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1.
Article in Chinese | WPRIM | ID: wpr-879251

ABSTRACT

Right ventricular (RV) failure has become a deadly complication of left ventricular assist device (LVAD) implantation, for which desynchrony in bi-ventricular pulse resulting from a LVAD is among the important factor. This paper investigated how different control modes affect the synchronization of pulse between LV (left ventricular) and RV by numerical method. The numerical results showed that the systolic duration between LV and RV did not significantly differ at baseline (LVAD off and cannula clamped) (48.52%


Subject(s)
Heart Failure/therapy , Heart-Assist Devices , Humans , Systole , Ventricular Dysfunction, Right , Ventricular Function, Right
2.
Rev. bras. cir. cardiovasc ; 35(1): 117-119, Jan.-Feb. 2020. tab, graf
Article in English | LILACS | ID: biblio-1092476

ABSTRACT

Abstract Congenital mitral valve stenosis is a rare and severe disease, usually associated with other heart defects. The appropriate intervention depends on the site and mechanism of valvular obstruction and the aim is to avoid or delay valve replacement since it is associated with significant morbidity and mortality. Early single-stage complete repair is associated with better prognosis. We report the case of a 20-month-old child with a supravalvar mitral ring combined with a ventricular septal defect; pulmonary arterial systolic pressure before the surgery was 79 mmHg. The patient underwent a successful surgical repair with good clinical resolution.


Subject(s)
Humans , Infant , Heart Defects, Congenital , Heart Septal Defects, Ventricular , Mitral Valve Stenosis , Prognosis , Systole
4.
Article in English | WPRIM | ID: wpr-812991

ABSTRACT

OBJECTIVES@#To study myocardial perfusion and systolic function in patients with different coronary artery stenosis by myocardial contrast echocardiography (MCE) and two-dimensional speckle tracking imaging (2D-STI).@*METHODS@#MCE, 2D-STI and coronary angiography were conducted in patients with coronary heart disease in our hospital. Myocardial segments were divided into 4 groups according to the degree of coronary artery stenosis: group A (normal group), group B (mild stenosis, 50%-75%), group C (moderate stenosis, 76%-90%) and group D (severe stenosis, 91%-100%). Blood volume, blood flow velocity, blood flow and longitudinal myocardial strain value (SL) in each group were measured by analysis software for MCE and 2D-STI. The differences in blood volume, blood flow velocity, blood flow and SL were evaluated.@*RESULTS@#The blood flow velocity and blood flow in B, C and D groups were decreased gradually, with significant difference (0.05). There were significant differences in SL among the 4 groups (<0.05).@*CONCLUSIONS@#There is a good correlation between coronary stenosis degree and myocardial perfusion or systolic function. The ability of 2D-STI to detect mild stenosis of coronary artery is better than MCE.


Subject(s)
Coronary Circulation , Coronary Stenosis , Echocardiography , Humans , Myocardium , Systole
5.
Rev. bras. cir. cardiovasc ; 34(4): 451-457, July-Aug. 2019. tab, graf
Article in English | LILACS | ID: biblio-1020508

ABSTRACT

Abstract 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.


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged , Aorta/physiopathology , Magnetic Resonance Imaging , Aortic Aneurysm, Thoracic/diagnostic imaging , Aneurysm, Dissecting/diagnostic imaging , Systole/physiology , Diastole/physiology , Dilatation, Pathologic , Elasticity
6.
Rev. salud pública Parag ; 9(1): [P57-P64], jun. 2019.
Article in Spanish | LILACS, BDNPAR | ID: biblio-1047032

ABSTRACT

Introducción: La dilatación de la aurícula izquierda (AI) se considera un marcador ecocardiográfico para la remodelación auricular y la fibrilación auricular. Por ende, hemos investigado la correlación entre la dilatación de la AI con las alteraciones hemodinámicas del ventrículo izquierdo en pacientes con hipertensión arterial. Objetivo: Determinar la relación existente entre la hipertensión arterial y la dilatación auricular izquierda. Así mismo determinar las características epidemiológicas de la población en estudio y las diferencias ecocardiográficas entre pacientes hipertensos y pacientes sin HTA. Metodología: En este estudio observacional y prospectivo hemos investigado las variaciones electrocardiográficas, mediciones ecocardiográficas y Holter ECG de 24 hs en pacientes hipertensos que acuden a un hospital terciario desde marzo a septiembre del 2018 en forma ambulatoria y a internados en el Hospital de Clínicas. Resultados: Se estudiaron 104 pacientes, 65 hipertensos conocidos y 39 no hipertensos como grupo control. El diámetro de la AI tuvo una media de 37±8 en pacientes hipertensos, mientras que en pacientes no hipertensos la media fue de 34±5 (p=0,03). Se encontró una asociación significativa entre hipertensión y aumento del diámetro de la AI (p=0,04 OR: 2,6 IC 0,88­7,7). En los pacientes hipertensos se observó una asociación significativa entre la aurícula izquierda dilatada y la fracción de eyección disminuida (p= 0,01 OR: 4,66 IC: 1,28­16,98). Además, una asociación significativa entre la AI dilatada y el diámetro diastólico aumentado del ventrículo izquierdo (VI) (p= 0,0004 OR: 8,75 IC 2,18­35,01). Se observó una asociación significativa entre la presencia de una AI dilatada y el diámetro sistólico del VI aumentado en hipertensos (p= 0,006 OR: 5,74 IC 1,5­21,91). Conclusiones: Hubo una relación significativa entre la hipertensión arterial y la dilatación de la aurícula izquierda. Los pacientes hipertensos con una dilatación de la AI tuvieron un aumento significativo de los diámetros sistólicos y diastólicos del ventrículo izquierdo, así como una disminución significativa de la funcionalidad sistólica del ventrículo izquierdo. Por ende, los pacientes hipertensos que tienen una dilatación de la aurícula izquierda presentaron además alteraciones hemodinámicas asociadas del ventrículo izquierdo. Palabras clave: Dilatación de la aurícula izquierda; Hipertensión arterial; Fracción de eyección del VI. Diámetro sistólico y diastólico del VI.


