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1.
World J Pediatr Congenit Heart Surg ; 15(4): 515-518, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38711171

RESUMO

Anatomic and physiologic assessment of surgical repair of scimitar syndrome can be challenging. We evaluated the first patient who underwent the Lugones procedure in 2012 using 4D flow magnetic resonance imaging. With this technology, we demonstrate that the reconstructed right pulmonary venous return drains into the left atrium with laminar flow, just as normal pulmonary veins do.


Assuntos
Síndrome de Cimitarra , Humanos , Síndrome de Cimitarra/cirurgia , Síndrome de Cimitarra/diagnóstico por imagem , Veias Pulmonares/cirurgia , Veias Pulmonares/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Feminino , Masculino , Procedimentos Cirúrgicos Cardíacos/métodos , Fatores de Tempo
2.
Biomed Phys Eng Express ; 10(3)2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38437732

RESUMO

Thoracic aorta calcium (TAC) can be assessed from cardiac computed tomography (CT) studies to improve cardiovascular risk prediction. The aim of this study was to develop a fully automatic system to detect TAC and to evaluate its performance for classifying the patients into four TAC risk categories. The method started by segmenting the thoracic aorta, combining three UNets trained with axial, sagittal and coronal CT images. Afterwards, the surrounding lesion candidates were classified using three combined convolutional neural networks (CNNs) trained with orthogonal patches. Image datasets included 1190 non-enhanced ECG-gated cardiac CT studies from a cohort of cardiovascular patients (age 57 ± 9 years, 80% men, 65% TAC > 0). In the test set (N = 119), the combination of UNets was able to successfully segment the thoracic aorta with a mean volume difference of 0.3 ± 11.7 ml (<6%) and a median Dice coefficient of 0.947. The combined CNNs accurately classified the lesion candidates and 87% of the patients (N = 104) were accurately placed in their corresponding risk categories (Kappa = 0.826, ICC = 0.9915). TAC measurement can be estimated automatically from cardiac CT images using UNets to isolate the thoracic aorta and CNNs to classify calcified lesions.


Assuntos
Aorta Torácica , Aprendizado Profundo , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Feminino , Cálcio , Tomografia Computadorizada por Raios X/métodos , Eletrocardiografia
3.
Diagn Interv Imaging ; 105(5): 174-182, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38148259

RESUMO

PURPOSE: Abdominal aorta calcium (AAC) burden and dilatation are associated with an increased risk of mortality. The purpose of this study was to investigate determinants of AAC and abdominal aorta size in patients with essential hypertension. MATERIALS AND METHODS: Patients with uncomplicated essential hypertension who had undergone non-enhanced abdominal CT to rule out secondary hypertension in addition to biological test were recruited between 2010 and 2018. A semi-automatic system was designed to estimate the aortic size (diameter, length, volume) and quantify the AAC from mesenteric artery to bifurcation using the Agatston score. Determinants of aortic size and those related to AAC were searched for using uni- and multivariables analyses. RESULTS: Among 293 randomly selected patients with hypertension (age 52 ± 11 [SD] years) included, 23% had resistant hypertension. Mean abdominal aorta diameter was 20.1 ± 2.1 (SD) mm. Eight (3%) patients had abdominal aorta aneurysm ≥ 30 mm and 58 (20%) had dilated abdominal aorta ≥ 27 mm. Median AAC score was 38 and calcifications were detected in the infra- and supra-renal abdominal aortic portions in 59% and 26% of the patients, respectively. After adjustment for age, male sex and body surface area, abdominal aorta diameter was positively associated with diastolic blood pressure (P = 0.0019). Smoking was the single variable associated with calcified abdominal aorta (P < 0.001) after adjustment for cofactors. In patients with calcifications of abdominal aorta, the score increased with smoking history (P < 0.001), statins treatment (P < 0.01), greater number of anti-hypertensive drugs (P < 0.01), larger abdominal aorta (P < 0.05) and greater systolic blood pressure (P < 0.05). Patients with resistant hypertension had more AAC in the supra-renal abdominal aorta portion than those without resistant hypertension (P < 0.01). CONCLUSION: In patients with essential hypertension, abdominal aorta dilation is related with diastolic blood pressure while AAC is associated with smoking history and resistant hypertension when located to the supra-renal abdominal aorta portion.


