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1.
Catheter Cardiovasc Interv ; 96(5): E542-E551, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32100937

RESUMO

OBJECTIVE: The aim of our study was to evaluate the outcome of patients with severe aortic stenosis presenting with acute decompensated heart failure (ADHF) and planned for transcatheter aortic valve implantation (TAVI) and to study the variables influencing their prognosis. METHODS: Our retrospective study included 801 patients planned for TAVI in our center. Seven hundred and fifty-six underwent TAVI and were categorized according to ADHF as the initial clinical presentation into two groups: ADHF group (n = 261) and no-ADHF group (n = 495). Pre as well as periprocedural outcomes and 1 year mortality were analyzed. RESULTS: Among the patients planned for the TAVI procedure, 45 patients remained untreated: 35 patients died while waiting to undergo TAVI which represented 20% of all deaths in our study, ADHF was observed in 23 of 45 (51%) these untreated patients. The 1-year all-cause mortality rate was significantly higher in the ADHF group versus the no-ADHF group (27% vs. 15%, p < .0001). In multivariate analysis, male gender (odds ratio [OR] =2.5, 95% confidence interval [CI]: 1.37-4.57, p = .03), body mass index <25 kg/m2 (OR = 2.76, 95% CI: 1.51-5.04, p = .0009), and logistic EuroSCORE II ≥20% (OR = 3.04, 95% CI: 1.56-5.94, p = .001) were associated with a higher 1-year mortality in the ADHF group. CONCLUSION: The patients eligible for TAVI presenting with ADHF were associated with a higher mortality for both: while on the waiting list for TAVI as well as at 1-year follow-up and thus asking for clearer criteria to prioritize action in this high-risk TAVI patients.


Assuntos
Estenose da Valva Aórtica/cirurgia , Insuficiência Cardíaca/fisiopatologia , Substituição da Valva Aórtica Transcateter , Idoso , Idoso de 80 Anos ou mais , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/mortalidade , Estenose da Valva Aórtica/fisiopatologia , Feminino , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/mortalidade , Humanos , Masculino , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Substituição da Valva Aórtica Transcateter/efeitos adversos , Substituição da Valva Aórtica Transcateter/mortalidade , Resultado do Tratamento , Listas de Espera
2.
Cell Physiol Biochem ; 44(3): 1064-1077, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29179177

RESUMO

BACKGROUND: The mismatch between traditional in vitro cell culture conditions and targeted chronic hypoxic myocardial tissue could potentially hamper the therapeutic effects of implanted bone marrow mesenchymal stem cells (BMSCs). This study sought to address (i) the extent of change to BMSC biological characteristics in different in vitro culture conditions and (ii) the effectiveness of permanent hypoxic culture for cell therapy in treating chronic myocardial infarction (MI) in rats. METHODS: rat BMSCs were harvested and cultured in normoxic (21% O2, n=27) or hypoxic conditions (5% O2, n=27) until Passage 4 (P4). Cell growth tests, flow cytometry, and Bio-Plex assays were conducted to explore variations in the cell proliferation, phenotype, and cytokine expression, respectively. In the in vivo set-up, P3-BMSCs cultured in normoxia (n=6) or hypoxia (n=6) were intramyocardially injected into rat hearts that had previously experienced 1-month-old MI. The impact of cell therapy on cardiac segmental viability and hemodynamic performance was assessed 1 month later by 2-Deoxy-2[18F]fluoro-D-glucose (18F-FDG) positron emission tomography (PET) imaging and pressure-volume catheter, respectively. Additional histomorphological examinations were conducted to evaluate inflammation, fibrosis, and neovascularization. RESULTS: Hypoxic preconditioning significantly enhanced rat BMSC clonogenic potential and proliferation without altering the multipotency. Different profiles of inflammatory, fibrotic, and angiogenic cytokine secretion were also documented, with a marked correlation observed between in vitro and in vivo proangiogenic cytokine expression and tissue neovessels. Hypoxic-preconditioned cells presented a beneficial effect on the myocardial viability of infarct segments and intrinsic contractility. CONCLUSION: Hypoxic-preconditioned BMSCs were able to benefit myocardial perfusion and contractility, probably by modulating the inflammation and promoting angiogenesis.


