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1.
J Cardiovasc Dev Dis ; 10(7)2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37504546

RESUMO

Fontan patients undergo multiple cardiothoracic surgeries in childhood. Following these procedures, ventricular function is temporarily decreased, and recovers over months. This is presumably related to cardiopulmonary bypass, but this is incompletely understood. Throughout the Fontan palliation, cardiac function is also affected by volume unloading. We aimed to gain insight into the biological processes related to impaired ventricular function and recovery following Fontan palliations using a panel of biomarkers. Furthermore, we described changes in ventricular function across the Fontan palliation due to volume unloading. We performed a prospective multicenter observational study in patients undergoing partial (PCPC) or total cavo-pulmonary connection (TCPC). Patients underwent assessment-including echocardiography and blood sampling-before surgery (T1), at first follow-up (T2), and 1 year after their procedures (T3). Blood samples were analyzed using a biomarker panel (OLINK CVD-III). Ninety-two biomarkers were expressed as principal components (PC) to limit multiple statistical testing. We included 32 PCPC patients aged 7.2 [5.3-10.3] months, and 28 TCPC patients aged 2.7 [2.2-3.8] years. The single ventricular longitudinal strain (SV GLS) temporarily decreased for PCPC patients at T2 (-15.1 ± 5.6 (T1) to -13.5 ± 5.2 (T2) to -17.3 ± 4.5 (T3), p < 0.047 for all differences), but not following TCPC. The serum biomarkers were expressed as 4 PCs. PC1, including biomarkers of cell-cell adhesion, was not related to any patient characteristic. PC2, including biomarkers of superoxide anion regulation, increased at T2. PC3, including biomarkers of cardiovascular development, related to the stage of Fontan palliation. PC4 was of uncertain biological or clinical significance. No PC was found that related to ventricular performance. The SV GLS was temporarily diminished following PCPC, but not following TCPC. Several biomarkers were related to post-operative stress and adaptation to the PCPC or TCPC circulation, but none were related to the outcome.

2.
Clin Res Cardiol ; 112(10): 1417-1426, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37031447

RESUMO

BACKGROUND: Nowadays, more than 90% of patients with congenital heart disease (CHD) reach adulthood. However, long-term impact on neurodevelopment and executive functioning in adults with CHD are not completely understood. PURPOSE: To investigate the self- and informant-reported executive functioning in adults with CHD operated in childhood. MATERIAL AND METHODS: Longitudinal study of a cohort of patients (n = 194, median age: 49.9 [46.1-53.8]) who were operated in childhood (< 15 years old) between 1968 and 1980 (median follow-up time: 45 [40-53] years) for one of the following diagnoses: atrial septal defect (ASD), ventricular septal defect (VSD), pulmonary stenosis (PS), tetralogy of Fallot (ToF) or transposition of the great arteries (TGA). Behavior Rating Inventory of Executive Function-Adult version (BRIEF-A) questionnaire was used to assess self- and informant-reported executive functioning. RESULTS: 40-53 years after surgery, the CHD group did show significantly better executive functioning compared to the norm data. No significant difference was found between mild CHD (ASD, VSD and PS) and moderate/severe CHD (ToF and TGA). Higher education, NYHA class 1 and better exercise capacity were associated with better self-reported executive functioning, whereas females or patients taking psychiatric or cardiac medications reported worse executive functioning. CONCLUSIONS: Our findings suggest favorable outcomes (comparable to normative data) regarding executive functioning in adults with CHD, both self- and informant-reported. However, further study is warranted to explore more in detail the different cognitive domains of executive functioning in these patients.


Assuntos
Cardiopatias Congênitas , Comunicação Interatrial , Comunicação Interventricular , Transposição dos Grandes Vasos , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Transposição dos Grandes Vasos/complicações , Transposição dos Grandes Vasos/cirurgia , Função Executiva , Estudos Longitudinais , Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/cirurgia , Comunicação Interventricular/complicações , Comunicação Interatrial/complicações
3.
J Hosp Infect ; 132: 73-77, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36572347

RESUMO

BACKGROUND: Mycobacterium chimaera colonizes water-based heater-cooler units (HCUs), from which it can spread to patients during surgery. Vermamoeba vermiformis is a free-living waterborne amoeba, which was consistently present within HCUs. AIM: To determine whether these amoebae can be involved in the persistent presence of M. chimaera. METHODS: An in-vitro disinfection model. FINDINGS: Increased survival of M. chimaera was observed after chlorine exposure in the presence of V. vermiformis. Confocal microscopy demonstrated the intracellular presence of M. chimaera in V. vermiformis. CONCLUSION: In this way, V. vermiformis can contribute to the persistent presence of M. chimaera in HCUs. Cleaning and disinfection protocols should take this phenomenon into account.