Assuntos
Aorta Abdominal , Hipertensão Essencial , Calcificação Vascular , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Aorta Abdominal/diagnóstico por imagem , Hipertensão Essencial/diagnóstico por imagem , Calcificação Vascular/diagnóstico por imagem , Adulto , Tomografia Computadorizada por Raios X , Idoso , Doenças da Aorta/diagnóstico por imagem
4.
J Am Soc Echocardiogr ; 35(11): 1159-1167.e2, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35953008

RESUMO

BACKGROUND: The assessment of cardiac chamber size in the obese population is a challenging subject. Values usually indexed to body surface area (BSA) are smaller in obese subjects and prone to overcorrection. The aims of this study were to find reference thresholds to account for the effects of obesity among a large cohort of patients and to evaluate indexing to height as an alternative to BSA. METHODS: The past 10 years of records from a single echocardiography unit were retrospectively analyzed, and 14,007 subjects without known cardiac disease were included (mean age, 45 ± 15 years; 54% women; 20% obese). Measurements included left atrial diameter, area, and volume, left ventricular (LV) end-diastolic and end-systolic diameters, aortic root diameter, and LV mass. Absolute, BSA-indexed, and height-indexed maximum thresholds (mean + 1.96 SDs) were calculated. Allometric indexing of the form variable/heightß was tested. Correlation coefficients between indexed and absolute values were calculated to evaluate their proportional association (ideally r = 1). Correlations between indexed values and body size represented residual associations to be minimized (ideally r = 0). RESULTS: The strongest association of echocardiographic measurements with body size was observed for BSA (r = 0.36-0.63), whereas the isometric and allometric height models showed lower comparable values (r = 0.28-0.48). Positive correlations with body mass index were mostly observed for left atrial size (r ≈ 0.36) and LV mass (r ≈ 0.36) measurements. Values of the scaling exponent ß for allometric height indexing were 1.72 for left atrial volume and 2.33 for LV mass. Correlations between indexed and absolute values were higher for height than BSA (0.80-0.98 vs 0.44-0.92). Correlations between indexed values and height were closer to 0 than for BSA, particularly using the allometric model. The overcorrection observed with increasing obesity class after BSA indexing was avoided after height indexing. CONCLUSIONS: Unlike BSA, height indexing provided adequate body size scaling of left heart chamber size, avoiding overcorrection using allometric models in particular.


Assuntos
Estatura , Ecocardiografia , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Masculino , Superfície Corporal , Estudos Retrospectivos , Valores de Referência , Ventrículos do Coração/diagnóstico por imagem , Obesidade/complicações , Obesidade/diagnóstico
5.
Tomography ; 7(4): 636-649, 2021 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-34842842

RESUMO

Arterial calcification is an independent predictor of cardiovascular disease (CVD) events whereas thoracic aorta calcium (TAC) detection might anticipate extracoronary outcomes. In this work, we trained six convolutional neural networks (CNNs) to detect aortic calcifications and to automate the TAC score assessment in intermediate CVD risk patients. Cardiac computed tomography images from 1415 patients were analyzed together with their aortic geometry previously assessed. Orthogonal patches centered in each aortic candidate lesion were reconstructed and a dataset with 19,790 images (61% positives) was built. Three single-input 2D CNNs were trained using axial, coronal and sagittal patches together with two multi-input 2.5D CNNs combining the orthogonal patches and identifying their best regional combination (BRC) in terms of lesion location. Aortic calcifications were concentrated in the descending (66%) and aortic arch (26%) portions. The BRC of axial patches to detect ascending or aortic arch lesions and sagittal images for the descending portion had the best performance: 0.954 F1-Score, 98.4% sensitivity, 87% of the subjects correctly classified in their TAC category and an average false positive TAC score per patient of 30. A CNN that combined axial and sagittal patches depending on the candidate aortic location ensured an accurate TAC score prediction.


