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1.
Cochrane Database Syst Rev ; 12: CD004349, 2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33332584

RESUMO

BACKGROUND: This is the first update of this review first published in 2009. When treating elevated blood pressure, doctors usually try to achieve a blood pressure target. That target is the blood pressure value below which the optimal clinical benefit is supposedly obtained. "The lower the better" approach that guided the treatment of elevated blood pressure for many years was challenged during the last decade due to lack of evidence from randomised trials supporting that strategy. For that reason, the standard blood pressure target in clinical practice during the last years has been less than 140/90 mm Hg for the general population of patients with elevated blood pressure. However, new trials published in recent years have reintroduced the idea of trying to achieve lower blood pressure targets. Therefore, it is important to know whether the benefits outweigh harms when attempting to achieve targets lower than the standard target. OBJECTIVES: The primary objective was to determine if lower blood pressure targets (any target less than or equal to 135/85 mm Hg) are associated with reduction in mortality and morbidity as compared with standard blood pressure targets (less than or equal to 140/ 90 mm Hg) for the treatment of patients with chronic arterial hypertension. The secondary objectives were: to determine if there is a change in mean achieved systolic blood pressure (SBP) and diastolic blood pressure (DBP associated with "lower targets" as compared with "standard targets" in patients with chronic arterial hypertension; and to determine if there is a change in withdrawals due to adverse events with "lower targets" as compared with "standard targets", in patients with elevated blood pressure. SEARCH METHODS: The Cochrane Hypertension Information Specialist searched the following databases for randomised controlled trials up to May 2019: the Cochrane Hypertension Specialised Register, CENTRAL (2019, Issue 4), Ovid MEDLINE, Ovid Embase, the WHO International Clinical Trials Registry Platform, and ClinicalTrials.gov. We also contacted authors of relevant papers regarding further published and unpublished work. The searches had no language restrictions. SELECTION CRITERIA: Randomised controlled trials (RCTs) comparing patients allocated to lower or to standard blood pressure targets (see above). DATA COLLECTION AND ANALYSIS: Two review authors (JAA, VL) independently assessed the included trials and extracted data. Primary outcomes were total mortality; total serious adverse events; myocardial infarction, stroke, congestive heart failure, end stage renal disease, and other serious adverse events. Secondary outcomes were achieved mean SBP and DBP, withdrawals due to adverse effects, and mean number of antihypertensive drugs used. We assessed the risk of bias of each trial using the Cochrane risk of bias tool and the certainty of the evidence using the GRADE approach.  MAIN RESULTS: This update includes 11 RCTs involving 38,688 participants with a mean follow-up of 3.7 years. This represents 7 new RCTs compared with the original version. At baseline the mean weighted age was 63.1 years and the mean weighted blood pressure was 155/91 mm Hg. Lower targets do not reduce total mortality (risk ratio (RR) 0.95, 95% confidence interval (CI) 0.86 to 1.05; 11 trials, 38,688 participants; high-certainty evidence) and do not reduce total serious adverse events (RR 1.04, 95% CI 0.99 to 1.08; 6 trials, 18,165 participants; moderate-certainty evidence). This means that the benefits of lower targets do not outweigh the harms as compared to standard blood pressure targets. Lower targets may reduce myocardial infarction (RR 0.84, 95% CI 0.73 to 0.96; 6 trials, 18,938 participants, absolute risk reduction (ARR) 0.4%, number needed to treat to benefit (NNTB) 250 over 3.7 years) and congestive heart failure (RR 0.75, 95% CI 0.60 to 0.92; 5 trials, 15,859 participants, ARR 0.6%, NNTB  167 over 3.7 years) (low-certainty for both outcomes). Reduction in myocardial infarction and congestive heart failure was not reflected in total serious adverse events. This may be due to an increase in other serious adverse events (RR 1.44, 95% CI 1.32 to 1.59; 6 trials. 18,938 participants, absolute risk increase (ARI) 3%,  number needed to treat to harm (NNTH) 33 over four years) (low-certainty evidence). Participants assigned to a "lower" target received one additional antihypertensive medication and achieved a significantly lower mean SBP (122.8 mm Hg versus 135.0 mm Hg, and a lower mean DBP (82.0 mm Hg versus 85.2 mm Hg, than those assigned to "standard target". AUTHORS' CONCLUSIONS: For the general population of persons with elevated blood pressure, the benefits of trying to achieve a lower blood pressure target rather than a standard target (≤ 140/90 mm Hg) do not outweigh the harms associated with that intervention. Further research is needed to see if some groups of patients would benefit or be harmed by lower targets. The results of this review are primarily applicable to older people with moderate to high cardiovascular risk. They may not be applicable to other populations.


Assuntos
Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/fisiologia , Hipertensão/tratamento farmacológico , Viés , Doenças Cardiovasculares/mortalidade , Causas de Morte , Intervalos de Confiança , Diástole/fisiologia , Guias como Assunto , Insuficiência Cardíaca/prevenção & controle , Humanos , Hipertensão/mortalidade , Falência Renal Crônica/mortalidade , Pessoa de Meia-Idade , Infarto do Miocárdio/prevenção & controle , Números Necessários para Tratar , Ensaios Clínicos Controlados Aleatórios como Assunto , Valores de Referência , Acidente Vascular Cerebral/epidemiologia
2.
PLoS One ; 15(10): e0239684, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33031416