Introduction: Dilation of the left atrium (LA) is considered an echocardiographic marker for atrial remodeling and atrial fibrillation. Therefore, we have investigated the correlation between dilatation of the IA with hemodynamic alterations of the left ventricle in patients with arterial hypertension. Objetive: Determine the relationship between arterial hypertension and left atrial dilatation. The same epidemiological characteristics of the study population and the echocardiographic differences between hypertensive patients and patients without HTN. Methodology: In this observational and prospective study we have investigated electrocardiographic variations, echocardiographic measurements and Holter ECG of 24 hours in hypertensive patients who attend a tertiary hospital from March 2018 to September 2018 as outpatients and inpatients. Results: 104 patients were studied, 65 known hypertensive patients and, 39 non-hypertensive as control group. The diameter of the AI had a mean of 37 ± 8 in hypertensive patients, while in non-hypertensive patients the mean was 34 ± 5 (p = 0.03). A significant association was found between hypertension and increased diameter of the LA (p = 0.04 OR: 2.6 CI 0.88-7.7). In hypertensive patients, a significant association was observed between the dilated left atrium and the decreased ejection fraction (p = 0.01 OR: 4.66 CI: 1.28- 16.98). In addition, a significant association between dilated LA and the increased diastolic diameter of the LV (p = 0.0004 OR: 8.75 IC 2.18-35.01). A significant association was observed between the presence of dilated IA and the left ventricular systolic diameter increased in hypertensive patients (p = 0.006 OR: 5.74 CI 1.5-21.91). Conclusion: There was a significant relationship between arterial hypertension and dilatation of the left atrium. Hypertensive patients with dilatation of the IA had a significant increase in systolic and diastolic diameters of the left ventricle, as well as a significant decrease in systolic functionality of the left ventricle. Therefore, hypertensive patients who have dilation of the left atrium also had associated hemodynamic alterations of the left ventricle. Key words: Dilation of the left atrium; Arterial hypertension; LV ejection fraction. Systolic and diastolicdiameter of the LV.


Subject(s)
Humans , Male , Female , Atrial Function, Left , Hypertension , Systole , Diastole
7.
Article in English | WPRIM | ID: wpr-758946

ABSTRACT

Unenhanced echocardiography (UE), commonly used in veterinary practice, is limited by left ventricular (LV) foreshortening and observer dependency. Contrast echocardiography (CE) was used to compare two-dimensional (2D) LV measurements made using UE and 256-row multi-detector computed tomography (MDCT) as a reference standard. Seven healthy beagle dogs were evaluated in this study. Measurements obtained using CE, including LV wall thickness, internal diameter, and longitudinal and transverse length, were significantly greater than those obtained using UE. Measurements of LV internal dimension in diastole (LVIDd) and systole (LVIDs) were significantly larger with CE compared UE. Regardless of the cardiac cycle, LV longitudinal (LVLd and LVLs) and transverse diameter (LVTDd and LVTDs) measurements were significantly different with CE and approximated values from MDCT. Among automatically calculated parameters, LV end-systolic volume and the relative wall thickness were significantly different between UE and CE. In CE, the correlation coefficients of 4 major parameters (r = 0.87 in LVIDd; 0.91 in LVIDs; 0.87 in LVLd; and 0.81 in LVLs) showed higher values compared to the UE (r = 0.68 in LVIDd, 0.71 in LVIDs, 0.69 in LVLd, and 0.35 in LVLs). Inter-observer agreement was highest for MDCT and higher for CE than UE. In conclusion, CE is more accurate and reproducible than UE in assessing 2D LV measurements and can overcome the limitations of UE including LV foreshortening and high observer dependency.


