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1.
Angiology ; 71(2): 139-149, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31694385

RESUMO

The relative superiority of angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) on long-term clinical outcomes in patients with non-ST-segment elevation myocardial infarction (NSTEMI) with preserved left ventricular systolic function in the era of new generation drug-eluting stents is not well established. A total of 6436 patients with NSTEMI (ACEIs group: n = 3965 vs ARBs group: n = 2471) were enrolled. The major clinical end point was the occurrences of major adverse cardiac events (MACEs), defined as all-cause death, recurrent myocardial infarction (re-MI), and any repeat revascularization. After propensity score matching analysis, the cumulative incidences of MACEs (hazard ratio, 1.334; 95% confidence interval, 1.045-1.703; P = .021), any repeat revascularization, and target vessel revascularization (TVR) in the ARB group were significantly higher than that in the ACEI group. However, the cumulative incidences of all-cause death, cardiac death, re-MI, target lesion revascularization, and non-TVR were similar between the 2 groups. Hence, although the mortality and re-MI reduction benefits were similar between the 2 groups, the ACEIs group showed more prominent ability to decrease the occurrences of MACEs, any repeat revascularization, and TVR compared to the ARBs group in these patients during a 2-year follow-up period.


Assuntos
Antagonistas de Receptores de Angiotensina/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Stents Farmacológicos , Infarto do Miocárdio sem Supradesnível do Segmento ST/cirurgia , Intervenção Coronária Percutânea , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sístole/fisiologia , Função Ventricular Esquerda/fisiologia
2.
Comput Methods Biomech Biomed Engin ; 23(1): 33-42, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31805773

RESUMO

This study numerically investigated the hemodynamics of a patient-specific coronary artery fistula (CAF) before and after the fistula closure. The results indicated that the dilated fistula result in inadequate perfusion to other healthy aortas. Disturbed blood flow, aberrant WSSs, local negative pressure gradients and sharp pressure changes are shown in both untreated and occluded fistula. Furthermore, extreme high WSS appeared at the fistula bending after the terminal closure. It was concluded that the fistula closure may effectively improve the phenomenon of stealing blood but worsen the unfavorable hemodyanmics predisposing the thrombosis formation due to its geometrical torturosity.


Assuntos
Vasos Coronários/fisiopatologia , Fístula/fisiopatologia , Hidrodinâmica , Adulto , Doença da Artéria Coronariana/fisiopatologia , Diástole/fisiologia , Hemorreologia , Humanos , Imagem Tridimensional , Masculino , Modelos Cardiovasculares , Pressão , Estresse Mecânico , Sístole/fisiologia
4.
Braz J Cardiovasc Surg ; 34(4): 451-457, 2019 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-31454199

RESUMO

OBJECTIVE: To evaluate the aortic wall elasticity using the maximal rate of systolic distension (MRSD) and maximal rate of diastolic recoil (MRDR) and their correlation with the aortic size index (ASI). METHODS: Forty-eight patients with thoracic aortic aneurysm were enrolled in this study. A standard magnetic resonance imaging (MRI) protocol was used to calculate MRSD and MRDR. Both MRSD and MRDR were expressed as percentile of maximal area/10-3 sec. ASI (maximal aortic diameter/body surface area) was calculated. A correlation between MRSD, MRDR, ASI, and the patient's age was performed using regression plot. RESULTS: A significant correlation between MRSD (t=-4,36; r2=0.29; P≤0.0001), MRDR (t=3.92; r2=0.25; P=0.0003), and ASI (25±4.33 mm/m2; range 15,48-35,14 mm/m2) is observed. As ASI increases, aortic MRSD and MRDR decrease. Such inverse correlation between MRSD, MRDR, and ASI indicates increased stiffness of the ascending aorta. A significant correlation between the patient's age and the decrease in MRSD and MRDR is observed. CONCLUSION: MRSD and MRDR are significantly correlated with ASI and the patient's age. They seem to describe properly the increasing stiffness of aortas. These two new indexes provide a promising, accessible, and reproducible approach to evaluate the biomechanical property of the aorta.