Assuntos
Aorta Torácica , Doenças da Aorta , Aorta Torácica/diagnóstico por imagem , Doenças da Aorta/diagnóstico por imagem , Cálcio , Humanos , Redes Neurais de Computação , Medição de Risco , Fatores de Risco
7.
Int J Cardiol ; 326: 206-212, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33259874

RESUMO

BACKGROUND: We aimed to provide a comprehensive aortic stiffness description using magnetic resonance imaging (MRI) in patients with ascending thoracic aorta aneurysm and tricuspid (TAV-ATAA) or bicuspid (BAV) aortic valve. METHODS: This case-control study included 18 TAV-ATAA and 19 BAV patients, with no aortic valve stenosis/severe regurgitation, who were 1:1 age-, gender- and central blood pressures (BP)-matched to healthy volunteers. Each underwent simultaneous aortic MRI and BP measurements. 3D anatomical MRI provided aortic diameters. Stiffness indices included: regional ascending (AA) and descending (DA) aorta pulse wave velocity (PWV) from 4D flow MRI; local AA and DA strain, distensibility and theoretical Bramwell-Hill (BH) model-based PWV, as well as regional arch PWV from 2D flow MRI. RESULTS: Patient groups had significantly higher maximal AA diameter (median[interquartile range], TAV-ATAA: 47.5[42.0-51.3]mm, BAV: 45.0[41.0-47.0]mm) than their respective controls (29.1[26.8-31.8] and 28.1[26.0-32.0]mm, p < 0.0001), while BP were similar (p ≥ 0.25). Stiffness indices were significantly associated with age (ρ ≥ 0.33), mean BP (arch PWV: ρ = 0.25, p = 0.05; DA distensibility: ρ = -0.30, p = 0.02) or AA diameter (arch PWV: ρ = 0.28, p = 0.03; DA PWV: ρ = 0.32, p = 0.009). None of them, however, was significantly different between TAV-ATAA or BAV patients and their matched controls. Finally, while direct PWV measures were significantly correlated to BH-PWV estimates in controls (ρ ≥ 0.40), associations were non-significant in TAV-ATAA and BAV groups (p ≥ 0.18). CONCLUSIONS: The overlap of MRI-derived aortic stiffness indices between patients with TAV or BAV aortopathy and matched controls highlights another heterogeneous feature of aortopathy, and suggests the urgent need for more sensitive indices which might help better discriminate such diseases.


Assuntos
Doença da Válvula Aórtica Bicúspide , Doenças das Valvas Cardíacas , Rigidez Vascular , Valva Aórtica/diagnóstico por imagem , Estudos de Casos e Controles , Doenças das Valvas Cardíacas/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Análise de Onda de Pulso
8.
Comput Methods Biomech Biomed Engin ; 23(14): 1060-1070, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32594759

RESUMO

Abdominal aortic aneurysm is a deadly disease that can be treated with different endovascular devices that will distinctly alter the aortic morphology. Computational methods can be used to understand the effect of anatomical changes on aortic hemodynamics. We propose a standardized method to assess morphological and hemodynamic changes of the abdominal aorta through the longitudinal axis of the vessel. Patient-specific CFD simulations were used to quantify these changes for two different endografts before and after surgery. Differences in cross-sectional area, blood pressure, peak blood velocity, wall shear stress, and retrograde blood flow were accurately evidenced with the proposed methodology.


Assuntos
Aneurisma da Aorta Abdominal/fisiopatologia , Aneurisma da Aorta Abdominal/cirurgia , Procedimentos Endovasculares/métodos , Hemodinâmica , Pontos de Referência Anatômicos , Velocidade do Fluxo Sanguíneo , Prótese Vascular , Hemorreologia , Humanos , Modelos Cardiovasculares
9.
J Surg Res ; 249: 216-224, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32001387

RESUMO

Pericardium closure after cardiac surgery is recommended to prevent postoperative adhesions to the sternum. Synthetic materials have been used as substitutes, with limited results because of impaired remodeling and fibrotic tissue formation. Urinary bladder matrix (UBM) scaffolds promote constructive remodeling that more closely resemble the native tissue. The aim of the study is to evaluate the host response to UBM scaffolds in a porcine model of partial pericardial resection. Twelve Landrace pigs were subjected to a median sternotomy. A 5 × 7 cm pericardial defect was created and then closed with a 5 × 7 cm multilayer UBM patch (UBM group) or left as an open defect (control group). Animals were survived for 8 wk. End points included gross morphology, biomechanical testing, histology with semiquantitative score, and cardiac function. The UBM group showed mild adhesions, whereas the control group showed fibrosis at the repair site, with robust adhesions and injury to the coronary bed. Load at failure (gr) and stiffness (gr/mm) were lower in the UBM group compared with the native pericardium (199.9 ± 59.2 versus 405.3 ± 99.89 g, P = 0.0536 and 44.23 ± 15.01 versus 146.5 ± 24.38 g/mm, P = 0.0025, respectively). In the UBM group, the histology resembled native pericardial tissue, with neovascularization, neofibroblasts, and little inflammatory signs. In contrast, control group showed fibrotic tissue with mononuclear infiltrates and a lack of organized collagen fibers validated with a histologic score. Both groups had normal ultrasonography results without cardiac motility disorders. In this setting, UBM scaffolds showed appropriate features for pericardial repair, restoring tissue properties that could help reduce postsurgical adhesions and prevent its associated complications.


