Spadaccio C, Fraldi M, Chello M, Acar C, Carrel T. Simulating the ideal geometrical and biomechanical parameters of the pulmonary autograft to prevent failure in the Ross operation. Interact Cardiovasc Thorac Surg 2019. [PMID: 29538653 DOI: 10.1093/icvts/ivy070] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES Reinforcements for the pulmonary autograft (PA) in the Ross operation have been introduced to avoid the drawback of conduit expansion and failure. With the aid of an in silico simulation, the biomechanical boundaries applied to a healthy PA during the operation were studied to tailor the best implant technique to prevent reoperation. METHODS Follow-up echocardiograms of 66 Ross procedures were reviewed. Changes in the dimensions and geometry of reinforced and non-reinforced PAs were evaluated. Miniroot and subcoronary implantation techniques were used in this series. Mechanical stress tests were performed on 36 human pulmonary and aortic roots explanted from donor hearts. Finite element analysis was applied to obtain high-fidelity simulation under static and dynamic conditions of the biomechanical properties and applied stresses on the PA root and leaflet and the similar components of the native aorta. RESULTS The non-reinforced group showed increases in the percentages of the mean diameter that were significantly higher than those in the reinforced group at the level of the Valsalva sinuses (3.9%) and the annulus (12.1%). The mechanical simulation confirmed geometrical and dimensional changes detected by clinical imaging and demonstrated the non-linear biomechanical behaviour of the PA anastomosed to the aorta, a stiffer behaviour of the aortic root in relation to the PA and similar qualitative and quantitative behaviours of leaflets of the 2 tissues. The annulus was the most significant constraint to dilation and affected the distribution of stress and strain within the entire complex, with particular strain on the sutured regions. The PA was able to evenly absorb mechanical stresses but was less adaptable to circumferential stresses, potentially explaining its known dilatation tendency over time. CONCLUSIONS The absence of reinforcement leads to a more marked increase in the diameter of the PA. Preservation of the native geometry of the PA root is crucial; the miniroot technique with external reinforcement is the most suitable strategy in this context.
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Affiliation(s)
- Francesco Nappi
- Department of Cardiac Surgery, Centre Cardiologique du Nord de Saint-Denis, Paris, France
| | - Antonio Nenna
- Department of Cardiovascular Surgery, University Campus Bio-Medico of Rome, Rome, Italy
| | - Domenico Larobina
- Institute for Polymers, Composites and Biomaterials, National Research Council of Italy, Rome, Italy
| | - Angelo Rosario Carotenuto
- Department of Structures for Engineering and Architecture and Interdisciplinary Research Center for Biomaterials, Università di Napoli 'Federico II', Naples, Italy
| | | | - Cristiano Spadaccio
- Department of Cardiothoracic Surgery, Golden Jubilee National Hospital, Glasgow, UK.,Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, UK
| | - Massimiliano Fraldi
- Department of Structures for Engineering and Architecture and Interdisciplinary Research Center for Biomaterials, Università di Napoli 'Federico II', Naples, Italy
| | - Massimo Chello
- Department of Cardiovascular Surgery, University Campus Bio-Medico of Rome, Rome, Italy
| | - Christophe Acar
- Banc de Tissus Humains Hopital Saint Louis, Paris, France.,Department of Cardiac Surgery, Hopital La Pitie Salpetriere, Paris, France
| | - Thierry Carrel
- Deptartment of cardiovascular surgery, University Hospital of Bern, Bern, Switzerland
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Ando Y, Ochiai Y, Tokunaga S, Hisahara M, Baba H, Miyagi C, Takigawa T. Size and Stiffness of the Pulmonary Autograft after the Ross Procedure in Children. Pediatr Cardiol 2019; 40:776-783. [PMID: 30734094 DOI: 10.1007/s00246-019-02064-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 01/29/2019] [Indexed: 11/24/2022]
Abstract
Progressive dilatation of the pulmonary autograft is one of the greatest concerns after the Ross procedure. Increased stress in the arterial wall may cause changes in the elastic properties of the pulmonary autograft, and thus lead to pathological dilatation. The present study aimed to investigate the changes in the autograft diameter and stiffness during follow-up after the Ross procedure. A total of ten patients underwent the Ross procedure at our institution between 2003 and 2011. Echocardiography was used to measure the diameters of the pulmonary autograft at the level of the annulus, sinus of Valsalva, and sinotubular junction. The stiffness index was calculated from the angiographic data, and compared with that of 16 age-matched control children. The diameters of the pulmonary autograft increased throughout the follow-up period, particularly at the level of the sinus of Valsalva and at the sinotubular junction. The aortic root was stiffer in Ross patients compared with control children (7.9 ± 1.8 vs. 3.9 ± 0.7 immediately postoperatively, p < 0.01; 10.1 ± 2.8 vs. 4.2 ± 1.4 at 5 years postoperatively, p < 0.01). Although no significant relationship was found between the stiffness index and the autograft diameter, the stiffness index tended to increase over time. Dilatation of the pulmonary autograft was accompanied by progressive change in aortic stiffness. Longer follow-up is warranted to clarify the impact of this change in aortic stiffness on autograft failure.