Assuntos
Aneurisma Dissecante/diagnóstico por imagem , Aorta/fisiopatologia , Aneurisma da Aorta Torácica/diagnóstico por imagem , Imagem por Ressonância Magnética , Adulto , Idoso , Diástole/fisiologia , Dilatação Patológica , Elasticidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sístole/fisiologia
5.
Hypertension ; 74(4): 880-887, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31422691

RESUMO

Recent data suggest that visit-to-visit variability of blood pressure (BP) is associated with cardiovascular events. We evaluated the role of BP variability as a determinant of end-stage renal disease (ESRD). Using nationally representative data from the Korean National Health Insurance System, 8 199 089 subjects had been enrolled during 2009 to 2010 who were free of ESRD and underwent ≥3 health examinations during 2005 to 2010 were followed to the end of 2017. BP variability was measured using the coefficient of variation, SD, and variability independent of the mean. The primary outcome was the development of ESRD, defined as a combination of the relevant disease code and the initiation of renal replacement therapy. The χ2 test, t test, and log-rank test were used in the statistical analysis. There were 16 567 cases of ESRD during a median follow-up of 7.89±0.88 years. The highest quartile of systolic or diastolic BP showed a higher incident rate of ESRD compared with the other 3 quartiles. It was augmented in patients with the highest quartile of both systolic and diastolic BP variabilities. Among patients with the highest quartile of systolic and diastolic BP variabilities, the uncontrolled hypertension group (>140/90 mm Hg) taking antihypertensive medication showed the highest incidence rate of ESRD. These results were consistent when modeling variability of BP using coefficient of variation, SD, and variability independent of the mean and in various sensitivity analyses. Systolic and diastolic BP variabilities were independently associated with an increased incidence of ESRD, and it was augmented when both variabilities were present together.


Assuntos
Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/fisiologia , Hipertensão/fisiopatologia , Falência Renal Crônica/epidemiologia , Adulto , Determinação da Pressão Arterial , Diástole/fisiologia , Feminino , Taxa de Filtração Glomerular/fisiologia , Inquéritos Epidemiológicos , Humanos , Hipertensão/tratamento farmacológico , Incidência , Falência Renal Crônica/fisiopatologia , Masculino , Pessoa de Meia-Idade , República da Coreia/epidemiologia , Risco , Sístole/fisiologia
6.
PLoS One ; 14(7): e0218785, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31291276

RESUMO

Recently, some authors have suggested that age-related impairments in social-cognitive abilities-emotion recognition (ER) and theory of mind (ToM)-may be explained in terms of reduced motivation and effort mobilization in older adults. We examined performance on ER and ToM tasks, as well as corresponding control tasks, experimentally manipulating self-involvement. Sixty-one older adults and 57 young adults were randomly assigned to either a High or Low self-involvement condition. In the first condition, self-involvement was raised by telling participants were told that good task performance was associated with a number of positive, personally relevant social outcomes. Motivation was measured with both subjective (self-report questionnaire) and objective (systolic blood pressure reactivity-SBP-R) indices. Results showed that the self-involvement manipulation did not increase self-reported motivation, SBP-R, or task performance. Further correlation analyses focusing on individual differences in motivation did not reveal any association with performance, in either young or older adults. Notably, we found age-related decline in both ER and ToM, despite older adults having higher motivation than young adults. Overall, the present results were not consistent with previous claims that motivation affects older adults' social-cognitive performance, opening the route to potential alternative explanations.


Assuntos
Sistema Cardiovascular , Cognição/fisiologia , Função Executiva/fisiologia , Motivação/fisiologia , Habilidades Sociais , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Autorrelato , Sístole/fisiologia , Análise e Desempenho de Tarefas , Teoria da Mente
7.
Australas Phys Eng Sci Med ; 42(3): 733-743, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31313129

RESUMO

The problem addressed in this work is the detection of a heart murmur and the classification of the associated cardiovascular disorder based on the heart sound signal. For this purpose, a dataset of Phonocardiogram (PCG) signals is acquired using baseline conditions. The dataset is acquired from 283 volunteers using Littman 3200 electronic stethoscope for a normal and four different types of heart murmurs. The samples are labelled and validated through echocardiography test of each participating volunteer. For feature extraction, normalized average Shannon energy with time-domain characteristics of heart sound signal is exploited to segment the PCG signal into its components. To improve the quality of the features, in contrast to the previous methods, all systole and diastole intervals are utilized to extract 50 Mel-Frequency Cepstrum Coefficients (MFCC) based features. Then, the iterative backward elimination method is used to identify and remove the redundant features to reduce the complexity in order to conceive a computationally tractable system. An MFCC feature vector of dimension 26 is selected for training seven different types of Support Vector Machine (SVM) and K-Nearest Neighbors (KNN) based classifiers for detection and classification of cardiovascular disorders. Fivefold cross-validation and 20% data holdout validation schemes are used for testing the classifiers. Classification accuracy of 92.6% is achieved using selected features and medium Gaussian SVM classifier. The learning curves show a good bias-variance trade-off indicating a well-fitted and generalized model for making future predictions.