Assuntos
Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Pericárdio/cirurgia , Complicações Pós-Operatórias/prevenção & controle , Aderências Teciduais/prevenção & controle , Alicerces Teciduais , Animais , Procedimentos Cirúrgicos Cardíacos/métodos , Modelos Animais de Doenças , Matriz Extracelular , Feminino , Humanos , Pericárdio/patologia , Complicações Pós-Operatórias/etiologia , Telas Cirúrgicas , Sus scrofa , Aderências Teciduais/etiologia , Aderências Teciduais/patologia , Bexiga Urinária/citologia
10.
Eur Radiol ; 30(7): 3960-3967, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32100088

RESUMO

OBJECTIVES: In the ascending aorta, calcification density was independently and inversely associated with cardiovascular disease (CVD) risk prediction. Until now, the density of thoracic aorta calcium (TAC) was estimated as the Agatston score divided by the calcium area (DAG). We thought to analyze TAC density in a full Hounsfield unit (HU) range and to study its association with TAC volume, traditional risk factors, and CVD events. METHODS: Non-enhanced CT images of 1426 patients at intermediate risk were retrospectively reviewed. A calcium density score was estimated as the average of the maximum HU attenuation in all calcified plaques of the entire thoracic aorta (DAV). RESULTS: During a mean 4.0 years follow-up, there were 26 events for a total of 674 patients with TAC > 0. TAC volume and DAV were positively correlated (R = 0.72). The median DAV value was 457 HU (IQ 323-603 HU) and was exponentially related to DAG (R = 0.86). DAV was inversely associated with systolic pressure (p < 0.05), pulse pressure (p < 0.01), hypertension (p < 0.05), and 10-year FRS (p < 0.001) after adjusting for TAC volume. When TAC volume and DAV were included in a logistic model, a significant improvement was shown in CVD risk estimation beyond coronary artery calcium (CAC) (AUC = 0.768 vs 0.814, p < 0.05). In multivariable Cox models, TAC volume and DAV showed an independent association with CVD. CONCLUSIONS: In intermediate risk patients, TAC density was inversely associated with several risk factors after adjustment for TAC volume. A significant improvement was observed over CAC when TAC volume and density were added into the risk prediction model. KEY POINTS: • Calcifications in the aorta can be non-invasively assessed using CT images • A higher calcium score is associated with a higher cardiovascular risk • Measuring the calcifications size and the density separately can improve the risk prediction.


Assuntos
Angiografia/métodos , Aorta Torácica/diagnóstico por imagem , Doenças da Aorta/diagnóstico , Calcinose/diagnóstico , Cálcio/metabolismo , Aorta Torácica/metabolismo , Doenças da Aorta/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Medição de Risco , Fatores de Risco
11.
J Surg Res ; 246: 62-72, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31561179

RESUMO

Recurrence rates in the laparoscopic repair of the hiatal hernia range from 12% to 59%. Limitation of reinforcement has been principally the risk of adverse events caused by synthetic materials. Biologic and resorbable synthetic materials are valid alternatives. This study compares the host response to all these materials after hiatal hernia repair. A total of 20 Landrace pigs, underwent laparoscopic primary hiatal hernia repair and reinforced with a polypropylene mesh (PROLENE: polypropylene [PP]), an absorbable synthetic scaffold (GOREBIO-A: polyglycolic acid [PGA]), a urinary bladder matrix scaffold, (Gentrix: urinary bladder matrix [UBM]), or without reinforcement, control group (C). Animals were survived for 3 months. Endpoints included gross morphology, biomechanical testing, and histology. Pigs in PP and PGA groups showed fibrosis at the repair site, with robust adhesions. In UBM and C groups, only mild adhesions were found. Load at failure (gr) and stiffness (gr/mm) of PP were higher than C group (PP:2103 ± 548.3 versus C:951.1 ± 372.7, P = 0.02; PP:643.3 ± 301 versus C:152.6 ± 142.7, P = 0.01). PGA and UBM values for both parameters were in between PP and C samples. However, stiffness in UBM was tended to be lower than PP group, and approached a significant difference (643.3 ± 301 versus 243 ± 122.1, P = 0.0536). In UBM group, the histology resembled native tissue. By contrast, PP and PGA groups showed mononuclear infiltrates, fibroencapsulation, necrosis, remnants of mesh, and disorganized tissue that was validated with a histologic score. In this setting, UBM scaffolds showed the most appropriate features for hiatal hernia repair, recovering the tissue properties that can help reduce the possibility of early failure and prevent complications associated with the implanted material.