RESUMO

BACKGROUND: Recently, myocardial work analysis as an echocardiographic tool to non-invasively determine LV work has been introduced and validated against invasive measurements. Based on systolic blood pressure and speckle-tracking derived longitudinal strain (GLS) during systole and isovolumic relaxation, it is considered less load-dependent than LV ejection fraction (LVEF) or GLS and to integrate information on LV active systolic and diastolic work. OBJECTIVES: We aimed to establish reference values for global constructive (GCW) and global wasted work (GWW) as well as of global work index (GWI) and global work efficiency (GWE) across a wide age range and to assess the association with standard echocardiography parameters to estimate the potential additional information provided by myocardial work (MyW). METHODS: The Characteristics and Course of Heart Failure STAges A/B and Determinants of Progression (STAAB) cohort study carefully characterized a representative sample of the population of the City of Würzburg, Germany, aged 30-79 years. We performed myocardial work analysis using the standardized, quality-controlled transthoracic echocardiograms of all individuals lacking any cardiovascular risk factor. RESULTS: Out of 4965 participants, 779 (49±10 years, 59% women) were eligible for the present analysis. Levels of GCW, GWW, and GWE were independent of sex and body mass index, and were stable until the age of 45 years. Thereafter, we observed an upward shift to further stable values of GCW and a linear increase of GWW with advancing age, resulting in lower GWE. Age-adjusted percentiles for GCW, GWW, GWI, and GWE were derived. Higher levels of blood pressure or LV mass were associated with higher GCW, GWI, and GWW, resulting in lower GWE; higher LVEF correlated with higher GCW and GWI, but lower GWW. Higher E/e´ correlated with higher GWW, higher e´ with lower GWW. CONCLUSIONS: Derived from a large sample of apparently healthy individuals from a population based-cohort, we provide age-adjusted reference values for myocardial work indices, applicable for either sex. Weak correlations with common echocardiographic parameters suggest MyW indices to potentially provide additional information, which has to be evaluated in diseased patient cohorts.


Assuntos
Determinação da Pressão Arterial/métodos , Ecocardiografia/métodos , Miocárdio/metabolismo , Adulto , Idoso , Pressão Sanguínea/fisiologia , Estudos de Coortes , Diástole/fisiologia , Feminino , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Contração Miocárdica/fisiologia , Valores de Referência , Volume Sistólico/fisiologia , Sístole/fisiologia , Função Ventricular Esquerda/fisiologia
3.
PLoS One ; 15(7): e0236490, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32716921

RESUMO

Individuals with spinal cord injury develop cardiovascular disease more than age-matched, non-injured cohorts. However, progression of systolic and diastolic dysfunction into cardiovascular disease after spinal cord injury is not well described. We sought to investigate the relationship between systolic and diastolic function in chronic spinal cord injury to describe how biological sex, level, severity, and duration of injury correlate with structural changes in the left ventricle. Individuals with chronic spinal cord injury participated in this study (n = 70). Registered diagnostic cardiac sonographers used cardiac ultrasound to measure dimensions, mass, and systolic and diastolic function of the left ventricle. We found no significant relationship to severity or duration of injury with left ventricle measurements, systolic function outcome, or diastolic function outcome. Moreover, nearly all outcomes measured were within the American Society of Echocardiography-defined healthy range. Similar to non-injured individuals, when indexed by body surface area (BSA) left ventricle mass [-14 (5) g/m2, p < .01], end diastolic volume [-6 (3) mL/m2, p < .05], and end systolic volume [-4 (1) mL/m2, p < .01] were significantly decreased in women compared with men. Likewise, diastolic function outcomes significantly worsened with age: E-wave velocity [-5 (2), p < .01], E/A ratio [-0.23 (0.08), p < .01], and e' velocity [lateral: -1.5 (0.3) cm/s, p < .001; septal: -0.9 (0.2), p < .001] decreased with age while A-wave velocity [5 (1) cm/s, p < .001] and isovolumic relaxation time [6 (3) ms, p < .05] increased with age. Women demonstrated significantly decreased cardiac size and volumes compared with men, but there was no biological relationship to dysfunction. Moreover, individuals were within the range of ASE-defined healthy values with no evidence of systolic or diastolic function and no meaningful relationship to level, severity, or duration of injury. Decreases to left ventricular dimensions and mass seen in spinal cord injury may result from adaptation rather than maladaptive myocardial remodeling, and increased incidence of cardiovascular disease may be related to modifiable risk factors.


Assuntos
Diástole/fisiologia , Traumatismos da Medula Espinal/fisiopatologia , Sístole/fisiologia , Adulto , Pressão Sanguínea , Feminino , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Análise Multivariada , Tamanho do Órgão
4.
PLoS One ; 15(7): e0236680, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32722688

RESUMO

Cachexia is a common multifactorial syndrome in the advanced stages of cancer and accounts for approximately 20-30% of all cancer-related fatalities. In addition to the progressive loss of skeletal muscle mass, cancer results in impairments in cardiac function. We recently demonstrated that WFA attenuates the cachectic skeletal muscle phenotype induced by ovarian cancer. The purpose of this study was to investigate whether ovarian cancer induces cardiac cachexia, the possible pathway involved, and whether WFA attenuates cardiac cachexia. Xenografting of ovarian cancer induced cardiac cachexia, leading to the loss of normal heart functions. Treatment with WFA rescued the heart weight. Further, ovarian cancer induced systolic dysfunction and diastolic dysfunction Treatment with WFA preserved systolic function in tumor-bearing mice, but diastolic dysfunction was partially improved. In addition, WFA abrogated the ovarian cancer-induced reduction in cardiomyocyte cross-sectional area. Finally, treatment with WFA ameliorated fibrotic deposition in the hearts of tumor-bearing animals. We observed a tumor-induced MHC isoform switching from the adult MHCα to the embryonic MHCß isoform, which was prevented by WFA treatment. Circulating Ang II level was increased significantly in the tumor-bearing, which was lowered by WFA treatment. Our results clearly demonstrated the induction of cardiac cachexia in response to ovarian tumors in female NSG mice. Further, we observed induction of proinflammatory markers through the AT1R pathway, which was ameliorated by WFA, in addition to amelioration of the cachectic phenotype, suggesting WFA as a potential therapeutic agent for cardiac cachexia in oncological paradigms.


