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1.
Echocardiography ; 36(6): 1145-1152, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31025771

RESUMO

OBJECTIVES: This study aims to analyze the variability between two trained neonatologists when performing consecutive echocardiograms using tissue Doppler imaging (TDI) and conventional methods in very low birth weight infant (VLBWI). METHODS: Two serial echocardiograms were performed in 30 VLBWI infants. The echocardiographic parameters analyzed were tricuspid annular plane systolic excursion (TAPSE), A', E', and S' waves, and myocardial performance index acquired by TDI (MPI-TDI) of both ventricles and shortening fraction (SF). The intra-observer and inter-observer agreements and the intra-operator agreement were analyzed using quantitative and qualitative statistical methods. RESULTS: The intra-observer agreement was very good, TAPSE, and TDI-derived parameters had an intra-class correlation (ICC) > 0.8. TDI-derived velocities had a coefficient of variation (COV) < 11%, while MPI-TDI had a COV between 20%-28%. The inter-observer agreement was excellent. There was greater variability when analyzing intra-operator agreement, with the least variable parameter being TAPSE. According to PABAK, the variability presented moderately substantial agreement. CONCLUSIONS: Tricuspid annular plane systolic excursion is very reproducible between observers and operators. Measurements of TDI wave velocities are more reproducible than MPI-TDI. TDI is sufficiently reproducible in the VLBWI if adequate training is performed, and guidelines are followed to obtain standardized echocardiographic images.


Assuntos
Ecocardiografia Doppler/métodos , Recém-Nascido de muito Baixo Peso/fisiologia , Valva Tricúspide/fisiologia , Função Ventricular/fisiologia , Ventrículos do Coração/fisiopatologia , Humanos , Recém-Nascido , Variações Dependentes do Observador , Estudos Prospectivos , Reprodutibilidade dos Testes
2.
Ann Biomed Eng ; 47(6): 1422-1434, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30859434

RESUMO

Computational modeling can be used to improve understanding of tricuspid valve (TV) biomechanics and supplement knowledge gained from benchtop and large animal experiments. The aim of this study was to develop a computational model of the TV using high resolution micro-computed tomography (µCT) imaging and fluid-structure interaction simulations. A three-dimensional TV model, incorporating detailed leaflet and chordal geometries, was reconstructed from µCT images of an excised porcine TV obtained under diastolic conditions. The leaflets were described using non-linear stress-strain relations and chordal properties were iteratively adjusted until valve closure was obtained. The leaflet coaptation zone obtained from simulation of valve closure was validated against µCT images of the TV captured at peak systole. The computational model was then used to simulate a regurgitant TV morphology and investigate changes in closure dynamics. Overall, the mean stresses in the leaflet belly region and the chordae tendinae of the regurgitant TV were 7% and 3% higher than the same regions of the normal TV. The maximum principal strain in the leaflet belly of the regurgitant TV was also 9% higher than the same regions of the normal TV. It is anticipated that this computational model can be used in future studies for further understanding of TV biomechanics and associated percutaneous repairs.


Assuntos
Modelos Cardiovasculares , Valva Tricúspide/fisiologia , Animais , Simulação por Computador , Análise de Elementos Finitos , Suínos , Valva Tricúspide/diagnóstico por imagem , Microtomografia por Raio-X
3.
JACC Cardiovasc Imaging ; 12(3): 458-468, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30846121

RESUMO

An appreciation of the complex and variable anatomy of the tricuspid valve is essential to unraveling the pathophysiology of tricuspid regurgitation. A greater appreciation of normal and abnormal anatomy is important as new methods of treating the tricuspid regurgitation are developed. This review of tricuspid valve and right heart anatomy is followed by a discussion of the possible pathophysiology of secondary (functional) tricuspid regurgitation.


Assuntos
Hemodinâmica , Insuficiência da Valva Tricúspide/fisiopatologia , Valva Tricúspide/anatomia & histologia , Valva Tricúspide/fisiologia , Função Ventricular Direita , Humanos , Fatores de Risco , Valva Tricúspide/diagnóstico por imagem , Insuficiência da Valva Tricúspide/diagnóstico por imagem , Insuficiência da Valva Tricúspide/etiologia
4.
JACC Cardiovasc Interv ; 12(2): 169-178, 2019 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-30678795

