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1.
Clin Anat ; 36(4): 612-617, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36597994

RESUMO

Aortic valve fenestrations are defined as a loss of aortic valve leaflet tissue. They are a common but overlooked finding with unclear significance. The aim of this study was to investigate the varied functional anatomies of aortic valve fenestrations. A total of 400 formalin-fixed autopsied human hearts were macroscopically assessed and the function of the aortic valve of 16 reanimated human hearts were imaged using Visible Heart® methodologies. Aortic valve leaflet fenestrations were present in 43.0% of autopsied hearts (in one leaflet in 24.0%, in two leaflets 16.0%, in all leaflets 3.0%). Fenestrations were mostly present in left (25.5%) followed by right (23.3%) and noncoronary leaflet (16.3%). In 93.8% of cases, the fenestrations form clusters and were mainly located at the free edge of the leaflet in the commissural area (95.4%). Hearts with aortic valve fenestrations had significantly larger aortic valve diameters and aortic valve areas (p < 0.001). The average surface area sizes of fenestrations were 23.8 ± 16.6 mm2 , and the areas were largest for left followed by right and noncoronary leaflet fenestrations (p < 0.001). The fenestration areas positively correlated with donor age (r = 0.31; p = 0.02). Significant hypermobility and subjective weakening of the leaflet adhesion levels of the fenestrated regions were observed. In conclusion, fenestrations of the aortic leaflets are frequent, and their sizes may be significant. They occur in all age groups, yet their size increase with aging. Fragments of leaflets with fenestrations show different behaviors during the cardiac cycle versus unchanged areas.


Assuntos
Aorta , Valva Aórtica , Humanos , Valva Aórtica/anatomia & histologia , Envelhecimento , Autopsia
2.
Clin Anat ; 36(2): 234-241, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36193818

RESUMO

In this cadaver-based study, we aimed to present a novel approach to pulmonary valve (PV) anatomy, morphometry, and geometry to offer comprehensive information on PV structure. The 182 autopsied human hearts were investigated morphometrically. The largest PV area was seen for the coaptation center plane, followed by basal ring and the tubular plane (626.7 ± 191.7 mm2 vs. 433.9 ± 133.6 mm2 vs. 290.0 ± 110.1 mm2 , p < 0.001). In all leaflets, fenestrations are noted and occur in 12.5% of PVs. Only in 31.3% of PVs, the coaptation center is located in close vicinity of the PV geometric center. Similar-sized sinuses were found in 35.7% of hearts, in the remaining cases, significant heterogeneity was seen in size. The mean sinus depth was: left anterior 15.59 ± 2.91 mm, posterior: 16.04 ± 2.82 mm and right anterior sinus: 16.21 ± 2.81 mm and the mean sinus height: left anterior 15.24 ± 3.10 mm, posterior: 19.12 ± 3.79 mm and right anterior sinus: 18.59 ± 4.03 mm. For males, the mean pulmonary root perimeters and areas were significantly larger than those for females. Multiple forward stepwise regression model showed that anthropometric variables might predict the coaptation center plane (sex, age, and heart weight; R2  = 33.8%), tubular plane (sex, age, and BSA; R2  = 20.5%) and basal ring level area (heart weight and sex; R2  = 17.1%). In conclusion, the largest pulmonary root area is observed at the coaptation center plane, followed by the basal ring and tubular plane. The PV geometric center usually does not overlap valve coaptation center. Significant heterogeneity is observed in the size of sinuses and leaflets within and between valves. Anthropometric variables may be used to predict pulmonary root dimensions.


Assuntos
Valva Pulmonar , Masculino , Feminino , Humanos , Valva Pulmonar/anatomia & histologia , Cadáver , Autopsia , Tórax , Valva Aórtica/anatomia & histologia
3.
J Thorac Cardiovasc Surg ; 165(4): 1335-1342.e2, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-33985805