Assuntos
Caquexia/tratamento farmacológico , Caquexia/etiologia , Coração/efeitos dos fármacos , Miocárdio/patologia , Neoplasias Ovarianas/complicações , Vitanolídeos/farmacologia , Animais , Caquexia/patologia , Caquexia/fisiopatologia , Linhagem Celular Tumoral , Transformação Celular Neoplásica , Diástole/efeitos dos fármacos , Diástole/fisiologia , Feminino , Coração/fisiopatologia , Camundongos , Fenótipo , Sístole/efeitos dos fármacos , Sístole/fisiologia , Vitanolídeos/uso terapêutico
5.
Proc Natl Acad Sci U S A ; 117(31): 18822-18831, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32690703

RESUMO

Muscle contraction is regulated by the movement of end-to-end-linked troponin-tropomyosin complexes over the thin filament surface, which uncovers or blocks myosin binding sites along F-actin. The N-terminal half of troponin T (TnT), TNT1, independently promotes tropomyosin-based, steric inhibition of acto-myosin associations, in vitro. Recent structural models additionally suggest TNT1 may restrain the uniform, regulatory translocation of tropomyosin. Therefore, TnT potentially contributes to striated muscle relaxation; however, the in vivo functional relevance and molecular basis of this noncanonical role remain unclear. Impaired relaxation is a hallmark of hypertrophic and restrictive cardiomyopathies (HCM and RCM). Investigating the effects of cardiomyopathy-causing mutations could help clarify TNT1's enigmatic inhibitory property. We tested the hypothesis that coupling of TNT1 with tropomyosin's end-to-end overlap region helps anchor tropomyosin to an inhibitory position on F-actin, where it deters myosin binding at rest, and that, correspondingly, cross-bridge cycling is defectively suppressed under diastolic/low Ca2+ conditions in the presence of HCM/RCM lesions. The impact of TNT1 mutations on Drosophila cardiac performance, rat myofibrillar and cardiomyocyte properties, and human TNT1's propensity to inhibit myosin-driven, F-actin-tropomyosin motility were evaluated. Our data collectively demonstrate that removing conserved, charged residues in TNT1's tropomyosin-binding domain impairs TnT's contribution to inhibitory tropomyosin positioning and relaxation. Thus, TNT1 may modulate acto-myosin activity by optimizing F-actin-tropomyosin interfacial contacts and by binding to actin, which restrict tropomyosin's movement to activating configurations. HCM/RCM mutations, therefore, highlight TNT1's essential role in contractile regulation by diminishing its tropomyosin-anchoring effects, potentially serving as the initial trigger of pathology in our animal models and humans.


Assuntos
Cardiomiopatias/metabolismo , Mutação/genética , Tropomiosina , Troponina T , Actinas/química , Actinas/metabolismo , Animais , Cálcio/metabolismo , Diástole/genética , Diástole/fisiologia , Proteínas de Drosophila , Humanos , Miócitos Cardíacos/química , Miócitos Cardíacos/metabolismo , Ligação Proteica , Ratos , Tropomiosina/química , Tropomiosina/metabolismo , Troponina T/química , Troponina T/genética , Troponina T/metabolismo
6.
Medicine (Baltimore) ; 99(27): e21062, 2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32629734

RESUMO

BACKGROUND: The benefits of high-intensity interval training (HIIT) are well-known, there is insufficient evidence about the effects of HIIT on heart failure with preserved ejection fraction (HFpEF). METHOD: Multiple databases include MEDLINE, PubMed, EMBASE, CINAHL, Web of Science, PEDro, Cochrane Library, and Google Scholar are used to search for randomized controlled trials investigating the effects of HIIT on HFpEF. All related articles published with the English language with no time limitation will be included. Two reviews independently conducted the selection, data extraction, and quality assessment. The primary outcome is exercise capacity. The secondary outcomes include quality of life (QoL), blood pressure (BP), ventricular function, and left ventricular diastolic function, symptom improvement, endothelial function, and arterial stiffness. Data analysis is performed with Review Manager Software (Version 5.3). RESULT: This systematic review and meta-analysis aim to evaluate the efficacy of HIIT on HFpEF, its outcome will provide reliable evidence for future studies. CONCLUSION: The findings of this study will be published in a related peer-reviewed journal. REGISTRATION NUMBER: INPLASY202050097.


Assuntos
Insuficiência Cardíaca/reabilitação , Treinamento Intervalado de Alta Intensidade/métodos , Volume Sistólico/fisiologia , Pressão Sanguínea/fisiologia , Diástole/fisiologia , Endotélio Vascular/fisiologia , Estudos de Avaliação como Assunto , Tolerância ao Exercício/fisiologia , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/psicologia , Humanos , Qualidade de Vida/psicologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Rigidez Vascular/fisiologia , Função Ventricular Esquerda/fisiologia
7.
J Vis Exp ; (160)2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32597858

RESUMO

Assessment of cardiac function is essential to conduct cardiovascular and pulmonary-vascular preclinical research. Pressure-volume loops (PV loops) generated by recording both pressure and volume during cardiac catheterization are vital when assessing both systolic and diastolic cardiac function. Left and right heart function are closely related, reflected in ventricular interdependence. Thus, recording biventricular function in the same animal is important to get a complete assessment of cardiac function. In this protocol, a closed chest approach to cardiac catheterization consistent with the way catheterization is performed in patients is adopted in mice. While challenging, the closed chest strategy is a more physiological approach, because opening the chest results in major changes in preload and afterload that create artifacts, most notably a fall in systemic blood pressure. While high-resolution echocardiography is used to assess rodents, cardiac catheterization is invaluable, particularly when assessing diastolic pressures in both ventricles. Described here is a procedure to perform invasive, closed chest, sequential left and right ventricular pressure-volume (PV) loops in the same animal. PV loops are acquired using admittance technology with a mouse pressure-volume catheter and pressure-volume system acquisition. The procedure is described, beginning with the neck dissection, which is required to access the right jugular vein and the right carotid artery, to the insertion and positioning of the catheter, and finally the data acquisition. Then, the criteria required to ensure the acquisition of high-quality PV loops are discussed. Finally, the analysis of the left and right ventricular PV loops and the different hemodynamic parameters available to quantify systolic and diastolic ventricular function are briefly described.


