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1.
J Vasc Surg ; 65(6): 1830-1838, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28359714

RESUMO

OBJECTIVE: Sac shrinkage is considered a reliable surrogate marker of success after endovascular aneurysm repair (EVAR). Whereas sac shrinkage is the best expected outcome, predictive factors of sac shrinkage remain unclear. The aim of this study was to identify the role of preoperative and postoperative influencing factors of sac reduction after EVAR. METHODS: Online searches across MEDLINE, Embase, and Cochrane Library medical databases were simultaneously performed. Study effects were pooled using a random-effects model, and forest plots were generated for every potential influencing factor. RESULTS: A total of 24 studies with 14,754 patients were included (mean age, 73.4 years; 76% male). At a mean follow-up of 24 months, the pooled shrinkage proportion was 47%. Random-effects meta-analysis revealed that renal impairment (odds ratio [OR], 0.74; 95% confidence interval [CI], 0.57-0.96), type I endoleaks (OR, 0.17; 95% CI, 0.08-0.39), type II endoleaks (OR, 0.21; 95% CI, 0.14-0.33), and combined type I and type II endoleaks (OR, 0.32; 95% CI, 0.22-0.47) were found to prevent sac shrinkage, whereas hypercholesterolemia (OR, 1.24; 95% CI, 1.02-1.51) and smoking (OR, 1.32; 95% CI, 1.17-1.49) have a significant positive impact on sac shrinkage. In addition, there was a trend toward the association between shrinkage and statin therapy (OR, 4.07; 95% CI, 1.02-16.32) and nearly significant negative impacts of coronary artery disease (OR, 0.84; 95% CI, 0.70-1.01), diabetes (OR, 0.79; 95% CI, 0.60-1.04), and sac thrombus (OR, 0.88; 95% CI, 0.77-1.01) on sac shrinkage. CONCLUSIONS: In this large meta-analysis of patients undergoing EVAR, we found that several comorbidity and postoperative factors were associated with postoperative sac shrinkage. These findings may contribute to a better understanding of the shrinkage process of patients undergoing EVAR.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular , Procedimentos Endovasculares , Idoso , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Implante de Prótese Vascular/efeitos adversos , Comorbidade , Procedimentos Endovasculares/efeitos adversos , Feminino , Humanos , Masculino , Razão de Chances , Indução de Remissão , Fatores de Risco , Resultado do Tratamento
2.
Ann Vasc Surg ; 41: 284-293, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27903482

RESUMO

BACKGROUND: Type II endoleaks (T2Es) remain the Achilles heel of endovascular aneurysm repair (EVAR), involving a close follow-up and sometimes leading to reintervention. Identifying risk factors impacting T2Es is of concern to improve decision making and optimize follow-up. However, it has led to contradictory results, with supporting evidence for the majority of factors being weak. METHODS: A systematic review and meta-analysis was conducted to study risk factors of T2Es following EVAR to identify risk factors and measure their dedicated strength of association. Using a literature search of MEDLINE, EMBASE, and the Cochrane Library, 31 retrospective studies including a total of 15,793 patients were identified and fulfilled the strict specified inclusion criteria. Random-effects meta-analysis was conducted for each factor to combine effect estimate across studies. A total of 21 factors related to demography, preoperative treatment, comorbidity, and morphology were statistically pooled. RESULTS: On the basis of the pooled odds ratios and their 95% confidence intervals, patency of aortic side branches, represented by the patency of the inferior mesenteric artery, lumbar arteries, or total number of aortic side branches, were found to be significant harmful risk factors of T2Es. Women were also found to have nearly significant higher risk of developing T2Es than men. On the contrary, the following were found to have a significant protective role: smoking, peripheral artery disease, and thrombus load, represented by the maximum thickness at the maximum aneurysm diameter, the presence of circumferential thrombus, or the presence of thrombus at the level of inferior mesenteric artery. CONCLUSION: Identifying significant risk factors of development of T2Es is mandatory to improve decision making and optimize surveillance planning in EVAR.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular/efeitos adversos , Endoleak/etiologia , Procedimentos Endovasculares/efeitos adversos , Aneurisma da Aorta Abdominal/fisiopatologia , Endoleak/fisiopatologia , Feminino , Humanos , Modelos Logísticos , Masculino , Razão de Chances , Medição de Risco , Fatores de Risco , Resultado do Tratamento
3.
Ann Vasc Surg ; 40: 19-27, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27903486