RESUMO

OBJECTIVES: The authors aimed to comprehensively detail the right atrioventricular valve functional leaflet anatomies. BACKGROUND: The rapid development of both surgical and percutaneous repair techniques for tricuspid regurgitation has renewed interest in variations in the morphology of the right atrioventricular valve. METHODS: The functioning right atrioventricular valves of 40 reanimated human hearts were imaged using Visible Heart methodologies. Hearts were then perfusion-fixed and dissected, uniquely allowing for the comparative assessments of functional versus fixed valve anatomies from the same set of donor hearts. RESULTS: The right atrioventricular valves have "3-leaflet" configurations in 57.5% and "4-leaflet" configurations in the remaining hearts. For 4-leaflet valves, extra leaflets were commonly observed in the most inferior regions of the annuli. No difference in valve perimeters between 2 valve types were observed (112.2 vs. 117.1 mm; p = 0.14). In 3-leaflet valves, septal, mural, and superior leaflets occupied 32.2 ± 6.5%, 15.9 ± 5.5%, and 25.5 ± 6.2% of the annulus, respectively, whereas in the 4-leaflet arrangements, these values were 27.0 ± 5.8% (septal), 12.0 ± 4.5% (inferior), 13.7 ± 9.4% (mural), and 19.8 ± 6.1% (superior). The muroseptal/inferoseptal commissures were usually located in the cavotricuspid regions, whereas the inferomural and superomural commissures were in the right atrial appendage vestibule area. CONCLUSIONS: The right atrioventricular valve has 4 functional leaflets in more than 40% of cases. The authors found that the inferomural region is the most variable area of the valve and believe that anatomic variation is an important consideration for planned interventions.


Assuntos
Cateterismo Cardíaco , Insuficiência da Valva Tricúspide/cirurgia , Valva Tricúspide/anatomia & histologia , Adulto , Idoso , Dissecação , Endoscopia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valva Tricúspide/fisiologia , Insuficiência da Valva Tricúspide/patologia , Insuficiência da Valva Tricúspide/fisiopatologia , Gravação em Vídeo
5.
J Thorac Cardiovasc Surg ; 157(4): 1452-1461.e1, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30392947

RESUMO

OBJECTIVES: Surgical correction of functional tricuspid regurgitation is focused on prosthetic reduction and remodeling of the tricuspid annulus. We set out to investigate the precise geometry of the human tricuspid annulus to better guide surgical therapy. METHODS: Eleven human donor hearts with normal right ventricular function and without tricuspid regurgitation that were rejected for clinical transplantation were harvested. Sonomicrometry crystals were sewn around the tricuspid annulus and pressure sensors placed in the right ventricle and right atrium. The hearts were studied in the TransMedics Organ Care System (Andover, Mass) ex vivo perfusion apparatus in the right heart working model. Data were acquired at baseline and before and after bolus calcium infusion. Annular height, dimensions, strain, and curvature were calculated based on 3-dimensional crystal coordinates. RESULTS: Maximal annular area was 997 ± 258 mm2 and minimal 902 ± 257 mm2 with contraction of 10% ± 5% at baseline and 19% ± 6% after calcium (P = .007). Segmental contractility of anterior, posterior, and septal annular regions was 7% ± 5%, 6% ± 4%, and 6% ± 3%, respectively. Only anterior region had increased contractility after calcium infusion (to 15% ± 5%; P = .023). Annulus had its high points at anteroseptal commissure and the midposterior region and lowest point in the midseptal region with maximal and minimal height of 5.0 ± 1.1 mm and 4.0 ± 1.1 mm, respectively. The greatest curvature responsible for out of plane annular bending was observed at annular high points. CONCLUSIONS: The human tricuspid annulus is a complex 3-dimensional dynamic structure with its high points and maximal degree of bending at the anteroseptal commissure and midposterior annulus. These detailed geometric data may aid the design of more physiologic annular prostheses and surgical reparative techniques.


Assuntos
Ecocardiografia , Valva Tricúspide/diagnóstico por imagem , Adulto , Fenômenos Biomecânicos , Ecocardiografia/instrumentação , Feminino , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Transdutores de Pressão , Valva Tricúspide/fisiologia
6.
J Cardiothorac Vasc Anesth ; 33(3): 717-724, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30583929

RESUMO

OBJECTIVE: To assess the agreement between 2-dimensional tricuspid annular plane systolic excursion (2D-TAPSE), 2D-TAPSE-apex, and 2D speckle tracking echocardiography (STE-TAPSE) in a cross-section of routine cardiac surgery patients. DESIGN: Retrospective, observational study. SETTING: Tertiary, academic referral hospital. PARTICIPANTS: Patients undergoing elective cardiac surgery with intraoperative transesophageal echocardiography (TEE) imaging. INTERVENTIONS: TEE imaging was reviewed and evaluated for the following three different measurements of transthoracic echocardiography-TAPSE surrogates: 2D-TAPSE, 2D-TAPSE-apex, and STE-TAPSE. Statistical analyses, including 2-sample t tests, linear regression, and agreement using the Bland-Altman methods, were performed. MEASUREMENTS AND MAIN RESULTS: Modest correlation was demonstrated between STE-TAPSE and 2D-TAPSE (R2 = 0.37; p < 0.001) and between STE-TAPSE and 2D-TAPSE-apex (R2 = 0.34; p < 0.001). There was good correlation between 2D-TAPSE and 2D-TAPSE-apex (R2 = 0.77, p < 0.001). The Bland-Altman analysis between these methods showed minimal bias: STE-TAPSE and 2D-TAPSE 0.84 mm, STE-TAPSE and 2D-TAPSE-apex 0.14 mm, and 2D-TAPSE and 2D-TAPSE-apex 0.98 mm. However, the agreement was poor, with 95% limits of agreement of -10.67 to 8.99 mm, -10.67 to 10.96 mm, and -4.91 to 6.88 mm, respectively. CONCLUSIONS: Correlation and minimal bias were found between the several proposed TEE surrogates of transthoracic echocardiography-TAPSE; however, there was poor agreement. Therefore, these surrogates are not interchangeable, and each method needs to be separately validated for clinical use to relevant perioperative outcomes.