Assuntos
Cateterismo Cardíaco , Ventrículos do Coração/fisiopatologia , Pressão , Anestesia , Animais , Pressão Sanguínea/fisiologia , Temperatura Corporal , Cateteres , Análise de Dados , Diástole/fisiologia , Hemodinâmica , Camundongos Endogâmicos C57BL , Sístole/fisiologia
8.
PLoS One ; 15(5): e0232399, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32374790

RESUMO

Heart failure with a preserved ejection fraction (HFpEF) is associated with multiple comorbidities, such as old age, hypertension, type 2 diabetes and obesity and is more prevalent in females. Although the male obese ZSF1 rat has been proposed as a suitable model to study the development of diastolic dysfunction and early HFpEF, studies in female animals have not been performed yet. Therefore, we aimed to characterize the cardiac phenotype in female obese ZSF1 rats and their lean counterparts. Additionally, we aimed to investigate whether differences exist in disease progression in obese male and female ZSF1 rats. Therefore, male and female ZSF1 rats, lean as well as obese (N = 6-9/subgroup), were used. Every two weeks, from 12 to 26 weeks of age, systolic blood pressure and echocardiographic measurements were performed, and venous blood was sampled. Female obese ZSF1 rats, as compared to female lean ZSF1 rats, developed diastolic dysfunction with cardiac hypertrophy and fibrosis in the presence of severe dyslipidemia, increased plasma growth differentiation factor 15 and mild hypertension, and preservation of systolic function. Although obese female ZSF1 rats did not develop hyperglycemia, their diastolic dysfunction was as severe as in the obese males. Taken together, the results from the present study suggest that the female obese ZSF1 rat is a relevant animal model for HFpEF with multiple comorbidities, suitable for investigating novel therapeutic interventions.


Assuntos
Insuficiência Cardíaca/etiologia , Obesidade/complicações , Animais , Pressão Sanguínea/fisiologia , Colágeno/metabolismo , Diástole/fisiologia , Modelos Animais de Doenças , Ecocardiografia , Feminino , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Masculino , Síndrome Metabólica/complicações , Miocárdio/metabolismo , Miocárdio/patologia , Ratos , Ratos Endogâmicos SHR , Ratos Zucker , Caracteres Sexuais , Volume Sistólico/fisiologia , Magreza/fisiopatologia , Remodelação Ventricular/fisiologia
9.
Int Heart J ; 61(2): 301-307, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32224602

RESUMO

Pulmonary hypertension (PH) caused by left-sided heart disease (LHD-PH) is classified into 2 types: isolated post-capillary PH (Ipc-PH) and combined pre- and post-capillary PH (Cpc-PH). However, the impact of pulmonary vascular resistance (PVR) or diastolic pressure gradient (DPG) on the prognosis of LHD-PH has varied among previous studies. Thus, we verified the significance of PVR or DPG on the prognosis of LHD-PH in our series.We analyzed 243 consecutive LHD-PH patients. The patients were divided into 3 groups: Group A, patients with PVR ≤ 3 Wood unit (WU) and DPG < 7 mmHg; Group B, patients with either PVR > 3 WU or DPG ≥ 7 mmHg; and Group C, patients with PVR > 3 WU and DPG ≥ 7 mmHg.The Kaplan-Meier curve demonstrated that Group B had lower cardiac death-free survival compared with Group A, whereas no significant differences were observed when compared with Group C. In the Cox hazard model, DPG was not associated with cardiac death in the LHD-PH patients. However, only in the ischemic heart disease group, patients with DPG ≥ 7 mmHg had worse prognosis compared with those with normal DPG.The cardiac death-free rate of patients with either increased PVR or DPG was close to that of patients with both increased PVR and DPG. It seems reasonable to define Cpc-PH only by PVR in the new criteria. However, the significance of DPG in LHD-PH might be dependent on the underlying cause of LHD-PH.


Assuntos
Pressão Sanguínea/fisiologia , Diástole/fisiologia , Insuficiência Cardíaca/fisiopatologia , Hipertensão Pulmonar/fisiopatologia , Taxa de Sobrevida , Resistência Vascular/fisiologia , Adulto , Idoso , Cardiomiopatias/complicações , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/fisiopatologia , Morte , Feminino , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/diagnóstico por imagem , Doenças das Valvas Cardíacas/complicações , Doenças das Valvas Cardíacas/diagnóstico por imagem , Doenças das Valvas Cardíacas/fisiopatologia , Humanos , Hipertensão Pulmonar/diagnóstico por imagem , Hipertensão Pulmonar/etiologia , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/complicações , Isquemia Miocárdica/diagnóstico por imagem , Isquemia Miocárdica/fisiopatologia , Prognóstico , Modelos de Riscos Proporcionais
10.
PLoS One ; 15(3): e0229636, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32119694