Assuntos
Infecções por Mycobacterium , Mycobacterium , Humanos , Infecções por Mycobacterium/microbiologia , Cloro/farmacologia , Contaminação de Equipamentos
4.
World J Pediatr Congenit Heart Surg ; 12(2): 230-233, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33684007

RESUMO

BACKGROUND: During unifocalization procedures for pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries, collateral arteries are either ligated or detached. Not much is known of the fate of the remaining arterial origins in the long term. Available computed tomography (CT) or magnetic resonance (MR) imaging of the intrathoracic arteries was examined to investigate possible abnormalities at the former position of the collateral arteries as well as ascending aortic diameters. METHODS: From 1989 to 2018, we performed 66 unifocalization procedures in 39 patients. One hundred and twenty-nine collateral arteries were ligated or detached. In 52% (15) of the surviving patients (with a total of 55 ligated or detached collaterals), sufficient imaging of the thoracic aorta from CT (11) and/or MR (9) was available for evaluation. RESULTS: The median interval between unifocalization procedure and imaging was 15 years (interquartile range [IQR]: 9-19 years). In 93% (14) of the scanned patients, 18 blunt ends were detected at the location of a former collateral artery. No aneurysm formation of the descending aorta was observed. The median diameter of the ascending aorta was 35 mm (IQR: 31-40 mm). During follow-up, no aortic dissection or rupture occurred. CONCLUSIONS: Aortic imaging late after unifocalization showed abnormalities in 93% of the scanned patients. Abnormalities consisted mostly of blunt ends of the former collateral artery. We recommend to include routine imaging of the aorta during late follow-up to detect eventual future abnormalities and monitor aortic diameters. Ascending aortic diameters showed slight dilatation with no clinical implications so far.


Assuntos
Aorta Torácica/anormalidades , Procedimentos Cirúrgicos Cardíacos/métodos , Circulação Colateral/fisiologia , Cardiopatias Congênitas/cirurgia , Artéria Pulmonar/anormalidades , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/cirurgia , Pré-Escolar , Feminino , Cardiopatias Congênitas/diagnóstico , Humanos , Lactente , Ligadura , Imagem Cinética por Ressonância Magnética , Masculino , Artéria Pulmonar/diagnóstico por imagem , Artéria Pulmonar/cirurgia
5.
J Headache Pain ; 20(1): 47, 2019 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-31053059

RESUMO

BACKGROUND: Racemic isometheptene [(RS)-isometheptene] is an antimigraine drug that due to its cardiovascular side-effects was separated into its enantiomers, (R)- and (S)-isometheptene. This study set out to characterize the contribution of each enantiomer to its vasoactive profile. Moreover, rat neurogenic dural vasodilatation was used to explore their antimigraine mechanism of action. METHODS: Human blood vessel segments (middle meningeal artery, proximal and distal coronary arteries, and saphenous vein) were mounted in organ baths and concentration response curves to isometheptene were constructed. Calcitonin gene-related peptide (CGRP)-induced neurogenic dural vasodilation was elicited in the presence of the enantiomers using a rat closed cranial window model. RESULTS: The isometheptene enantiomers did not induce any significant contraction in human blood vessels, except in the middle meningeal artery, when they were administered at the highest concentration (100 µM). Interestingly in rats, (S)-isometheptene induced more pronounced vasopressor responses than (R)-isometheptene. However, none of these compounds affected the CGRP-induced vasodilator responses. CONCLUSION: The isometheptene enantiomers displayed a relatively safe peripheral vascular profile, as they failed to constrict the human coronary artery. These compounds do not appear to modulate neurogenic dural CGRP release, therefore, their antimigraine site of action remains to be determined.


