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1.
Turk Kardiyol Dern Ars ; 49(4): 275-285, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34106061

RESUMO

OBJECTIVE: The current understanding of heart failure (HF) largely centers round left ventricular (LV) function; however, disorders in serial integration of cardiovascular system may cause a hemodynamic picture similar to left-sided HF. Therefore, focusing only on LV function may be a limited and misleading approach. We hypothesized that cardiovascular system has four major integration points, and disintegration in any of these points may produce the hemodynamic picture of HF. METHODS: We used a computational model in which mechanical properties of each chamber were characterized using time-varying elastance, and vascular beds were modeled by series of capacitances and resistances. The required percent changes in stressed volume (Vstressed) was presented as a measure of congestion susceptibility. RESULTS: As mean systemic pressure is closely correlated with pulmonary capillary wedge pressure (PCWP), arteriovenous disintegration can create a diastolic dysfunction pattern, even without any change in diastolic function. For 10%, 20%, 30%, 40%, and 50% interventricular disintegration, required Vstressed for reaching a PCWP over 20 mmHg was decreased by 42.0%, 31.2%, 22.5%, 15%, and 8.3%, respectively. Systolodiastolic disintegration, namely combined changes in the end-diastolic and systolic pressure-volume curves and ventriculoarterial disintegration significantly decreases the required percent change in Vstressed for generating congestion. CONCLUSION: Four disintegration points can produce the hemodynamic picture of HF, which indicates that combination of even seemingly mild abnormalities is more important than an isolated abnormality in a single function of a single chamber. Our findings suggest that a "cardiovascular disintegration" perspective may provide a different approach for assessing the HF syndrome.


Assuntos
Insuficiência Cardíaca/fisiopatologia , Capacitância Vascular/fisiologia , Resistência Vascular/fisiologia , Disfunção Ventricular Esquerda/fisiopatologia , Pressão Sanguínea/fisiologia , Diástole/fisiologia , Hemodinâmica , Humanos , Pressão Propulsora Pulmonar/fisiologia , Sístole/fisiologia , Função Ventricular Esquerda/fisiologia
2.
Circ Heart Fail ; 14(1): e007308, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33464948

RESUMO

While many of the cardiac limitations to exercise performance are now well-characterized, extracardiac limitations to exercise performance have been less well recognized but are nevertheless important. We propose that abnormalities of cardiac preload reserve represents an under-recognized but common cause of exercise limitations. We further propose that mechanistic links exist between conditions as seemingly disparate as heart failure with preserved ejection fraction, nonalcoholic fatty liver disease, and pelvic venous compression/obstruction syndromes (eg, May-Thurner). We conclude that extracardiac abnormalities of preload reserve serve as a major pathophysiologic mechanism underlying these and other disease states.


Assuntos
Doenças do Sistema Nervoso Autônomo/fisiopatologia , Débito Cardíaco/fisiologia , Tolerância ao Exercício/fisiologia , Insuficiência Cardíaca/fisiopatologia , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Volume Sistólico/fisiologia , Veias/fisiopatologia , Hemodinâmica , Humanos , Hepatopatias/fisiopatologia , Síndrome de May-Thurner , Síndrome da Taquicardia Postural Ortostática/fisiopatologia , Síncope Vasovagal/fisiopatologia , Capacitância Vascular/fisiologia
3.
J Am Heart Assoc ; 10(20): e023043, 2021 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-34612057

RESUMO

Background Although the prognostic importance of pulmonary arterial capacitance (PAC; stroke volume/pulmonary arterial pulse pressure) has been elucidated in heart failure with reduced ejection fraction, whether its significance in patients suffering from heart failure with preserved ejection fraction is not known. We aimed to examine the association of PAC with outcomes in inpatients with heart failure with preserved ejection fraction. Methods and Results We prospectively studied 705 patients (median age, 83 years; 55% women) registered in PURSUIT-HFpEF (Prospective Multicenter Observational Study of Patients With Heart Failure With Preserved Ejection Fraction). We investigated the association of echocardiographic PAC at discharge with the primary end point of all-cause death or heart failure rehospitalization with a mean follow-up of 384 days. We further tested the acceptability of the prognostic significance of PAC in a subgroup of patients (167/705 patients; median age, 81 years; 53% women) in whom PAC was assessed by right heart catheterization. The median echocardiographic PAC was 2.52 mL/mm Hg, with a quartile range of 1.78 to 3.32 mL/mm Hg. Univariable and multivariable Cox regression testing revealed that echocardiographic PAC was associated with the primary end point (unadjusted hazard ratio, 0.82; 95% CI, 0.72-0.92; P=0.001; adjusted hazard ratio, 0.86; 95% CI, 0.74-0.99; P=0.035, respectively). Univariable Cox regression testing revealed that PAC assessed by right heart catheterization (median calculated PAC, 2.82 mL/mm Hg) was also associated with the primary end point (unadjusted HR, 0.70; 95% CI, 0.52-0.91; P=0.005). Conclusions A prospective cohort study revealed that impaired PAC diagnosed with both echocardiography and right heart catheterization was associated with adverse outcomes in inpatients with heart failure with preserved ejection fraction. Registration URL: https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000024414. Unique identifier: UMIN000021831.