Assuntos
Materiais Biocompatíveis , Hérnia Hiatal/cirurgia , Herniorrafia/instrumentação , Prevenção Secundária/instrumentação , Alicerces Teciduais , Implantes Absorvíveis , Animais , Modelos Animais de Doenças , Feminino , Herniorrafia/métodos , Humanos , Teste de Materiais , Prevenção Secundária/métodos , Estresse Mecânico , Telas Cirúrgicas , Sus scrofa
12.
MAGMA ; 32(6): 629-642, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31230182

RESUMO

OBJECTIVE: To evaluate an automatic correction method for velocity offset errors in cardiac 4D-flow acquisitions. MATERIALS AND METHODS: Velocity offset correction was done in a plane-by-plane scheme and compared to a volumetric approach. Stationary regions were automatically detected. In vitro experiments were conducted in a phantom using two orientations and two encoding velocities (Venc). First- to third-order models were fit to the time-averaged images of the three velocity components. In vivo experiments included realistic ROIs in a volunteer superimposed to a phantom. In 15 volunteers, blood flow volume of the proximal and distal descending aorta, of the pulmonary artery (Qp) and the ascending aorta (Qs) was compared. RESULTS: Offset errors were reduced after correction with a third-order model, yielding residual phantom velocities below 0.6 cm/s and 0.4% of Venc. The plane-by-plane correction method was more effective than the volumetric approach. Mean velocities through superimposed ROIs of a volunteer vs phantom were highly correlated (r2 = 0.96). The significant difference between proximal and distal descending aortic flows was decreased after correction from 8.1 to - 1.4 ml (p < 0.001) and Qp/Qs reduced from 1.08 ± 0.09 to 1.01 ± 0.05. DISCUSSION: An automatic third-order model corrected velocity offset errors in 4D-flow acquisitions, achieving acceptable levels for clinical applications.


Assuntos
Aorta Torácica/diagnóstico por imagem , Coração/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética , Reconhecimento Automatizado de Padrão/métodos , Artéria Pulmonar/diagnóstico por imagem , Adolescente , Adulto , Algoritmos , Aorta Abdominal/diagnóstico por imagem , Eletrocardiografia , Feminino , Voluntários Saudáveis , Hemodinâmica , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Imagens de Fantasmas , Reprodutibilidade dos Testes , Adulto Jovem
13.
Vasc Endovascular Surg ; 52(8): 621-628, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30058480

RESUMO

OBJECTIVES:: To evaluate the effects on aortoiliac fluid dynamics after the implantation of an endograft based on endovascular aneurysm sealing (EVAS) versus endovascular aneurysm repair (EVAR) strategy. METHODS:: An adaptive geometrical deformable model was used for aortic lumen segmentation in 8 patients before and after the surgery. Abdominal aneurysms were treated with an endograft based on the EVAS system (Nellix, n = 4) and with a device based on an anatomical fixation technology (n = 4). Pressure, blood velocity, and wall shear stress (WSS) were estimated at different aortic regions using computational fluid dynamics methods. Physiologic inlet/outlet flow values at the abdominal aorta, the celiac trunk, and the mesenteric and the renal arteries were set. Pressure references were set at iliac arteries outlet. RESULTS:: Maximum aneurysm sizes were similar for both groups in the preoperative scans. The lumen area was lower after EVAR ( P < .05) and EVAS ( P < .01) compared to preoperative aortic lumen sizes. Pressure increase was higher in the proximal abdominal aorta after EVAS compared to EVAR (2.3 ± 0.3 mm Hg vs 0.9 ± 0.3 mm Hg, P < .001). Peak blood velocities inside the endografts were 3-fold higher for EVAS compared to EVAR (54 ± 5 cm/s vs 17 ± 4 cm/s, P < .01). Velocities at the iliac arteries also remained higher for EVAS (38 ± 4 cm/s vs 24 ± 4 cm/s, P < .05). Peak WSS at the iliac arteries remained higher for EVAS compared to EVAR group ( P < .05). CONCLUSION:: The significant modification of the aortic bifurcation anatomy after EVAS alters aortoiliac fluid dynamics, showing a pressure impact at the renal arteries level and an acceleration of the blood velocity at the iliac region with a concomitant increase in peak WSS.