Assuntos
Vasos Coronários/efeitos dos fármacos , Artérias Meníngeas/efeitos dos fármacos , Metilaminas/farmacologia , Transtornos de Enxaqueca , Veia Safena/efeitos dos fármacos , Adulto , Animais , Peptídeo Relacionado com Gene de Calcitonina/farmacologia , Vasos Coronários/fisiologia , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Artérias Meníngeas/fisiologia , Metilaminas/química , Metilaminas/uso terapêutico , Pessoa de Meia-Idade , Transtornos de Enxaqueca/tratamento farmacológico , Transtornos de Enxaqueca/fisiopatologia , Técnicas de Cultura de Órgãos , Ratos , Ratos Sprague-Dawley , Veia Safena/fisiologia , Estereoisomerismo , Vasoconstritores/química , Vasoconstritores/farmacologia , Vasodilatação/efeitos dos fármacos , Vasodilatação/fisiologia , Vasodilatadores/química , Vasodilatadores/farmacologia
6.
BMC Cancer ; 18(1): 79, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29334910

RESUMO

BACKGROUND: The objective of this study is to investigate the role and experience of early stage non-small cell lung cancer (NSCLC) patient in decision making process concerning treatment selection in the current clinical practice. METHODS: Stage I-II NSCLC patients (surgery 55 patients, SBRT 29 patients, median age 68) were included in this prospective study and completed a questionnaire that explored: (1) perceived patient knowledge of the advantages and disadvantages of the treatment options, (2) experience with current clinical decision making, and (3) the information that the patient reported to have received from their treating physician. This was assessed by multiple-choice, 1-5 Likert Scale, and open questions. The Decisional Conflict Scale was used to assess the decisional conflict. Health related quality of life (HRQoL) was measured with SF-36 questionnaire. RESULTS: In 19% of patients, there was self-reported perceived lack of knowledge about the advantages and disadvantages of the treatment options. Seventy-four percent of patients felt that they were sufficiently involved in decision-making by their physician, and 81% found it important to be involved in decision making. Forty percent experienced decisional conflict, and one-in-five patients to such an extent that it made them feel unsure about the decision. Subscores with regard to feeling uninformed and on uncertainty, contributed the most to decisional conflict, as 36% felt uninformed and 17% of patients were not satisfied with their decision. HRQoL was not influenced by patient experience with decision-making or patient preferences for shared decision making. CONCLUSIONS: Dutch early-stage NSCLC patients find it important to be involved in treatment decision making. Yet a substantial proportion experiences decisional conflict and feels uninformed. Better patient information and/or involvement in treatment-decision-making is needed in order to improve patient knowledge and hopefully reduce decisional conflict.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/epidemiologia , Carcinoma Pulmonar de Células não Pequenas/psicologia , Tomada de Decisão Clínica , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Tomada de Decisões , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Participação do Paciente/psicologia , Relações Médico-Paciente , Estudos Prospectivos , Qualidade de Vida , Inquéritos e Questionários
9.
Neth Heart J ; 24(3): 161-70, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26728051

RESUMO

The prevalence of patients with congenital heart disease (CHD) has increased over the last century. As a result, the number of CHD patients presenting with late, postoperative tachyarrhythmias has increased as well. The aim of this review is to discuss the present knowledge on the mechanisms underlying both atrial and ventricular tachyarrhythmia in patients with CHD and the advantages and disadvantages of the currently available invasive treatment modalities.

10.
Acta Biomater ; 29: 161-169, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26537200

RESUMO

In order to create tissue-engineered heart valves with long-term functionality, it is essential to fully understand collagen remodeling during neo-tissue formation. Collagen remodeling is thought to maintain mechanical tissue homeostasis. Yet, the driving factor of collagen remodeling remains unidentified. In this study, we determined the collagen architecture and the geometric and mechanical properties of human native semilunar heart valves of fetal to adult age using confocal microscopy, micro-indentation and inverse finite element analysis. The outcomes were used to predict age-dependent changes in stress and stretch in the heart valves via finite element modeling. The results indicated that the circumferential stresses are different between the aortic and pulmonary valve, and, moreover, that the stress increases considerably over time in the aortic valve. Strikingly, relatively small differences were found in stretch with time and between the aortic and pulmonary valve, particularly in the circumferential direction, which is the main determinant of the collagen fiber stretch. Therefore, we suggest that collagen remodeling in the human heart valve maintains a stretch-driven homeostasis. Next to these novel insights, the unique human data set created in this study provides valuable input for the development of numerical models of collagen remodeling and optimization of tissue engineering. STATEMENT OF SIGNIFICANCE: Annually, over 280,000 heart valve replacements are performed worldwide. Tissue engineering has the potential to provide valvular disease patients with living valve substitutes that can last a lifetime. Valve functionality is mainly determined by the collagen architecture. Hence, understanding collagen remodeling is crucial for creating tissue-engineered valves with long-term functionality. In this study, we determined the structural and material properties of human native heart valves of fetal to adult age to gain insight into the mechanical stimuli responsible for collagen remodeling. The age-dependent evolutionary changes in mechanical state of the native valve suggest that collagen remodeling in heart valves is a stretch-driven process.