Subject(s)
Animals , Diastole , Dogs , Echocardiography , Multidetector Computed Tomography , Systole
10.
Arch. endocrinol. metab. (Online) ; 62(4): 392-398, July-Aug. 2018. tab
Article in English | LILACS | ID: biblio-950084

ABSTRACT

ABSTRACT Objective: Treatment of subclinical hypothyroidism (ScH), especially the mild form of ScH, is controversial because thyroid hormones influence cardiac function. We investigate left ventricular systolic and diastolic function in ScH and evaluate the effect of 5-month levothyroxine treatment. Subjects and methods: Fifty-four patients with newly diagnosed mild ScH (4.2 <TSH < 10.0 mU/L) and 30 euthyroid subjects matched by age were analysed. Laboratory analyses and an echocardiography study were done at the first visit and after 5 months in euthyroid stage in patients with ScH. Results: Compared to healthy controls, patients with ScH had a lower E/A ratio (1.03 ± 0.29 vs. 1.26 ± 0.36, p < 0.01), higher E/e' sep. ratio (762 ± 2.29 vs. 6.04 ± 1.64, p < 0.01), higher myocardial performance index (MPI) (0.47 ± 0.08 vs. 0.43 ± 0.07, p < 0.05), lower global longitudinal strain (GLS) (-19.5 ± 2.3 vs. −20.9 ± 1.7%, p < 0.05), and lower S wave derived by tissue Doppler imaging (0.077 ± 0.013 vs. 0.092 ± 0.011 m/s, p < 0.01). Levothyroxine treatment in patients with ScH contributed to higher EF (62.9 ± 3.9 vs. 61.6 ± 4.4%, p < 0.05), lower E/e' sep. ratio (6.60 ± 2.06 vs. 762 ± 2.29, p < 0.01), lower MPI (0.43 ± 0.07 vs. 0.47 ± 0.08%, p < 0.01), and improved GLS (-20.07 ± 2.7 vs. −19.55 ± 2.3%, p < 0.05) compared to values in ScH patients at baseline. Furthermore, in all study populations (ScH patients before and after levothyroxine therapy and controls), TSH levels significantly negatively correlated with EF (r = −0.15, p < 0.05), E/A (r = −0.14, p < 0.05), GLS (r = −0.26, p < 0.001), and S/TDI (r = −0.22, p < 0.01) and positively correlated with E/e' sep. (r = 0.14, p < 0.05). Conclusion: Patients with subclinical hypothyroidism versus healthy individuals had subtle changes in certain parameters that indicate involvement of systolic and diastolic function of the left ventricle. Although the values of the parameters were in normal range, they were significantly different compared to ScH and the control group at baseline, as well as to the ScH groups before and after treatment.The results of our study suggest that patients with ScH must be followed up during treatment to assess improvement of the disease. Some of the echocardiography obtained parameters were reversible after levothyroxine therapy.


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Systole/drug effects , Thyroxine/pharmacology , Ventricular Function, Left/drug effects , Diastole/drug effects , Hypothyroidism/drug therapy , Systole/physiology , Thyroxine/administration & dosage , Thyroxine/blood , Thyroxine/therapeutic use , Triiodothyronine/blood , Thyrotropin/blood , Case-Control Studies , Prospective Studies , Echocardiography, Doppler, Pulsed , Diastole/physiology , Heart Ventricles/physiopathology , Heart Ventricles/diagnostic imaging
11.
Arq. bras. cardiol ; 110(4): 373-380, Apr. 2018. tab, graf
Article in English | LILACS | ID: biblio-888046

ABSTRACT

Abstract Background: Physical exercise should be part of the treatment of post-acute myocardial infarction (AMI) patients. Objective: To evaluate the effects of two training prescription models (continuous x interval) and its impact on ventricular function in rats after AMI with normal ventricular function. Methods: Forty Wistar rats were evaluated by echocardiography 21 days after the AMI. Those with LVEF = 50% (n = 29) were included in the study and randomized to control group (CG n = 10), continuous training group (CTG n = 9) or interval training group (ITG, n = 10). Then, a swimming test with control of lactate production was performed. Based on its result, the lactate threshold (LT) was established to define the training intensities. After six weeks, the animals were reassessed by echocardiography and lactate production. Outcome measures were end-diastolic diameter (EDD), end-systolic diameter (ESD), left ventricular ejection fraction (LVEF, %) lactate at rest, lactate without overload, and lactate with 12g and 13.5g of additional load. Group comparisons of quantitative variables of the study were performed by one-factor analysis of variance (ANOVA). The Newman-Keuls test was used for multiple comparisons of the groups. Within-group comparisons of dependent variables between the two training protocols were performed by Student's t-test. Normality of the variables was tested by the Shapiro-Wilks test. Values of p < 0.05 indicated statistical significance. Results: EDD, ESD, and LVEF before and after the training period were similar in within-group comparisons. However, EDD was significantly different (p=0.008) in the CG. Significant differences were found for L12g (p=0.002) and L13.5g (p = 0.032) in the ITG, and for L12g (p = 0.014) in the CG. No differences were found in the echocardiographic parameters between the groups. Significant differences were found in lactate without overload (p = 0.016) and L12 (p = 0.031) in the second assessment compared with the first, and between the groups - ITG vs. CG (p = 0.019) and CTG vs. CG (p = 0.035). Conclusion: Both methods produced a training effect without altering ventricular function.