Assuntos
Pressão Sanguínea/fisiologia , Procedimentos Cirúrgicos Cardíacos/normas , Ecocardiografia Transesofagiana/normas , Monitorização Intraoperatória/normas , Valva Tricúspide/efeitos dos fármacos , Valva Tricúspide/fisiologia , Idoso , Procedimentos Cirúrgicos Cardíacos/métodos , Estudos de Coortes , Ecocardiografia/métodos , Ecocardiografia/normas , Ecocardiografia Transesofagiana/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória/métodos , Estudos Retrospectivos
7.
Acta Biomater ; 85: 241-252, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30579963

RESUMO

BACKGROUND: Healthy function of tricuspid valve (TV) structures is essential to avoid tricuspid regurgitation (TR) and may significantly improve disease prognosis. Mitral valve (MV) structures have been extensively studied, but little is known about the TV and right-sided heart diseases. Therefore, clinical decisions and finite element (FE) simulations often rely heavily on MV data for TV applications, despite fundamentally different mechanical and physiological environments. METHOD/RESULTS: To bridge this gap, we performed a rigorous mechanical, morphological, and microstructural characterization of the MV and TV leaflets and chordae in a porcine model. Planar biaxial testing, uniaxial testing, second harmonic generation imaging and Verhoeff Van Gieson staining were performed. Morphological parameters, tissue moduli, extensibility, and anisotropy were quantified and compared. No major differences in leaflet mechanics or structure were found between TV and MV; chordal mechanics, morphology, and structure were found to compensate for anatomical and physiological loading differences between the valves. No differences in chordal mechanics were observed by insertion point within a leaflet; the septal tricuspid leaflet (STL) and posterior mitral leaflet (PML) did not have distinguishable strut chords, and the STL had the shortest chords. Within a valve, chords from septally-located leaflets were more extensible. MV chords were stiffer. CONCLUSIONS: This study presents the first rigorous comparative mechanical and structural dataset of MV and TV structures. Valve type and anatomical location may be stronger predictors of chordal mechanics. Chords from septally-located leaflets differ from each other and from their intravalvular counterparts; they merit special consideration in surgical and computational applications. STATEMENT OF SIGNIFICANCE: A better understanding of the tricuspid valve (TV) and its associated structures is important for making advancements towards the repair of tricuspid regurgitation. Mitral valve structures have been extensively studied, but little is known about the TV and right-sided heart diseases. Clinical decisions and computational simulations often rely heavily on MV data for TV applications, despite fundamentally different environments. We therefore performed a rigorous mechanical, morphological, and microstructural characterization of atrioventricular leaflets and chordae tendineae in a porcine model. Finding that valve type and anatomical location may be strong predictors of chordal mechanics, chords from septally-located leaflets differ from each other and from their intravalvular counterparts; they merit special consideration in surgical and computational applications.


Assuntos
Cordas Tendinosas/anatomia & histologia , Cordas Tendinosas/fisiologia , Valva Mitral/anatomia & histologia , Valva Mitral/fisiologia , Valva Tricúspide/anatomia & histologia , Valva Tricúspide/fisiologia , Animais , Fenômenos Biomecânicos , Modelos Biológicos , Suínos
8.
JACC Cardiovasc Imaging ; 12(3): 401-412, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-29153573

RESUMO

OBJECTIVES: The authors used transthoracic 3-dimensional transthoracic echocardiography (3DE) to characterize tricuspid annulus (TA) geometry and dynamics in healthy volunteers. BACKGROUND: Accurate sizing of the TA is essential for planning tricuspid annuloplasty and for implantation of new percutaneous tricuspid devices. METHODS: 3DE of the TA from 209 healthy volunteers was analyzed using custom software to measure TA area, perimeter, circularity, and dimensions at end diastole (equals tricuspid valve closure), mid-systole, end systole, and late diastole. TA intercommissural distances were measured at mid-systole. For comparison, TA diameters were measured at the same time points on multiplanar reconstruction of the 3DE datasets and on 2-dimensional transthoracic echocardiography (2DE) apical 4-chamber and right ventricular focused views. In 13 subjects with both 3DE and computed tomography, TA parameters were compared. RESULTS: 3DE TA area, perimeter, and dimensions were largest in late diastole and smallest at mid-systole/end systole. Normal tricuspid valve parameters in end diastole were 8.6 ± 2.0 cm2 for area; 10.5 ± 1.2 cm for perimeter; 36 ± 4 mm and 30 ± 4 mm for longest and shortest dimensions, respectively; and 0.83 ± 0.10 for circularity. There were no age-related changes in TA parameters. Women had larger indexed TA perimeter and longer long-axis dimensions compared with men. The longest 3DE TA dimension was significantly longer than diameters measured from both 2DE and 3D multiplanar reconstruction. 3DE TA area, perimeter, and dimensions correlated with both right atrial and right ventricular volumes, suggesting that both chambers may be determinants of TA size. TA fractional area change was 35 ± 10%. Fractional changes in both perimeter and dimensions were ≥20%. When compared with computed tomography, 3DE systematically underestimated TA parameters. CONCLUSIONS: Gender and body size should be taken into account to identify the reference values of TA dimensions. 2DE underestimates TA dimensions.