Assuntos
Envelhecimento/fisiologia , Colágeno/metabolismo , Valvas Cardíacas/crescimento & desenvolvimento , Modelos Cardiovasculares , Estresse Mecânico , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade
12.
Perfusion ; 30(8): 643-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25713053

RESUMO

UNLABELLED: A common effect of autologous blood withdrawal before cardiopulmonary bypass (CPB) is a decrease in haematocrit (Hct) and haemoglobin (Hb) content. A refinement of this technique is autologous blood withdrawal with the sequestration of platelet rich plasma (PRP) and red blood cells (RBCs). METHODS: One hundred and four patients were included in a randomized study stratified into three groups: the autologous blood withdrawal group (Group 1), the autologous blood withdrawal group with blood loss sequestration (Group 2) and the control group (Control group). In Group 1, the amount of withdrawn blood was transfused after CPB. In Group 2, the RBCs were transfused immediately after sequestration and the PRP was transfused after the termination of CPB. In the Control group, no autologous blood withdrawal was employed. The following variables were analysed: blood loss, blood products transfusion, fluid transfusion, diuresis, haematological and coagulation data and the duration of the operation and intensive care unit stay. RESULTS: We found no significant differences in peri-operative blood loss and transfused blood products among the three groups. There was a trend towards a lower amount of transfused fresh frozen plasma (FFP) for Group 1 (p =0.057) in the operation room (OR). The use of plasma expanders post-CPB was significantly higher in the Control group (p=0.024). RBCs coming from the auto-transfusion device were, for Group 1, significantly lower (p=0.007). The Hb and Hct values in Group 1, at start and end of CPB, were significantly lower (p=0.023-0.003 / 0.001-0.001, respectively). All other parameters were not significantly different. CONCLUSION: there were no significant differences between the study groups. This randomized trial shows that, although sequestration immediately after autologous blood withdrawal has no added value, autologous blood withdrawal in patients with a normal pre-operative Hb and Hct is simple, inexpensive and allows for autologous blood transfusion.


Assuntos
Transfusão de Componentes Sanguíneos , Perda Sanguínea Cirúrgica/prevenção & controle , Transfusão de Sangue Autóloga , Ponte de Artéria Coronária/efeitos adversos , Hemoglobinas/análise , Idoso , Estudos de Casos e Controles , Eritrócitos , Feminino , Hematócrito , Humanos , Masculino , Perfusão , Plasmaferese , Cuidados Pré-Operatórios , Estudos Prospectivos
13.
Perfusion ; 30(4): 323-31, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25122118

RESUMO

OBJECTIVE: Priming-related hemodilution is the culprit behind excessive body water accumulation, postoperative coagulopathy and enhanced blood transfusion in infant cardiac surgery patients. In this retrospective, observational study, clinical data were analyzed to assess the effect of conventional ultrafiltration on allogenic blood transfusion and patient clinical outcome. METHODS: All infants with a bodyweight up to 10 kg who underwent consequent cardiac surgery in 2011 and 2012 were eligible for the audit. Seventy patients, operated in accordance with existing pediatric protocol, enrolled in the control group. The study group consisted of 55 patients who were operated employing conventional ultrafiltration during bypass and recently adjusted hematocrit targets. The following variables were primarily investigated: hematocrit and colloid osmotic pressure value, total volume of blood products transfused and duration of postoperative mechanical ventilation. Secondary outcome measures were: postoperative urine production, postoperative blood loss, length of stay at the intensive care unit and hospital stay. RESULTS: There were no significant differences between the groups in relation to demographics or hematological and cardiopulmonary bypass data. The ultrafiltration volume removed from circulation during bypass in the study group was 171 ± 99 ml. No significant difference between the groups was found with regard to the total allogenic blood transfusion (study group 216 ± 92 ml versus control group 191 ±93 ml; p = 0.136). All recorded clinical end points, duration of mechanical ventilation, duration of chest tube in situ, stay in ICU and stay in hospital, were similar between the groups. CONCLUSIONS: Routine use of conventional ultrafiltration during the cardiac surgery for patients with a bodyweight less than 10 kg was a safe technique that allowed us to achieve higher hematocrit levels at the end of the operation without additional transfusions of allogenic blood. On the other hand, ultrafiltration did not improve the clinical end points.