Assuntos
Hipóxia Celular , Transplante de Células-Tronco Mesenquimais , Infarto do Miocárdio/terapia , Animais , Células da Medula Óssea/citologia , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Citocinas/metabolismo , Fluordesoxiglucose F18/química , Coração/diagnóstico por imagem , Hemodinâmica , Inflamação , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Infarto do Miocárdio/patologia , Miocárdio/metabolismo , Miocárdio/patologia , Neovascularização Fisiológica , Fenótipo , Tomografia por Emissão de Pósitrons , Ratos , Ratos Wistar
3.
Heart Surg Forum ; 17(5): E242-4, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25367234

RESUMO

BACKGROUND: Transcatheter aortic valve implantation (TAVI) technique is now widely accepted as an alternative for the treatment of very high-risk patients in cases of aortic stenosis. However, use of this technique in cases of pure native aortic regurgitation (AR) remains discussed. CASE REPORT: We report the case of a 68-year-old patient with severe AR referred to our hospital 10 years after a supracoronary ascending aorta replacement surgery for acute type A aortic dissection. Because of respiratory contraindication to redo sternotomy, we treated this patient with the implantation of a CoreValve prosthesis inserted via right carotid access. We discuss the TAVI strategy in the case of severe AR and the possibility to use alternative vascular access. CONCLUSION: In very high-risk patients, TAVI can be discussed and considered as an alternative treatment for severe AR, with right carotid access proven as feasible.


Assuntos
Aneurisma Aórtico/cirurgia , Dissecção Aórtica/cirurgia , Insuficiência da Valva Aórtica/cirurgia , Artérias Carótidas/diagnóstico por imagem , Ajuste de Prótese/métodos , Substituição da Valva Aórtica Transcateter/métodos , Idoso , Dissecção Aórtica/complicações , Dissecção Aórtica/diagnóstico por imagem , Aneurisma Aórtico/complicações , Aneurisma Aórtico/diagnóstico por imagem , Insuficiência da Valva Aórtica/complicações , Insuficiência da Valva Aórtica/diagnóstico por imagem , Humanos , Masculino , Radiografia , Resultado do Tratamento
4.
J Heart Valve Dis ; 22(4): 517-23, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24224414

RESUMO

BACKGROUND AND AIM OF THE STUDY: Operative risk is assessed preoperatively through the use of predictive scores. The study aim was to evaluate the validity of five different scoring systems, including the Society of Thoracic Surgeons (STS) score, additive and logistic European systems (EuroSCORE 1) for cardiac operative risk evaluation, EuroSCORE 2, and the Ambler score in octogenarian patients undergoing aortic valve replacement (AVR). METHODS: A total of 225 patients aged > or = 80 years with aortic stenosis underwent isolated AVR between January 1996 and September 2010. All five scores were evaluated with regards to their accuracy in predicting operative mortality, mortality at one year, and the capacity to identify those patients most likely to die during long-term follow up. RESULTS: The observed operative mortality rate was 7.6%. The observed/expected ratios calculated for perioperative mortality were 0.42, 0.87, 1.16 and 1.16 for the logistic EuroSCORE, Ambler score, STS score and EuroSCORE 2 cohorts, respectively. The Hosmer-Lemeshow statistical test showed that all five scores were well calibrated. The STS score was a good test for predicting operative mortality (AUC 0.81) and the EuroSCORE 2 was fair (AUC 0.72). In terms of predicting the one-year mortality rate, the STS score was ranked as fair (AUC > 0.7). It was noted that patients with a STS score > or = 75th percentile were more likely to die during the follow up period. CONCLUSION: The STS score appeared to be more adequate for predicting operative mortality among patients aged > or = 80 years. STS scores were predictive of both one-year and long-term survival rates. These results indicated that the STS score could be used to guide clinical decision-making for performing AVR in elderly patients.


Assuntos
Estenose da Valva Aórtica , Valva Aórtica/cirurgia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Complicações Pós-Operatórias , Fatores Etários , Idoso de 80 Anos ou mais , Estenose da Valva Aórtica/diagnóstico , Estenose da Valva Aórtica/cirurgia , Área Sob a Curva , Feminino , Humanos , Masculino , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/mortalidade , Complicações Pós-Operatórias/prevenção & controle , Valor Preditivo dos Testes , Período Pré-Operatório , Curva ROC , Projetos de Pesquisa , Medição de Risco/métodos , Índice de Gravidade de Doença , Análise de Sobrevida , Resultado do Tratamento
5.
JTCVS Open ; 16: 401-418, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38204662