Assuntos
Insuficiência Cardíaca , Hipertensão Pulmonar , Artéria Pulmonar , Capacitância Vascular , Idoso de 80 Anos ou mais , Feminino , Insuficiência Cardíaca/fisiopatologia , Humanos , Hipertensão Pulmonar/fisiopatologia , Masculino , Prognóstico , Estudos Prospectivos , Artéria Pulmonar/fisiopatologia , Volume Sistólico , Capacitância Vascular/fisiologia , Função Ventricular Esquerda
4.
J Exp Biol ; 223(Pt 4)2020 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-32079682

RESUMO

In the 1950s, Arthur C. Guyton removed the heart from its pedestal in cardiovascular physiology by arguing that cardiac output is primarily regulated by the peripheral vasculature. This is counterintuitive, as modulating heart rate would appear to be the most obvious means of regulating cardiac output. In this Review, we visit recent and classic advances in comparative physiology in light of this concept. Although most vertebrates increase heart rate when oxygen demands rise (e.g. during activity or warming), experimental evidence suggests that this tachycardia is neither necessary nor sufficient to drive a change in cardiac output (i.e. systemic blood flow, Q̇sys) under most circumstances. Instead, Q̇sys is determined by the interplay between vascular conductance (resistance) and capacitance (which is mainly determined by the venous circulation), with a limited and variable contribution from heart function (myocardial inotropy). This pattern prevails across vertebrates; however, we also highlight the unique adaptations that have evolved in certain vertebrate groups to regulate venous return during diving bradycardia (i.e. inferior caval sphincters in diving mammals and atrial smooth muscle in turtles). Going forward, future investigation of cardiovascular responses to altered metabolic rate should pay equal consideration to the factors influencing venous return and cardiac filling as to the factors dictating cardiac function and heart rate.


Assuntos
Débito Cardíaco/fisiologia , Vertebrados/fisiologia , Animais , Circulação Sanguínea/fisiologia , Mergulho/fisiologia , Frequência Cardíaca/fisiologia , Capacitância Vascular/fisiologia , Resistência Vascular/fisiologia
6.
Circ J ; 83(11): 2222-2228, 2019 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-31484840

RESUMO

BACKGROUND: Pulmonary arterial capacitance (PAC) is a determinant of right ventricular afterload and a strong independent predictor of unfavorable outcomes in advanced heart failure (HF) with pulmonary hypertension (PH). We aimed to test the hypothesis that preoperative PAC may affect postoperative clinical outcomes in patients undergoing aortic valve replacement (AVR) for severe aortic valve stenosis (AS), even in the absence of PH.Methods and Results:We studied 116 patients who underwent AVR for severe AS between January 2005 and December 2017. Right heart catheterization was performed for all patients prior to surgery. PAC and pulmonary vascular resistance (PVR) fit well to a hyperbolic relationship (PAC=0.23/PVR, R2=0.73). PAC also showed an inverse relationship with pulmonary capillary wedge pressure (PCWP) (r=-0.15) and mean pulmonary arterial pressure (r=-0.29) and provided a stronger prediction of death or HF admission than PCWP or PVR (area under the ROC curve of 0.74 vs. 0.40 and 0.41, respectively, P=0.002). During a median follow-up of 36 months, PAC (hazard ratio, 0.48; 95% confidence interval, 0.30-0.78; P=0.003) was an independent predictor of death or hospitalization for HF. CONCLUSIONS: In these patients undergoing AVR for severe AS, even in the absence of PH, preoperative reduced PAC was independently associated with adverse surgical outcomes. It seems that preoperative PAC has potential as an independent predictor of long-term prognosis after AVR for severe AS.