Assuntos
Ecocardiografia Tridimensional , Hemodinâmica , Valva Tricúspide/diagnóstico por imagem , Valva Tricúspide/fisiologia , Adulto , Tamanho Corporal , Chicago , Diástole , Feminino , Voluntários Saudáveis , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Fatores Sexuais , Sístole , Tomografia Computadorizada por Raios X
9.
IEEE Trans Biomed Circuits Syst ; 12(6): 1392-1400, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30113900

RESUMO

In this paper, we investigate the feasibility of harvesting energy from cardiac valvular perturbations to self-power a wireless sonomicrometry sensor. Compared to the previous studies involving piezoelectric patches or encasings attached to the cardiac or aortic surface, the proposed study explores the use of piezoelectric sutures that can be implanted in proximity to the valvular regions, where non-linear valvular perturbations could be exploited for self-powering. Using an ovine animal model, the magnitude of valvular perturbations are first measured using an array of sonomicrometry crystals implanted around the tricuspid valve. These measurements were then used to estimate the levels of electrical energy that could be harvested using a simplified piezoelectric suture model. These results were revalidated across seven different animals, before and after valvular regurgitation was induced. Our study shows that power harvested from different annular planes of the tricuspid valve (before and after regurgitation) could range from nano-watts to milli-watts, with the maximum power harvested from the leaflet plane. We believe that these results could be useful for determining optimal surgical placement of wireless and self-powered sonomicrometry sensor, which in turn could be used for investigating the pathophysiology of ischemic regurgitation.


Assuntos
Engenharia Biomédica/instrumentação , Valvas Cardíacas/fisiologia , Telemetria/instrumentação , Valva Tricúspide/fisiologia , Ultrassom/instrumentação , Animais , Fontes de Energia Elétrica , Desenho de Equipamento , Estudos de Viabilidade , Ovinos
10.
Zhonghua Xin Xue Guan Bing Za Zhi ; 46(8): 611-616, 2018 Aug 24.
Artigo em Chinês | MEDLINE | ID: mdl-30139011

RESUMO

Object: To explore the electrocardiographic characteristics of ventricular arrhythmias (VAs) originating from tricuspid annulus region. Methods: Present study included 169 consecutive patients undergoing catheter ablation of VAs from tricuspid annulus origin in our department from August 2007 to September 2016. Based on the origin sites, the patients were divided into two subgroups, the free wall group (81 cases) and septal wall group (88 cases). Based on the location, patients in the free wall group were classified into anterolateral (22 cases), lateral (26 cases) and posterolateral (33 cases) subgroups. Patients in the septal group were classified into anteroseptal (10 cases), midseptal (71 cases) and posteroseptal (7 cases) subgroups. We analyzed the electrocardiographic features of these patients and in 87 patients with PVCs/VT originating from right ventricular outflow tract. Results: (1) A positive R wave inⅠ, aVL, V(5)-V(6) leads were found among most of patients, only few cases originating from tricuspid annulus anteroseptum group and tricuspid annulus anterolateral group demonstrated qr or qs pattern in aVL lead. 97.53% (79/81) patients demonstrated rS pattern in V(1)-V(3) leads with VAs originating from tricuspid annulus free wall, and 9/10 patients demonstrated rS pattern in V(1) lead with VAs originating from anteroseptum, and 97.44% (76/78) patients demonstrated QS pattern in V(1) lead with VAs originating from midseptum and posteroseptum. Precordial lead transition zone was on or behind V(3) for tricuspid annulus free wall group (96.3%, 78/81), but in front of V(3) for tricuspid annulus septum wall group (47.73%, 42/88) (P<0.01). The S wave's amplitude smaller than-1.81 mV in lead V(2) can be used as a cutoff value to identify if PVC/VT is originating from free wall or septum of TA. R wave in inferior wall leads was found among 98.85% (86/87) patients with PVCs/VT originating from right ventricular outflow tract. Conclusion: A positive R wave in Ⅰ, aVL, V(5)-V(6) leads was found among most of patients with idiopathic ventricular arrhythmias originating from the tricuspid annulus regions, but VAs originating from different portions of tricuspid annulus area have distinct electrocardiographic characteristics.


