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1.
J Biomech Eng ; 146(2)2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-37978048

RESUMO

In recent years, transcatheter edge-to-edge repair (TEER) has been widely adopted as an effective treatment for mitral regurgitation (MR). The aim of this study is to develop a personalized in silico model to predict the effect of edge-to-edge repair in advance to the procedure for each individual patient. For this purpose, we propose a combination of a valve deformation model for computing the mitral valve (MV) orifice area (MVOA) and a lumped parameter model for the hemodynamics, specifically mitral regurgitation volume (RVol). Although we cannot obtain detailed information on the three-dimensional flow field near the mitral valve, we can rapidly simulate the important medical parameters for the clinical decision support. In the present method, we construct the patient-specific pre-operative models by using the parameter optimization and then simulate the postoperative state by applying the additional clipping condition. The computed preclip MVOAs show good agreement with the clinical measurements, and the correlation coefficient takes 0.998. In addition, the MR grade in terms of RVol also has good correlation with the grade by ground truth MVOA. Finally, we try to investigate the applicability for the predicting the postclip state. The simulated valve shapes clearly show the well-known double orifice and the improvement of the MVOA, compared with the preclip state. Similarly, we confirmed the improved reverse flow and MR grade in terms of RVol. A total computational time is approximately 8 h by using general-purpose PC. These results obviously indicate that the present in silico model has good capability for the assessment of edge-to-edge repair.


Assuntos
Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral , Humanos , Insuficiência da Valva Mitral/cirurgia , Implante de Prótese de Valva Cardíaca/métodos , Valva Mitral/cirurgia , Resultado do Tratamento , Simulação por Computador
2.
Eur Heart J ; 42(30): 2924-2931, 2021 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-34240121

RESUMO

AIMS: Little is known about the prevalence of aortic aneurysms among people living with HIV (PLWH). We investigated whether HIV status is independently associated with having aortic aneurysms. Furthermore, we determined risk factors associated with aortic aneurysms in PLWH. METHODS AND RESULTS: PLWH aged ≥40 years (n = 594) were recruited from the Copenhagen Comorbidity in HIV Infection study and matched for age and sex with uninfected controls (n = 1188) from the Copenhagen General Population Study. Aortic dimensions were assessed using contrast enhanced computed tomography. Aortic aneurysms were defined according to the European Society of Cardiology guidelines, i.e. an aortic dilation of ≥50% or an infrarenal aortic diameter of ≥30 mm. Among PLWH and uninfected controls, the median (interquartile range) age was 52 (47-60) and 52 (48-61) and 88% and 90% were male, respectively. We found 46 aneurysms in 42 (7.1%) PLWH and 31 aneurysms in 29 (2.4%) uninfected controls (P < 0.001). PLWH had a significantly higher prevalence of ascending aortic aneurysms and infrarenal aortic aneurysms. In an adjusted model, HIV was independently associated with aortic aneurysms (adjusted odds ratio; 4.51 [95% confidence interval 2.56-8.08], P < 0.001). Within PLWH, obesity and hepatitis B co-infection were associated with aortic aneurysms. CONCLUSION: PLWH had four-fold higher odds of aortic aneurysms compared to uninfected controls, and HIV status was independently associated with aortic aneurysms. Among PLWH, age, obesity and hepatitis B co-infection were associated with higher odds of aortic aneurysms. Our findings suggest that increased attention to aortic aneurysms in PLWH may be beneficial.


Assuntos
Aneurisma da Aorta Abdominal , Infecções por HIV , Aneurisma da Aorta Abdominal/epidemiologia , Estudos de Coortes , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Humanos , Masculino , Estudos Prospectivos , Fatores de Risco
3.
Pflugers Arch ; 470(7): 995-1016, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29536164

RESUMO

Alternative splicing (AS) of protein-coding messenger RNAs is an essential regulatory mechanism in eukaryotic gene expression that controls the proper function of proteins. It is also implicated in the physiological regulation of mitochondria and various ion channels. Considering that mis-splicing can result in various human diseases by modifying or abrogating important physiological protein functions, a fine-tuned balance of AS is essential for human health. Accumulated data highlight the importance of alternatively spliced isoforms in various diseases, including neurodegenerative disorders, cancer, immune and infectious diseases, cardiovascular diseases, and metabolic conditions. However, basic understanding of disease mechanisms and development of clinical applications still require the integration and interpretation of physiological roles of AS. This review discusses the roles of AS in health and various diseases, while highlighting potential AS-targeting therapeutic applications.