Resumo Fundamento: O exercício físico deve fazer parte do tratamento de pacientes pós-infarto agudo do miocárdio (IAM). Objetivo: Avaliar os efeitos de treinamento produzidos por dois modelos distintos (contínuo x intervalado) e sua repercussão sobre a função ventricular de ratos pós-IAM com função ventricular normal. Métodos: Quarenta ratos Wistar pós-IAM foram avaliados ecocardiograficamente 21 dias após o evento. Aqueles com FEVE = 50% (n = 29) foram incluídos e randomizados: controle (GC n = 10), treinamento contínuo (GTC n = 9) e treinamento intervalado (GTI n = 10). Após, foi realizado um teste de natação com controle de lactato. A partir do resultado foi definido o limiar de lactato (LL) para determinar as intensidades do treinamento. Após seis semanas, foram reavaliados com ecocardiografia e controle de lactato. Como desfecho, foram avaliados: diâmetros diastólico e sistólico final (DDF, DSF, mL), fração de ejeção do ventrículo esquerdo (FEVE, %), lactato de repouso, livre de carga (LC), lactato com 12 g e 13,5 g de carga adicional. Para a comparação dos grupos em relação às variáveis quantitativas do estudo, foi considerado o modelo de análise da variância com um fator (ANOVA). Nas comparações múltiplas dos grupos foi usado o teste de Newman-Keuls. Na comparação entre as duas avaliações, dentro de cada grupo, foi usado o teste t de Student para amostras dependentes. A condição de normalidade das variáveis foi avaliada pelo teste de Shapiro-Wilks. Valores de p < 0,05 indicaram significância estatística. Resultados: Com relação à análise intragrupos, entre o período pré- e pós-treinamento foi identificado semelhança para DDF, DSF, FEVE, porém o GC apresentou diferença significativa para a variável DDF (p = 0,008). Houve diferença do GTI para L12g (p = 0,002) e L13,5g (p = 0,032) e para o GTC na variável L12g (p = 0,014). Não houve diferença para as variáveis ecocardiográficas entre os grupos. Houve diferença nas variáveis LC e L12g na segunda avaliação (p = 0,016 e p = 0,031, respectivamente) e entre os grupos: GTI vs. GC (p = 0,019) e GTC vs. GC (p = 0,035). Conclusão: Os dois métodos produziram efeito de treinamento sem alterar a função ventricular.


Subject(s)
Animals , Male , Physical Conditioning, Animal/methods , Ventricular Function, Left/physiology , High-Intensity Interval Training/methods , Myocardial Infarction/physiopathology , Reference Values , Stroke Volume/physiology , Swimming/physiology , Systole/physiology , Time Factors , Echocardiography , Random Allocation , Treatment Outcome , Rats, Wistar , Lactic Acid/blood , Diastole/physiology , Exercise Test/methods , Myocardial Infarction/diagnostic imaging
12.
Arq. bras. cardiol ; 110(3): 231-239, Mar. 2018. tab, graf
Article in English | LILACS | ID: biblio-888029

ABSTRACT

Abstract Background: Despite significant advances in understanding the pathophysiology and management of asthma, some of systemic effects of asthma are still not well defined. Objectives: To compare heart function, baseline physical activity level, and functional exercise capacity in young patients with mild-to-moderate asthma and healthy controls. Methods: Eighteen healthy (12.67 ± 0.39 years) and 20 asthmatics (12.0 ± 0.38 years) patients were enrolled in the study. Echocardiography parameters were evaluated using conventional and tissue Doppler imaging (TDI). Results: Although pulmonary acceleration time (PAT) and pulmonary artery systolic pressure (PASP) were within normal limits, these parameters differed significantly between the control and asthmatic groups. PAT was lower (p < 0.0001) and PASP (p < 0.0002) was higher in the asthma group (114.3 ± 3.70 ms and 25.40 ± 0.54 mmHg) than the control group (135.30 ± 2.28 ms and 22.22 ± 0.40 mmHg). The asthmatic group had significantly lower early diastolic myocardial velocity (E', p = 0.0047) and lower E' to late (E'/A', p = 0.0017) (13.75 ± 0.53 cm/s and 1.70 ± 0.09, respectively) compared with control group (15.71 ± 0.34 cm/s and 2.12 ± 0.08, respectively) at tricuspid valve. In the lateral mitral valve tissue Doppler, the asthmatic group had lower E' compared with control group (p = 0.0466; 13.27 ± 0.43 cm/s and 14.32 ± 0.25 cm/s, respectively), but there was no statistic difference in the E'/A' ratio (p = 0.1161). Right isovolumetric relaxation time was higher (p = 0.0007) in asthmatic (57.15 ± 0.97 ms) than the control group (52.28 ± 0.87 ms), reflecting global myocardial dysfunction. The right and left myocardial performance indexes were significantly higher in the asthmatic (0.43 ± 0.01 and 0.37 ± 0.01, respectively) compared with control group (0.40 ± 0.01 and 0.34 ± 0.01, respectively) (p = 0.0383 and p = 0.0059, respectively). Physical activity level, and distance travelled on the six-minute walk test were similar in both groups. Conclusion: Changes in echocardiographic parameters, evaluated by conventional and TDI, were observed in mild-to-moderate asthma patients even with normal functional exercise capacity and baseline physical activity level. Our results suggest that the echocardiogram may be useful for the early detection and evoluation of asthma-induced cardiac changes.