RESUMO

BACKGROUND: Aortic stenosis (AS) may lead to diastolic dysfunction and later on heart failure (HF) with preserved left ventricular ejection fraction (HFpEF) via increased afterload and left-ventricular (LV) hypertrophy. Since epicardial adipose tissue (EAT) is a metabolically active fat depot that is adjacent to the myocardium and can influence cardiomyocytes and LV function via secretion of proinflammatory cytokines, we hypothesized that high amounts of EAT, as assessed by computed tomography (CT), may aggravate the development and severity of LV hypertrophy and diastolic dysfunction in the context of AS. METHODS: We studied 50 patients (mean age 71 ± 9 years; 9 women) in this preliminary study with mild or moderate AS and mild to severe LV diastolic dysfunction (LVDD), diagnosed by echocardiography, who underwent non-contrast cardiac CT and echocardiography. EAT parameters were measured on 2nd generation dual source CT. Conventional two-dimensional echocardiography and Tissue Doppler Imaging (TDI) was performed to assess LV function and to derive myocardial straining parameter. All patients had a preserved LV ejection fraction > 50%. Data was analysed using Pearson's correlation. RESULTS: Only weak correlation was found between EAT volume or density and E/é ratio as LVDD marker (r = -.113 p = .433 and r = .260, p = .068 respectively). Also, EAT volume or density were independent from Global Strain Parameters (r = 0.058 p = .688 and r = -0.207 p = .239). E/é ratio was strongly associated with LVDD (r = .761 p≤0.0001) and Strain Parameters were moderately associated with LV Ejection Fraction (r = -.669 p≤0.001 and r = -.454 P≤0.005). CONCLUSIONS: In this preliminary study in patients with AS, the EAT volume and density as assessed by CT correlated only weakly with LVDD, as expressed by the commonly used E/é ratio, and with LV strain function. Hence, measuring EAT volume and density may neither contribute to the prediction nor upon the severity of LVDD, respectively.


Assuntos
Tecido Adiposo/patologia , Estenose da Valva Aórtica/fisiopatologia , Disfunção Ventricular Esquerda/fisiopatologia , Adiposidade/fisiologia , Idoso , Idoso de 80 Anos ou mais , Diástole/fisiologia , Ecocardiografia/métodos , Feminino , Insuficiência Cardíaca/fisiopatologia , Humanos , Hipertrofia Ventricular Esquerda/fisiopatologia , Masculino , Pessoa de Meia-Idade , Pericárdio/metabolismo , Pericárdio/fisiologia , Volume Sistólico/fisiologia , Tomografia Computadorizada por Raios X/métodos , Função Ventricular Esquerda/fisiologia
11.
Am J Physiol Regul Integr Comp Physiol ; 318(4): R743-R750, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32022579

RESUMO

Chronic changes in left ventricular (LV) hemodynamics, such as those induced by increased afterload (i.e., hypertension), mediate changes in LV function. This study examined the proof of concept that 1) the LV longitudinal strain (ε)-volume loop is sensitive to detecting an acute increase in afterload, and 2) these effects differ between healthy young versus older men. Thirty-five healthy male volunteers were recruited, including 19 young (24 ± 2 yr) and 16 older participants (67 ± 5 yr). Tests were performed before, during, and after 10-min recovery from acute manipulation of afterload. Real-time hemodynamic data were obtained and LV longitudinal ε-volume loops were calculated from four-chamber images using two-dimensional echocardiography. Inflation of the anti-gravity (anti-G) suit resulted in an immediate increase in heart rate, blood pressure, and systemic vascular resistance and a decrease in stroke volume (all P < 0.05). This was accompanied by a decrease in LV peak ε, slower slope of the ε-volume relationship during early diastole, and an increase in uncoupling (i.e., compared with systole; little change in ε per volume decline during early diastole and large changes in ε per volume decline during late diastole) (all P < 0.05). All values returned to baseline levels after recovery (all P > 0.05). Manipulation of cardiac hemodynamics caused comparable effects in young versus older men (all P > 0.05). Acute increases in afterload immediately change the diastolic phase of the LV longitudinal ε-volume loop in young and older men. This supports the potency of the LV longitudinal ε-volume loop to provide novel insights into dynamic cardiac function in humans in vivo.


Assuntos
Envelhecimento , Hemodinâmica , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia , Função Ventricular , Adulto , Idoso , Pressão Sanguínea , Diástole/fisiologia , Ecocardiografia , Ventrículos do Coração , Humanos , Masculino , Pessoa de Meia-Idade , Sístole/fisiologia , Adulto Jovem
12.
J Vis Exp ; (156)2020 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-32090990

RESUMO

Zebrafish are increasingly utilized as a model organism for cardiomyopathies and regeneration. Current methods evaluating cardiac function fail to reliably detect segmental mechanics and are not readily feasible in zebrafish. Here we present a semiautomated, open-source method for the quantitative assessment of four-dimensional (4D) segmental cardiac function: displacement analysis of myocardial mechanical deformation (DIAMOND). Transgenic embryonic zebrafish were imaged in vivo using a light-sheet fluorescence microscopy system with 4D cardiac motion synchronization. Acquired 3D digital hearts were reconstructed at end-systole and end-diastole, and the ventricle was manually segmented into binary datasets. Then, the heart was reoriented and isotropically resampled along the true short axis, and the ventricle was evenly divided into eight portions (I-VIII) along the short axis. Due to the different resampling planes and matrices at end-systole and end-diastole, a transformation matrix was applied for image registration to restore the original spatial relationship between the resampled systolic and diastolic image matrices. After image registration, the displacement vector of each segment from end-systole to end-diastole was calculated based on the displacement of mass centroids in three dimensions (3D). DIAMOND shows that basal myocardial segments adjacent to the atrioventricular canal undergo the highest mechanical deformation and are the most susceptible to doxorubicin-induced cardiac injury. Overall, DIAMOND provides novel insights into segmental cardiac mechanics in zebrafish embryos beyond traditional ejection fraction (EF) under both physiological and pathological conditions.