Assuntos
Algoritmos , Sopros Cardíacos/diagnóstico , Adulto , Diástole/fisiologia , Feminino , Sopros Cardíacos/fisiopatologia , Ruídos Cardíacos , Humanos , Masculino , Pessoa de Meia-Idade , Fonocardiografia , Processamento de Sinais Assistido por Computador , Máquina de Vetores de Suporte , Sístole/fisiologia
8.
Eur J Pharmacol ; 859: 172519, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31271743

RESUMO

Juvenile Paget disease (JPD1), an autosomal-recessive disorder, is characterized by extremely rapid bone turnover due to osteoprotegerin deficiency. Its extra-skeletal manifestations, such as hypertension and heart failure, suggest a pathogenesis with shared skeletal and cardiovascular system components. In spite of this, the effects of anti-hypertensive drugs on bone morphometry remain unknown. We administered an angiotensin II type 1 receptor blocker, olmesartan (5 mg/kg/day) to 8-week-old male mice lacking the osteoprotegerin gene, with and without 1 µg/kg/min of angiotensin II infusion for 14 days. Olmesartan treatment decreased systolic blood pressure, and echocardiography showed increased left ventricular systolic contractility. Three-dimensional micro-computed tomography scans demonstrated that olmesartan treatment increased trabecular bone volume (sham, +176%; angiotensin II infusion, +335%), mineral density (sham, +150%; angiotensin II infusion, +313%), and trabecular number (sham, +407%; angiotensin II infusion, +622%) in the tibia. Olmesartan increased cortical mineral density (sham, +19%; angiotensin II infusion, +24%), decreased the cortical bone section area (sham, -16%; angiotensin II infusion, -18%), decreased thickness (sham, -18%; angiotensin II infusion, -31%), and decreased the lacunar area (sham, -41%; angiotensin II infusion, -27%) in the tibia. Similar trend was observed in the femur. Moreover, olmesartan decreased angiotensin II-induced increases in tartrate-resistant acid phosphatase concentrations in plasma, but it affected neither type I procollagen N-terminal propeptides, nor the receptor activator of nuclear factor kappa-B ligand. Our data suggest that blockade of the angiotensin II type 1 receptor improves bone vulnerability, and helps to maintain the heart's structural integrity in osteoprotegerin-deficient mice.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Densidade Óssea/efeitos dos fármacos , Contração Miocárdica/efeitos dos fármacos , Osteíte Deformante/tratamento farmacológico , Osteíte Deformante/fisiopatologia , Disfunção Ventricular Esquerda/tratamento farmacológico , Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Animais , Pressão Sanguínea/efeitos dos fármacos , Modelos Animais de Doenças , Fêmur/efeitos dos fármacos , Fêmur/patologia , Fêmur/fisiopatologia , Hipertrofia/tratamento farmacológico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/metabolismo , Miocárdio/patologia , Osteíte Deformante/metabolismo , Osteíte Deformante/patologia , Fragmentos de Peptídeos/sangue , Pró-Colágeno/sangue , Ligante RANK/sangue , Sístole/efeitos dos fármacos , Sístole/fisiologia , Fosfatase Ácida Resistente a Tartarato/sangue
9.
Int J Pediatr Otorhinolaryngol ; 125: 82-86, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31271972

RESUMO

INTRODUCTION: Adenotonsillar hyperplasia (ATH) causing upper airway obstruction (UAO) may increase pulmonary artery systolic pressure (PASP). Early diagnosis and mouth breathing (MB) management may help in cases of high PASP. Total inspiratory nasal airflow (TINAF) obtained by active anterior rhinomanometry (AARM) is a means to quantify nasal patency. This study aimed to correlate TINAF with high PASP. METHODS: This is a prospective study involving 30 children between two and twelve years of age, with indication for adenotonsillectomy due to ATH, evaluated before and six months after surgery; and 29 nasal breathing (NB) children in the same age group. We obtained the PASP, calculated for tricuspid regurgitation, by means of a transthoracic echocardiography. We assessed nasal patency using the AARM to estimate the TINAF. RESULTS: The mean PASP among mouth breathing children was 25.99 mmHg, with a Standard Deviation of (±) 3.27, p = 0.01 in the preoperative period; and 21.79 mmHg (±2.48; p = 0.01) in the postoperative period. Among nasal breathers, this mean value was 21.64 mmHg (±3.87, p = 0.01). The mean pre-operative TINAF was 266.76 cm3/s (±112.21, p = 0.01); and 498.93 cm3/s (±137.80, p = 0.01) after surgery. Among nasal breathers it was 609.37 cm3/s (±109.16; p = 0.01). The mean nasal patency in the preoperative period was 42.85% (±17.83; p = 0.01); and 79.33% (±21.35; p = 0.01) in the post-op. Among nasal breathers it was 112.94% (±15.88, p = 0.01). There was a significant Spearman correlation value between TINAF and PASP (r = -0.459; p = 0.01) when we analyzed all the groups. CONCLUSION: PASP and TINAF values improved postoperatively and had an inverse correlation. This study suggests that by improving TINAF there was a decrease in PASP.


