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1.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 38(2): 310-316, 2021 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-33913291

RESUMO

This study aims to explore the intraventricular pressure difference (IVPD) within left ventricle in patients with paroxysmal atrial fibrillation (PAF) by using the relative pressure imaging (RPI) of vector flow mapping (VFM). Twenty patients with paroxysmal atrial fibrillation (PAF) and thirty control subjects were enrolled in the study. Systolic and diastolic IVPD derived from VFM within left ventricle and conventional echocardiographic parameters were analyzed. It was found that the B-A IVPD of left ventricle in PAF patients showed the same pattern as controls-single peak and single valley during systole and double peaks and double valleys during diastole. Basal IVPD was the main component of base to apex IVPD (B-A IVPD). The isovolumetric systolic IVPD was associated with early systolic IVPD, early systolic IVPD was associated with late systolic IVPD, and late systolic IVPD was associated with isovolumic diastolic IVPD (all P < 0.05). The B-A IVPD and basal IVPD during isovolumetric systole, early systole, late systole and isovolumetric diastole in PAF patients significantly decreased (all P < 0.05). The study shows that the B-A IVPD pattern of the PAF group is the same as controls, but systolic B-A IVPD and basal IVPD are significantly reduced in PAF patients. VFM-derived RPI can evaluate left ventricular IVPD in PAF patients, providing a visually quantitative method for evaluating left ventricular hemodynamic mechanics in the patients with PAF.


Assuntos
Fibrilação Atrial , Fibrilação Atrial/diagnóstico por imagem , Diástole , Ventrículos do Coração , Humanos , Função Ventricular Esquerda , Pressão Ventricular
2.
Int J Mol Sci ; 22(6)2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33802928

RESUMO

Blood platelets' adenosine receptors (AR) are considered to be a new target for the anti-platelet therapy. This idea is based on in vitro studies which show that signaling mediated by these receptors leads to a decreased platelet response to activating stimuli. In vivo evidence for the antithrombotic activity of AR agonists published to date were limited, however, to the usage of relatively high doses given in bolus. The present study was aimed at verifying if these substances used in lower doses in combination with inhibitors of P2Y12 could serve as components of dual anti-platelet therapy. We have found that a selective A2A agonist 2-hexynyl-5'-N-ethylcarboxamidoadenosine (HE-NECA) improved the anti-thrombotic properties of either cangrelor or prasugrel in the model of ferric chloride-induced experimental thrombosis in mice. Importantly, HE-NECA was effective not only when applied in bolus as other AR agonists in the up-to-date published studies, but also when given chronically. In vitro thrombus formation under flow conditions revealed that HE-NECA enhanced the ability of P2Y12 inhibitors to decrease fibrinogen content in thrombi, possibly resulting in their lower stability. Adenosine receptor agonists possess a certain hypotensive effect and an ability to increase the blood-brain barrier permeability. Therefore, the effects of anti-thrombotic doses of HE-NECA on blood pressure and the blood-brain barrier permeability in mice were tested. HE-NECA applied in bolus caused a significant hypotension in mice, but the effect was much lower when the substance was given in doses corresponding to that obtained by chronic administration. At the same time, no significant effect of HE-NECA was observed on the blood-brain barrier. We conclude that chronic administration of the A2A agonist can be considered a potential component of a dual antithrombotic therapy. However, due to the hypotensive effect of the substances, dosage and administration must be elaborated to minimize the side-effects. The total number of animals used in the experiments was 146.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Adenosina-5'-(N-etilcarboxamida)/análogos & derivados , Antitrombinas/farmacologia , Fibrinogênio/metabolismo , Cloridrato de Prasugrel/farmacologia , Agonistas do Receptor Purinérgico P1/farmacologia , Trombose/metabolismo , Monofosfato de Adenosina/farmacologia , Adenosina-5'-(N-etilcarboxamida)/farmacologia , Adulto , Animais , Pressão Sanguínea/efeitos dos fármacos , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/patologia , Cloretos , Diástole/efeitos dos fármacos , Feminino , Compostos Férricos , Humanos , Fluxometria por Laser-Doppler , Masculino , Camundongos Endogâmicos C57BL , Permeabilidade/efeitos dos fármacos , Ativação Plaquetária/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Antagonistas do Receptor Purinérgico P2Y/farmacologia , Sístole/efeitos dos fármacos
3.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 38(1): 138-144, 2021 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-33899438