Assuntos
Algoritmos , Embrião não Mamífero/fisiologia , Coração/embriologia , Coração/fisiologia , Processamento de Imagem Assistida por Computador , Peixe-Zebra/embriologia , Animais , Animais Geneticamente Modificados , Diástole/efeitos dos fármacos , Diástole/fisiologia , Doxorrubicina/farmacologia , Embrião não Mamífero/efeitos dos fármacos , Coração/efeitos dos fármacos , Testes de Função Cardíaca , Ventrículos do Coração/efeitos dos fármacos , Imageamento Tridimensional , Receptores Notch/metabolismo , Sístole/fisiologia
13.
J Pediatr ; 220: 21-26.e1, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32093926

RESUMO

OBJECTIVE: To explore the effect of early-onset preeclampsia on the blood pressure of offspring during the first month of life. STUDY DESIGN: This prospective case-control study included 106 neonates of mothers with early-onset preeclampsia (developing at <34 weeks of gestation) and 106 infants of normotensive mothers, matched 1-to-1 for sex and gestational age. Serial blood pressure measurements were obtained on admission, daily for the first postnatal week, and then weekly up to the fourth week of life. RESULTS: There were no differences in blood pressure values on admission and the first day of life between cases and controls. Conversely, infants exposed to preeclampsia had significantly higher systolic (SBP), diastolic (DBP), and mean blood pressure (MBP) on the subsequent days up to the fourth postnatal week (P <.001-.033). Multiple regression analyses with adjustment for sex, gestational age, antenatal corticosteroid use, and maternal antihypertensive medication use confirmed the foregoing findings (P <.001-.048). Repeated-measures ANOVA also identified preeclampsia as a significant determinant of trends in SBP, DBP, and MBP during the first month of life (F = 16.2, P < .001; F = 16.4, P < .001; and F = 17.7, P < .001, respectively). CONCLUSIONS: Infants of mothers with early-onset preeclampsia have elevated blood pressure values throughout the neonatal period compared with infants born to normotensive mothers.


Assuntos
Diástole/fisiologia , Hipertensão/fisiopatologia , Pré-Eclâmpsia/fisiopatologia , Sístole/fisiologia , Adulto , Estudos de Casos e Controles , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Masculino , Gravidez , Estudos Prospectivos
14.
Arq. bras. cardiol ; 114(2): 284-292, Feb. 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1088875

RESUMO

Abstract Background: Diastolic dysfunction, commonly evaluated by echocardiography, is an important early finding in many cardiomyopathies. Cardiac magnetic resonance (CMR) often requires specialized sequences that extends the test time. Recently, feature-tracking imaging has been made available, but still requires expensive software and lacks clinical validation. Objective: To assess diastolic function in patients with aortic valve disease (AVD) and compare it with normal controls by evaluating left ventricular (LV) longitudinal displacement by CMR. Methods: We compared 26 AVD patients with 19 normal controls. Diastolic function was evaluated as LV longitudinal displacement in 4-chamber view cine-CMR images using steady state free precession (SSFP) sequence during the entire cardiac cycle with temporal resolution < 50 ms. The resulting plot of atrioventricular junction (AVJ) position versus time generated variables of AVJ motion. Significance level of p < 0.05 was used. Results: Maximum longitudinal displacement (0.12 vs. 0.17 cm), maximum velocity during early diastole (MVED, 0.6 vs. 1.4s-1), slope of the best-fit line of displacement in diastasis (VDS, 0.22 vs. 0.03s-1), and VDS/MVED ratio (0.35 vs. 0.02) were significantly reduced in AVD patients compared with controls, respectively. Aortic regurgitation showed significantly worse longitudinal LV shortening compared with aortic stenosis. Higher LV mass indicated worse diastolic dysfunction. Conclusions: A simple linear measurement detected significant differences on LV diastolic function between AVD patients and controls. LV mass was the only independent predictor of diastolic dysfunction in these patients. This method can help in the evaluation of diastolic dysfunction, improving cardiomyopathy detection by CMR, without prolonging exam time or depending on expensive software.


Resumo Fundamentos: A disfunção diastólica, comumente avaliada por ecocardiografia, é um importante achado precoce na maioria das cardiomiopatias. A ressonância magnética cardíaca (RMC) frequentemente requer sequências específicas que prolongam o tempo de exame. Recentemente, métodos de imagens com monitoramento de dados (feature-tracking) foram desenvolvidos, mas ainda requerem softwares caros e carecem de validação clínica. Objetivos: Avaliar a função diastólica em pacientes com doença valvar aórtica (DVA) e compará-la a controles normais pela medida do deslocamento longitudinal do ventrículo esquerdo (VE) por RMC. Métodos: Nós comparamos 26 pacientes com DVA com 19 controles normais. A função diastólica foi avaliada como uma medida do deslocamento longitudinal do VE nas imagens de cine-RMC no plano quatro câmaras usando a sequência steady state free precession (SSFP) durante todo o ciclo cardíaco com resolução temporal < 50 ms. O gráfico resultante da posição da junção atrioventricular versus tempo gerou variáveis de movimento da junção atrioventricular. Utilizamos nível de significância de p < 0,005. Resultados: Deslocamento longitudinal máximo (0,12 vs. 0,17 cm), velocidade máxima em início de diástole (0,6 vs. 1,4s-1), velocidade máxima na diástase (0,22 vs. 0,03s-1) e a razão entre a velocidade máxima na diástase e a velocidade máxima em diástole inicial (0,35 vs. 0,02) foram significativamente menores nos pacientes com DVA em comparação aos controles normais, respectivamente. Pacientes com insuficiência aórtica apresentaram medidas de encurtamento longitudinal do VE significativamente piores em comparação aqueles com estenose aórtica. O aumento da massa ventricular esquerda indicou pior disfunção diastólica. Conclusões: Esta simples medida linear detectou diferenças significativas na função diastólica do VE entre pacientes com DVA e controles normais. A massa ventricular esquerda foi o único preditor independente de disfunção diastólica nesses pacientes. Este método pode auxiliar na avaliação da disfunção diastólica, melhorando a detecção de cardiomiopatias por RMC sem prolongar o tempo de exame ou depender de caros softwares.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Insuficiência da Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/fisiopatologia , Disfunção Ventricular Esquerda/fisiopatologia , Diástole/fisiologia , Insuficiência da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/diagnóstico por imagem , Valores de Referência , Nó Atrioventricular/fisiopatologia , Nó Atrioventricular/diagnóstico por imagem , Fatores de Tempo , Fascículo Atrioventricular/fisiopatologia , Fascículo Atrioventricular/diagnóstico por imagem , Estudos de Casos e Controles , Modelos Lineares , Estudos Retrospectivos , Função Ventricular Esquerda/fisiologia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Estatísticas não Paramétricas , Imagem Cinética por Ressonância Magnética/métodos
15.
Int J Numer Method Biomed Eng ; 36(1): e3263, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31508895