RESUMO

Objective: The Evaluation of Transit-Time Flow in Coronary Artery Disease Surgery (EFCAD) registry aims to assess the influence of transit-time flow measurement (TTFM) in daily practice. Methods: EFCAD is a prospective, multicenter study involving 9 centers performing TTFM during isolated coronary artery bypass grafting. Primary end point was occurrence and risk factors of major adverse cardiac events, including perioperative myocardial infarction, urgent postoperative coronary angiogram and/or revascularization, and hospital mortality. Secondary end points were rate of graft revision during surgery and factors affecting graft flow. We respected the limit values set by the experts: mean graft flow >15 mL/minute and pulsatility index ≤5. Results: Between May 2017 and March 2021, 1616 patients were registered in the EFCAD database. After review, 1414 were included for analyses. Of those, 1176 were eligible for primary end point analysis. Graft revision, mainly due to inadequate TTFM values, occurred in 2% (29 patients). The primary end point occurred in 46 (3.9%) patients, and it was related with left anterior descending artery graft flow ≤15 mL/minute (odds ratio, 3.64; P < .001). Graft flow was related with number of grafts (3 vs 1-2, ß = -1.6; 4-6 vs 1-2, ß = -4.1; P < .001; ß > 0 indicates higher flow), and graft origin (aorta vs Y, ß = 9.2; in situ left internal thoracic artery vs Y, ß = 3.2; in situ right internal thoracic artery vs Y, ß = 2.3; P < .001). Conclusions: Data from EFCAD study suggest that TTFM is reliable to evaluate graft flow, and acceptance of inadequate flow on left anterior descending artery anastomosis influence postoperative outcomes. In our opinion, TTFM assessment should be routinely used in coronary artery bypass procedures, even if interpretation depends on learning curves.

6.
J Biomed Sci ; 19: 93, 2012 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-23146158

RESUMO

BACKGROUND: Tissue engineering scaffold constitutes a new strategy of myocardial repair. Here, we studied the contribution of a patch using autologous mesenchymal stem cells (MSCs) seeded on collagen-1 scaffold on the cardiac reconstruction in rat model of chronic myocardial infarction (MI). METHODS: Patches were cultured with controlled MSCs (growth, phenotype and potentiality). Twenty coronary ligated rats with tomoscingraphy (SPECT)-authenticated transmural chronic MI were referred into a control group (n = 10) and a treated group (n = 10) which beneficiated an epicardial MSC-patch engraftment. Contribution of MSC-patch was tested 1-mo after using non-invasive SPECT cardiac imaging, invasive hemodynamic assessment and immunohistochemistry. RESULTS: 3D-collagen environment affected the cell growth but not the cell phenotype and potentiality. MSC-patch integrates well the epicardial side of chronic MI scar. In treated rats, one-month SPECT data have documented an improvement of perfusion in MI segments compared to control (64 ± 4% vs 49 ± 3% p = 0.02) and a reduced infarction. Contractile parameter dp/dtmax and dp/dtmin were improved (p & 0.01). Histology showed an increase of ventricular wall thickness (1.75 ± 0.24 vs 1.35 ± 0.32 mm, p &0.05) and immunochemistry of the repaired tissue displayed enhanced angiogenesis and myofibroblast-like tissue. CONCLUSION: 3D-MSC-collagen epicardial patch engraftment contributes to reverse remodeling of chronic MI.


Assuntos
Transplante de Células-Tronco Mesenquimais , Infarto do Miocárdio , Engenharia Tecidual , Remodelação Ventricular , Animais , Células Cultivadas , Colágeno , Modelos Animais de Doenças , Ventrículos do Coração/fisiopatologia , Células-Tronco Mesenquimais/citologia , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/terapia , Neovascularização Patológica , Ratos , Transplante Autólogo
7.
J Card Surg ; 27(1): 65-9, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22321114

RESUMO

BACKGROUND AND AIM: Emergency surgery for type A aortic dissection (AAD) is associated with high mortality rates. The published outcomes of such surgery in aging patients are controversial and the optimal management for elderly patients has not been established. Our study aimed to evaluate the outcomes of surgery for AAD in patients over the age of 80 years. MATERIALS AND METHODS: Between January 1996 and January 2010, 236 patients underwent surgery for AAD, of which 15 patients were older than 80 years. We evaluated the operative mortality in the whole cohort compared to the outcomes in the elderly subgroup. We assessed the preoperative risks factors and quality of life after surgery by performance status and the patients' ability to return home. RESULTS: Operative mortality was higher in patients aged >80 years (40% vs. 18%, p = 0.04). The survival rate for patients >80 years at one, three, and five years was 53.3% ± 0.12%, 42.6% ± 0.14%, and 42.6% ± 0.12%, respectively. Of the survivors, six patients were able to return home (40%) and the postoperative performance status was "3" in one patient, "2" in six patients, and "1" in two patients. A preoperative level of 2 or greater was found to be a significant risk factor (p = 0.04). CONCLUSION: Survival in octogenarians undergoing surgery for AAD is possible, and some patients were able to return home with a reasonable level of autonomy. Larger series will be needed to define the optimal management for octogenarians presenting with AAD.