Assuntos
Adenoidectomia , Inalação/fisiologia , Respiração Bucal/cirurgia , Artéria Pulmonar/fisiologia , Tonsilectomia , Pressão Sanguínea/fisiologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Respiração Bucal/fisiopatologia , Estudos Prospectivos , Rinomanometria , Sístole/fisiologia
10.
Rev. clín. esp. (Ed. impr.) ; 219(5): 243-250, jun.-jul. 2019. ilus, tab, graf
Artigo em Espanhol | IBECS | ID: ibc-186558

RESUMO

Objetivo: La terapia de resincronización cardíaca (TRC) es una opción eficaz en el tratamiento de los pacientes con insuficiencia cardíaca y QRS ancho. Se ha demostrado que la presencia de un QRS fragmentado (QRS-f) en el electrocardiograma (ECG) de 12 derivaciones se asocia con una no respuesta a la TRC. El objetivo de este estudio es valorar si la aparición de la fragmentación (intervalo Q-f) es importante en la respuesta a la TRC. Métodos: Análisis retrospectivo de centro único de datos recogidos de manera prospectiva procedentes de 38 pacientes con miocardiopatía isquémica dilatada (18 hombres, media de edad de 63+/-12 años) sometidos a TRC con un QRS-f en ECG de 12 derivaciones. Se midieron la duración de la fragmentación, la relación duración del QRS-f/duración total del QRS (QRS-f/QRS-t) y el intervalo de tiempo transcurrido desde la aparición de la onda Q hasta el inicio de la fragmentación del QRS. Resultados: No se observaron diferencias estadísticamente significativas entre los pacientes respondedores (24 pacientes, 63%) y los no respondedores en cuanto a las características clínicas iniciales y los hallazgos electrocardiográficos. No obstante, en pacientes no respondedores a la TRC, se observó una mayor duración del QRS-f, una proporción QRS-f/QRS-t aumentada y un intervalo Q-f más breve. En el análisis multivariante, se estableció el intervalo Q-f como un predictor independiente de respuesta a la TRC (OR 1,240; IC 95%: 1,049-1,467; p=0,012). En el análisis de curva ROC, el valor de corte para el intervalo Q-f por lo que se refiere a la predicción de respondedores fue 32,5ms, con una sensibilidad y especificidad del 83,3 y 85,7%, respectivamente (AUC 0,899, IC 95%: 0,797-1,000; p=0,001). Conclusiones: Un intervalo de tiempo breve entre el inicio de QRS y el inicio de la fragmentación es un marcador ECG sencillo para la predicción de pacientes no respondedores a la TRC


Objective: Cardiac resynchronization therapy (CRT) is an effective option in the treatment of patients with heart failure and wide QRS. Presence of fragmented QRS (f-QRS) on 12-lead electrocardiogram (ECG) has been shown to be associated with non-response to CRT. The aim of this study was to evaluate whether onset of fragmentation (Q-f interval) is important for CRT response. Methods: This is a single-center retrospective analysis of prospectively collected data of 38 non-ischemic dilated cardiomyopathy patients (18 men, mean age 63+/-12 years) with f-QRS on 12-lead ECG who underwent CRT. Duration of fragmentation, ratio of f-QRS duration to the total QRS duration (f-QRS/t-QRS ratio) and time interval from Q wave to the onset of QRS fragmentation (Q-f interval) were measured. Results: The baseline clinical, echocardiographic findings of patients with responders (24 patients, 63%) and non-responders showed no statistically significant difference, except for longer f-QRS duration, increased ratio of f-QRS duration to the total QRS duration (f-QRS/t-QRS ratio) and shorter time interval from Q wave to the onset of QRS fragmentation (Q-f interval) in patients not responding to CRT. In multivariate analysis, Q-f interval was determined as an independent predictor of response to CRT (OR 1.240, 95% CI: 1.049-1.467, P=.012). In ROC curve analysis, the best cut-off value for Q-f interval to predict responders was 32.5ms with a sensitivity and specificity of 83.3% and 85.7%, respectively (AUC 0.899, 95% CI: 0.797-1.000, P=.001). Conclusions: Shorter time from onset of QRS to beginning of fragmentation is a simple ECG marker to predict non-responsive patients to CRT