Resumo Fundamento: Apesar de avanços significativos no entendimento da fisiopatologia e manejo da asma, alguns efeitos sistêmicos da asma ainda não são bem definidos. Objetivos: Comparar a função cardíaca, o nível de atividade física basal, e a capacidade funcional de pacientes jovens com asma leve a moderada com controles saudáveis. Métodos: Dezoito voluntários saudáveis (12,67 ± 0,39 anos) e 20 pacientes asmáticos (12,0 ± 0,38 anos) foram incluídos no estudo. Os parâmetros de ecocardiografia foram avaliados pelo exame de ecocardiogragia com Doppler convencional e tecidual (EDT). Resultados: Apesar de o tempo de aceleração pulmonar (TAP) e da pressão arterial sistólica pulmonar (PASP) encontrarem-se dentro da faixa de normalidade, esses parâmetros foram significativamente diferentes entre o grupo controle e o grupo asmático. O TAP foi menor (p < 0,0001) e a PASP maior (p < 0,0002) no grupo de indivíduos asmáticos (114,3 ± 3,70 ms e 25,40 ± 0,54 mmHg) que o grupo controle (135,30 ± 2,28 ms e 22,22 ± 0,40 mmHg). O grupo asmático apresentou velocidade diastólica inicial do miocárdio (E', p = 0,0047) e relação entre E' e velocidade tardia mais baixas (E'/A', p = 0,0017) (13,75 ± 0,53 cm/s e 1,70 ± 0,09, respectivamente) em comparação ao grupo controle (15,71 ± 0,34 cm/s e 2,12 ± 0,08, respectivamente) na valva tricúspide. No exame Doppler tecidual do anel mitral lateral, o grupo asmático apresentou menor E' em comparação ao grupo controle (p = 0,0466; 13,27 ± 0,43 cm/s e 14,32 ± 0,25 cm/s, respectivamente), mas não houve diferença estatística na razão E'/A' (p = 0,1161). O tempo de relaxamento isovolumétrico foi maior no grupo de pacientes asmáticos (57,15 ± 0,97 ms) que no grupo controle (52,28 ± 0,87 ms) (p = 0,0007), refletindo uma disfunção global do miocárdio. O índice de performance miocárdica direito e esquerdo foi significativamente maior no grupo asmático (0,43 ± 0,01 e 0,37 ± 0,01, respectivamente) que no grupo controle (0,40 ± 0,01 e 0,34 ± 0,01, respectivamente) (p = 0,0383 e p = 0,0059 respectivamente). O nível de atividade física e a distância percorrida no teste de caminhada de seis minutos foram similares entre os grupos. Conclusão: Mudanças nos parâmetros ecocardiográficos, avaliados pela ecocardiografia convencional e pela EDT foram observadas em pacientes com asma moderada a grave com capacidade funcional e nível de atividade física basal normais. Nossos resultados sugerem que o ecocardiograma pode ser útil para a detecção precoce e a evolução de alterações cardíacas induzidas pela asma. (Arq Bras Cardiol. 2018; 110(3):231-239)


Subject(s)
Humans , Male , Female , Child , Adolescent , Asthma/physiopathology , Exercise/physiology , Ventricular Function/physiology , Exercise Tolerance/physiology , Quality of Life , Reference Values , Respiratory Function Tests/methods , Systole/physiology , Time Factors , Severity of Illness Index , Case-Control Studies , Surveys and Questionnaires , Ventricular Dysfunction/physiopathology , Ventricular Dysfunction/diagnostic imaging , Statistics, Nonparametric , Echocardiography, Doppler, Pulsed/methods , Diastole/physiology , Exercise Test/methods
13.
Chinese Medical Journal ; (24): 1834-1839, 2018.
Article in English | WPRIM | ID: wpr-773968

ABSTRACT

Background@#Pressure overload-induced myocardial hypertrophy is a key step leading to heart failure. Previous cellular and animal studies demonstrated that deteriorated excitation-contraction coupling occurs as early as the compensated stage of hypertrophy before the global decrease in left ventricular ejection fraction (LVEF). This study was to evaluate the cardiac electromechanical coupling time in evaluating cardiac systolic function in the early stage of heart failure.@*Methods@#Twenty-six patients with Stage B heart failure (SBHF) and 31 healthy controls (CONs) were enrolled in this study. M-mode echocardiography was performed to measure LVEF. Tissue Doppler imaging (TDI) combined with electrocardiography (ECG) was used to measure cardiac electromechanical coupling time.@*Results@#There was no significant difference in LVEF between SBHF patients and CONs (64.23 ± 8.91% vs. 64.52 ± 5.90%; P = 0.886). However, all four electromechanical coupling time courses (Qsb: onset of Q wave on ECG to beginning of S wave on TDI, Qst: onset of Q wave on ECG to top of S wave on TDI, Rsb: top of R wave on ECG to beginning of S wave on TDI, and Rst: top of R wave on ECG to top of S wave on TDI) of SBHF patients were significantly longer than those of CONs (Qsb: 119.19 ± 35.68 ms vs. 80.30 ± 14.81 ms, P < 0.001; Qst: 165.42 ± 60.93 ms vs. 129.04 ± 16.97 ms, P = 0.006; Rsb: 82.43 ± 33.66 ms vs. 48.30 ± 15.18 ms, P < 0.001; and Rst: 122.37 ± 36.66 ms vs. 93.25 ± 16.72 ms, P = 0.001), and the Qsb, Rsb, and Rst time showed a significantly higher sensitivity than LVEF (Rst: P =0.032; Rsb: P = 0.003; and Qsb: P = 0.004).@*Conclusions@#The cardiac electromechanical coupling time is more sensitive than LVEF in evaluating cardiac systolic function.