Assuntos
Ruptura Aórtica/cirurgia , Doença Aguda , Fatores Etários , Idoso de 80 Anos ou mais , Ruptura Aórtica/mortalidade , Ponte Cardiopulmonar , Feminino , Humanos , Estimativa de Kaplan-Meier , Modelos Logísticos , Masculino , Autonomia Pessoal , Complicações Pós-Operatórias , Qualidade de Vida , Estudos Retrospectivos , Fatores de Risco , Esternotomia , Taxa de Sobrevida , Resultado do Tratamento
8.
JTCVS Open ; 9: 43-56, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36003460

RESUMO

Objective: To perform an in vitro characterization of surgical aortic valves (SAVs) and transcatheter aortic valves (TAVs) to highlight the development of the flow dynamics depending on the type of valve implanted and assess the basic differences in the light of flow turbulence and its effect on blood damage likelihood and hemodynamic parameters that shed light on valve performance. Methods: A Starr-Edwards ball and cage valve of internal diameter 22 mm, a 23-mm Medtronic Hancock II SAV, a 23-mm St Jude Trifecta SAV, a 23-mm St Jude SJM (mechanical valve) SAV, a 26-mm Medtronic Evolut TAV, and a 26-mm Edwards SAPIEN 3 TAV were assessed in a pulse duplicator under physiological conditions. Particle image velocimetry was performed for each valve. Pressure gradient and effective orifice area (EOA) along with velocity flow field, Reynolds shear stress (RSS), and viscous shear stress (VSS) were calculated. Results: The SJM mechanical valve exhibited the greatest EOA (1.96 ± 0.02 cm2), showing superiority of efficiency compared with the same-size Trifecta (1.87 ± 0.07 cm2) and Hancock II (1.05 ± 0.01 cm2) (P < .0001). The TAVs show close EOAs (2.10 ± 0.06 cm2 with Evolut and 2.06 ± 0.03 cm2 with SAPIEN 3; P < .0001). The flow characteristics and behavior downstream of the valves differed depending on the valve type, design, and size. The greater the RSS and VSS the more turbulent the downstream flow. Hancock II displays the greatest range of RSS and VSS magnitudes compared with the same-size Trifecta and SJM. The Evolut displays the greatest range of RSS and VSS compared with the SAPIEN 3. Conclusions: The results of this study shed light on numerous advancements in the design of aortic valve replacement prosthesis and the subsequent hemodynamic variations. Future surgical and transcatheter valve designs should aim at not only concentrating on hemodynamic parameters but also at optimizing downstream flow properties.

9.
Chem Biol Interact ; 351: 109738, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34740598

RESUMO

The rapid spread of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) that causes coronavirus disease 2019 (COVID-19), has had a dramatic negative impact on public health and economies worldwide. Recent studies on COVID-19 complications and mortality rates suggest that there is a higher prevalence in cardiovascular diseases (CVD) patients. Past investigations on the associations between pre-existing CVDs and susceptibility to coronavirus infections including SARS-CoV and the Middle East Respiratory Syndrome coronavirus (MERS-CoV), have demonstrated similar results. However, the underlying mechanisms are poorly understood. This has impeded adequate risk stratification and treatment strategies for CVD patients with SARS-CoV-2 infections. Generally, dysregulation of the expression of angiotensin-converting enzyme (ACE) and the counter regulator, angiotensin-converting enzyme 2 (ACE2) is a hallmark of cardiovascular risk and CVD. ACE2 is the main host receptor for SARS-CoV-2. Although further studies are required, dysfunction of ACE2 after virus binding and dysregulation of the renin-angiotensin-aldosterone system (RAAS) signaling may worsen the outcomes of people affected by COVID-19 and with preexisting CVD. Here, we review the current knowledge and outline the gaps related to the relationship between CVD and COVID-19 with a focus on the RAAS. Improved understanding of the mechanisms regulating viral entry and the role of RAAS may direct future research with the potential to improve the prevention and management of COVID-19.