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Terapia de Ressincronização Cardíaca/métodos , Insuficiência Cardíaca/terapia , Função Ventricular Esquerda/fisiologia , Sístole/fisiologia , Cardiomiopatia Dilatada/terapia , Valor Preditivo dos Testes , Recuperação de Função Fisiológica/fisiologia , Falha de Tratamento , Estudos Retrospectivos , Eletrocardiografia/estatística & dados numéricos
12.
BMC Res Notes ; 12(1): 271, 2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-31088530

RESUMO

OBJECTIVE: The risk of atherosclerotic cardiovascular disease (ASCVD) is estimated using the American College of Cardiology (ACC)/American Heart Association (AHA) Pooled Cohort Equations (PCEs). However, the accuracy of this tool remains controversial, particularly among patients who are recommended statin therapy according to the ACC/AHA guidelines. We performed external validation of PCEs among patients eligible for statin therapy using data from the systolic blood pressure intervention trial (SPRINT). RESULTS: Our study included 4057 patients from among the 9361 patients in SPRINT. The mean patient age was 64.5 years, and the median predicted 10-year risks of ASCVD were 17.2% and 12.3% for men and women, respectively. Over a median follow-up of 3.3 years, 133 primary events (including 23 cardiovascular deaths) were noted, whereas 304 events were predicted by the PCEs. The PCEs demonstrated poor calibration (Hosmer-Lemeshow test, p < 0.001) and overestimated the probability consistently. Additionally, they showed moderate discrimination [area under the curve: 0.65 (95% confidence interval, 0.60-0.69)]. This study demonstrates that PCEs might overestimate the risk of ASCVD in patients who are recommended statin therapy.


Assuntos
Pressão Sanguínea/fisiologia , Sístole/fisiologia , Aterosclerose/fisiopatologia , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
13.
Sensors (Basel) ; 19(9)2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31072052

RESUMO

Oscillometric blood pressure (BP) monitors currently estimate a single point but do not identify variations in response to physiological characteristics. In this paper, to analyze BP's normality based on oscillometric measurements, we use statistical approaches including kurtosis, skewness, Kolmogorov-Smirnov, and correlation tests. Then, to mitigate uncertainties, we use a deep learning method to determine the confidence limits (CLs) of BP measurements based on their normality. The proposed deep learning regression model decreases the standard deviation of error (SDE) of the mean error and the mean absolute error and reduces the uncertainties of the CLs and SDEs of the proposed technique. We validate the normality of the distribution of the BP estimation which fits the standard normal distribution very well. We use a rank test in the deep learning technique to demonstrate the independence of the artificial systolic BP and diastolic BP estimations. We perform statistical tests to verify the normality of the BP measurements for individual subjects. The proposed methodology provides accurate BP estimations and reduces the uncertainties associated with the CLs and SDEs using the deep learning algorithm.


Assuntos
Pressão Sanguínea/fisiologia , Aprendizado Profundo , Estatística como Assunto , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Criança , Diástole/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Reprodutibilidade dos Testes , Sístole/fisiologia , Adulto Jovem
14.
Neuroimage ; 199: 704-717, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31051292

RESUMO

Behavioral adaptations during performance rely on predicting and evaluating the consequences of our actions through action monitoring. Previous studies revealed that proprioceptive and exteroceptive signals contribute to error-monitoring processes, which are implemented in the posterior medial frontal cortex. Interestingly, errors also trigger changes in autonomic nervous system activity such as pupil dilation or heartbeat deceleration. Yet, the contribution of implicit interoceptive signals of bodily states to error-monitoring during ongoing performance has been overlooked. This study investigated whether cardiovascular interoceptive signals influence the neural correlates of error processing during performance, with an emphasis on the early stages of error processing. We recorded musicians' electroencephalography and electrocardiogram signals during the performance of highly-trained music pieces. Previous event-related potential (ERP) studies revealed that pitch errors during skilled musical performance are preceded by an error detection signal, the pre-error-negativity (preERN), and followed by a later error positivity (PE). In this study, by combining ERP, source localization and multivariate pattern classification analysis, we found that the error-minus-correct ERP waveform had an enhanced amplitude within 40-100 ms following errors in the systolic period of the cardiac cycle. This component could be decoded from single-trials, was dissociated from the preERN and PE, and stemmed from the inferior parietal cortex, which is a region implicated in cardiac autonomic regulation. In addition, the phase of the cardiac cycle influenced behavioral alterations resulting from errors, with a smaller post-error slowing and less perturbed velocity in keystrokes following pitch errors in the systole relative to the diastole phase of the cardiac cycle. Lastly, changes in the heart rate anticipated the upcoming occurrence of errors. This study provides the first evidence of preconscious visceral information modulating neural and behavioral responses related to early error monitoring during skilled performance.