Subject(s)
Adult , Echocardiography , Echocardiography, Doppler , Electrocardiography , Female , Humans , Male , Middle Aged , Systole , Ventricular Function, Left
14.
Neonatal Medicine ; : 1-6, 2018.
Article in English | WPRIM | ID: wpr-741660

ABSTRACT

Extremely low birth weight infants remain at increased risk of intraventricular hemorrhage from the fragile vascular bed of the germinal matrix; the roles of hypotension (ischemia) and reperfusion (hyperemia) in the development of intraventricular hemorrhage are still debated. Cerebrovascular pressure autoregulation protects the brain by maintaining constant cerebral blood flow despite changes in blood pressure. The ontogeny of cerebrovascular pressure autoregulation has not been well established and uncertainty remains about the optimal arterial blood pressure required to support brain perfusion. Another important aspect of premature cerebral hemodynamics is the critical closing pressure––the arterial blood pressure at which cerebral blood flow ceases. Interestingly, in premature infants, the critical closing pressure approximates the mean arterial blood pressure. Often in this unique population, cerebral blood flow occurs only during systole when the diastolic arterial blood pressure is equal to the critical closing pressure. Moreover, the diastolic closing margin, a metric of cerebral perfusion that normalizes diastolic arterial blood pressure to the critical closing pressure, may be a better measure than arterial blood pressure for defining cerebral perfusion in premature infants. Elevated diastolic closing margin has been associated with intraventricular hemorrhage. This review summarizes the current state of understanding of cerebral hemodynamics in premature infants.


Subject(s)
Arterial Pressure , Blood Pressure , Brain , Cerebrovascular Circulation , Hemodynamics , Hemorrhage , Homeostasis , Humans , Hypotension , Infant , Infant, Low Birth Weight , Infant, Newborn , Infant, Premature , Perfusion , Reperfusion , Systole , Uncertainty
15.
Article in English | WPRIM | ID: wpr-758844

ABSTRACT

Our aim was (1) to determine the within-day and between-day variability of several indices of systolic and diastolic right ventricular (RV) function by using conventional echocardiography and speckle-tracking echocardiography (STE) (Study 1), (2) to quantify these variables in a large healthy canine population (n = 104) with Doppler-derived estimated systolic pulmonary arterial pressure (SPAP) and left ventricular (LV) function, and (3) to establish the corresponding reference intervals (Study 2). For both studies, RV variables included tricuspid annular plane systolic excursion (TAPSE), right fractional area change (RFAC), STE longitudinal systolic strain (StS) of the RV free wall (RVFW) and of the entire RV (i.e., global RV StS), STE longitudinal systolic RVFW strain rate (SRS), and the diastolic early:late strain rate ratio. All but one within- and between-day coefficients of variation (13/14) were < 15%, the lowest being observed for TAPSE (3.6–9.8%), global RV StS (3.8–9.9%), and RVFW StS (3.7–7.3%). SPAP was weakly and negatively correlated with the TAPSE:body weight ratio (r(s) = −0.26, p = 0.01) and RVFW SRS (r(s) = −0.23, p < 0.05). Reference intervals (lower and upper limits with 90% confidence intervals) were provided for all variables. STE provides a non-invasive evaluation of RV function that may be used for clinical investigations in canine cardiology.


Subject(s)
Animals , Arterial Pressure , Cardiology , Diastole , Dogs , Echocardiography , Heart , Myocardium , Prospective Studies , Systole , Ventricular Function, Right
16.
Singapore medical journal ; : 251-256, 2018.
Article in English | WPRIM | ID: wpr-687876

ABSTRACT

<p><b>INTRODUCTION</b>We aimed to evaluate the effectiveness and safety of canagliflozin as compared to sitagliptin in a real-world setting among multiethnic patients with Type 2 diabetes mellitus (T2DM) in Singapore.</p><p><b>METHODS</b>This was a new-user, active-comparator, single-centre retrospective cohort study. Patients aged 18-69 years with T2DM and estimated glomerular filtration rate ≥ 60 mL/min/1.73 m were eligible for inclusion if they were initiated and maintained on a steady daily dose of canagliflozin 300 mg or sitagliptin 100 mg between 1 May and 31 December 2014, and followed up for 24 weeks.</p><p><b>RESULTS</b>In total, 57 patients (canagliflozin 300 mg, n = 22; sitagliptin 100 mg, n = 35) were included. The baseline patient characteristics in the two groups were similar, with overall mean glycated haemoglobin (HbA1c) of 9.4% ± 1.4%. The use of canagliflozin 300 mg was associated with greater reductions in HbA1c (least squares [LS] mean change -1.6% vs. -0.4%; p < 0.001), body weight (LS mean change -3.0 kg vs. 0.2 kg; p < 0.001) and systolic blood pressure (LS mean change: -9.7 mmHg vs. 0.4 mmHg; p < 0.001), as compared with sitagliptin 100 mg. About half of the patients on canagliflozin 300 mg reported mild osmotic diuresis-related side effects that did not lead to drug discontinuation.</p><p><b>CONCLUSION</b>Our findings suggest that canagliflozin was more effective than sitagliptin in reducing HbA1c, body weight and systolic blood pressure in patients with T2DM, although its use was associated with an increased incidence of mild osmotic diuresis-related side effects.</p>