RESUMO

The estimation of blood flow-induced loads occurring on the artery wall is affected by uncertainties hidden in the complex interaction of the pulsatile flow, the mechanical parameters of the artery, and the external support conditions. To circumvent these difficulties, a specific tool is developed by combining the aorta displacements measured by an electrocardiogram-gated-computed tomography angiography, with the blood velocity field computed by a smoothed particle hydrodynamics (SPH) numerical model. In the present work, the SPH model has been specifically adapted to the solution of the 3D Navier-Stokes equations inside a domain with boundaries of prescribed motion. Images of the abdominal aorta aneurysm (AAA) of a 44-year-old female patient were acquired during a stabilized cardiac cycle by electrocardiogram-gated-computed tomography angiography. The in vivo kinematic field inside the pulsating arterial wall was estimated by using recent technology, which makes it possible to follow the shape of the arterial wall during a cardiac cycle. We compare the flow conditions and the blood-induced loads, computed by the numerical model under the assumption of a moving arterial wall, with the corresponding results obtained assuming three rigid wall geometries of the vessel during the cardiac cycle. Significant differences were found for the wall shear stress distribution.


Assuntos
Algoritmos , Aneurisma da Aorta Abdominal/sangue , Aneurisma da Aorta Abdominal/fisiopatologia , Simulação por Computador , Hemodinâmica/fisiologia , Hidrodinâmica , Modelos Cardiovasculares , Estresse Mecânico , Fenômenos Biomecânicos , Velocidade do Fluxo Sanguíneo , Diástole/fisiologia , Humanos , Pressão , Fatores de Tempo
16.
Arq Bras Cardiol ; 114(2): 284-292, 2020 02.
Artigo em Inglês, Português | MEDLINE | ID: mdl-31553387

RESUMO

BACKGROUND: Diastolic dysfunction, commonly evaluated by echocardiography, is an important early finding in many cardiomyopathies. Cardiac magnetic resonance (CMR) often requires specialized sequences that extends the test time. Recently, feature-tracking imaging has been made available, but still requires expensive software and lacks clinical validation. OBJECTIVE: To assess diastolic function in patients with aortic valve disease (AVD) and compare it with normal controls by evaluating left ventricular (LV) longitudinal displacement by CMR. METHODS: We compared 26 AVD patients with 19 normal controls. Diastolic function was evaluated as LV longitudinal displacement in 4-chamber view cine-CMR images using steady state free precession (SSFP) sequence during the entire cardiac cycle with temporal resolution < 50 ms. The resulting plot of atrioventricular junction (AVJ) position versus time generated variables of AVJ motion. Significance level of p < 0.05 was used. RESULTS: Maximum longitudinal displacement (0.12 vs. 0.17 cm), maximum velocity during early diastole (MVED, 0.6 vs. 1.4s-1), slope of the best-fit line of displacement in diastasis (VDS, 0.22 vs. 0.03s-1), and VDS/MVED ratio (0.35 vs. 0.02) were significantly reduced in AVD patients compared with controls, respectively. Aortic regurgitation showed significantly worse longitudinal LV shortening compared with aortic stenosis. Higher LV mass indicated worse diastolic dysfunction. CONCLUSIONS: A simple linear measurement detected significant differences on LV diastolic function between AVD patients and controls. LV mass was the only independent predictor of diastolic dysfunction in these patients. This method can help in the evaluation of diastolic dysfunction, improving cardiomyopathy detection by CMR, without prolonging exam time or depending on expensive software.


Assuntos
Insuficiência da Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/fisiopatologia , Diástole/fisiologia , Disfunção Ventricular Esquerda/fisiopatologia , Adulto , Idoso , Insuficiência da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/diagnóstico por imagem , Nó Atrioventricular/diagnóstico por imagem , Nó Atrioventricular/fisiopatologia , Fascículo Atrioventricular/diagnóstico por imagem , Fascículo Atrioventricular/fisiopatologia , Estudos de Casos e Controles , Feminino , Humanos , Modelos Lineares , Imagem Cinética por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Estudos Retrospectivos , Estatísticas não Paramétricas , Fatores de Tempo , Disfunção Ventricular Esquerda/diagnóstico por imagem , Função Ventricular Esquerda/fisiologia
17.
Int J Cardiol ; 299: 257-262, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31350038