Assuntos
Adaptação Fisiológica/fisiologia , Antecipação Psicológica/fisiologia , Eletroencefalografia/métodos , Potenciais Evocados/fisiologia , Função Executiva/fisiologia , Frequência Cardíaca/fisiologia , Interocepção/fisiologia , Lobo Parietal/fisiologia , Nível de Percepção Sonora/fisiologia , Desempenho Psicomotor/fisiologia , Sístole/fisiologia , Adulto , Diástole/fisiologia , Eletrocardiografia , Feminino , Humanos , Masculino , Música , Fatores de Tempo , Adulto Jovem
15.
Comput Methods Biomech Biomed Engin ; 22(8): 815-826, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30957542

RESUMO

Bicuspid aortic valve (BAV) aortopathy remains of difficult clinical management due to its heterogeneity and further assessment of related aortic hemodynamics is necessary. The aim of this study was to assess systolic hemodynamic indexes and wall stresses in patients with diverse BAV phenotypes and dilated ascending aortas. The aortic geometry was reconstructed from patient-specific images while the aortic valve was generated based on patient-specific measurements. Physiologic material properties and boundary conditions were applied and fully coupled fluid-structure interaction (FSI) analysis were conducted. Our dilated aortic models were characterized by the presence of abnormal hemodynamics with elevated degrees of flow skewness and eccentricity, regardless of BAV morphotype. Retrograde flow was also present. Both features, predicted by flow angle and flow reversal ratios, were consistently higher than those reported for non-dilated aortas. Right-handed helical flow was present, as well as elevated wall shear stress (WSS) on the outer ascending aortic wall. Our results suggest that the abnormal flow associated with BAV may play a role in aortic enlargement and progress it further on already dilated aortas.


Assuntos
Doenças da Aorta/fisiopatologia , Valva Aórtica/anormalidades , Doenças das Valvas Cardíacas/patologia , Doenças das Valvas Cardíacas/fisiopatologia , Hemodinâmica/fisiologia , Aorta/fisiologia , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/patologia , Valva Aórtica/fisiopatologia , Estudos de Casos e Controles , Dilatação Patológica , Doenças das Valvas Cardíacas/diagnóstico por imagem , Humanos , Modelos Cardiovasculares , Estresse Mecânico , Sístole/fisiologia
16.
Biomech Model Mechanobiol ; 18(5): 1351-1361, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30980211

RESUMO

The tricuspid leaflets coapt during systole to facilitate proper valve function and, thus, ensure efficient transport of deoxygenated blood to the lungs. Between their open state and closed state, the leaflets undergo large deformations. Quantification of these deformations is important for our basic scientific understanding of tricuspid valve function and for diagnostic or prognostic purposes. To date, tricuspid valve leaflet strains have never been directly quantified in vivo. To fill this gap in our knowledge, we implanted four sonomicrometry crystals per tricuspid leaflet and six crystals along the tricuspid annulus in a total of five sheep. In the beating ovine hearts, we recorded crystal coordinates alongside hemodynamic data. Once recorded, we used a finite strain kinematic framework to compute the temporal evolutions of area strain, radial strain, and circumferential strain for each leaflet. We found that leaflet strains were larger in the anterior leaflet than the posterior and septal leaflets. Additionally, we found that radial strains were larger than circumferential strains. Area strains were as large as 97% in the anterior leaflet, 31% in the posterior leaflet, and 31% in the septal leaflet. These data suggest that tricuspid valve leaflet strains are significantly larger than those in the mitral valve. Should our findings be confirmed they could suggest either that the mechanobiological equilibrium of tricuspid valve resident cells is different than that of mitral valve resident cells or that the mechanotransductive apparatus between the two varies. Either phenomenon may have important implications for the development of tricuspid valve-specific surgical techniques and medical devices.