RESUMO

OBJECTIVE: During the last decade, special concerns have been raised about the anatomic relationships among the sinotubular junction, ventricular-aortic junction, and virtual basal ring to improve the results of root reconstruction. The aim of this study is to evaluate the in vivo anatomy of the aortic root after reimplantation with the Valsalva graft and the anatomic relationship between its components. METHODS: We analyzed 10 consecutive patients with tricuspid aortic valves who underwent reimplantation with the Valsalva graft between September and December 2019. Surgical clips were applied as markers at the level of proximal annular knots and at the distal reimplanted commissures on the neo-sinotubular junction. Electrocardiogram-gated computed tomography scan of the aortic root was performed. Coordinates of the markers were exported on a 3-dimensional modeling software, and the distances between the virtual basal ring and the Dacron graft basal landmarks were measured. RESULTS: The mean heights of Dacron graft basal landmarks from virtual basal ring were right-left commissure 7.1 ± 5.1 mm; right sinus 4.7 ± 4.1 mm; right-noncoronary commissure 2.8 ± 2.2 mm; noncoronary sinus 1.4 ± 1.6 mm; left-noncoronary commissure 2.2 ± 2.3 mm; and left sinus 2.0 ± 0.9 mm. The mean planar distances of basal Dacron graft landmarks from virtual basal ring (thickness) were right-left commissure 5.3 ± 3.1 mm; right sinus 2.8 ± 1.4 mm; right-noncoronary commissure 2.2 ± 1.5 mm; noncoronary sinus 1.5 ± 1.5 mm; left-noncoronary commissure 1.3 ± 1.0 mm; and left sinus 3.4 ± 2.5 mm. CONCLUSIONS: After reimplantation, despite a complete dissection of the root, slight asymmetry of graft proximal seating exists. The inner annuloplasty is on the virtual basal ring, and the proximal edge of the Dacron graft is on the ventricular-aortic junction at a slightly different thickness and height along the annular circumference. At the level of the right sinus and left/right commissure, the Dacron graft is higher than the virtual basal ring and the relative wall thickness is increased. The annular stabilization is unaffected.


Assuntos
Insuficiência da Valva Aórtica , Valva Aórtica , Humanos , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Valva Aórtica/anatomia & histologia , Aorta Torácica , Polietilenotereftalatos , Aorta/diagnóstico por imagem , Aorta/cirurgia , Reimplante , Insuficiência da Valva Aórtica/diagnóstico por imagem , Insuficiência da Valva Aórtica/cirurgia
4.
Anat Histol Embryol ; 51(5): 658-665, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35894158

RESUMO

The position of the coronary ostia was investigated in 70 segments of the aorta from young adult crossbred horses. After fixation with a 4% buffered aqueous formaldehyde solution and cautious dissection of the aortic bulb, the morphometric relationships between the coronary ostium and the aortic valvar elements were digitally analysed with the support of Image-Pro Plus® software. In horses, the left coronary ostium was near to the right valvular commissure in all cases (100%) analysed in this study. The left coronary ostium was at the level of the intercommissural line in 57.1% and below it in 42.9%. The right coronary ostium was near to the left valvular commissure in 58.6% (2.14 ± 0.32 cm) and close to the right valvular commissure in 41.4% (2.27 ± 0.40 cm). Concerning the intercommissural line, the right coronary ostia was at its level in 24.3% and below it in 75.7%. Accessory coronary ostia were observed in 8.6% of the specimens. In view of the results, it was possible to assume that the positions of the coronary ostia in equines tend towards a standard morphological disposition. Thus, perfusion of the left coronary artery occurs partly more frequently in ventricular systole and complete perfusion occurs less frequently in ventricular diastole. For the right coronary artery, perfusion is mostly complete in diastole and partially in ventricular systole.


Assuntos
Aorta/anatomia & histologia , Valva Aórtica/anatomia & histologia , Vasos Coronários/anatomia & histologia , Cavalos/anatomia & histologia , Animais , Diástole , Dissecação/veterinária , Formaldeído , Sístole
6.
Anat Histol Embryol ; 51(3): 339-346, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35165926