RESUMO

BACKGROUND: The risk of long-term complications after endovascular aneurysm repair (EVAR) is still higher than open surgery and is a critical issue. This study aims to make available reliable statistical predictive models of complications after EVAR. METHODS: Two hundred and thirteen patients who underwent EVAR between 2002 and 2012 were included in this study. The preoperative computed tomography scans were analyzed with a dedicated workstation to provide spatially correct 3-dimensional data. Age, gender, operation-related factors, and 21 morphologic variables were measured and included in the analyses. Five postoperative outcomes were studied. After an initial selection of predictors based on univariate analysis, binomial logistic regression models were proposed for each outcome. The ability to predict each outcome was assessed with receiver operating characteristic curves considering that an area under the curve (AUC) > 0.70 is generally considered sufficiently accurate. RESULTS: The mean age was 74.8 ± 8.6 years with a mean follow-up of 43.8 ± 22.1 months. Respectively, rates and risk factors of each outcome were 25.3% (n = 51) for abdominal aortic aneurysm (AAA) enlargement (age, number of patent sac branches, iliac calcifications and tortuosity, aneurysmal thrombus), 7% (n = 15) for type IA endoleak (neck calcification and AAA diameter), 3.7% (n = 8) for type IB endoleak (iliac tortuosity, AAA diameter, neck thrombus), 19.8% (n = 40) for type II endoleak (female, number of patent sac branches), and 25.9% (n = 55) for reintervention from any cause (neck calcification). The risk associated to each outcome can be calculated with a combination of these different preoperative variables. AUC for each outcome were 79.6% for AAA enlargement, 70.4% for reintervention, 81.3% for type IA endoleak, 92.3% for type IB endoleak, 70.6% for type II endoleak. CONCLUSIONS: This study shows that an exhaustive description of the preoperative anatomy before EVAR is a powerful and reliable tool to predict the risk of developing the most common complications after EVAR.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular/efeitos adversos , Endoleak/etiologia , Procedimentos Endovasculares/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aortografia/métodos , Área Sob a Curva , Distribuição de Qui-Quadrado , Angiografia por Tomografia Computadorizada , Endoleak/diagnóstico por imagem , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Valor Preditivo dos Testes , Curva ROC , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Trombose/etiologia , Fatores de Tempo , Resultado do Tratamento , Calcificação Vascular/etiologia
4.
Med Eng Phys ; 77: 69-79, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31926831

RESUMO

We present a multi-scale CFD-based study conducted in a cohort of 11 patients with coarctation of the aorta (CoA). The study explores the potential for implementation of a workflow using non-invasive routinely collected medical imaging data and clinical measurements to provide a more detailed insight into local aortic haemodynamics in order to support clinical decision making. Our approach is multi-scale, using a reduced-order model (1D/0D) and an optimization process for the personalization of patient-specific boundary conditions and aortic vessel wall parameters from non-invasive measurements, to inform a more complex model (3D/0D) representing 3D aortic patient-specific anatomy. The reliability of the modelling approach is investigated by comparing 3D/0D model pressure drop estimation with measured peak gradients recorded during diagnostic cardiac catheterization and 2D PC-MRI flow rate measurements in the descending aorta. The current study demonstrated that the proposed approach requires low levels of user interaction, making it suitable for the clinical setting. The agreement between computed blood pressure drop and catheter measurements is 10  ±  8 mmHg at the coarctation site. The comparison between CFD derived and catheter measured pressure gradients indicated that the model has to be improved, suggesting the use of time varying pressure waveforms to further optimize the tuning process and modelling assumptions.