Assuntos
Ablação por Cateter , Sistema de Condução Cardíaco , Taquicardia Ventricular , Eletrocardiografia , Ventrículos do Coração , Humanos , Taquicardia Ventricular/fisiopatologia , Taquicardia Ventricular/terapia , Valva Tricúspide/fisiologia , Complexos Ventriculares Prematuros
11.
Ann Thorac Surg ; 106(6): 1804-1811, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29958829

RESUMO

BACKGROUND: Tricuspid valve repair using suture annuloplasty is thought to be more physiologic, but the effect of annular reduction on annular geometry and motion is unknown. We set out to investigate the effect of DeVega suture annuloplasty (DV) on tricuspid annular geometry and dynamics during acute right heart failure (RHF). METHODS: Ten adult sheep underwent implantation of sonomicrometry crystals around the tricuspid annulus and on the right ventricle; pressure transducers were placed in right ventricle, left ventricle, and right atrium. RHF was induced by a combination of 500 mL volume infusion, posterior descending artery occlusion, and pulmonary artery constriction. Hemodynamic, echocardiographic, and sonomicrometry data were acquired at baseline, with RHF, and after two progressive (8 to 10 mm) DV suture cinches (DV-1, DV-2) during RHF. Annular size, geometry, and dynamics were determined from crystal coordinates. RESULTS: Combination of volume infusion, ischemia, and pulmonary hypertension resulted in acute RHF and significant functional tricuspid regurgitation grade (0.5 ± 0.5 versus 2.7 ± 0.8, p < 0.001). Annular area increased with RHF from 700 ± 98 mm2 to 801 ± 128 mm2 (p < 0.001). DV-1 and DV-2 reduced annular area to 342 ± 88 mm2 and 180 ± 57 mm2 while reducing regurgitation grade to 1.2 ± 0.4 and 0.4 ± 0.5, respectively (all p < 0.001 versus RHF). Tricuspid annular area contraction was 12% ± 7%, 10% ± 6%, and 12% ± 6% for RHF, DV-1, and DV-2, respectively (p = 0.25) and annular height was 4.9 ± 2.0 mm, 5.6 ± 1.4 mm, and 5.5 ± 1.7 mm (p = 0.43). Mean transvalvular gradient was 1.3 ± 0.7 mm Hg and 2.0 ± 1.0 mm Hg with DV-1 and DV-2, respectively. CONCLUSIONS: During acute ovine RHF, DeVega annuloplasty successfully treated tricuspid regurgitation and preserved normal tricuspid annular dynamics and geometry. These data may lead to more physiologic tricuspid reparative techniques.


Assuntos
Anuloplastia da Valva Cardíaca/métodos , Técnicas de Sutura , Insuficiência da Valva Tricúspide/cirurgia , Valva Tricúspide/anatomia & histologia , Valva Tricúspide/fisiologia , Doença Aguda , Animais , Fenômenos Biomecânicos , Insuficiência Cardíaca/complicações , Humanos , Masculino , Ovinos , Valva Tricúspide/cirurgia , Insuficiência da Valva Tricúspide/etiologia
12.
Int J Numer Method Biomed Eng ; 34(10): e3117, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29905015

RESUMO

The aortic valve is normally composed of 3 cusps. In one common lesion, 2 cusps are fused together. The conjoined area of the fused cusps is termed raphe. Occurring in 1% to 2% of the population, the bicuspid aortic valve (BAV) is the most common congenital cardiac malformation. The majority of BAV patients eventually require surgery. There is a lack in the literature regarding modeling of the raphe (geometry and material properties), its role and its influence on BAV function. The present study aims to propose improvements on these aspects. Three patient-specific finite element models of BAVs were created based on 3D trans-esophageal echocardiography measurements, and assuming age-dependent material properties. The raphe was initially given the same material properties as its underlying cusps. Two levels of validation were performed; one based on the anatomical validation of the pressurized geometry in diastole (involving 7 anatomical measures), as simulated starting from the unpressurized geometry, and the other based on a functional assessment using clinical measurements in both systole and diastole (involving 16 functional measures). The pathology was successfully reproduced in the FE models of all 3 patients. To further investigate the role of the raphe, 2 additional scenarios were considered; (1) the raphe was considered as almost rigid, (2) the raphe was totally removed. The results confirmed the interpretation of the raphe as added stiffness in the fused cusp's rotation with respect to the aortic wall, as well as added support for stress distribution from the fused cusps to the aortic wall.