Assuntos
Processamento Alternativo/genética , Doença/genética , Isoformas de Proteínas/genética , Animais , Humanos , RNA Mensageiro/genética
4.
Artigo em Inglês | MEDLINE | ID: mdl-38662458

RESUMO

BACKGROUND AND AIMS: The prevalence and difference in risk factors for having thoracic and abdominal aortic aneurysms in men compared to women in the general population is not well-described. This study aimed to test the hypotheses i) that cardiovascular risk factors for thoracic and abdominal aortic aneurysms differ and ii) that the prevalence of thoracic and abdominal aortic aneurysms is sex specific. METHODS: Aortic examination using computed tomography angiography was performed in 11,294 individuals (56% women), with a mean age of 62 [range 40-95] years participating in the Copenhagen General Population Study. Thoracic aortic aneurysms were defined as ascending aortic diameter ≥45 mm and descending aortic diameter ≥35 mm, abdominal aortic aneurysms were defined as abdominal aortic diameter ≥30 mm. Demographic data were obtained from questionnaires. RESULTS: Overall prevalence of aortic aneurysms in the study population included: total population 2.1%, men 4.0% and women 0.7% (p-test men vs. women p<0.001). Aortic aneurysms were independently associated with male sex, increasing age, and body surface area. While thoracic aortic aneurysms were associated with hypertension, odds ratio=2.0[95%CI:1.5-2.8], abdominal aortic aneurysms were associated with hypercholesterolemia and smoking, odds ratios=2.4[95%CI:1.6-3.6] and 3.2[95%CI:1.9-5.4]. CONCLUSIONS: Subclinical aortic aneurysms are four times more prevalent in men than women. In both sexes, increasing age and body surface area are risk factors for aortic aneurysms of any anatomical location. Whereas arterial hypertension is a risk factor for thoracic aortic aneurysms, hypercholesterolemia and smoking are risk factors for abdominal aortic aneurysms.

5.
Phys Med Biol ; 69(3)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38100829

RESUMO

Objective. Accurate extraction of mitral valve shape from clinical tomographic images acquired in patients has proven useful for planning surgical and interventional mitral valve treatments. However, manual extraction of the mitral valve shape is laborious, and the existing automatic extraction methods have not been sufficiently accurate. In this paper, we propose a fully automated method of extracting mitral valve shape from computed tomography (CT) images for the all phases of the cardiac cycle.Approach. This method extracts the mitral valve shape based on DenseNet using both the original CT image and the existence probability maps of the mitral valve area inferred by U-Net as input. A total of 1585 CT images from 204 patients with various cardiac diseases including mitral regurgitation were collected and manually annotated for mitral valve region. The proposed method was trained and evaluated by 10-fold cross validation using the collected data and was compared with the method without the existence probability maps.Main results. The mean error of shape extraction error in the proposed method is 0.88 mm, which is an improvement of 0.32 mm compared with the method without the existence probability maps.Significance. We present a novel fully automatic mitral valve extraction method from input to output for all phases of 4D CT images. We suggest that the accuracy of mitral valve shape extraction is improved by using existence probability maps.


Assuntos
Valva Mitral , Tomografia Computadorizada por Raios X , Humanos , Valva Mitral/diagnóstico por imagem , Valva Mitral/cirurgia , Tomografia Computadorizada por Raios X/métodos
6.
AIDS ; 37(11): 1765-1767, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37534728

RESUMO

Here, we investigate if peripheral T-cell activation and proportion of Th17 and T-regulatory cells (Tregs) are associated with aortic aneurysm or aortic diameter in people with HIV. Aorta was examined by computed tomography scans and T-cells by flow cytometry in 428 participants, and aortic aneurysm was found in 32 participants. None of the T-cell subsets were associated with aortic aneurysm, but activated T-cells and Tregs had opposite association to aorta diameter indicating an inverse impact.