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Affiliation(s)
- Yusuke Ando
- Department of Cardiovascular Surgery, Japan Community Health Care Organization Kyushu Hospital, 1-8-1 Kishinoura, Yahatanishi-ku, Kitakyushu, 806-8501, Japan.
| | - Yoshie Ochiai
- Department of Cardiovascular Surgery, Japan Community Health Care Organization Kyushu Hospital, 1-8-1 Kishinoura, Yahatanishi-ku, Kitakyushu, 806-8501, Japan
| | - Shigehiko Tokunaga
- Department of Cardiovascular Surgery, Japan Community Health Care Organization Kyushu Hospital, 1-8-1 Kishinoura, Yahatanishi-ku, Kitakyushu, 806-8501, Japan
| | - Manabu Hisahara
- Department of Cardiovascular Surgery, Japan Community Health Care Organization Kyushu Hospital, 1-8-1 Kishinoura, Yahatanishi-ku, Kitakyushu, 806-8501, Japan
| | - Hironori Baba
- Department of Cardiovascular Surgery, Japan Community Health Care Organization Kyushu Hospital, 1-8-1 Kishinoura, Yahatanishi-ku, Kitakyushu, 806-8501, Japan
| | - Chihiro Miyagi
- Department of Cardiovascular Surgery, Japan Community Health Care Organization Kyushu Hospital, 1-8-1 Kishinoura, Yahatanishi-ku, Kitakyushu, 806-8501, Japan
| | - Tomoya Takigawa
- Department of Cardiovascular Surgery, Japan Community Health Care Organization Kyushu Hospital, 1-8-1 Kishinoura, Yahatanishi-ku, Kitakyushu, 806-8501, Japan
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Wilczek P, Paulina G, Karolina J, Martyna M, Grazyna W, Roman M, Aldona M, Anna S, Aneta S. Biomechanical and morphological stability of acellular scaffolds for tissue-engineered heart valves depends on different storage conditions. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2018; 29:106. [PMID: 29971508 PMCID: PMC6028870 DOI: 10.1007/s10856-018-6106-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 06/14/2018] [Indexed: 06/08/2023]
Abstract
Currently available bioprosthetic heart valves have been successfully used clinically; however, they have several limitations. Alternatively, tissue-engineering techniques can be used. However, there are limited data concerning the impact of storage conditions of scaffolds on their biomechanics and morphology. The aim of this study was to determine the effect of different storage conditions on the biomechanics and morphology of pulmonary valve dedicated for the acellular scaffold preparation to achieve optimal conditions to obtain stable heart valve prostheses. Scaffold can then be used for the construction of tissue-engineered heart valve, for this reason evaluation of these parameters can determine the success of the clinical application this type of bioprosthesis. Pulmonary heart valves were collected from adult porcines. Materials were divided into five groups depending on the storage conditions. Biomechanical tests were performed, both the static tensile test, and examination of viscoelastic properties. Extracellular matrix morphology was evaluated using transmission electron microscopy and immunohistochemistry. Tissue stored at 4 °C exhibited a higher modulus of elasticity than the control (native) and fresh acellular, which indicated the stiffening of the tissue and changes of the viscoelastic properties. Such changes were not observed in the radial direction. Percent strain was not significantly different in the study groups. The storage conditions affected the acellularization efficiency and tissue morphology. To the best of our knowledge, this study is the first that attributes the mechanical properties of pulmonary valve tissue to the biomechanical changes in the collagen network due to different storage conditions. Storage conditions of scaffolds for tissue-engineered heart valves may have a significant impact on the haemodynamic and clinical effects of the used bioprostheses.
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Affiliation(s)
- Piotr Wilczek
- Heart Prosthesis Institute, Bioengineering Laboratory, Wolnosci 345A, 41-800, Zabrze, Poland.