Subject(s)
Adolescent , Adult , Aged , Blood Glucose , Blood Pressure , Body Mass Index , Body Weight , Canagliflozin , Diabetes Mellitus, Type 2 , Drug Therapy , Female , Glomerular Filtration Rate , Hemoglobins , Humans , Hypoglycemic Agents , Least-Squares Analysis , Male , Middle Aged , Osmosis , Retrospective Studies , Singapore , Sitagliptin Phosphate , Systole , Treatment Outcome , Young Adult
17.
Article in English | WPRIM | ID: wpr-713244

ABSTRACT

BACKGROUND: Decreased left atrial (LA) reservoir function is reported to be associated with elevated left ventricular (LV) end diastolic pressure and LV diastolic dysfunction. Echocardiographic parameters that reflect LA reservoir function include LA total emptying fraction [(maximum LA volume - minimum LA volume) / maximum LA volume], peak LA longitudinal strain (PLALS) at systole, and LA stiffness index (E/E´/PLALS). We aimed to investigate the long-term outcomes of LV diastolic function in children with a history of Kawasaki disease (KD) (KDHx group) by assessing LA reservoir function. METHODS: Retrospectively, echocardiograms performed at a mean follow-up period of 5 years after the acute phase of KD in 24 children in the KDHx group were compared to those from 20 normal control subjects. LA total emptying fraction, PLALS, LA stiffness index, LV peak longitudinal systolic strain (ε), and strain rate (SR) were evaluated with conventional echocardiographic parameters. RESULTS: The mean age at long term follow-up echocardiography in children in the KDHx group was 6.8 years. Five children (20.8%) had coronary artery lesions (CALs) in the acute stage of KD. No children showed CALs at a mean follow-up period of 5 years after the acute phase of KD. There were no significant differences in the conventional echocardiographic parameters and in LA total emptying fraction, PLALS, LA stiffness index, LV peak longitudinal systolic ε, and SR, between the children in the KDHx and control group. CONCLUSION: LV diastolic function assessed by LA reservoir function parameters at long-term follow-up in children in the KDHx group appears to be favorable.


Subject(s)
Atrial Function , Blood Pressure , Child , Coronary Vessels , Echocardiography , Follow-Up Studies , Humans , Mucocutaneous Lymph Node Syndrome , Prognosis , Retrospective Studies , Systole
18.
Yonsei Medical Journal ; : 265-272, 2018.
Article in English | WPRIM | ID: wpr-713094

ABSTRACT

PURPOSE: Impaired left ventricular (LV) global longitudinal strain (GLS) and the presence of microalbuminuria indicate early cardiac and renal dysfunction. We aimed to determine the relationships among 24-h ambulatory blood pressure (BP) variables, LV GLS, and urine albumin creatinine ratio (UACR) in hypertensive patients. MATERIALS AND METHODS: A total of 130 hypertensive patients (mean age 53 years; 59 men) underwent 24-h ambulatory BP monitoring, measurements of peripheral and central BPs, and transthoracic echocardiography. Patients with apparent LV systolic dysfunction (LV ejection fraction < 50%) or chronic kidney disease were not included. LV GLS was calculated using two-dimensional speckle tracking, and UACR was analyzed from spot urine samples. RESULTS: In simple correlation analysis, LV GLS showed the most significant correlation with mean daytime diastolic BP (DBP) (r=0.427, p < 0.001) among the various BP variables analyzed. UACR revealed a significant correlation only with night-time mean systolic BP (SBP) (r=0.253, p=0.019). In multiple regression analysis, daytime mean DBP and night-time mean SBP were independent determinants for LV GLS (β=0.35, p=0.028) and log UACR (β=0.49, p=0.007), respectively, after controlling for confounding factors. Daytime mean DBP showed better diagnostic performance for impaired LV GLS than did peripheral or central DBPs, which were not diagnostic. Night-time mean SBP showed satisfactory diagnostic performance for microalbuminuria. CONCLUSION: There are different associations for daytime and night-time BP with early cardiac and renal dysfunction. Ambulatory BP monitoring provides more relevant BP parameters than do peripheral or central BPs regarding early cardiac and renal dysfunction in hypertensive patients.