RESUMO

The aortic valve was investigated in 58 sheep and 60 swine without heart disease. After fixation in 4% formalin, the distance between the ostia and the elements of the right/left aortic sinuses was measured. For the left coronary ostium (LCO), it was found that in sheep 81% were below and 19% at the level of intercomissural line (IL). In pigs, 88.3% were below and 11.7% at the IL level. In sheep, the OCL was close to the right valve commissure (CVR) in 98.3% and close to the left valve commissure (CVV) in 1.7%. In pigs, it was close to RVC at 83.3% and close to LVC at 16.7%. Regarding to RCO, it was found that in sheep 69% was below, 1.7% was above and 29.3% at the IL level. In pigs, 20% were below, 15% above and 65% at the IL level. The distance of the RCO in relation to the valve commissures was 56.9% close to LVC and 43.1% close to RVC in sheep. In pigs, 81.7% were close to LVC and 18.3% close to RVC. The position of LCO was balanced between sheep and swine, while the RCO in swine was closer to CVE when compared with sheep. The accessory coronary ostium was observed in 18.6% of sheep and 10% of pigs. Thus, it is concluded that in sheep and swine the left coronary artery is perfused only in ventricular diastole. Perfusion of the right coronary artery occurs more frequently in diastole and less frequently in ventricular systole.


Assuntos
Valva Aórtica , Vasos Coronários , Animais , Valva Aórtica/anatomia & histologia , Vasos Coronários/anatomia & histologia , Ovinos , Suínos
7.
Rheumatol Int ; 42(4): 683-688, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34729637

RESUMO

To assess the association between the aortic root diameter in HLA-B27 positive (+) and HLA-B27 negative (-) ankylosing spondylitis (AS) patients from the CARDAS cohort. The CARDAS study is a cross-sectional study in AS patients between 50 and 75 years who were recruited from a large rheumatology outpatient clinic. Patients underwent cardiovascular screening including echocardiography, with 2D, spectral, and color flow Doppler measurements. The aortic root was measured at sinuses of Valsalva during diastole. The aortic root diameter was adjusted for body surface area (BSA) (aortic root index, cm/m2). 193 Consecutive AS patients were included of whom 158 (82%) were HLA-B27 positive. The aortic root index was significantly higher in HLA-B27 + patients compared to HLA-B27- patients, respectively, 1.76 cm ± 0.21 vs. 1.64 cm ± 0.14, p < 0.001. No difference was seen in the prevalence of aortic valve regurgitation (AVR), p = 0.8. Regression analysis showed a significant association between HLA-B27 and aortic root index corrected for age, sex and cardiovascular risk factors (ß 0.091, 95% CI 0.015-0.168, p = 0.02). Especially, male HLA-B27 + patients had a significantly increased aortic root index compared to male HLA-B27- AS patients, respectively, 1.76 cm (1.63-1.88) and 1.59 cm (1.53-1.68), p < 0.001. We found an increased aortic root index in elderly HLA-B27 + AS patients compared to HLA-B27- AS patients, especially in male patients. No difference was seen in the prevalence of AVR. However, as AVR can be progressive, echocardiographic monitoring in elderly male HLA-B27 + AS might be considered.


Assuntos
Valva Aórtica , Antígeno HLA-B27 , Espondilite Anquilosante , Idoso , Valva Aórtica/anatomia & histologia , Valva Aórtica/diagnóstico por imagem , Estudos de Coortes , Estudos Transversais , Antígeno HLA-B27/genética , Humanos , Masculino , Espondilite Anquilosante/diagnóstico
8.
Am J Cardiol ; 164: 118-122, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34815057

RESUMO

Supravalvar aortic stenosis (SVAS) severity guides management, including decisions for surgery. Physiologic and technical factors limit the determination of SVAS severity by Doppler echocardiography and cardiac catheterization in Williams syndrome (WS). We hypothesized SVAS severity could be determined by the sinotubular junction-to-aortic annulus ratio (STJ:An). We reviewed all preintervention echocardiograms in patients with WS with SVAS cared for at our center. We measured STJ, An, peak and mean Doppler gradients, and calculated STJ:An. We created 2 mean gradient prediction models. Model 1 used the simplified Bernoulli's equation, and model 2 used computational fluid dynamics (CFD). We compared STJ:An to Doppler-derived and CFD gradients. We reviewed catheterization gradients and the waveforms and analyzed gradient variability. We analyzed 168 echocardiograms in 54 children (58% male, median age at scan 1.2 years, interquartile range [IQR] 0.5 to 3.6, median echocardiograms 2, IQR 1 to 4). Median SVAS peak Doppler gradient was 24 mm Hg (IQR 14 to 46.5). Median SVAS mean Doppler gradient was 11 mm Hg (IQR 6 to 21). Median STJ:An was 0.76 (IQR 0.63 to 0.84). Model 1 underpredicted clinical gradients. Model 2 correlated well with STJ:An through all severity ranges and demonstrated increased pressure recovery distance with decreased STJ:An. The median potential variability in catheterization-derived gradients in a given patient was 14.5 mm Hg (IQR 7.5 to 19.3). SVAS severity in WS can be accurately assessed using STJ:An. CFD predicts clinical data well through all SVAS severity levels. STJ:An is independent of physiologic state and has fewer technical limitations than Doppler echocardiography and catheterization. STJ:An could augment traditional methods in guiding surgical management decisions.