Assuntos
Aorta Abdominal/cirurgia , Aneurisma da Aorta Abdominal/cirurgia , Implante de Prótese Vascular , Procedimentos Endovasculares , Hemodinâmica , Artéria Ilíaca/cirurgia , Modelos Cardiovasculares , Modelagem Computacional Específica para o Paciente , Idoso , Idoso de 80 Anos ou mais , Aorta Abdominal/diagnóstico por imagem , Aorta Abdominal/fisiopatologia , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/fisiopatologia , Pressão Arterial , Velocidade do Fluxo Sanguíneo , Prótese Vascular , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/instrumentação , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/instrumentação , Humanos , Hidrodinâmica , Artéria Ilíaca/diagnóstico por imagem , Artéria Ilíaca/fisiopatologia , Masculino , Estudos Retrospectivos , Stents , Resultado do Tratamento
14.
J Surg Res ; 204(2): 344-350, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27565070

RESUMO

BACKGROUND: Laparoscopic repair of the hiatal hernia is associated with a recurrence rate between 12% and 42% depending on the defect size. Although the impact of hiatal reinforcement on long-term recurrence remains controversial, the main limitation of this approach has been the risk of adverse events related with the use of synthetic materials in the vicinity of the esophagus. METHODS: A total of 14 female domestic pigs underwent laparoscopic primary hiatal hernia repair of a simulated defect in the esophageal hiatus. Seven of the hiatal repairs were reinforced with an extracellular matrix (ECM) scaffold, whereas the remaining seven served as primary repair controls. Animals were survived for 8 wk. At necropsy, after gross morphologic evaluation, samples were sent for mechanical testing and histology. RESULTS: The repaired defect site reinforced with ECM scaffolds showed a robust closure of the crura in all cases with a smooth peritoneal-like structure covering the entire repair. Average load at failure of the treated group was found to be significantly stronger than that of the controls (185.8 ± 149.7 g versus 57.5 ± 57.5 g, P < 0.05). Similarly, the stiffness was significantly higher in the treated animals (57.5 ± 26.9 g/mm versus 19.1 ± 17.5 g/mm; P < 0.01). Interestingly, there was no difference in elongation at failure (7.62 ± 2.02 mm versus 7.87 ± 3.28 mm; P = 0.44). CONCLUSIONS: In our animal survival model, we have provided evidence that the addition of an ECM to augment a primary hiatal repair leads to tissue characteristics that may decrease the possibility of early failure of the repair. This may translate to decreased recurrence rates. Further study is necessary.


Assuntos
Hérnia Hiatal/cirurgia , Herniorrafia/métodos , Alicerces Teciduais , Animais , Fenômenos Biomecânicos , Feminino , Suínos , Bexiga Urinária
15.
Atherosclerosis ; 245: 22-7, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26687999