Assuntos
Estenose da Valva Aórtica/cirurgia , Valva Aórtica/cirurgia , Implante de Prótese de Valva Cardíaca , Artéria Pulmonar/fisiopatologia , Capacitância Vascular , Idoso , Idoso de 80 Anos ou mais , Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/complicações , Estenose da Valva Aórtica/diagnóstico , Estenose da Valva Aórtica/fisiopatologia , Feminino , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/fisiopatologia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Humanos , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/fisiopatologia , Masculino , Recuperação de Função Fisiológica , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Disfunção Ventricular Direita/etiologia , Disfunção Ventricular Direita/fisiopatologia , Função Ventricular Direita
7.
Int J Cardiovasc Imaging ; 35(9): 1581-1586, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30968263

RESUMO

A growing body of evidence has demonstrated that pulmonary arterial capacitance (PAC) is the strongest hemodynamic predictor of clinical outcomes across a wide spectrum of cardiovascular disease, including pulmonary hypertension and heart failure. We hypothesized that a ratio of right ventricular stroke volume (RVOT VTI) to the associated peak arterial systolic pressure (PASP) could function as a reliable non-invasive surrogate for PAC. We performed a prospective study of patients undergoing simultaneous transthoracic echocardiography and right heart catheterization (RHC) for various clinical indications. Measurements of the RVOT VTI/PASP ratio from echocardiographic measurements were compared against PAC calculated from RHC measurements. Correlation coefficients and Bland-Altman analysis compared the RVOT VTI/PASP ratio with PAC. Forty-five subjects were enrolled, 38% were female and mean age was 54 years (SD 13 years). The reason for referral to RHC was most commonly post-heart transplant surveillance (40%), followed by heart failure (22%), and pulmonary hypertension (18%). Pre-capillary pulmonary hypertension was present in 18%, isolated post-capillary pulmonary hypertension was present in 13%, and combined pre-and post-capillary pulmonary hypertension was present in 29%. The RVOT VTI/PASP ratio was obtainable in the majority of patients (78%), and Pearson's correlation demonstrated moderately-strong association between PAC and the RVOT VTI/PASP ratio, r = 0.75 (P < 0.001). Bland-Altman analysis demonstrated good agreement between measurements without suggestion of systematic bias and a mean difference in standardized units of - 0.133. In a diverse population of patients and hemodynamic profiles, we validated that the ratio of RVOT VTI/PASP to be a reliably-obtained non-invasive marker associated with PAC.


Assuntos
Pressão Arterial , Ecocardiografia Doppler , Hipertensão Pulmonar/diagnóstico por imagem , Artéria Pulmonar/diagnóstico por imagem , Circulação Pulmonar , Volume Sistólico , Capacitância Vascular , Função Ventricular Direita , Adulto , Idoso , Cateterismo Cardíaco , Feminino , Humanos , Hipertensão Pulmonar/fisiopatologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Artéria Pulmonar/fisiopatologia
8.
Heart Vessels ; 34(3): 470-476, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30225809

RESUMO

Histopathological assessment of the pulmonary arteries is crucial to determine the surgical indications in patients with congenital heart disease (CHD) and intractable pulmonary vascular disease (PVD). We aimed to clarify whether pulmonary hemodynamic parameters can predict PVD in patients with CHD and pulmonary arterial hypertension (PAH) We performed histopathological evaluations of lung specimens and cardiac catheterizations in 27 patients with CHD-PAH. We divided these patients into the patients with and without PVD, and compared pulmonary hemodynamic parameters including pulmonary arterial compliance (Cp) between two groups. Age at lung biopsy was 4 (2-7) months. There were 16 patients with trisomy 21. Cardiac diagnosis included ventricular septal defect in 16, atrial septal defect in 5, atrioventricular septal defect in 4, and others in 2. There were 11 patients with histopathologically proven PVD (Heath-Edwards classification grade ≥ 3 in 5; the index of PVD ≥ 1.1 in 3; extremely thickened media in 6; hypoplasia of the pulmonary arteries in 3). Cp in the patients with PVD was significantly lower than that in patients without PVD (0.99 [0.74-1.42] vs 1.56 [1.45-1.88], p = 0.0047), although there was no significant difference in the ratio of systemic to pulmonary blood flow, pulmonary arterial pressure, and resistance between two groups. A Cp cutoff value of < 1.22 ml/mmHg m2 as a predictor of PVD yielded a sensitivity and a specificity of 93% and 64%, respectively. Pulmonary arterial compliance can be a predictor of PVD among patients with CHD-PAH.