Assuntos
Valva Aórtica/anormalidades , Análise de Elementos Finitos , Doenças das Valvas Cardíacas/fisiopatologia , Algoritmos , Aorta/anatomia & histologia , Aorta/fisiopatologia , Valva Aórtica/fisiopatologia , Fenômenos Biomecânicos , Diástole/fisiologia , Ecocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Cardiovasculares , Índice de Gravidade de Doença , Sístole/fisiologia , Valva Tricúspide/fisiologia
13.
J Thorac Cardiovasc Surg ; 156(4): 1503-1511, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29804662

RESUMO

OBJECTIVES: Clinical and experimental tricuspid valve physiology data are derived predominantly from anesthetized subjects, but normal tricuspid valve geometry and dynamics may be altered by general anesthesia and mechanical ventilation. We set out to investigate 3-dimensional geometry and dynamics of the tricuspid valve complex in awake and anesthetized sheep. METHODS: While on cardiopulmonary bypass and with the heart beating, 6 adult sheep (50 ± 8 kg) underwent implantation of 6 sonomicrometry crystals around the tricuspid annulus. One crystal was implanted on the anterior, posterior, and septal papillary muscle tips, 4 on the right ventricular free wall and 1 on its apex. Pressure transducers were placed in both ventricles. Sonomicrometry and pressure transducer cables were externalized to subcutaneous buttons. After 7 days of recovery, hemodynamic and sonomicrometry data were recorded with animals awake and anesthetized. RESULTS: Hemodynamic parameters did not differ between groups. Tricuspid annular area contraction decreased with anesthesia (16.4% ± 4.2% vs 11.2% ± 3.2%, P = .047) as did tricuspid annular perimeter contraction (8.1% ± 2.2% vs 5.4% ± 1.7%, P = .050), predominantly due to reduced contraction of the septal annulus (10.5% ± 2.9% vs 7.5% ± 3.5%, P = .019). Tricuspid annular height did not differ between groups. Minimal distance from anterior, posterior, and septal papillary muscle tips to the annular plane did not change with anesthesia. Regional right ventricle free wall contraction was depressed under anesthesia in anterior (16.3% ± 3.1% vs 12.3% ± 2.2%, P = .027) and lateral (14.9% ± 1.3% vs 11.5% ± 2.8%, P = .016) segments, whereas the posterior remained unchanged. CONCLUSIONS: General anesthesia did not alter tricuspid annular or subvalvular 3-dimensional geometry but reduced right ventricular contraction and tricuspid annular dynamics.


Assuntos
Valva Tricúspide/fisiologia , Anestesia Geral , Animais , Ponte Cardiopulmonar , Hemodinâmica , Imagem Tridimensional , Masculino , Respiração Artificial , Ovinos , Valva Tricúspide/anatomia & histologia
14.
Cardiovasc Eng Technol ; 9(2): 217-225, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29484539

RESUMO

The Tricuspid valve (TV) annulus is a transition structure from the leaflets to the myocardium, with 3 different annulus segments corresponding to the TV leaflets, which includes both basal leaflets and bordering myocardium. The objective of this study was to understand TV annulus mechanical properties and correlate it to the biological composition. The uniaxial testing of the annulus segments from ten porcine TVs was performed to measure Young's modulus (E) and extensibility (εT). Western blotting and histology were executed. The septal annulus E value (208.7 ± 67.2 kPa) was statistically greater (p < 0.01) than that of the anterior (92.0 ± 66.8 kPa) and the posterior annulus segment (136.8 ± 56.9 kPa) (p < 0.05), respectively. εT among the 3 segments were equivalent (p values < 0.05). Western blotting and histology indicated that collagen was greatest along the septal annulus segment, which is correlated to E values. Collagen fibers from the leaflets inserted into the myocardium and faded out. Collagen content explains greater E and suture strength in the surgical annulus repair and larger resistance to annulus dilation in the septal annulus as compared with other segments. This study elucidates new knowledge of mechanical properties of the basal leaflet-annulus region of the TV annulus, which can be useful for future TV repair techniques.


Assuntos
Mecanotransdução Celular , Valva Tricúspide/fisiologia , Animais , Fenômenos Biomecânicos , Anuloplastia da Valva Cardíaca , Módulo de Elasticidade , Colágenos Fibrilares/metabolismo , Estresse Mecânico , Sus scrofa , Técnicas de Sutura , Resistência à Tração , Valva Tricúspide/anatomia & histologia , Valva Tricúspide/metabolismo , Valva Tricúspide/cirurgia
15.
Anesth Analg ; 126(1): 62-67, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29116970