RESUMO

OBJECTIVE: Thoracic aorta calcium (TAC) is measurable on the same computed tomography (CT) scan as coronary artery calcium (CAC) but has still unclear clinical value. We assessed TAC and CAC relations with non-cardiac vascular events history in a cohort of subjects at risk for cardiovascular disease. METHODS: We analyzed retrospectively 1000 consecutive subjects having undergone CAC detection by non-contrast multi-slice CT with measurement field longer than usual in order to measure total TAC including aortic arch calcium. We also determined partial TAC restricted to ascending and descending thoracic aorta sites by removing arch calcium from total TAC. Calcium deposits were measured with a custom made software using Agatston score. RESULTS: Compared with the rest of the cohort, the 30 subjects with non-cardiac vascular event history had higher median values [95% CI] of total TAC (282 [28-1809] vs 39 [0-333], p < 0.01) and partial TAC (4 [0-284] vs 0 [0-5], p < 0.01) but no different value of CAC (73 [0-284] vs 16 [0-148]). Odds ratio [95% CI] of having non-cardiac vascular event per 1-SD increase in log-transformed calcium value was significant for total TAC but not for CAC, if total TAC and CAC were entered separately (1.56 [1.12-2.24], p < 0.01 and 1.13 [0.86-1.50], respectively) or together (1.57 [1.10-2.32], p < 0.01 and 0.98 [0.73-1.32], respectively) in the logistic adjusted model. CONCLUSION: TAC assessment simultaneous with CAC detection provides complementary information on the extra coronary component of cardiovascular risk beyond CAC's coronary risk prediction. Further studies are required to prospectively confirm this result.


Assuntos
Aorta Torácica/diagnóstico por imagem , Doenças da Aorta/diagnóstico por imagem , Calcinose/diagnóstico por imagem , Cálcio/metabolismo , Doença da Artéria Coronariana/diagnóstico por imagem , Aorta Torácica/metabolismo , Doenças da Aorta/complicações , Doenças da Aorta/epidemiologia , Argentina/epidemiologia , Calcinose/metabolismo , Angiografia Coronária , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/etiologia , Feminino , Seguimentos , França/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores , Estudos Retrospectivos , Medição de Risco
16.
Ann Biomed Eng ; 44(5): 1381-91, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26350505

RESUMO

Rupture of abdominal aortic aneurysms (AAA) is responsible for 1-3% of all deaths among the elderly population in developed countries. A novel endograft proposes an endovascular aneurysm sealing (EVAS) system that isolates the aneurysm wall from blood flow using a polymer-filled endobag that surrounds two balloon-expandable stents. The volume of injected polymer is determined by monitoring the endobag pressure but the final AAA expansion remains unknown. We conceived and developed a fully deformable surface model for the comparison of pre-operative sac lumen size and final endobag size (measured using a follow-up scan) with the volume of injected polymer. Computed tomography images were acquired for eight patients. Aneurysms were manually and automatically segmented twice by the same observer. The injected polymer volume resulted 9% higher than the aneurysm pre-operative lumen size (p < 0.05), and 11% lower than the final follow-up endobag volume (p < 0.01). The automated method required minimal user interaction; it was fast and used a single set of parameters for all subjects. Intra-observer and manual vs. automated variability of measured volumes were 0.35 ± 2.11 and 0.07 ± 3.04 mL, respectively. Deformable surface models were used to quantify AAA size and showed that EVAS system devices tended to expand the sac lumen size.


Assuntos
Aneurisma da Aorta Abdominal , Procedimentos Endovasculares , Modelos Cardiovasculares , Tomografia Computadorizada por Raios X , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/fisiopatologia , Aneurisma da Aorta Abdominal/cirurgia , Procedimentos Endovasculares/instrumentação , Procedimentos Endovasculares/métodos , Humanos
17.
Artigo em Inglês | MEDLINE | ID: mdl-22463682

RESUMO

Automatic assessment of human femur morphology may provide useful clinical information with regard to hip and knee surgery, prosthesis design and management of hip instability. To this end, neck-shaft and anteversion angles are usually used. We propose a full automatic method to estimate these angles in human femurs. Multislice CT images from 18 dried bones were analysed. The algorithm fits 3D cylinders to different regions of the bone to estimate the angles. A manual segmentation and a conventional angle assessment were used for validation. We found anteversion angle as 20 ± 7° and neck-shaft angle as 130 ± 9°. Mean distances from femur surface to cylinders were 5.5 ± 0.6, 3.5 ± 0.6 and 2.4 ± 0.4 mm for condyles, diaphysis and neck regions, respectively. Automatic and conventional angles were positively correlated (r(2)>0.85). Manual and automatic segmentations did not differ. The method was fast and 100% reproducible. A robust in vivo segmentation algorithm should be integrated to advance towards a clinically compliant methodology.