Assuntos
Cardiopatias Congênitas/fisiopatologia , Hipertensão Pulmonar/diagnóstico , Artéria Pulmonar/fisiopatologia , Pressão Propulsora Pulmonar/fisiologia , Capacitância Vascular/fisiologia , Biópsia , Cateterismo Cardíaco , Feminino , Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/diagnóstico , Humanos , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/fisiopatologia , Lactente , Masculino , Prognóstico , Artéria Pulmonar/patologia , Circulação Pulmonar/fisiologia , Estudos Retrospectivos
9.
Menopause ; 25(11): 1180-1186, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30358710

RESUMO

Clinical and experimental evidence suggests that the cardioprotective effect of estrogen replacement is due to effects both on scrum lipids and on blood vessels. Current practice includes the use of a progestin in combination with estrogen if the patient still has her uterus: however, little is known about the effects of combination therapy on vascular reactivity. We therefore studied the effects of estrogen alone and with added progestin on forearm vascular resistance at rest, during reactive hyperemia, and after cold pressor stimulation using plethysmography in six healthy, postmenopausal women. Measurements were made before therapy: after giving conjugated estrogen i.v.; followed by a daily oral dose of 0.625 mg for 21 days; and sequentially after the addition of 10 mg of medroxyprogesterone acetate (MPA) for 10 days. Mean blood pressure did not change significantly. After 21 days of estrogen therapy, forearm blood flow, resting vascular resistance, and resistance after cold pressor stimulation did not change significantly. However, after addition of MPA, resting forearm vascular resistance rose significantly from baseline: 25.7 ±â€Š2.7 U (SE) versus 38.3 ±â€Š2.5 (p = 0.004). In addition, forearm vascular resistance rose to a higher level after cold pressor stimulus during combination therapy (32.3 ±â€Š5.9 vs. 58.4 ±â€Š5.7; p = 0.0057) than after estrogen replacement alone (32.3 ±â€Š5.9 vs. 37.7 ±â€Š5.3; p = NS). We conclude that combination hormone replacement therapy results in higher resting vascular resistance and increased pressor responsiveness than does estrogen replacement therapy alone.


Assuntos
Terapia de Reposição de Estrogênios , Pós-Menopausa/fisiologia , Progestinas/farmacologia , Progestinas/uso terapêutico , Vasoconstrição/efeitos dos fármacos , Administração Intravenosa , Administração Oral , Adulto , Temperatura Baixa , Quimioterapia Combinada , Estrogênios/administração & dosagem , Estrogênios/uso terapêutico , Estrogênios Conjugados (USP)/administração & dosagem , Estrogênios Conjugados (USP)/uso terapêutico , Feminino , Hormônio Foliculoestimulante/sangue , Antebraço/irrigação sanguínea , Humanos , Hiperemia/fisiopatologia , Hormônio Luteinizante/sangue , Acetato de Medroxiprogesterona/administração & dosagem , Acetato de Medroxiprogesterona/uso terapêutico , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional/efeitos dos fármacos , Descanso/fisiologia , Capacitância Vascular/efeitos dos fármacos , Resistência Vascular/efeitos dos fármacos
10.
Am J Physiol Heart Circ Physiol ; 315(3): H669-H680, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29727215

RESUMO

Experimental data indicate that stimulation of the nitric oxide-soluble guanylate cyclase(sGC)-cGMP-PKG pathway can increase left ventricular (LV) capacitance via phosphorylation of the myofilamental protein titin. We aimed to test whether acute pharmacological sGC stimulation with BAY 41-8543 would increase LV capacitance via titin phosphorylation in healthy and deoxycorticosteroneacetate (DOCA)-induced hypertensive pigs. Nine healthy Landrace pigs and 7 pigs with DOCA-induced hypertension and LV concentric hypertrophy were acutely instrumented to measure LV end-diastolic pressure-volume relationships (EDPVRs) at baseline and during intravenous infusion of BAY 41-8543 (1 and 3 µg·kg-1·min-1 for 30 min, respectively). Separately, in seven healthy and six DOCA pigs, transmural LV biopsies were harvested from the beating heart to measure titin phosphorylation during BAY 41-8543 infusion. LV EDPVRs before and during BAY 41-8543 infusion were superimposable in both healthy and DOCA-treated pigs, whereas mean aortic pressure decreased by 20-30 mmHg in both groups. Myocardial titin phosphorylation was unchanged in healthy pigs, but total and site-specific (Pro-Glu-Val-Lys and N2-Bus domains) titin phosphorylation was increased in DOCA-treated pigs. Bicoronary nitroglycerin infusion in healthy pigs ( n = 5) induced a rightward shift of the LV EDPVR, demonstrating the responsiveness of the pathway in this model. Acute systemic sGC stimulation with the sGC stimulator BAY 41-8543 did not recruit an LV preload reserve in both healthy and hypertrophied LV porcine myocardium, although it increased titin phosphorylation in the latter group. Thus, increased titin phosphorylation is not indicative of increased in vivo LV capacitance. NEW & NOTEWORTHY We demonstrate that acute pharmacological stimulation of soluble guanylate cyclase does not increase left ventricular compliance in normal and hypertrophied porcine hearts. Effects of long-term soluble guanylate cyclase stimulation with oral compounds in disease conditions associated with lowered myocardial cGMP levels, i.e., heart failure with preserved ejection fraction, remain to be investigated.