Assuntos
Transfusão de Sangue , Peso Corporal , Ponte Cardiopulmonar , Feminino , Hematócrito , Humanos , Lactente , Masculino , Estudos Retrospectivos , Ultrafiltração
14.
Eur Heart J Acute Cardiovasc Care ; 4(1): 96-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24585940

RESUMO

A 25-year-old man with a ventricular septal defect resulting from a stab wound to his chest was admitted to our hospital. Because of extensive comorbidity and favourable location, transcatheter closure with an Amplatzer device was preferred over surgical repair. Ventricular septal defects are an uncommon complication of cardiac trauma, but when they do occur from this cause, they often have more dramatic consequences. Transcatheter closure is an attractive, less-invasive alternative in patients with increased surgical risk, multiple previous surgical interventions, or poorly accessible defects.


Assuntos
Septo Interventricular/lesões , Ferimentos Perfurantes/cirurgia , Adulto , Cateterismo Cardíaco , Humanos , Masculino , Dispositivo para Oclusão Septal , Resultado do Tratamento , Septo Interventricular/cirurgia
15.
Neth Heart J ; 22(7-8): 336-43, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24915773

RESUMO

AIMS: Assess and compare among Dutch cardiothoracic surgeons and cardiologists: opinion on (1) patient involvement, (2) conveying risk in aortic valve selection, and (3) aortic valve preferences. METHODS AND RESULTS: A survey among 117 cardiothoracic surgeons and cardiologists was conducted. Group responses were compared using the Mann-Whitney U test. Most respondents agreed that patients should be involved in decision-making, with surgeons leaning more toward patient involvement (always: 83 % versus 50 % respectively; p < 0.01) than cardiologists. Most respondents found that ideally doctors and patients should decide together, with cardiologists leaning more toward taking the lead compared with surgeons (p < 0.01). Major risks of the therapeutic options were usually discussed with patients, and less common complications to a lesser extent. A wide variation in valve preference was noted with cardiologists leaning more toward mechanical prostheses, while surgeons more often preferred bioprostheses (p < 0.05). CONCLUSION: Patient involvement and conveying risk in aortic valve selection is considered important by cardiologists and cardiothoracic surgeons. The medical profession influences attitude with regard to aortic valve selection and patient involvement, and preference for a valve substitute. The variation in valve preference suggests that in most patients both valve types are suitable and aortic valve selection may benefit from evidence-based informed shared decision-making.

16.
Neth Heart J ; 22(6): 259-66, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24129689

RESUMO

Isolation of the pulmonary veins may be an effective treatment modality for eliminating atrial fibrillation (AF) episodes but unfortunately not for all patients. When ablative therapy fails, it is assumed that AF has progressed from a trigger-driven to a substrate-mediated arrhythmia. The effect of radiofrequency ablation on persistent AF can be attributed to various mechanisms, including elimination of the trigger, modification of the arrhythmogenic substrate, interruption of crucial pathways of conduction, atrial debulking, or atrial denervation. This review discusses the possible effects of pulmonary vein isolation on the fibrillatory process and the necessity of cardiac mapping in order to comprehend the mechanisms of AF in the individual patient and to select the optimal treatment modality.