Assuntos
Aorta/diagnóstico por imagem , Estenose Aórtica Supravalvular/diagnóstico por imagem , Valva Aórtica/diagnóstico por imagem , Seio Aórtico/diagnóstico por imagem , Aorta/anatomia & histologia , Estenose Aórtica Supravalvular/congênito , Estenose Aórtica Supravalvular/etiologia , Estenose Aórtica Supravalvular/fisiopatologia , Valva Aórtica/anatomia & histologia , Pré-Escolar , Ecocardiografia , Ecocardiografia Doppler , Feminino , Humanos , Lactente , Masculino , Índice de Gravidade de Doença , Seio Aórtico/anatomia & histologia , Síndrome de Williams/complicações
9.
Am J Cardiol ; 164: 111-117, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34844737

RESUMO

Patients presenting with severe aortic stenosis and large aortic annuli are challenging to treat because of the size limitations of available transcatheter heart valves. In this study, we aimed to determine clinical and hemodynamic outcomes in patients presenting with large aortic annuli who underwent transcatheter aortic valve implantation (TAVI). Patients from the German Aortic Valve Registry who underwent TAVI either with the Edwards Sapien (ES) or Medtronic CoreValve (MCV) systems from 2011 to 2017 were included. They were further stratified into a large (aortic annulus diameter 26 to 29 mm for ES; 26 to 30 mm for MCV) and extra-large (aortic annulus diameter >29 mm for ES; >30 mm for MCV) group and analyzed using propensity score adjustment. Extra-large was set beyond the sizing limitations according to the manufacturer's instructions for use. Patients in the large (n = 5,628) and extra-large (n = 509) groups were predominantly male (large: 92.6% vs extra-large: 91.9%). The 30-day mortality was comparable (large: 3.9% vs extra-large: 5.0%, p = 0.458). Procedure duration (large: 78.9 minutes ± 0.82 vs extra-large: 86.4 minutes ± 1.9, p <0.001) was longer in the extra-large group. Likewise, vascular complications (large: 6.2% vs extra-large: 12%, p = 0.002) and the need for a permanent pacemaker implantation (large: 18.8% vs extra-large: 26.0%, p = 0.027) were more often present in the extra-large group. Aortic regurgitation ≥II after valve implantation was numerically higher (large: 3.0% vs extra-large: 5.3%, p = 0.082) in patients with extra-large anatomy. In conclusion, patients with large and extra-large aortic annulus diameters who underwent TAVI have comparable 30-day mortality. Beyond the recommended annulus range, there is a higher risk for vascular complications and permanent pacemaker implantation.


Assuntos
Insuficiência da Valva Aórtica/epidemiologia , Estenose da Valva Aórtica/cirurgia , Valva Aórtica/anatomia & histologia , Arritmias Cardíacas/epidemiologia , Mortalidade , Complicações Pós-Operatórias/epidemiologia , Substituição da Valva Aórtica Transcateter , Idoso , Idoso de 80 Anos ou mais , Arritmias Cardíacas/terapia , Estimulação Cardíaca Artificial/estatística & dados numéricos , Feminino , Alemanha , Próteses Valvulares Cardíacas , Humanos , Masculino , Tamanho do Órgão , Ajuste de Prótese , Sistema de Registros , Índice de Gravidade de Doença , Doenças Vasculares/epidemiologia
11.
Rev. chil. cardiol ; 40(3): 241-244, dic. 2021. ilus
Artigo em Espanhol | LILACS | ID: biblio-1388102