Assuntos
Cardiomegalia/metabolismo , Ventrículos do Coração/metabolismo , Guanilil Ciclase Solúvel/metabolismo , Capacitância Vascular , Animais , Pressão Sanguínea , Cardiomegalia/etiologia , Cardiomegalia/fisiopatologia , Conectina/metabolismo , GMP Cíclico/metabolismo , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Acetato de Desoxicorticosterona/toxicidade , Feminino , Ventrículos do Coração/efeitos dos fármacos , Morfolinas/farmacologia , Nitroglicerina/farmacologia , Pirimidinas/farmacologia , Suínos , Vasodilatadores/farmacologia , Função Ventricular Esquerda
12.
Exp Aging Res ; 44(3): 232-245, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29558315

RESUMO

Brain-derived neurotrophic factor (BDNF) has been linked to cardiovascular health and function, however, the exact role is yet to be understood. The current study examined the relationship of circulatory BDNF with vascular function in Parkinson's disease (PD). ELISA was used to determine plasma BDNF in PD patients and healthy control (CT). Additionally, forearm resting blood flow (RBf), vascular resistance (RVr), venous capacitance (RVc), and venous outflow (RVo) as well as post occlusion blood flow (OcBf), vascular resistance (OcVr), venous capacitance (OcVc), and venous outflow (OcVo) were obtained using strain-gauge plethysmography. Simple linear regression showed that being PD patient can predict (p < 0.05) 12.9% of BDNF, 16.8% of RVc, 15.0% of OcVc, and 13.6% of OcVo. Subsequent stepwise regression included BDNF, RVc, OcVc, and OcVo, showed that being PD patient predicted (p < 0.05) 58.0% of BDNF, 47.7% of OcVo, and 15.1% of OcVc. Another simple linear regression demonstrated that BDNF predicted (p < 0.05) 18.5% of OcBf, 22.0% of OcVr, and 24.1% of OcVc in PD. In a subsequent stepwise linear regression, BDNF explained 26% ofOcVr (p = 0.008) and 42% of OcVc (p = 0.002) in PD. The study showed that BDNF is reduced and related to altered vascular function in PD. The results suggest that BDNF might contribute to preserving and maybe improving vascular function in PD.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/sangue , Doença de Parkinson/sangue , Doença de Parkinson/fisiopatologia , Adulto , Idoso , Envelhecimento , Estudos de Casos e Controles , Estudos Transversais , Feminino , Antebraço/irrigação sanguínea , Humanos , Masculino , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional/fisiologia , Capacitância Vascular/fisiologia , Resistência Vascular/fisiologia
13.
Angiology ; 69(5): 443-448, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29025284

RESUMO

Data are limited on whether valvular calcification is associated with aortic wall stiffness. We tested whether aortic valve calcification (AVC) and/or mitral valve calcification (MVC) is inversely associated with aortic distensibility (AD). Cross-sectional study conducted in a subset of the Multi-Ethnic Study of Atherosclerosis (MESA) included 3676 MESA participants aged 44 to 84 years with AD measured with magnetic resonance imaging and with AVC and MVC measured with noncontrast cardiac computed tomography scans. Both AVC and MVC were divided into 3 categories: zero, < median values (low), and ≥ median values (high) for patients with nonzero values. Overall, 88% (n = 3256) and 92% (n = 3365) of participants had zero AVC and MVC, while 6% (n = 211) and 4% (n = 156) had low, and 6% (n = 209) and 4% (n = 155) had high values of AVC and MVC, respectively. The AVC was independently associated with AD after adjusting for age, gender, and ethnicity ( P = .035). No association was noted between AVC groups and AD after adjustment for all covariates or MVC groups and AD in any model.