Assuntos
COVID-19/fisiopatologia , Doenças Cardiovasculares/fisiopatologia , Sistema Renina-Angiotensina/fisiologia , Antagonistas de Receptores de Angiotensina/uso terapêutico , Enzima de Conversão de Angiotensina 2/metabolismo , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , COVID-19/complicações , Doenças Cardiovasculares/complicações , Humanos , Receptores de Coronavírus/metabolismo , Fatores de Risco , SARS-CoV-2/efeitos dos fármacos , Tratamento Farmacológico da COVID-19
10.
J Thorac Cardiovasc Surg ; 161(2): 565-576.e2, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-31767355

RESUMO

BACKGROUND: The durability of transcatheter aortic valves (TAVs) remains their greatest disadvantage, given that fixed tissue leaflets are not immune to structural degeneration from calcification and thrombosis. Therefore, a second intervention is necessary, especially given that TAV in low-risk patients has shown noninferior outcomes compared with surgery. This study aimed to assess the hemodynamic and turbulent properties of the flow downstream with different TAV-in-TAV configurations, to offer basic hemodynamic guidance for future interventions when currently implanted valves structurally degrade. METHODS: Six TAV-in-TAV configurations were chosen: 23 mm Evolut-in-26 mm Evolut, 23 mm Evolut-in-23 mm SAPIEN 3, 26 mm Evolut-in-26 mm Evolut, 26 mm Evolut-in-23 mm SAPIEN 3, 23 mm SAPIEN3-in-26 mm Evolut, and 23 mm SAPIEN3-in-23 mm SAPIEN 3. Their hemodynamic performance was assessed in a pulse duplicator for 100 cycles. High-speed imaging and particle image velocimetry were performed to assess turbulence. Effective orifice area (EOA), pinwheeling index (PI), and Reynolds shear stress (RSS) were evaluated. RESULTS: The largest mean EOA was obtained with 23 mm SAPIEN-in-26 mm Evolut (2.07 ± 0.06 cm2), and the smallest was obtained with 23 mm Evolut-in-23 mm SAPIEN (1.50 ± 0.04 cm2) (P < .001). The highest mean PI was obtained with SAPIEN-in-SAPIEN (26.5 ± 2.00%), and the lowest was obtained with 26 mm Evolut-in-26 mm Evolut (7.5 ± 1.6%) (P < .01). At peak systole, the least detrimental RSS range was obtained with 23 mm Evolut-in-26 mm Evolut (up to ∼340 Pa), and the most detrimental RSS range was obtained with 23 mm Evolut-in-SAPIEN (∼900 Pa) (P < .01). CONCLUSIONS: This study shows that best hemodynamic parameters are TAV-specific (implanted and to be implanted). In addition, it shows that RSS levels, which are indicative of turbulence levels and associated with blood damage, are 2- to 3-fold higher after TAV-in-TAV.


Assuntos
Valva Aórtica/fisiopatologia , Próteses Valvulares Cardíacas , Hemodinâmica/fisiologia , Substituição da Valva Aórtica Transcateter , Velocidade do Fluxo Sanguíneo/fisiologia , Humanos , Falha de Prótese , Reoperação
11.
J Mech Behav Biomed Mater ; 119: 104492, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33892336

RESUMO

Biomaterials applied to the epicardium have been studied intensively in recent years for different therapeutic purposes. Their mechanical influence on the heart, however, has not been clearly identified. Most biomaterials for epicardial applications are manufactured as membranes or cardiac patches that have isotropic geometry, which is not well suited to myocardial wall motion. Myocardial wall motion during systole and diastole produces a complex force in different directions. Membrane or cardiac patches that cannot adapt to these specific directions will exert an inappropriate force on the heart, at the risk of overly restricting or dilating it. Accurately characterizing the mechanical properties of the myocardial wall is thus essential, through analysis of muscle orientation and elasticity. In this study, we investigated the Hertz contact theory for characterizing cardiac tissue, using nanoindentation measurements to distinguish different patterns in the local myocardium. We then evaluated the predictive accuracy of this model using Finite Element Analysis (FEA) to mimic the diastolic phase of the heart. Our results, extracted from instrumented nanoindentation experiments in a liquid environment using five pig hearts, revealed variations in elasticity according to the local orientation of the myocardial tissue. In addition, applying the Finite Element Method (FEM) in our model based on transverse isotropy and local tissue orientation proved able to accurately simulate the passive filling of a left ventricle (LV) in a representative 3D geometry. Our model enables improved understanding of the underlying mechanical properties of the LV wall and can serve as a guide for designing and manufacturing biomedical material better adapted to the local epicardial tissue.