RESUMO

BACKGROUND: The perioperative assessment of right ventricular (RV) function remains a challenge. Tricuspid annular plane systolic excursion (TAPSE) using M-mode is a widely used measure of RV function. However, accurate alignment of the ultrasound beam with the direction of annular movement can be difficult with transesophageal echocardiography (TEE) to measure TAPSE, precluding effective use of M-mode to measure annular excursion. Tracking of specular reflectors in the myocardium may provide an angle-independent method to assess annular motion with TEE. We hypothesized that TEE speckle tracking of the lateral tricuspid annular motion represents a comparable measurement to the well-validated M-mode TAPSE on transthoracic echocardiogram (TTE), and may be considered as a reasonable alternative to TAPSE. METHODS: This is a prospective, observational cohort study. We included all patients, who were in sinus rhythm, with a preoperative TTE within 3 months of scheduled cardiac surgery that required intraoperative TEE. Tissue motion annular displacements (TMAD) of the lateral (L), septal (S), and midpoint (M) tricuspid annulus were measured (QLAB Cardiac Motion Quantification; Philips Medical, Andover, MA) after induction of general anesthesia. This was compared to the preoperative M-mode TAPSE on TTE. RESULTS: Seventy-two consecutive patients who met eligibility requirements were enrolled from September to November 2016. Twelve were excluded due to poor image quality, allowing TMAD to be analyzed in 60 patients. TMAD was analyzed offline and TMAD analysis was able to track tricuspid annular motion in all patients. The mean TMAD (L), TMAD (S), and TMAD (M) were 17.4 ± 5.2, 10.2 ± 4.8, and 14.2 ± 4.8 mm, respectively. TMAD (L) showed close correlation with M-mode TAPSE on TTE (r = 0.87, 95% confidence interval, 0.79-0.92; P < .01). All patients with a preoperative TAPSE <17 mm had a TMAD (L) <17 mm, while 71% of those with a TAPSE ≥ 17 mm had a TMAD (L) ≥ 17 mm. There was strong positive correlation between TMAD (L) and intraoperative RV fractional area change (r = 0.86, 95% confidence interval, 0.77-0.91; P < .01). Reproducibility analysis of TMAD within and across observers showed excellent correlation. CONCLUSIONS: TMAD is a quick and angle-independent method to quantitatively assess RV longitudinal function by TEE. It correlates strongly with M-mode TAPSE on TTE. Because TMAD and TAPSE were not simultaneously measured in this study, their correlation is subject to differences in loading conditions, general anesthesia, and changes in the disease process. TMAD may be easily applied in routine clinical settings and its role in the perioperative environment deserves to be further explored.


Assuntos
Anestesia Geral , Ecocardiografia Transesofagiana/estatística & dados numéricos , Monitorização Intraoperatória , Valva Tricúspide/diagnóstico por imagem , Valva Tricúspide/fisiologia , Função Ventricular Direita/fisiologia , Idoso , Anestesia Geral/métodos , Estudos de Coortes , Ecocardiografia Transesofagiana/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória/métodos , Estudos Prospectivos
17.
J Am Coll Cardiol ; 69(18): 2331-2341, 2017 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-28473139

RESUMO

The potential for cardiac implantable electronic device leads to interfere with tricuspid valve (TV) function has gained increasing recognition as having hemodynamic and clinical consequences associated with incremental morbidity and death. The diagnosis and treatment of lead-related (as distinct from functional) tricuspid regurgitation pose unique challenges. Because of pitfalls in routine diagnostic imaging, a high level of clinical suspicion must be maintained to avoid overlooking the possibility that worsening heart failure is a consequence of mechanical interference with TV leaflet mobility or coaptation and is amenable to lead extraction or valve repair or replacement. The future of cardiac implantable electronic devices includes pacing and perhaps defibrillation without a lead traversing the TV.


Assuntos
Desfibriladores Implantáveis/efeitos adversos , Complicações Pós-Operatórias/etiologia , Insuficiência da Valva Tricúspide/etiologia , Remoção de Dispositivo , Humanos , Valva Tricúspide/anatomia & histologia , Valva Tricúspide/fisiologia , Insuficiência da Valva Tricúspide/cirurgia
18.
Echocardiography ; 34(6): 810-816, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28386967

RESUMO

BACKGROUND: Even though the tricuspid annulus (TA) is anatomically and functionally related to right atrioventricular dependence and tricuspid annular plane systolic excursion (TAPSE) is a well-known measure of right ventricular (RV) systolic function, there is paucity of data regarding the potential impact that right atrial (RA) size and function have on TAPSE. Hence, we sought to determine whether RA volumetric and longitudinal measures affect TAPSE in patients with chronic pulmonary hypertension (cPH). METHODS: In this retrospective study, echocardiographic data from 110 patients were reviewed and the studied population was divided into Group I consisting of 50 patients (50±11 years) without PH and Group II that included 60 patients (55±14 years) with cPH. RESULTS: Even though RA areas, RA fractional area change, and maximal long-axis length measurements were abnormal in cPH patients, TA tissue Doppler imaging systolic velocity and RV fractional area change were the only useful variables in identifying patients with abnormal TAPSE (P<.0001 and P=.018, respectively). Additionally, TAPSE was independent of all RA measures, left ventricular ejection fraction, and age (P>.05). CONCLUSIONS: Based on these results, TAPSE does not appear to be influenced by either RA size or function. Additional studies using strain echocardiography to interrogate RA mechanics might now be very useful to advance our understanding of TA motion in cPH patients given recent data showing that RA function accounts for a significantly greater proportion of total right heart function in patients with cPH than in normal subjects.