Assuntos
Estenose da Valva Aórtica/fisiopatologia , Valva Aórtica/patologia , Aterosclerose/etnologia , Calcinose/fisiopatologia , Etnicidade , Estenose da Valva Mitral/fisiopatologia , Capacitância Vascular/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/etnologia , Aterosclerose/fisiopatologia , Calcinose/diagnóstico por imagem , Calcinose/etnologia , Estudos Transversais , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estenose da Valva Mitral/diagnóstico por imagem , Estenose da Valva Mitral/etnologia , Tomografia Computadorizada por Raios X
14.
Pediatr Dermatol ; 35(1): 87-91, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29143471

RESUMO

BACKGROUND/OBJECTIVES: Ethnic and racial differences in infant skin have not been well characterized. The purpose of this study was to establish whether there are ethnic differences and similarities in the stratum corneum (SC) functions of Thai and Chinese infants. METHODS: Healthy infants 6 to 24 months of age (N = 60; 30 Thai, 30 Chinese) who resided in Bangkok, Thailand, were enrolled. Transepidermal water loss (TEWL) and SC hydration (capacitance) on the thigh, buttock, and upper arm were measured. Ceramide content was determined in the SC on the upper arm. RESULTS: SC hydration was not remarkably different between the two ethnicities at any site measured, but TEWL was significantly higher in Chinese infants than in Thai infants at all sites. Hydration of the SC was not significantly correlated with age in either ethnicity. TEWL had significant but weak correlations with age on the thigh and upper arm in Thai infants. Ceramide content was significantly higher in Chinese SC than in Thai SC. No relationship between ceramide content and TEWL or hydration was observed in either ethnicity. CONCLUSION: The significant differences in TEWL and ceramide contents between Chinese and Thai infant skin could prove useful in designing skin care and diapering products that are best suited for each ethnicity.


Assuntos
Ceramidas/análise , Epiderme/fisiologia , Capacitância Vascular/fisiologia , Perda Insensível de Água/fisiologia , Água Corporal/fisiologia , Etnicidade , Feminino , Humanos , Lactente , Masculino , Tailândia/etnologia
16.
Sci Rep ; 7: 42797, 2017 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-28211486

RESUMO

Whereas Huntington's disease (HD) is unequivocally a neurological disorder, a critical mass of emerging studies highlights the occurrence of peripheral pathology like cardiovascular defects in both animal models and humans. The overt impairment in cardiac function is normally expected to be associated with peripheral vascular dysfunction, however whether this assumption is reasonable or not in HD is still unknown. In this study we functionally characterized the vascular system in R6/2 mouse model (line 160 CAG), which recapitulates several features of human pathology including cardiac disease. Vascular reactivity in different arterial districts was determined by wire myography in symptomatic R6/2 mice and age-matched wild type (WT) littermates. Disease stage was assessed by using well-validated behavioural tests like rotarod and horizontal ladder task. Surprisingly, no signs of vascular dysfunction were detectable in symptomatic mice and no link with motor phenotype was found.


Assuntos
Artérias/fisiologia , Proteína Huntingtina/genética , Doença de Huntington/patologia , Músculo Esquelético/fisiopatologia , Animais , Modelos Animais de Doenças , Eletromiografia , Humanos , Doença de Huntington/genética , Doença de Huntington/fisiopatologia , Camundongos , Camundongos Transgênicos , Mutação , Fenótipo , Capacitância Vascular
17.
J Pediatr ; 180: 75-79.e2, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27810156

RESUMO

OBJECTIVES: To evaluate the clinical utility of pulmonary artery capacitance index (PACi) in the assessment of disease severity and prognostic value in children with idiopathic and heritable pulmonary arterial hypertension (PAH). STUDY DESIGN: PACi is defined as the ratio of stroke volume index over pulmonary pulse pressure. A retrospective study was performed to compare PACi, brain natriuretic peptide (BNP), 6-minute walk distance, New York Heart association (NYHA) functional class, and adverse outcomes (hospitalization due to heart failure, lung transplantation, and cardiac mortality) in 72 Japanese children (10 ± 3.6 years) with idiopathic and heritable PAH. RESULTS: PACi had significant correlations with pulmonary vascular resistance index (r =-0.73, P < .0001), BNP levels (r = -0.40, P = .0008), and 6-minute walk distance (r = 0.57, P < .05). Statistically significant differences in PACi were observed between NYHA functional class II vs combined III and IV (median; 1.1 vs 0.6 mL/mm Hg/m2, respectively, P < .05). There were 25 of 72 (35%) children who had an adverse event including initiation of hospitalization due to heart failure, lung transplantation, and death. Cumulative event-free survival rate was significantly lower when PACi was <0.85 mL/mm Hg/m2 (log-rank test, P < .0001). CONCLUSIONS: PACi correlated with BNP and NYHA functional class and may serve as a strong prognostic marker in children with idiopathic and heritable PAH.