Assuntos
Coração/fisiopatologia , Contração Miocárdica/fisiologia , Valva Tricúspide/fisiopatologia , Animais , Fenômenos Biomecânicos , Hemodinâmica , Ovinos , Estresse Mecânico , Sístole/fisiologia , Fatores de Tempo
17.
Med Sci Sports Exerc ; 51(9): 1838-1844, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30973478

RESUMO

PURPOSE: At the onset of physical exercise, oxygen (O2) transport adapts to meet the working muscle O2 demands. Cardiac output abruptly increases through the concomitant changes of HR and stroke volume (SV), which is conditioned by the left ventricular (LV) function. The purpose of this study was to investigate the contribution of many LV diastolic and systolic function parameters, including twist-untwist mechanics, to SV adaptation during the first minutes after exercise onset. METHODS: Diastolic and systolic myocardial strains and twist were monitored by two-dimensional speckle-tracking echocardiography with high temporal resolution in 28 young men (mean age, 23 ± 4 yr) who performed five similar constant work-load exercises on a cycloergometer (target HR: 125 bpm). Two-dimensional cine-loops were recorded every 15 s during the first minute of exercise, and then every 30 s for the next 3 min. RESULTS: During the first 60 s of exercise, SV (from 104 ± 15 mL to 126 ± 21 mL, P < 0.001) increased concomitantly with LV strain and strain rates. Early filling was the main SV determinant during this phase, probably linked to the increase of venous return (at the very beginning of exercise), LV relaxation (from 1.5 ± 0.3 s to 2.5 ± 0.4 s, P < 0.001) and untwisting (from -78 ± 34°·s to -165 ± 61°·s, P < 0.001). After the first minute, SV remained constant, whereas LV untwisting continued to increase (from -165 ± 61°·s to -187 ± 60°·s, P < 0.001) and the other systolic and diastolic parameters reached a plateau. CONCLUSIONS: This study gives new mechanical insights into LV kinetics to address the challenge of SV response at the onset of exercise.


Assuntos
Exercício/fisiologia , Descanso/fisiologia , Função Ventricular Esquerda/fisiologia , Adaptação Fisiológica , Adolescente , Adulto , Diástole/fisiologia , Ecocardiografia , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Volume Sistólico/fisiologia , Sístole/fisiologia , Adulto Jovem
18.
Monaldi Arch Chest Dis ; 89(1)2019 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-30968664

RESUMO

The echocardiographic evaluation of left ventricular (LV) systolic function, and especially of ejection fraction (EF) plays a central role in the diagnosis of heart failure (HF) due to its undisputed prognostic value. Limitations of EF are substantially: i) the variability and reproducibility of measurements, and ii) the load-dependence. Measurement of stroke volume, longitudinal function and myocardial strain can overcome the limitations of EF in assessing the contractile reserve of patients with HF and may help to define both the phenotype and prognosis of the disease. The recognition of diastolic dysfunction (mainly by echocardiography) is the pathophysiological basis to make diagnosis of HF with preserved ejection fraction (HFpEF). The limitations are essentially related to its feasibility, since performing a multi-parametric quantitative echocardiographic evaluation, as indicated by the guidelines, may be difficult in clinical practice. Difficulties in method standardization, the poor attitude of cardiologists to test their reproducibility (test-retest, variability) favor the evaluation "at-a-glance" of LV structural and functional LV abnormalities.


Assuntos
Insuficiência Cardíaca/diagnóstico por imagem , Volume Sistólico/fisiologia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Ecocardiografia/métodos , Insuficiência Cardíaca/fisiopatologia , Humanos , Prognóstico , Reprodutibilidade dos Testes , Sístole/fisiologia , Disfunção Ventricular Esquerda/fisiopatologia , Função Ventricular Esquerda/fisiologia
19.
Comput Methods Biomech Biomed Engin ; 22(7): 752-763, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30880461