RESUMO

BACKGROUND: Hypertension is the most important risk factor for aortic dissection. We aimed to assess the association of systolic blood pressure (SBP) and diastolic blood pressure (DBP) at admission with aortic-related adverse events (ARAE) after thoracic endovascular aortic repair (TEVAR). METHODS: All patients (n = 269) admitted with type B aortic dissection (BAD) for TEVAR were included. ARAE at 3, 24, and 60 months were evaluated as outcomes. Cox proportional regression analysis was performed. RESULTS: No variables were found to be predictors of 3-month ARAE by multiple analysis. Independent predictors of 24-month ARAE were DBP at admission (hazard ratio [HR] per 10 mm Hg decrement, 1.318; 95% confidence interval [CI] 1.059-1.641; p = 0.013), cerebrovascular accident (HR 1.965; 95% CI 1.097-3.522; p = 0.023) and obesity (HR 2.922; 95% CI 1.096-7.795; p = 0.032). DBP at admission (HR per 10 mm Hg decrement, 1.276; 95% CI 1.038-1.569; p = 0.021) was also a predictor of 60-month ARAE. In the non-chronic group (n = 223), DBP at admission was evaluated as an independent predictor of 3-month (HR per 10 mm Hg decrement, 1.809; 95% CI 1.084-3.018; p = 0.023), 24-month (HR per 10 mm Hg decrement, 1.344; 95% CI 1.070-1.688; p = 0.011) and 60-month (HR per 10 mm Hg decrement, 1.338; 95% CI 1.065-1.682; p = 0.013) ARAE. In the chronic group (n = 46), no variables were found to be independent predictors of 3-month, 24-month, or 60-month ARAE. CONCLUSIONS: DBP at admission can predict ARAE in patients with BAD after TEVAR, whereas SBP was not associated with ARAE. The relationship between DBP at admission and outcomes appears to be more prominent in non-chronic patients.


Assuntos
Aneurisma Dissecante/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Pressão Sanguínea/fisiologia , Procedimentos Endovasculares/efeitos adversos , Admissão do Paciente/tendências , Complicações Pós-Operatórias/etiologia , Idoso , Aneurisma Dissecante/diagnóstico por imagem , Aneurisma Dissecante/fisiopatologia , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/fisiopatologia , Diástole/fisiologia , Procedimentos Endovasculares/tendências , Feminino , Seguimentos , Humanos , Hipertensão/diagnóstico por imagem , Hipertensão/fisiopatologia , Hipertensão/cirurgia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/fisiopatologia , Sístole/fisiologia
19.
Clin Exp Hypertens ; 42(2): 105-109, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30810396

RESUMO

Objective: For repeated measurements of blood pressure (BP) using the auscultatory method, current guidelines recommend intervals of 1-2 minutes; however, evidence to support this recommendation is insufficient. In the present study, the effects of intervals among repeated BP measurements using the auscultatory method were evaluated.Methods: Systolic and diastolic BPs were measured using the auscultatory method in 37 participants. The measurements were repeated 5 times each at intervals of 15, 30, 60, 90, and 120 seconds. The changes in the BP along with the increasing the number of repetitions were assessed at each measurement interval using a linear mixed model.Results: With an increasing number of measurements, the systolic and diastolic BPs showed significant progressive decrease and increase (p < 0.05), respectively, when the measurement interval was 15 seconds. However, the precision of BP measurements was not affected by performing the measurements at intervals of 30 seconds or longer.Conclusion: Repeated BP measurements using the auscultatory method need to have an interval of at least 30 seconds, which is shorter than the intervals recommended by the current guidelines.


Assuntos
Pressão Sanguínea/fisiologia , Hipertensão/diagnóstico , Adulto , Idoso , Auscultação/métodos , Determinação da Pressão Arterial/métodos , Coleta de Dados , Diástole/fisiologia , Feminino , Nível de Saúde , Humanos , Hipertensão/fisiopatologia , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Oscilometria/métodos , Sístole/fisiologia , Adulto Jovem
20.
Lasers Med Sci ; 35(5): 1041-1046, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31664552

RESUMO

The main purpose of this work was to construct an energy-dependent response curve of photobiomodulation on arterial pressure in hypertension animal model. To reach this objective, we have used a two-kidney one clip (2K-1C) rat model. Animals received acute laser light irradiation (660 nm) on abdominal region using different energy (0.6, 1.8, 3.6, 7.2, 13.8, 28.2, 55.8, and 111.6 J), the direct arterial pressure was measured by femoral cannulation, and systolic arterial pressure (SAP), diastolic arterial pressure (DAP), heart rate (HR), and time of effect were obtained. Our results indicated that 660 nm laser light presents an energy-dependent hypotensive effect, and 28.2 J energy irradiation reached the maximum hypotensive effect, inducing a decreased SAP, DAP, and HR (decrease in SAP: - 19.23 ± 1.82 mmHg, n = 11; DAP: - 9.57 ± 2.23 mmHg, n = 11; HR: - 39.15 ± 5.10 bpm, n = 11; and time of hypotensive effect: 3068.00 ± 719.00 s, n = 11). The higher energy irradiation evaluated (111.6 J) did not induce a hypotensive effect and induced an increase in HR (21.69 ± 7.89 bpm, n = 7). Taken together, our results indicate that red laser energy irradiation from 7.2 to 55.8 J is the effective therapeutic window to reduce SAP, DAP, MAP, and HR and induce a long-lasting hypotensive effect in rats, with effect loss at higher energy irradiation (111.6 J).


Assuntos
Pressão Sanguínea , Hipertensão/fisiopatologia , Hipertensão/radioterapia , Terapia com Luz de Baixa Intensidade , Animais , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Diástole/fisiologia , Frequência Cardíaca , Hipotensão/fisiopatologia , Masculino , Ratos Wistar , Sístole/fisiologia
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