RESUMO

Resumen: La válvula aórtica es una estructura más compleja de lo que hasta hace poco se estimaba y en la actualidad se considera a esta una estructura más de la "Raíz Aórtica", cuyos componentes se describen en el presente "Artículo Especial". Lo anterior ha alcanzado mayor importancia con el desarrollo de los procedimientos quirúrgicos que permiten preservar la válvula aórtica en la insuficiencia aórtica, pero, muy especialmente, para el tratamiento percutáneo de la estenosis aórtica, de la cual se reconocen, a su vez, tres formas principales, que también se describen en el presente artículo.


Abstract: The aortic valve is a more complex structure than has been estimated until recently and is now considered to be just another structure of the "Aortic Root", the components of which are described in this "Special Feature". This has become more important with the development of surgical procedures that allow preservation of the aortic valve in aortic insufficiency, but especially for the percutaneous treatment of aortic stenosis, of which three main forms are recognized, which are also described in this article.


Assuntos
Humanos , Adulto , Valva Aórtica/anatomia & histologia , Estenose da Valva Aórtica/cirurgia , Implante de Prótese de Valva Cardíaca/métodos
12.
Biomech Model Mechanobiol ; 20(6): 2413-2435, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34549354

RESUMO

This paper presents a new method for modeling the mechanics of the aortic valve and simulates its interaction with blood. As much as possible, the model construction is based on first principles, but such that the model is consistent with experimental observations. We require that tension in the leaflets must support a pressure, then derive a system of partial differential equations governing its mechanical equilibrium. The solution to these differential equations is referred to as the predicted loaded configuration; it includes the loaded leaflet geometry, fiber orientations and tensions needed to support the prescribed load. From this configuration, we derive a reference configuration and constitutive law. In fluid-structure interaction simulations with the immersed boundary method, the model seals reliably under physiological pressures and opens freely over multiple cardiac cycles. Further, model closure is robust to extreme hypo- and hypertensive pressures. Then, exploiting the unique features of this model construction, we conduct experiments on reference configurations, constitutive laws and gross morphology. These experiments suggest the following conclusions: (1) The loaded geometry, tensions and tangent moduli primarily determine model function. (2) Alterations to the reference configuration have little effect if the predicted loaded configuration is identical. (3) The leaflets must have sufficiently nonlinear material response to function over a variety of pressures. (4) Valve performance is highly sensitive to free edge length and leaflet height. These conclusions suggest appropriate gross morphology and material properties for the design of prosthetic aortic valves. In future studies, our aortic valve modeling framework can be used with patient-specific models of vascular or cardiac flow.


Assuntos
Valva Aórtica/anatomia & histologia , Valva Aórtica/fisiologia , Modelos Cardiovasculares , Desenho de Prótese , Reologia , Simulação por Computador , Humanos , Pressão
13.
Exp Biol Med (Maywood) ; 246(21): 2278-2289, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34260291

RESUMO

Valvular endothelial cells line the outer layer of heart valves and can withstand shear forces caused by blood flow. In contrast to vascular endothelial cells, there is limited amount of research over valvular endothelial cells. For this reason, the exact physiologic behavior of valvular endothelial cells is unclear. Prior studies have concluded that valvular endothelial cells align perpendicularly to the direction of blood flow, while vascular endothelial cells align parallel to blood flow. Other studies have suggested that different ranges of shear stress uniquely impact the behavior of valvular endothelial cells. The goal of this study was to characterize the response of valvular endothelial cell under different types, magnitudes, and durations of shear stress. In this work, the results demonstrated that with increased shear rate and duration of exposure, valvular endothelial cells no longer possessed the traditional cuboidal morphology. Instead through the change in cell circularity and aspect ratio, valvular endothelial cells aligned in an organized manner. In addition, different forms of shear exposure caused the area and circularity of valvular endothelial cells to decrease while inducing mesenchymal transformation validated through αSMA and TGFß1 expression. This is the first investigation showing that valvular endothelial cells alignment is not as straightforward as once thought (perpendicular to flow). Different types and magnitudes of shear induce different local behaviors. This is also the first demonstration of valvular endothelial cells undergoing EndMT without chemical inducers on a soft surface in vitro. Findings from this study provide insights to understanding the pathophysiology of valvular endothelial cells which can potentially propel future artificial engineered heart valves.