Assuntos
Materiais Biocompatíveis , Ventrículos do Coração , Animais , Simulação por Computador , Modelos Cardiovasculares , Estresse Mecânico , Suínos
12.
Eur Heart J Case Rep ; 5(3): ytaa447, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33733044

RESUMO

BACKGROUND: The outbreak of coronavirus disease 2019 (COVID-19) exposes vulnerable patients to high risk of mortality. Patients with left ventricular assist device (LVAD) usually have symptoms such as cough, fever, and shortness of breath because of their cardiac condition and comorbidity, therefore these related symptoms challenge the correct diagnosis in time within the COVID-19 pandemic. CASE SUMMARY: We report two case studies of patients with LVAD in whom COVID-19 related symptoms were overlapped by their cardiac status and comorbidities. In the first case, the patient was admitted for suspicion of COVID-19 due to cough and shortness of breath for 1 month. The blood test evocated a high index of suspicion of COVID-19. The nasopharyngeal test for COVID-19 performed on admission and at Day 2 was inconclusive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), but the test obtained on Day 3 of admission was positive, whereas computed tomography confirmed the diagnosis of COVID-19. This patient developed acute respiratory distress syndrome (ARDS) and nasal epistaxis within 48 h during hospitalization. The ARDS was treated by non-invasive ventilation and probabilistic antibiotics for 3 days and resulted significant improvement. The nasal epistaxis due to international normalized ratio increase was treated by nasal packing and vitamin K antagonist was switched to parenteral heparin infusion. The patient was kept hospitalized for 1 month for further supportive treatment. In the second case, the patient was admitted for recurrent anaemia due to melaena, the patient was tested for COVID-19 because of new-onset symptoms of cough and rhinorrhoea. The first nasopharyngeal test was positive, and sudden increase of anticoagulation status was noted in the setting of gastrointestinal bleeding. The anticoagulation status was controlled by parenteral heparin infusion, and the melaena was disappeared at Day 3. The moderate dyspnoea of the patient was quickly improved with nasal oxygen delivery for 4 days. The patient was discharged at Day 5. DISCUSSION: COVID-19 specific symptoms are challenging to distinguish in patients with LVADs, although radiological evidence can be beneficial in the COVID-19 diagnosis. We also observed the need for precise anticoagulation control to avoid bleeding or thrombotic events in these patients.

13.
Biomed Pharmacother ; 138: 111425, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33756154

RESUMO

Cardiovascular disease is one of the leading causes of mortality worldwide. Cardiac tissue engineering strategies focusing on biomaterial scaffolds incorporating cells and growth factors are emerging as highly promising for cardiac repair and regeneration. The use of stem cells within cardiac microengineered tissue constructs present an inherent ability to differentiate into cell types of the human heart. Stem cells derived from various tissues including bone marrow, dental pulp, adipose tissue and umbilical cord can be used for this purpose. Approaches ranging from stem cell injections, stem cell spheroids, cell encapsulation in a suitable hydrogel, use of prefabricated scaffold and bioprinting technology are at the forefront in the field of cardiac tissue engineering. The stem cell microenvironment plays a key role in the maintenance of stemness and/or differentiation into cardiac specific lineages. This review provides a detailed overview of the recent advances in microengineering of autologous stem cell-based tissue engineering platforms for the repair of damaged cardiac tissue. A particular emphasis is given to the roles played by the extracellular matrix (ECM) in regulating the physiological response of stem cells within cardiac tissue engineering platforms.


Assuntos
Microambiente Celular/fisiologia , Cardiopatias/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Miócitos Cardíacos/transplante , Engenharia Tecidual/métodos , Transplante Autólogo/métodos , Animais , Cardiopatias/fisiopatologia , Humanos , Transplante de Células-Tronco Mesenquimais/tendências , Células-Tronco Mesenquimais/fisiologia , Miócitos Cardíacos/fisiologia , Engenharia Tecidual/tendências , Transplante Autólogo/tendências
14.
Eur J Nucl Med Mol Imaging ; 37(9): 1745-50, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20393712