Assuntos
Colo do Fêmur/diagnóstico por imagem , Fêmur/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Algoritmos , Diáfises/diagnóstico por imagem , Fêmur/anatomia & histologia , Colo do Fêmur/anatomia & histologia , Humanos
18.
Ann Biomed Eng ; 40(5): 1028-38, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22173558

RESUMO

An increasing number of intermediate risk asymptomatic subjects benefit from measures of atherosclerosis burden like coronary artery calcification studies with non-contrast heart computed tomography (CT). However, additional information can be derived from these studies, looking beyond the coronary arteries and without exposing the patients to further radiation. We report a semi-automatic method that objectively assesses ascending, arch and descending aorta dimension and shape from non-contrast CT datasets to investigate the effect of aging on thoracic aorta geometry. First, the segmentation process identifies the vessel centerline coordinates following a toroidal path for the curvilinear portion and axial planes for descending aorta. Then, reconstructing oblique planes orthogonal to the centerline direction, it iteratively fits circles inside the vessel cross-section. Finally, regional thoracic aorta dimensions (diameter, volume and length) and shape (vessel curvature and tortuosity) are calculated. A population of 200 normotensive men was recruited. Length, mean diameter and volume differed by 1.2 cm, 0.13 cm and 21 cm(3) per decade of life, respectively. Aortic shape uncoiled with aging, reducing its tortuosity and increasing its radius of curvature. The arch was the most affected segment. In conclusion, non-contrast cardiac CT imaging can be successfully employed to assess thoracic aorta 3D morphometry.


Assuntos
Envelhecimento/patologia , Aorta Torácica/diagnóstico por imagem , Angiografia Coronária , Vasos Coronários , Imageamento Tridimensional , Tomografia Computadorizada por Raios X , Humanos , Masculino
19.
Artigo em Inglês | MEDLINE | ID: mdl-23367047

RESUMO

Measures of atherosclerosis burden like coronary artery calcification are performed using non-contrast heart CT. However, additional information can be derived from these studies, looking beyond the coronary arteries without exposing the patients to further radiation. We present a semi-automated method to assess ascending, arch and descending aorta geometry from non-contrast CT datasets in 250 normotensive patients. We investigated the effect of aging on thoracic aorta morphometry. The algorithm identifies the aortic centerline coordinates following a toroidal path for the curvilinear portion and axial planes for descending aorta. Then it reconstructs oblique planes orthogonal to the centerline direction and a circle fitting process estimates the vessel cross-section. Finally, global thoracic aorta dimensions (diameter, volume and length) and shape (vessel curvature and tortuosity, aortic arch width and height) are calculated. From a multivariate analysis, adjusted for gender and body-size area, aortic volume and arch width were the descriptors that better represented the aortic size and shape alterations with aging. The thoracic aorta suffers an expanding and unfolding process with aging that deserves further attention to prevent aortic aneurisms.


Assuntos
Envelhecimento/fisiologia , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/fisiologia , Aortografia/métodos , Modelos Anatômicos , Modelos Cardiovasculares , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Simulação por Computador , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão/fisiologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
Artigo em Inglês | MEDLINE | ID: mdl-21095973

RESUMO

The value of mean arterial pressure (MBP) is of clinical importance, and is required for peripheral resistance calculation as well as for central blood pressure calibration procedures. MBP is usually estimated at the upper arm using systolic and diastolic sphygmomanometers pressure values, as 33% of pulse pressure (PP) above diastolic pressure. In a previous work, we proposed to use 38%. The aim of this study was to investigate the validity of the proposed formula to calculate MBP, when assessing subjects with a wide range of blood pressure and pulse wave velocity (PWV) levels. In 73 volunteers (56 ± 10 years, range: 27-82; pulse pressure: 59 ± 12 mmHg, range: 43-86; PWV: 10 ± 2 m/s, range: 8-17) arterial pressure waveforms were obtained at the left brachial artery by applanation tonometry. Diastolic (DBP) and systolic (SBP) brachial pressure were obtained with oscillometric device. Brachial-radial PWV was obtained at the same arm using mechano-transducers. MBP computed as 38% of PP above diastolic pressure, introduces an error of only 0.1% in brachial MBP estimation, independent of pressure and PWV levels.


Assuntos
Determinação da Pressão Arterial/métodos , Artéria Braquial/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Artéria Braquial/patologia , Calibragem , Feminino , Humanos , Masculino , Manometria/métodos , Pessoa de Meia-Idade , Oscilometria/métodos , Pressão , Reprodutibilidade dos Testes , Esfigmomanômetros
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