| | - Gach Paulina
- Heart Prosthesis Institute, Bioengineering Laboratory, Wolnosci 345A, 41-800, Zabrze, Poland
| | - Jendryczko Karolina
- Heart Prosthesis Institute, Bioengineering Laboratory, Wolnosci 345A, 41-800, Zabrze, Poland
| | - Marcisz Martyna
- Heart Prosthesis Institute, Bioengineering Laboratory, Wolnosci 345A, 41-800, Zabrze, Poland
| | - Wilczek Grazyna
- Department of Animal Physiology and Ecotoxicology, Faculty of Biology and Environmental Protection, University of Silesia, Bankowa 9, 40-007, Katowice, Poland
| | - Major Roman
- Institute of Metallurgy and Materials Science, Reymonta 24, 30-059, Krakow, Poland
| | - Mzyk Aldona
- Institute of Metallurgy and Materials Science, Reymonta 24, 30-059, Krakow, Poland
| | - Sypien Anna
- Institute of Metallurgy and Materials Science, Reymonta 24, 30-059, Krakow, Poland
| | - Samotus Aneta
- Heart Prosthesis Institute, Bioengineering Laboratory, Wolnosci 345A, 41-800, Zabrze, Poland
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Best to Clarify to Avoid Misunderstandings in the Biomechanics of Ross Operation: Parentheses Matter. Ann Thorac Surg 2018; 106:641-642. [PMID: 29477565 DOI: 10.1016/j.athoracsur.2018.01.047] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Accepted: 01/14/2018] [Indexed: 11/22/2022]
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Biomechanical evaluation of a personalized external aortic root support applied in the Ross procedure. J Mech Behav Biomed Mater 2017; 78:164-174. [PMID: 29156355 DOI: 10.1016/j.jmbbm.2017.11.018] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Revised: 11/07/2017] [Accepted: 11/09/2017] [Indexed: 02/07/2023]
Abstract
A commonly heard concern in the Ross procedure, where a diseased aortic valve is replaced by the patient's own pulmonary valve, is the possibility of pulmonary autograft dilatation. We performed a biomechanical investigation of the use of a personalized external aortic root support or exostent as a possibility for supporting the autograft. In ten sheep a short length of pulmonary artery was interposed in the descending aorta, serving as a simplified version of the Ross procedure. In seven of these cases, the autograft was supported by an external mesh or so-called exostent. Three sheep served as control, of which one was excluded from the mechanical testing. The sheep were sacrificed six months after the procedure. Samples of the relevant tissues were obtained for subsequent mechanical testing: normal aorta, normal pulmonary artery, aorta with exostent, pulmonary artery with exostent, and pulmonary artery in aortic position for six months. After mechanical testing, the material parameters of the Gasser-Ogden-Holzapfel model were determined for the different tissue types. Stress-strain curves of the different tissue types show significantly different mechanical behavior. At baseline, stress-strain curves of the pulmonary artery are lower than aortic stress-strain curves, but at the strain levels at which the collagen fibers are recruited, the pulmonary artery behaves stiffer than the aorta. After being in aortic position for six months, the pulmonary artery tends towards aorta-like behavior, indicating that growth and remodeling processes have taken place. When adding an exostent around the pulmonary autograft, the mechanical behavior of the composite artery (exostent + artery) differs from the artery alone, the non-linearity being more evident in the former.
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Mookhoek A, Krishnan K, Chitsaz S, Kuang H, Ge L, Schoof PH, Bogers AJ, Takkenberg JJ, Tseng EE. Biomechanics of Failed Pulmonary Autografts Compared to Native Aortic Roots. Ann Thorac Surg 2017; 103:1482-1488. [DOI: 10.1016/j.athoracsur.2016.08.061] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2015] [Revised: 08/08/2016] [Accepted: 08/15/2016] [Indexed: 11/29/2022]
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Abstract
The Ross operation provides several advantages compared to other valve substitutes to manage aortic valve disease, such as growth potential, excellent hemodynamics, freedom from oral anticoagulation and hemolysis, and better durability. However, progressive dilatation of the pulmonary autografts after Ross operation reflects the inadequate remodeling of the native pulmonary root in the systemic circulation, which results in impaired adaptability to systemic pressure and risk of reoperation after the first decade. A recently published article showed that remodeling increased wall thickness and decreased stiffness in the failed specimens after Ross operation, and the increased compliance might play a key role in determining the progressive long-term autograft root dilatation. Late dilatation can be counteracted by an external barrier which prevents failure. Therefore, an inclusion cylinder technique with a native aorta or a synthetic external support, such as Dacron, might stabilize the autograft root and improve long-term outcomes. In this article, we offer a prospective about the importance of biomechanical features in future developments of the Ross operation. Pre-clinical and clinical evaluations of the biomechanical properties of these reinforced pulmonary autografts might shed new light on the current debate about the long-term fate of the pulmonary autograft after Ross procedure.
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Affiliation(s)
- Francesco Nappi
- Department of Cardiac Surgery, Centre Cardiologique du Nord de Saint-Denis, Paris, France
| | - Antonio Nenna
- Department of Cardiovascular Surgery, Università Campus Bio-Medico di Roma, Rome, Italy
| | - Cristiano Spadaccio
- Department of Cardiothoracic Surgery, Golden Jubilee National Hospital, Glasgow, UK
| | - Massimo Chello
- Department of Cardiovascular Surgery, Università Campus Bio-Medico di Roma, Rome, Italy
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