Assuntos
Hipertensão Pulmonar Primária Familiar/fisiopatologia , Artéria Pulmonar/fisiopatologia , Capacitância Vascular , Criança , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Índice de Gravidade de Doença
18.
PLoS One ; 11(11): e0165603, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27875533

RESUMO

BACKGROUND: Although pulmonary hypertension due to left heart disease (LHD-PH) accounts for the largest proportion of pulmonary hypertension, few reports on the epidemiological analysis of LHD-PH exist. Recently, pulmonary arterial capacitance (PAC) has attracted attention as a possible factor of right ventricular afterload along with pulmonary vascular resistance. We therefore investigated the clinical significance of PAC in LHD-PH. METHODS: The subject consisted of 252 LHD-PH patients (145 men, mean age 63.4 ± 14.7 years) diagnosed by right heart catheterization. PAC was estimated by the ratio between stroke volume and pulmonary arterial pulse pressure. Patients were classified into four groups according to the PAC (1st quartile was 0.74 to 1.76 ml/mmHg, the 2nd quartile 1.77 to 2.53 ml/mmHg, the 3rd quartile 2.54 to 3.59 ml/mmHg, and the 4th quartile 3.61 to 12.14 ml/mmHg). The end-points were defined as rehospitalization due to worsening heart failure and/or cardiac death. The Cox proportional hazard regression model was used to determine what variables were associated with cardiac events. RESULTS: The patients in the 1st quartile had the lowest cardiac index and stroke volume index, and the highest mean pulmonary arterial pressure, mean pulmonary capillary wedge pressure, and pulmonary vascular resistance compared with the 2nd, 3rd, and 4th quartiles. Fifty-four patients experienced cardiac events during the follow-up period (median 943 days). The event-free rate of the 1st quartile was significantly lower than that of the 3rd and 4th quartiles (66.7% vs 82.5% [3rd quartile], P = 0.008; and 92.1% [4th quartile], P < 0.001). The Cox hazard analysis revealed that PAC was significantly associated with cardiac events (HR 0.556, 95% CI 0.424-0.730, P < 0.001). CONCLUSION: PAC is useful in the prediction of cardiac event risk in LHD-PH patients.


Assuntos
Síndrome Coronariana Aguda/fisiopatologia , Insuficiência Cardíaca/fisiopatologia , Hipertensão Pulmonar/fisiopatologia , Artéria Pulmonar/fisiopatologia , Volume Sistólico , Capacitância Vascular , Síndrome Coronariana Aguda/etiologia , Idoso , Feminino , Seguimentos , Insuficiência Cardíaca/etiologia , Humanos , Hipertensão Pulmonar/complicações , Masculino , Pessoa de Meia-Idade
19.
Rev. bras. ativ. fís. saúde ; 21(6): 542-550, nov. 2016. tab, fig
Artigo em Português | LILACS | ID: biblio-831683

RESUMO

Objetivou-se testar a hipótese de que a prática regular de exercício físico melhora a função vascular de filhos de hipertensos em repouso. Foram avaliados 13 indivíduos fisicamente ativos filhos de hipertensos (FHA) e 22 indivíduos sedentários filhos de hipertensos (FHS), pareados por idade (22,5±2,9 vs. 23,8±2,7 anos, p=0,18) e IMC (23,8±1,9 vs. 23,0±3,0 kg/m², p=0,45). Foram registrados, simultaneamente, a frequência cardíaca, a pressão arterial, minuto a minuto (método oscilométrico ­ DIXTAL 2022®) e o fluxo sanguíneo do antebraço (pletismografia de oclusão venosa ­ Hokanson®), continuamente, durante 3 minutos em repouso. A função vascular foi avaliada por meio da condutância vascular do antebraço, calculada pela divisão do fluxo sanguíneo do antebraço pela pressão arterial média e multiplicada por 100. Foi adotado significância de p≤0,05. Como resultados, em condições basais, os grupos FHA e FHS foram semelhantes para pressão arterial sistólica (124 ± 9 vs. 121 ± 11 mmHg, p=0,42), diastólica (64 ± 5 vs. 64 ± 5 mmHg, p=0,94), média (84 ± 6 vs. 83 ± 7 mmHg, p=0,71) e fluxo sanguíneo do antebraço (3,6 ± 1,1 vs. 2,9 ± 0,9 ml/min/100ml, p=0,06). Mas, o grupo FHA apresentou menor valor de frequência cardíaca de repouso (61 ± 7 vs. 70 ± 8 bpm, p<0,01) e maior condutância vascular do antebraço (4,3 ± 1,3 vs. 3,4 ± 1,0 unidades, p=0,05). Conclui-se que indivíduos fisicamente ativos filhos de hipertensos apresentam melhor função vascular em situação de repouso.