Assuntos
Valva Aórtica/citologia , Diferenciação Celular/fisiologia , Células Endoteliais/citologia , Resistência ao Cisalhamento/fisiologia , Animais , Valva Aórtica/anatomia & histologia , Valva Aórtica/fisiologia , Células Endoteliais/fisiologia , Endotélio Vascular/citologia , Endotélio Vascular/fisiologia , Imunofluorescência , Suínos
14.
Circ Res ; 128(9): 1330-1343, 2021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-33914609

RESUMO

Aortic stenosis (AS) remains one of the most common forms of valve disease, with significant impact on patient survival. The disease is characterized by left ventricular outflow obstruction and encompasses a series of stenotic lesions starting from the left ventricular outflow tract to the descending aorta. Obstructions may be subvalvar, valvar, or supravalvar and can be present at birth (congenital) or acquired later in life. Bicuspid aortic valve, whereby the aortic valve forms with two instead of three cusps, is the most common cause of AS in younger patients due to primary anatomic narrowing of the valve. In addition, the secondary onset of premature calcification, likely induced by altered hemodynamics, further obstructs left ventricular outflow in bicuspid aortic valve patients. In adults, degenerative AS involves progressive calcification of an anatomically normal, tricuspid aortic valve and is attributed to lifelong exposure to multifactoral risk factors and physiological wear-and-tear that negatively impacts valve structure-function relationships. AS continues to be the most frequent valvular disease that requires intervention, and aortic valve replacement is the standard treatment for patients with severe or symptomatic AS. While the positive impacts of surgical interventions are well documented, the financial burden, the potential need for repeated procedures, and operative risks are substantial. In addition, the clinical management of asymptomatic patients remains controversial. Therefore, there is a critical need to develop alternative approaches to prevent the progression of left ventricular outflow obstruction, especially in valvar lesions. This review summarizes our current understandings of AS cause; beginning with developmental origins of congenital valve disease, and leading into the multifactorial nature of AS in the adult population.


Assuntos
Estenose da Valva Aórtica/etiologia , Fatores Etários , Animais , Valva Aórtica/anormalidades , Valva Aórtica/anatomia & histologia , Valva Aórtica/fisiopatologia , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/genética , Estenose da Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/cirurgia , Calcinose/etiologia , Progressão da Doença , Humanos , Ilustração Médica , Camundongos , Fatores de Risco , Obstrução do Fluxo Ventricular Externo/etiologia , Obstrução do Fluxo Ventricular Externo/prevenção & controle
15.
Clin Radiol ; 76(1): 15-26, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32446601

RESUMO

Aortic stenosis is the most prevalent valvular heart disease worldwide, and rates are increasing with the growing and more elderly population. Although the precise mechanisms that underpin aortic valve stenosis are incompletely understood, pathological valvular calcification has emerged as a key instigator in mediating the biomechanical stiffening that can lead to symptoms, the need for aortic valve replacement, and death if left untreated. Here, we review the currently understood processes leading to aortic valve calcification, summarise the contemporary imaging assessments of valve calcification, and highlight how these might improve patient care and accelerate our pathological understanding and the development of an effective medical therapy.


Assuntos
Estenose da Valva Aórtica/diagnóstico por imagem , Valva Aórtica/patologia , Calcinose/diagnóstico por imagem , Valva Aórtica/anatomia & histologia , Valva Aórtica/diagnóstico por imagem , Ecocardiografia , Humanos , Imageamento Tridimensional , Imagem Cinética por Ressonância Magnética , Microscopia Eletrônica , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X
16.
J Thorac Cardiovasc Surg ; 161(2): 581-590.e6, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-31879167