17.
Genes Immun ; 15(2): 72-81, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24304972

RESUMO

T-cell receptor (TCR) translocations are a genetic hallmark of T-cell acute lymphoblastic leukemia and lead to juxtaposition of oncogene and TCR loci. Oncogene loci become involved in translocations because they are accessible to the V(D)J recombination machinery. Such accessibility is predicted at cryptic recombination signal sequence (cRSS) sites ('Type 1') as well as other sites that are subject to DNA double-strand breaks (DSBs) ('Type 2') during early stages of thymocyte development. As chromatin accessibility markers have not been analyzed in the context of TCR-associated translocations, various genetic and epigenetic determinants of LMO2, TAL1 and TLX1 translocation breakpoint (BP) sites and BP cluster regions (BCRs) were examined in human thymocytes to establish DSB proneness and heterogeneity of BP site involvement in TCR translocations. Our data show that DSBs in BCRs are primarily induced in the presence of a genetic element of sequence vulnerability (cRSSs, transposable elements), whereas breaks at single BP sites lacking such elements are more likely induced by chance or perhaps because of patient-specific genetic vulnerability. Vulnerability to obtain DSBs is increased by features that determine chromatin organization, such as methylation status and nucleosome occupancy, although at different levels at different BP sites.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Pontos de Quebra do Cromossomo , Proteínas de Homeodomínio/genética , Proteínas com Domínio LIM/genética , Proteínas Proto-Oncogênicas/genética , Receptores de Antígenos de Linfócitos T/genética , Sequência de Bases , Criança , Pré-Escolar , Quebras de DNA de Cadeia Dupla , Metilação de DNA , Epigênese Genética , Humanos , Lactente , Recém-Nascido , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Proteínas Proto-Oncogênicas c-bcr/genética , Análise de Sequência de DNA , Proteína 1 de Leucemia Linfocítica Aguda de Células T , Timócitos/citologia , Translocação Genética/genética , Recombinação V(D)J/genética
18.
J Biomech ; 46(12): 2075-81, 2013 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-23849135

RESUMO

Transcatheter heart valve replacement is an attractive and promising technique for congenital as well as acquired heart valve disease. In this procedure, the replacement valve is mounted in a stent that is expanded at the aimed valve position and fixated by clamping. However, for this technique to be appropriate for pediatric patients, the material properties of the host tissue need to be determined to design stents that can be optimized for this particular application. In this study we performed equibiaxial tensile tests on four adult ovine pulmonary artery walls and compared the outcomes with one pediatric pulmonary artery. Results show that the pediatric pulmonary artery was significantly thinner (1.06 ± 0.36 mm (mean ± SD)) than ovine tissue (2.85 ± 0.40 mm), considerably stiffer for strain values that exceed the physiological conditions (beyond 50% strain in the circumferential and 60% in the longitudinal direction), more anisotropic (with a significant difference in stiffness between the longitudinal and circumferential directions beyond 60% strain) and presented stronger non-linear stress-strain behavior at equivalent strains (beyond 26% strain) compared to ovine tissue. These discrepancies suggest that stents validated and optimized using the ovine pre-clinical model might not perform satisfactorily in pediatric patients. The material parameters derived from this study may be used to develop stent designs for both applications using computational models.


Assuntos
Elasticidade , Próteses Valvulares Cardíacas , Modelos Cardiovasculares , Desenho de Prótese , Artéria Pulmonar/fisiologia , Stents , Adulto , Animais , Pré-Escolar , Humanos , Ovinos , Resistência à Tração
19.
Neth Heart J ; 21(11): 517-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23605476
20.
Neth Heart J ; 21(1): 21-7, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23229811

RESUMO

BACKGROUND: The disease burden of patients with severe aortic stenosis is not often explored, while the incidence is increasing and many patients who have an indication for aortic valve replacement are not referred for surgery. We studied the quality of life of 191 patients with severe aortic stenosis, hypothesising that symptomatic patients have a far worse quality of life than the general population, which could enforce the indication for surgery. METHODS: The SF-36v2 Health Survey was completed by 191 consecutive patients with symptomatic or asymptomatic severe aortic stenosis. RESULTS: Asymptomatic patients (n = 59) had health scores comparable with the general Dutch population but symptomatic patients (n = 132) scored significantly lower across different age categories. Physical functioning, general health and vitality were impaired, as well as social functioning and emotional well-being. There was no relation between degree of stenosis and physical or mental health scores. CONCLUSIONS: Both physical and emotional problems have a major impact on normal daily life and social functioning of symptomatic patients with severe aortic stenosis, regardless of age. If the aortic stenosis is above the 'severe' threshold, the degree of stenosis does not predict disease burden. These results encourage to reconsider a conservative approach in symptomatic patients with severe aortic stenosis. Using the SF-36v2 Health Survey together with this study, an individual patient's quality of life profile can be assessed and compared with the patient group or with the general population. This can assist in decision making for the individual patient.

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