The aim of this study was to test the hypothesis that regular physical exercise practice improves vascular function at rest of hypertensive parents' offspring. We evaluated 13 physically active offspring of hypertensive (FHA) parents and 22 sedentary offspring of hypertensive (FHS), matched by age (22.5 ± 2.9 vs. 23.8 ± 2.7 years, p=0.18) and BMI (23.8 ± 1.9 vs. 23.0 ± 3.0 kg/m², p=0.45). Heart rate, minute by minute, blood pressure (oscillometric method - DIXTAL 2022®), and forearm blood flow (venous occlusion plethysmography - Hokanson®) were continuously recorded for 3 minutes at rest. Vascular function was assessed by forearm vascular conductance, which was calculated by the division of forearm blood flow by mean arterial pressure, multiplied by 100. A p-value <0.05 was considered statistically significant. At rest condition, the groups were similar for systolic (124 ± 9 vs. 121 ± 11 mmHg, p=0.42), diastolic (64 ± 5 vs. 64 ± 5 mmHg, p=0.94), mean blood pressure (84 ± 6 vs. 83 ± 7 mmHg, p=0.71) and forearm blood flow (3.6 ± 1.1 vs. 2.9 ± 0.9 ml/min/100ml, p=0.06). On the other hand, FHA group showed lower resting heart rate (61 ± 7 vs. 70 ± 8 bpm, p<0,01) and higher forearm vascular conductance (4.3 ± 1.3 vs. 3.4 ± 10 units, p=0.05) than FHS group. We concluded that physically active offspring of hypertensive parents presents improved vascular function at rest in comparison with sedentary ones.


Assuntos
Humanos , Masculino , Feminino , Adulto , Hereditariedade , Hipertensão , Capacitância Vascular
20.
J Coll Physicians Surg Pak ; 26(9): 736-9, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27671175

RESUMO

OBJECTIVE: To compare mean per-operative flow capacity between skeletonized and pedicled left internal mammary artery (LIMA) in patients undergoing coronary artery bypass grafting (CABG) surgery. STUDY DESIGN: Randomized control trial. PLACE AND DURATION OF STUDY: Department of Cardiac Surgery, Armed Forces Institute of Cardiology and National Institute of Heart Diseases (AFIC-NIHD), Rawalpindi, Pakistan from February to August, 2013. METHODOLOGY: Patients undergoing CABG for coronary artery disease, under 80 years, excluded by the exclusion criteria; and fulfilling the inclusion criteria were randomly assigned to two groups of 70 each. One group underwent skeletonized and the other underwent pedicled technique of LIMAharvesting. Free flow was checked just before anastamosis of each LIMAto the LAD, manually in blood flow in ml per minute during cardiopulmonary bypass by allowing it to bleed into a 100 ml container over 20 seconds. Aspecialized proforma was used to record the age, gender, weight, disease, type of IMA used, and free flow of the IMA. Data was analyzed using SPSS 18. RESULTS: The mean age of the patients was 57.16 years in 40 patients, ranging from 36 to 75 years. Disease pattern analysis showed 5%, 10.7% and 84.3% single, double and triple vessel coronary artery disease, respectively. There was significantly higher free flow in the skeletonized group than the pedicled group (p=0.04). CONCLUSION: Skeletonized IMAhad superior flow to pedicled IMAin addition to its traditional proven advantages, which justifies its further use as a conduit for myocardial revascularization.


Assuntos
Ponte de Artéria Coronária/métodos , Doença da Artéria Coronariana/cirurgia , Anastomose de Artéria Torácica Interna-Coronária/métodos , Artéria Torácica Interna/cirurgia , Fluxo Sanguíneo Regional/fisiologia , Coleta de Tecidos e Órgãos/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Ponte Cardiopulmonar , Estudos de Coortes , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/fisiopatologia , Feminino , Humanos , Masculino , Artéria Torácica Interna/fisiopatologia , Pessoa de Meia-Idade , Paquistão , Compostos Radiofarmacêuticos , Resultado do Tratamento , Capacitância Vascular/fisiologia , Grau de Desobstrução Vascular/fisiologia
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