RESUMO

OBJECTIVES: This study aims to examine the alteration in coronary haemodynamics with increasing the severity of vessel compression caused by myocardial bridging (MB). METHODS: Angiography and intravascular ultrasound were performed in 10 patients with MB with varying severities of systolic compression in the left anterior descending (LAD) artery. Computer models of MB were developed and transient computational fluid dynamics simulations were performed to derive distribution of blood residence time and shear stress. RESULTS: With increasing the severity of bridge compression, a decreasing trend was observed in the shear stress over proximal segment whereas an increasing trend was found in the shear stress over bridge segment. When patients were divided into 2 groups based on the average systolic vessel compression in the whole cohort (%CRave = 27.38), patients with bridges with major systolic compression (>%CRave) had smaller shear stress and higher residence time in the proximal segment compared to those with bridges with minor systolic compression (<%CRave) (0.37 ± 0.23 vs 0.69 ± 0.29 Pa and 0.0037 ± 0.0069 vs 0.022 ± 0.0094 s). In contrast, patients with bridges with major systolic compression had greater shear stress in the bridge segment compared to those with bridges with minor systolic compression (2.49 ± 2.06 vs 1.13 ± 0.89 Pa). No significant difference was found in the distal shear stress of patients with bridges with major and minor systolic compression. CONCLUSION: Our findings revealed a direct relationship between the severity of systolic compression of MB and haemodynamic perturbations in the proximal segment such that the increased systolic vessel compression was associated with decreased shear stress and increased blood residence time.


Assuntos
Hemodinâmica/fisiologia , Ponte Miocárdica/fisiopatologia , Pressão Sanguínea , Angiografia Coronária , Diástole/fisiologia , Feminino , Humanos , Hidrodinâmica , Masculino , Pessoa de Meia-Idade , Ponte Miocárdica/diagnóstico por imagem , Miocárdio/patologia , Sístole/fisiologia , Fatores de Tempo
20.
Medicine (Baltimore) ; 98(13): e15070, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30921240

RESUMO

Echocardiography and cardiac biomarkers, such as cardiac troponin I (cTnI) and N-terminal pro-B-type natriuretic peptide (NT-pro BNP) are useful tools to evaluate cardiac dysfunction. Left ventricular systolic dysfunction (LVSD) is common in pediatric severe sepsis. The aim of this study is to evaluate the prognostic value of LVSD, cTnI, and NT-pro BNP for pediatric severe sepsis.A prospective, single center, observational study was conducted. Severe sepsis children were enrolled in the study from December 2015 to December 2016 in pediatric intensive care unit of Shanghai Children's Medical Center. Recorded general information, transthoracic echocardiography were performed at day 1, 2, 3, 7, and 10, using Simpson to measure left ventricular end-diastolic dimension and left ventricular end-systolic dimension, obtained echocardiography parameters: left ventricular ejection fraction (LVEF), left ventricular fractional shortening, left ventricular end-diastolic volume, left ventricular end- systolic volume, stroke volume, cardiac output. At the same time collecting the blood sample to measure cTnI, NT-pro BNP. The definition of LVSD was LVEF <50%. According to the prognosis of 28 days, children with severe sepsis were divided into survived group and nonsurvived group.Total of 50 pediatric patients who were diagnosed with severe sepsis (including septic shock) were enrolled, the incidence of LVSD was 52%. The 28-day mortality rate of severe sepsis was 34%. Multivariate logistic regression analyses for predictors of death in pediatric severe sepsis revealed that the 28-day mortality of severe sepsis was associated with mechanical ventilation (MV) within the first 6 hours of admission (odds ratio [OR], 0.01; 95% confidence interval [CI], 0.00-0.07) and total MV time (OR, 0.81; 95% CI, 0.68-0.97). The receiver operating characteristic curves LVEF (area under curve = 0.526), cTnI (area under curve = 0.480), and NT-pro BNP (area under curve = 0.624) were used to predict the 28-day mortality in pediatric severe sepsis. Follow-up echocardiography parameters for survived group and nonsurvived group showed no significant changes in LVEF, LVFS, stroke volume index, cardiac index (CI), left ventricular end-diastolic volume index and left ventricular end-systolic volume index at day 1, 2, 3, 7, and 10, except for CI at day 1 and 2. Kaplan-Meier plot of 28-day mortality and LVSD in pediatric severe sepsis showed there were no statistical differences (χ = 0.042, P = .837).LVSD occurs frequently in pediatric with severe sepsis. The 28-day mortality rate of severe sepsis was also high. In this study, none of LVSD, cTnI, and NT-proBNP was associated with the prognosis of pediatric severe sepsis.


Assuntos
Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Sepse/mortalidade , Troponina I/sangue , Disfunção Ventricular Esquerda/mortalidade , Função Ventricular Esquerda/fisiologia , Biomarcadores/sangue , Criança , Pré-Escolar , Ecocardiografia/estatística & dados numéricos , Feminino , Mortalidade Hospitalar , Humanos , Modelos Logísticos , Masculino , Análise Multivariada , Prognóstico , Estudos Prospectivos , Sepse/sangue , Sepse/fisiopatologia , Sístole/fisiologia , Disfunção Ventricular Esquerda/etiologia
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