Assuntos
Hipertensão Pulmonar/fisiopatologia , Valva Tricúspide/fisiologia , Disfunção Ventricular Direita/fisiopatologia , Doença Crônica , Ecocardiografia Doppler , Feminino , Átrios do Coração/fisiopatologia , Humanos , Hipertensão Pulmonar/complicações , Hipertensão Pulmonar/patologia , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Estudos Retrospectivos , Sístole , Disfunção Ventricular Direita/complicações
19.
Int J Cardiovasc Imaging ; 33(5): 721-729, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28110433

RESUMO

Cardiac valve plane displacement (CVPD) reflects longitudinal LV function. The purpose of the present study was to determine regional heterogeneity of CVPD in healthy adults to provide normal values by cardiac magnetic resonance (CMR). We measured the anterior aortic plane systolic excursion (AAPSE); the anterior, anterolateral, inferolateral, inferior, and inferoseptal mitral annular plane systolic excursion (MAPSE); and the lateral tricuspid annulus plane systolic excursion (TAPSE). Systolic excursion was measured as the distance from peak end-diastolic to peak end-sysstolic annular position (peak-to-peak) in cine images acquired in 2-, 3- and 4-chamber views. Echocardiographic measurements of CVPD were performed in M-Mode as previously described. We retrospectively analyzed 209 healthy Caucasians (57% men), who participated in the Heidelberg normal cohort between March 2009 and September 2014. The analysis was possible in all participants. Mean values were: AAPSE = 14 ± 3 mm (8-20); MAPSEanterior = 14 ± 3 mm (8-20); MAPSEanterolateral = 16 ± 3 mm (10-22); MAPSEinferolateral = 16 ± 3 mm (10-22); MAPSEinferior = 17 ± 3 mm (11-23); MAPSEinferoseptal = 13 ± 3 mm (7-19) and TAPSE = 26 ± 4 mm (18-34) respectively. MAPSE was significantly elevated in lateral compared to septal regions (p = 0.0001). Sex-differences for CVPD were not found. Age-dependency of CVPD revealed distinct regional differences. AAPSE decreased the most with age (B=-0.48; p = 0.0001), whereas MAPSEinferior was the least age-dependent site (B=-0.17; p = 0.01). AAPSE revealed favorable intra-/interobserver reproducibility and interstudy agreement. Intermethod-comparison of CMR and M-Mode echocardiography showed good agreement between both measurements of CVPD. Age-stratified normal values of regional CVPD are provided. AAPSE revealed the most pronounced age-related decrease and provided favorable reproducibility compared to other regions of cardiac valve plane.


Assuntos
Valva Aórtica/diagnóstico por imagem , Imagem Cinética por Ressonância Magnética , Valva Mitral/diagnóstico por imagem , Valva Tricúspide/diagnóstico por imagem , Função Ventricular Esquerda , Adulto , Distribuição por Idade , Valva Aórtica/fisiologia , Ecocardiografia , Grupo com Ancestrais do Continente Europeu , Feminino , Alemanha , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/fisiologia , Variações Dependentes do Observador , Valor Preditivo dos Testes , Valores de Referência , Reprodutibilidade dos Testes , Estudos Retrospectivos , Valva Tricúspide/fisiologia
20.
J Biomech ; 50: 63-70, 2017 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-27855987

RESUMO

Bicuspid aortic valves (BAVs) generate flow abnormalities that may promote aortopathy. While positive helix fraction (PHF) index, flow angle (θ), flow displacement (d) and wall shear stress (WSS) exhibit abnormalities in dilated BAV aortas, it is unclear whether those anomalies stem from the abnormal valve anatomy or the dilated aorta. Therefore, the objective of this study was to quantify the early impact of different BAV morphotypes on aorta hemodynamics prior to dilation. Fluid-structure interaction models were designed to quantify standard peak-systolic flow metrics and temporal WSS characteristics in a realistic non-dilated aorta connected to functional tricuspid aortic valve (TAV) and type-I BAVs. While BAVs generated increased helicity (PHF>0.68) in the middle ascending aorta (AA), larger systolic flow skewness (θ>11.2°) and displacement (d>6.8mm) relative to the TAV (PHF=0.51; θ<5.5°; d<3.3mm), no distinct pattern was observed between morphotypes. In contrast, WSS magnitude and directionality abnormalities were BAV morphotype- and site-dependent. Type-I BAVs subjected the AA convexity to peak-systolic WSS overloads (up to 1014% difference vs. TAV). While all BAVs increased WSS unidirectionality on the proximal AA relative to the TAV, the most significant abnormality was achieved by the BAV with left-right-coronary cusp fusion on the wall convexity (up to 0.26 decrease in oscillatory shear index vs. TAV). The results indicate the existence of strong hemodynamic abnormalities in non-dilated type-I BAV AAs, their colocalization with sites vulnerable to dilation and the superior specificity of WSS metrics over global hemodynamic metrics to the valve anatomy.


Assuntos
Aorta/fisiologia , Valva Aórtica/anormalidades , Modelos Cardiovasculares , Doenças da Aorta/fisiopatologia , Valva Aórtica/anatomia & histologia , Valva Aórtica/fisiologia , Doenças das Valvas Cardíacas , Hemodinâmica , Humanos , Estresse Mecânico , Valva Tricúspide/fisiologia
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