RESUMO

BACKGROUND: This study examined whether the presence of a sinus of Valsalva equivalent in the KONECT RESILIA aortic valved conduit (Edwards Lifesciences, Irvine, Calif) improves valve hemodynamics, kinematics, and performance. METHODS: A 28-mm KONECT RESILIA aortic valved conduit was used to create an in vitro flow test model, and the same aortic valved conduit model without a sinus section was used as a control. Particle image velocimetry and hydrodynamic characterization experiments were conducted in the vicinity of the valves in a validated left-heart simulator at 3 cardiac output levels. In addition, leaflet kinematics of the valves were determined through en face high-speed imaging. RESULTS: The KONECT RESILIA aortic valved conduit model exhibited lower mean and peak transvalvular pressure gradients than the control model at all 3 cardiac outputs. In addition, its leaflets opened more fully than did those of the valved conduit without the sinuses, yielding greater effective and geometric orifice areas. It was found that the presence of the sinuses not only facilitated the development of larger and more stable vortices at the initial stages of the cardiac cycle but also helped to maintain these vortices during the late stages of the cardiac cycle, leading to smoother valve closure. CONCLUSIONS: The KONECT RESILIA aortic valved conduit reproduces the bulged section of the aortic root corresponding to the sinuses of Valsalva. With this Valsalva-type conduit, larger orifice areas were observed, improving valve hemodynamics that may enhance performance.


Assuntos
Valva Aórtica/cirurgia , Próteses Valvulares Cardíacas , Aorta/anatomia & histologia , Aorta/fisiologia , Aorta/cirurgia , Valva Aórtica/anatomia & histologia , Valva Aórtica/fisiologia , Fenômenos Biomecânicos , Velocidade do Fluxo Sanguíneo , Prótese Vascular/normas , Próteses Valvulares Cardíacas/normas , Hemodinâmica , Humanos , Técnicas In Vitro , Seio Aórtico/anatomia & histologia , Seio Aórtico/fisiologia
17.
Acta Cardiol ; 76(4): 335-348, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32602774

RESUMO

Aortic valve stenosis is a degenerative disease affecting increasing number of individuals and characterised by thickening, calcification and fibrosis of the valve resulting in restricted valve motion. Degeneration of the aortic valve is no longer considered a passive deposition of calcium, but an active process that involves certain mechanisms, that is endothelial dysfunction, inflammation, increased oxidative stress, calcification, bone formation, lipid deposition, extracellular matrix (ECM) remodelling and neoangiogenesis. Accumulating evidence indicates an important role for neoangiogenesis (i.e. formation of new vessels) in the pathogenesis of aortic valve stenosis. The normal aortic valve is generally an avascular tissue supplied with oxygen and nutrients via diffusion from the circulating blood. In contrast, presence of intrinsic micro-vasculature has been demonstrated in stenotic and calcified valves. Importantly, presence and density of neovessels have been associated with inflammation, calcification and bone formation. It remains unclear whether neoangiogenesis is a compensatory mechanism aiming to counteract hypoxia and increased metabolic demands of the thickened tissue or represents an active contributor to disease progression. Data extracted mainly from animal studies are supportive of a direct detrimental effect of neoangiogenesis, however, robust evidence from human studies is lacking. Thus, there is inadequate knowledge to assess whether neoangiogenesis could serve as a future therapeutic target for a disease that no effective medical therapy exists. In this review, we present basic aspects of anatomy and structure of the normal and stenotic aortic valve and we focus on the role of valve vasculature in the natural course of valve calcification and stenosis.


Assuntos
Estenose da Valva Aórtica , Valva Aórtica , Calcinose , Valva Aórtica/anatomia & histologia , Valva Aórtica/patologia , Estenose da Valva Aórtica/patologia , Calcinose/patologia , Fibrose , Humanos , Inflamação
18.
Am J Perinatol ; 38(14): 1480-1482, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-32604447