RESUMO

PURPOSE: 18F-Fluorodeoxyglucose (FDG) imaging, provided by current positron emission tomography (PET) systems dedicated to small animals,might provide a precise functional assessment of the left ventricle (LV) in rats, although conventional metabolic conditioning by hyperinsulinaemic glucose clamping is not well adapted to this setting. This study was aimed at assessing cardiac FDG PET in rats premedicated with acipimox, a potent nicotinic acid derivative yielding comparable image quality to clamping in man. METHODS: Metabolic conditioning was compared in Wistar rats between a conventional oral glucose loading (1.5 mg/kg) and acipimox, which was given at high but well tolerated doses subcutaneously (25 mg/kg) or orally (50 mg/kg). Myocardial to blood (M/B) activity ratio and myocardial signal to noise (S/N) ratio were analysed on gated FDG PET images. RESULTS: The S/N ratio of the gated cardiac images evolved in parallel with the M/B activity ratio and these two ratios were independently enhanced by glucose loading and acipimox. However, these enhancements were: (1) dramatic for acipimox, especially for the high oral dose of 50 mg/kg (from 2.85 +/- 0.57 to 10.73 +/- 0.54 for the M/B ratio of rats with or without glucose loading; p<0.0001) and (2) much more limited for glucose loading (from 6.61 +/- 0.49 to 7.89 +/- 0.41 for the M/B ratio of rats with or without acipimox administration; p=0.049). With the high oral dose of acipimox, the gated cardiac FDG PET images had very high S/N ratios, at least equivalent to those currently documented in man. CONCLUSION: Metabolic conditioning by oral doses of acipimox is highly efficient for experimental studies planned with cardiac FDG PET in rats.


Assuntos
Eletrocardiografia , Fluordesoxiglucose F18 , Coração/efeitos dos fármacos , Coração/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Pirazinas/farmacologia , Animais , Técnicas de Imagem de Sincronização Cardíaca , Relação Dose-Resposta a Droga , Glucose/administração & dosagem , Glucose/farmacologia , Coração/fisiologia , Masculino , Pirazinas/administração & dosagem , Ratos , Ratos Wistar , Função Ventricular Esquerda/efeitos dos fármacos
16.
J Thorac Cardiovasc Surg ; 159(1): 88-97, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30905419

RESUMO

OBJECTIVE: The objective of this study was to investigate and compare the hemodynamic and turbulence characteristics upon implantation of St Jude Medical (SJM) (St Jude Medical, St Paul, Minn) and On-X (On-X Life Technologies, Kennesaw, Ga) bileaflet mechanical valves. Both valves are considered highly successful bileaflet mechanical valves characterized by good clinical outcomes despite their numerous design differences. Although thromboembolism remains the main disadvantage of bileaflet mechanical valves, On-X valves have been shown to need less anticoagulation therapy. METHODS: Hemodynamic assessment of a 23-mm On-X bileaflet mechanical valve and a 23-mm bileaflet SJM valve implanted in an aortic root was performed under pulsatile physiologic conditions. Time-resolved and phase-locked particle-image-velocimetry images and high-speed imaging data were acquired. Pressure gradients, effective orifice areas, dimensionless area index, leaflet position tracking, velocity, and principal Reynolds shear stress were calculated. RESULTS: Pressure gradient for the On-X valve was 4.15 ± 0.099 mm Hg versus 4.75 ± 0.048 mm Hg for SJM (P < .001). Effective orifice area for the On-X valve was 2.61 ± 0.045 cm2 versus 2.36 ± 0.022 cm2 for SJM (P < .001). Area index was higher with SJM (0.87 ± 0.008) than with On-X (0.73 ± 0.013) (P < .001). On-X showed fluctuating leaflet behavior during systole, whereas SJM leaflets were stable. At peak systole, the maximal velocity with On-X was 1.86 m/s versus 2.33 m/s with SJM. Reynolds shear stress was higher with On-X compared with SJM at peak systole (95 vs 72 Pa). Higher velocity fluctuation was noted with the On-X valve. CONCLUSIONS: This study shows that despite the design differences that characterize the On-X valve, the hemodynamic and turbulence parameters were not necessarily improved compared with SJM.

17.
Cardiovasc Revasc Med ; 21(3): 271-276, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31281093

RESUMO

BACKGROUND/PURPOSE: This study aims at evaluating the impact of BASILICA on neo-sinus and sinus hemodynamics with and without coronary flow. Leaflet thrombosis after valve-in-valve (ViV) may compromise not only leaflet mobility but also affect valve durability and performance. METHODS/MATERIALS: In a 23 mm transparent surgical aortic valve model, a 23 mm Edwards SAPIEN 3 and a 26 mm Medtronic Evolut were deployed before and after leaflet laceration, in models with and without coronary flow. Neo-sinus and sinus hemodynamics were evaluated in the aortic position of a pulse duplicator and particle image velocimetry was performed in order to quantify sinus flow hemodynamics along with sinus and neo-sinus washout. RESULTS: BASILICA-type leaflet laceration procedure led to (a) an increase in the velocities in the sinus and the neo-sinus by 50% for Evolut ViV with and without coronary flow, 70% for non-coronary SAPIEN 3 ViV and 10% for coronary SAPIEN 3 ViV, and (b) an improvement in overall washout up to 2 cycles in the neo-sinus and 0.5 cycles in the sinus. CONCLUSIONS: A BASILICA-type leaflet laceration approach may improve sinus and neo-sinus hemodynamics through decreasing flow stasis and enabling less confined blood flow. BASILICA confers coronary sinus flow patterns to the non-coronary sinus.