Subject(s)
Blood Pressure/physiology , Blood Pressure Monitoring, Ambulatory , Echocardiography , Female , Heart/physiopathology , Humans , Hypertension/diagnostic imaging , Kidney/physiopathology , Kidney Function Tests , Male , Middle Aged , Regression Analysis , Systole/physiology , Ventricular Dysfunction, Left/physiopathology , Ventricular Function, Left/physiology
19.
Article in Chinese | WPRIM | ID: wpr-813179

ABSTRACT

To study the blood flow parameters for 2 anatomical segments of posterior cerebral artery (PCA) in normal singleton fetal.
 Methods: The blood flow velocity parameters peak systolic velocity (PSV), end diastolic velocity (EDV), time-average maximum velocity (TAMAXV), velocity time integral (VTI) and resistance parameters systolic peak velocity and end diastolic velocity ratio (S/D), pulsatility index (PI), resistance index (RI) for 2 anatomical segments in PCA were recorded. The first segment of the PCA (PCAS1) was recorded between the origin of PCA and the proximal part of the posterior communicating artery. The second segment of the PCA (PCAS2) was recorded at the distal part of the posterior communicating artery. The blood parameters in both PCAS1 and PCAS2 were analyzed by using Pearson correlation and multiple curves fitting with gestational age (GA). Paired student's t test was performed to compare the difference in blood parameter between PCAS1 and PCAS2.
 Results: The blood flow velocity parameters in both PCAS1 and PCAS2 were increased with the GA (P0.05). Resistance parameters in PCAS1 were higher than those in PCAS2 (P<0.05).
 Conclusion: The blood flow velocity parameters in both PCAS1 and PCAS2 are increased with GA. The resistance parameters in both PCAS1 and PCAS2 do not change with GA. Study on the velocities and resistance in these 3 arterial branches provides a more comprehensive evaluation on the process of brain circulation.


Subject(s)
Blood Flow Velocity , Physiology , Diastole , Physiology , Female , Gestational Age , Hemodynamics , Physiology , Humans , Posterior Cerebral Artery , Physiology , Pregnancy , Systole , Physiology
20.
Arq. bras. cardiol ; 108(4): 323-330, Apr. 2017. tab, graf
Article in English | LILACS | ID: biblio-838725

ABSTRACT

Abstract Background: Resistance and aerobic training are recommended as an adjunctive treatment for hypertension. However, the number of sessions required until the hypotensive effect of the exercise has stabilized has not been clearly established. Objective: To establish the adaptive kinetics of the blood pressure (BP) responses as a function of time and type of training in hypertensive patients. Methods: We recruited 69 patients with a mean age of 63.4 ± 2.1 years, randomized into one group of resistance training (n = 32) and another of aerobic training (n = 32). Anthropometric measurements were obtained, and one repetition maximum (1RM) testing was performed. BP was measured before each training session with a digital BP arm monitor. The 50 training sessions were categorized into quintiles. To compare the effect of BP reduction with both training methods, we used two-way analysis of covariance (ANCOVA) adjusted for the BP values obtained before the interventions. The differences between the moments were established by one-way analysis of variance (ANOVA). Results: The reductions in systolic (SBP) and diastolic BP (DBP) were 6.9 mmHg and 5.3 mmHg, respectively, with resistance training and 16.5 mmHg and 11.6 mmHg, respectively, with aerobic training. The kinetics of the hypotensive response of the SBP showed significant reductions until the 20th session in both groups. Stabilization of the DBP occurred in the 20th session of resistance training and in the 10th session of aerobic training. Conclusion: A total of 20 sessions of resistance or aerobic training are required to achieve the maximum benefits of BP reduction. The methods investigated yielded distinct adaptive kinetic patterns along the 50 sessions.


Resumo Fundamento: Os treinamentos de força e aeróbio são indicados para o tratamento adjuvante da hipertensão. Entretanto, o número de sessões necessárias até estabilização do efeito hipotensor com o exercício ainda não está claramente estabelecido. Objetivo: Estabelecer a cinética adaptativa das respostas tensionais em função do tempo e do tipo de treinamento em hipertensos. Métodos: Foram recrutados 69 hipertensos com idade média de 63,4 ± 2,1 anos, randomizados em um grupo de treinamento de força (n = 32) e outro de treinamento aeróbio (n = 32). Foram realizadas medidas antropométricas e testes de uma repetição máxima (1RM). A pressão arterial (PA) foi medida antes de cada sessão de treinamento com um aparelho de pressão digital de braço. As 50 sessões de treinamento foram categorizadas em quintis. Para comparar o efeito da redução da PA entre os métodos de treinamentos (between), utilizamos análise de covariância (ANCOVA) bifatorial ajustada para os valores de PA pré-intervenção. As diferenças entre os momentos foram estabelecidas por análise de variância (ANOVA) unifatorial. Resultados: As reduções na PA sistólica (PAS) e diastólica (PAD) foram de 6,9 mmHg e 5,3 mmHg, respectivamente, com o treinamento de força e 16,5 mmHg e 11,6 mmHg, respectivamente, com o treinamento aeróbio. A cinética hipotensiva da PAS apresentou reduções significativas até a 20ª sessão em ambos os grupos. Observou-se estabilização da PAD na 20ª sessão com o treinamento de força e na 10ª sessão com o aeróbio. Conclusão: São necessárias 20 sessões de treinamento de força ou aeróbio para alcance dos benefícios máximos de redução da PA. Os métodos investigados proporcionaram padrões cinéticos adaptativos distintos ao longo das 50 sessões.


Subject(s)
Humans , Male , Female , Middle Aged , Aged , Exercise/physiology , Resistance Training , Post-Exercise Hypotension/physiopathology , Hypertension/physiopathology , Systole/physiology , Time Factors , Blood Pressure/physiology , Adaptation, Physiological/physiology , Kinetics , Analysis of Variance , Diastole/physiology
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