Assuntos
Aneurisma Aórtico , Infecções por HIV , Humanos , Linfócitos T Reguladores , Infecções por HIV/complicações , Subpopulações de Linfócitos T , Ativação Linfocitária , Aneurisma Aórtico/diagnóstico por imagem , Células Th17
7.
Front Immunol ; 14: 1115894, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36817421

RESUMO

Introduction: People living with HIV (PLWH) are at twice the risk of developing cardiovascular diseases and have more than four times higher odds of aortic aneurysm (AA) than the uninfected population. However, biomarkers of AA in PLWH are yet to be discovered. We aimed to investigate whether circulating biomarkers reflecting platelet activation, hemostasis and endothelial disruption, i.e. sCD40L, D-dimer, syndecan-1, and thrombomodulin, were associated with AA in PLWH. Methods: Five hundred seventy one PLWH from the Copenhagen Comorbidity in HIV Infection (COCOMO) study ≥40 years of age with an available contrast-enhanced CT scan as well as available biomarker analyses were included. The biomarkers were analyzed on thawed plasma. For each biomarker, we defined high level as a concentration in the upper quartile and low level as a concentration below the upper quartile. For D-dimer, the cut-off was defined as the lower limit of detection. Using unadjusted and adjusted logistic and linear regression models, we analyzed associations between AA and sCD40L, D-dimer, syndecan-1, and thrombomodulin, respectively in PLWH. Results: PLWH had median (IQR) age 52 years (47-60), 88% were male, median (IQR) time since HIV diagnosis was 15 years (8-23), and 565 (99%) were currently on antiretroviral treatment. High level of sCD40L was associated with lower odds of AA in both unadjusted (odds ratio, OR, 0.23 (95% CI 0.07-0.77; P=0.017)) and adjusted models (adjusted OR, aOR, 0.23 (95% CI 0.07-0.78; P=0.019)). Detectable level of D-dimer was associated with higher odds of AA in both unadjusted (OR 2.76 (95% CI 1.34-5.67; P=0.006)) and adjusted models (aOR 2.22 (95% CI 1.02-4.85; P=0.045)). Conclusions: SCD40L was associated with lower odds of AA whereas D-dimer was independently associated with higher odds of AA in PLWH. This calls for further investigations into specific biomarkers to aid early diagnosis of AA in PLWH.


Assuntos
Aneurisma Aórtico , Infecções por HIV , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Infecções por HIV/complicações , Sindecana-1 , Trombomodulina , Fatores de Risco , Ativação Plaquetária , Biomarcadores
8.
BMJ Open ; 13(5): e071885, 2023 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-37208133

RESUMO

INTRODUCTION: Vitamin K has been suggested to have protective effects against progression of vascular calcification and development of cardiovascular disease (CVD). However, few well-powered randomised controlled trials have examined whether vitamin K prevents progression of vascular calcification in individuals from the general population. The aim of the InterVitaminK trial is to investigate the effects of vitamin K supplementation (menaquinone-7, MK-7) on cardiovascular, metabolic, respiratory and bone health in a general ageing population with detectable vascular calcification. METHODS AND ANALYSIS: The InterVitaminK trial is a randomised, double-blinded, placebo-controlled, trial. A total of 450 men and women aged 52-82 years with detectable coronary artery calcification (CAC), but without manifest CVD, will be randomised (1:1) to receive daily MK-7 (333 µg/day) or placebo tablets for 3 years. Health examinations are scheduled at baseline, and after 1, 2 and 3 years of intervention. Health examinations include cardiac CT scans, measurements of arterial stiffness, blood pressure, lung function, physical function, muscle strength, anthropometric measures, questionnaires on general health and dietary intake, and blood and urine sampling. The primary outcome is progression of CAC from baseline to 3-year follow-up. The trial has 89% power to detect a between-group difference of at least 15%. Secondary outcomes are bone mineral density, pulmonary function and biomarkers of insulin resistance. ETHICS AND DISSEMINATION: Oral MK-7 supplementation is considered safe and has not been found to cause severe adverse events. The Ethical Committee of the Capital Region (H-21033114) approved the protocol. Written informed consent is obtained from all participants and the trial is conducted in accordance with the Declaration of Helsinki II. Both negative and positive findings will be reported. TRIAL REGISTRATION NUMBER: NCT05259046.


Assuntos
Doença da Artéria Coronariana , Calcificação Vascular , Masculino , Humanos , Feminino , Vitamina K , Densidade Óssea , Vitamina K 2/farmacologia , Vitamina K 2/uso terapêutico , Pulmão , Doença da Artéria Coronariana/tratamento farmacológico , Calcificação Vascular/prevenção & controle , Suplementos Nutricionais , Dinamarca , Método Duplo-Cego , Ensaios Clínicos Controlados Aleatórios como Assunto
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