RESUMO

OBJECTIVE: This study aimed to compare left ventricular outflow tract (LVOT) diameter measurements using two-dimensional (2D) echocardiography at the sino-tubular junction (STJ) and at the aortic valve (AV) hinges in newborn infants. STUDY DESIGN: This is a retrospective study in a tertiary neonatal unit where infants underwent echocardiography for evaluation of murmur or as part of cardiovascular assessment. Three consecutive cardiac cycles were chosen to measure the LVOT diameter in end systole at the STJ and at the AV hinges. Bias and levels of agreement were examined using Bland-Altman plot. Intraobserver variability was examined using intraclass correlation. RESULTS: A total of 366 measurements were obtained from 61 infants with a mean (standard deviation) gestation and birth weight of 33.4 (6.9) weeks and 2,181 (1369) g, respectively. There was good correlation between the LVOT diameter measurements using the STJ and AV hinges (r = 0.958, p < 0.001). The mean (standard deviation and 95% confidence interval) bias between LVOT diameter measurements using STJ and AV hinges were 0.93 (0.45 and 0.06-1.81) mm. There was good intraobserver variability between the measurements using both methods. CONCLUSION: Using 2D echocardiography, LVOT measurements using the STJ tend to be higher when compared with LVOT measurements using the AV hinges. KEY POINTS: · Echocardiographic assessment of left ventricular output is undertaken frequently.. · Left ventricular outflow tract can be measured at the aortic valve hinges, sinus of valsalva, or sino-tubular junction.. · Left ventricular outflow tract measured at the sino-tubular junction tends to higher when compared with aortic valve.


Assuntos
Valva Aórtica/anatomia & histologia , Ecocardiografia , Ventrículos do Coração/diagnóstico por imagem , Valva Aórtica/diagnóstico por imagem , Débito Cardíaco , Ventrículos do Coração/anatomia & histologia , Humanos , Lactente , Recém-Nascido , Estudos Retrospectivos , Função Ventricular
19.
Interact Cardiovasc Thorac Surg ; 32(2): 196-203, 2021 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-33236042

RESUMO

OBJECTIVES: This study aimed to compare the effect of surgical aortic valve replacement (SAVR) on coronary height in patients undergoing SAVR with rapid-deployment or SAVR with several standard sutured bioprostheses. This study may identify patients at higher risk of coronary obstruction during valve-in-valve procedures. METHODS: We analysed 112 patients [mean age 71 (9 SD) years] who underwent SAVR with either a rapid-deployment aortic bioprosthesis (EDWARDS INTUITY Elite Valve) or other standard sutured biological valves. The coronary heights were assessed by computed tomography scan with the Philips 3D HeartNavigator system. RESULTS: Two groups of patients were analysed: 51 (45.5%) patients implanted with an RD-AVR, which is a supra-annular valve that requires 3 anchoring sutures without the use of pledgets, and 61 (54.5%) patients implanted with a conventional supra-annular sutured bioprosthesis. The mean right and left coronary artery-to-annulus (RCAA and LCAA) heights at baseline were 16.9 (4.6 SD) and 14.2 (4.0 SD) mm in the standard sutured group and 16.3 (3.5 SD) and 12.8 (2.9 SD) mm in the RD-AVR group, respectively; a significantly shorter distance was observed for the left coronary artery in the rapid-deployment group (P = 0.420 for RCAA height and P = 0.044 for LCAA). Postoperatively, the mean RCAA and LCAA heights were significantly decreased in both groups compared to baseline. A mean of 11.5 (4.8 SD) mm for the RCAA and 7.9 (4.3 SD) mm for the LCAA in the standard sutured group as well as 14.4 (3.9 SD) mm for the RCAA and 9.0 (3.1 SD) mm for the LCAA in the RD-AVR group were observed (P < 0.001 for RCAA and LCAA in both the sutured and rapid-deployment groups). Despite the significant difference in the mean distance from the left coronary artery to annulus between the groups at baseline, the postoperative mean distance of the LCAA to the sewing ring was still higher in the RD-AVR group. CONCLUSIONS: A significantly shorter coronary artery-to-aortic annulus distance for both the right and left main coronary arteries was observed after AVR with different conventional sutured supra-annular bioprostheses compared to AVR with rapid-deployment valves. These findings might be relevant for bioprosthesis selection, especially for young patients.


Assuntos
Aorta/anatomia & histologia , Valva Aórtica/cirurgia , Vasos Coronários/anatomia & histologia , Implante de Prótese de Valva Cardíaca/métodos , Idoso , Idoso de 80 Anos ou mais , Valva Aórtica/anatomia & histologia , Estenose da Valva Aórtica/cirurgia , Bioprótese , Próteses Valvulares Cardíacas , Humanos , Masculino , Período Pós-Operatório , Fatores de Tempo
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