Assuntos
Valva Aórtica/cirurgia , Circulação Coronária , Seio Coronário/cirurgia , Implante de Prótese de Valva Cardíaca/instrumentação , Próteses Valvulares Cardíacas , Hemodinâmica , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/fisiopatologia , Velocidade do Fluxo Sanguíneo , Seio Coronário/diagnóstico por imagem , Seio Coronário/fisiopatologia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Humanos , Teste de Materiais , Desenho de Prótese , Fatores de Tempo
18.
Ann Thorac Surg ; 110(4): 1348-1356, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32179042

RESUMO

BACKGROUND: This study evaluated the effect of transcatheter aortic valve (TAV)-in-TAV on sinus hemodynamics and washout. With TAV becoming the standard procedure for aortic valve replacement and with the limited valve durability, a second intervention is necessary (TAV-in-TAV) after first TAV failure. METHODS: Six arrangements of TAV-in-TAV were chosen for this study as follows: (1) Evolut 23 (Medtronic, Minneapolis, MN) in Evolut 26, (2) Evolut 23 in SAPIEN 3 23 (Edwards Lifesciences, Irvine, CA), (3) Evolut 26 in Evolut 26, (4) Evolut 26 in SAPIEN 23, (5) SAPIEN 3 23 in Evolut 26, and (6) SAPIEN 3 23 in SAPIEN 3 23. These TAV-in-TAV configurations were assessed in a pulse duplicator. Particle image velocimetry was performed. RESULTS: During systole, (1) the highest velocity was found with SAPIEN-in-SAPIEN (0.7 m/s) and the lowest was with Evolut 26-in-Evolut 26 (0.2 m/s); (2) the highest shear stress magnitude near the leaflet was with Evolut 23-in-SAPIEN (1.45 Pa) and the lowest was with Evolut 26-in-Evolut 26 (0.55 Pa); and (3) washout was almost equal in all sinuses of these cases (<2.5 cycles). CONCLUSIONS: This study shows that TAV-in-TAV is highly dependent on the valve that is originally implanted and the valve to be implanted. Washout is not significantly degraded after TAV-in-TAV compared with valve-in-valve and TAV replacement. Further studies are needed to optimize valve size and selection.


Assuntos
Estenose da Valva Aórtica/cirurgia , Próteses Valvulares Cardíacas , Seio Aórtico/fisiopatologia , Substituição da Valva Aórtica Transcateter/instrumentação , Resistência Vascular/fisiologia , Humanos , Modelos Cardiovasculares , Desenho de Prótese , Resistência ao Cisalhamento , Estresse Mecânico
19.
J Thorac Dis ; 12(10): 5561-5570, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33209389

RESUMO

BACKGROUND: Left heart involvement might be a differential factor in the physiopathology and prognosis of severe tricuspid regurgitation (TR) following cardiac surgery. We aimed to compare the outcomes of isolated tricuspid valve surgery (ITVS) after congenital versus left heart-disease surgery. METHODS: We retrospectively studied and followed up 58 patients who underwent ITVS for TR following cardiac surgery in our center from January 2012 to December 2017. According to the different etiologies of TR, the participants were divided into one group of TR following surgery for congenital heart diseases (CHD) (pCHD group, n=24), and another group of TR following surgery for left heart disease (pVHD group, n=34). RESULTS: Compared to the pCHD group, the pVHD group presented with a more advanced age (P<0.001), higher model for end-stage liver disease (MELD) score calculation (P=0.04), and higher EuroSCORE II calculation (P=0.01). In the post-operative course, the pVHD group showed a longer mechanical ventilation time (P<0.001) and longer intensive care unit stay (P=0.001). However, there was no significant difference between the two groups in in-hospital mortality (8.8% vs. 0, P=0.26), or the incidence of major adverse cardiac and cerebrovascular events (MACCE) (20.6% vs. 12.5%, P=0.47) at follow-up. CONCLUSIONS: Severe TR following surgery for left heart disease is associated with higher surgical risks and a remarkable frailty as compared to that following surgery for CHDs; however, with the development of surgical techniques and peri-operative management, ITVS can be safely performed in both conditions with promising contemporary mid-term outcomes.

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