Assuntos
Coartação Aórtica/fisiopatologia , Hidrodinâmica , Modelagem Computacional Específica para o Paciente , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pressão , Adulto Jovem
5.
IEEE Trans Inf Technol Biomed ; 10(2): 417-20, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16617632

RESUMO

This paper describes an extended ray casting scheme for three-dimensional (3-D) navigation into the heart cavities for preoperative planning using multislice X-ray computed tomography data. The key benefit is that artifacts due to contrast inhomogeneities can be eliminated during volume traversal, thus improving the visual perception of the endocardial wall.


Assuntos
Procedimentos Cirúrgicos Cardiovasculares/métodos , Coração/diagnóstico por imagem , Imageamento Tridimensional/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Cirurgia Assistida por Computador/métodos , Tomografia Computadorizada Espiral/métodos , Interface Usuário-Computador , Algoritmos , Inteligência Artificial , Humanos , Cuidados Pré-Operatórios/métodos , Intensificação de Imagem Radiográfica/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
IEEE Trans Biomed Eng ; 60(5): 1353-62, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23269745

RESUMO

Endovascular repair of abdominal aortic aneurysms is a well-established technique throughout the medical and surgical communities. Although increasingly indicated, this technique does have some limitations. Because intervention is commonly performed under fluoroscopic control, 2-D visualization of the aneurysm requires the injection of a contrast agent. The projective nature of this imaging modality inevitably leads to topographic errors, and does not give information on arterial wall quality at the time of deployment. A specially adapted intraoperative navigation interface could increase deployment accuracy and reveal such information, which preoperative 3-D imaging might otherwise provide. One difficulty is the precise matching of preoperative data (images and models) and intraoperative observations affected by anatomical deformations due to tool-tissue interactions. Our proposed solution involves a finite-element-based preoperative simulation of tool-tissue interactions, its adaptive tuning regarding patient specific data, and the matching with intraoperative data. The biomechanical model was first tuned on a group of ten patients and assessed on a second group of eight patients.


Assuntos
Aneurisma da Aorta Abdominal/patologia , Análise de Elementos Finitos , Imageamento Tridimensional/métodos , Cirurgia Assistida por Computador/métodos , Idoso , Idoso de 80 Anos ou mais , Angiografia , Aorta Abdominal/diagnóstico por imagem , Aorta Abdominal/patologia , Aorta Abdominal/cirurgia , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular , Simulação por Computador , Humanos , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
7.
Conf Proc IEEE Eng Med Biol Soc ; 2006: 1754-7, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17945665

RESUMO

Aneurysms are a local dilatation of a vessel wall of at least twice the normal diameter (commonly accepted definition). They are asymptomatic and rupture is often lethal. Thus, prediction of rupture is an important stake. Aiming at a diagnosis tool relying on patient specific data and general physiological values, we created a virtual aneurysm model based on real imaging data. Fluid/structure interaction (FSI) simulations were made to compute the displacement and stress for the wall. For the fluid, the only in vivo measures used were for the inlet velocity. The mandatory output boundary condition has been implemented with the first order Windkessel model equations. Structure has been much more complicated to handle because of the association of a realistic geometry (no symmetry) and a full fluid/structure interaction approach. We used surface elements to stabilize the structure and to model surrounding organs. Validation parameters are the displacement, the Von Mises stress and the pressure profile at the outlet. The main difference with other studies relies on the association of all these elements in order to prepare industrial applications as the main goal of this study was to build an automated tool easy to use by people who are not experts in numerical simulation.


Assuntos
Aorta Abdominal/fisiopatologia , Aneurisma da Aorta Abdominal/fisiopatologia , Velocidade do Fluxo Sanguíneo , Pressão Sanguínea , Modelos Cardiovasculares , Fluxo Pulsátil , Simulação por Computador , Elasticidade , Humanos , Resistência ao Cisalhamento , Estresse Mecânico
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