RESUMO

Auscultation of heart sounds is an important method for the diagnosis of heart conditions. For most people, the audible component of heart sound are the first heart sound (S1) and the second heart sound (S2). Different diseases usually generate murmurs at different stages in a cardiac cycle. Segmenting the heart sounds precisely is the prerequisite for diagnosis. S1 and S2 emerges at the beginning of systole and diastole, respectively. Locating S1 and S2 accurately is beneficial for the segmentation of heart sounds. This paper proposed a method to classify the S1 and S2 based on their properties, and did not take use of the duration of systole and diastole. S1 and S2 in the training dataset were transformed to spectra by short-time Fourier transform and be feed to the two-stream convolutional neural network. The classification accuracy of the test dataset was as high as 91.135%. The highest sensitivity and specificity were 91.156% and 92.074%, respectively. Extracting the features of the input signals artificially can be avoid with the method proposed in this article. The calculation is not complicated, which makes this method effective for distinguishing S1 and S2 in real time.


Assuntos
Ruídos Cardíacos , Diástole , Coração , Redes Neurais de Computação , Rios
4.
Recenti Prog Med ; 112(3): 216-218, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33687360

RESUMO

We analysed RRI and other hemodynamic, re-spiratory and inflammation parameters in critically ill pa-tients affected by severe covid-19 with acute distress respi-ratory syndrome (ARDS) aiming at verifying their modifica-tions during supine and prone positioning and any mutual correlation or interplay with RRI.


Assuntos
Velocidade do Fluxo Sanguíneo , Inflamação/fisiopatologia , Rim/fisiopatologia , Pulmão/fisiopatologia , Artéria Renal/fisiopatologia , Circulação Renal , /fisiopatologia , Biomarcadores , Proteína C-Reativa/análise , /complicações , Creatinina/sangue , Diástole , Diagnóstico Precoce , Feminino , Humanos , Inflamação/sangue , Inflamação/diagnóstico , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Decúbito Ventral , /etiologia , Decúbito Dorsal , Sístole
5.
Kardiologiia ; 61(2): 62-68, 2021 Mar 06.
Artigo em Russo, Inglês | MEDLINE | ID: mdl-33734048

RESUMO

Aim      To determine diagnostic capabilities of the expanded protocol for stress echocardiography (stress-EchoCG) with comprehensive evaluation of clinical and echocardiographic indexes in differential diagnosis of dyspnea.Material and methods This study included 243 patients (123 women and 120 men) who were referred to outpatient stress-EchoCG during one calendar month. For 80 patients complaining about shortness of breath, the expanded stress-EchoCG protocol with treadmill exercise was performed. During the exercise, E / e' and tricuspid regurgitation velocity were determined, and clinical features and possible nature of dyspnea were evaluated.Results Shortness of breath had an ischemic origin in 17.5 % of 80 patients; 13.8 % had criteria of elevated left ventricular end-diastolic pressure; 17.5 % of patients had clinical signs of bronco-pulmonary pathology; 5.0 % had moderate and severe mitral regurgitation; 20 % displayed signs of chronotropic insufficiency during exercise including on the background of beta-blocker therapy; 15.0 % of patients displayed a hypertensive response to exercise, which was associated with signs of chronotropic insufficiency in 50 % of them; and 1.3 % had signs of hyperventilation syndrome. In addition to diagnosis of transient ischemia, additional information about the nature of shortness of breath was obtained for 72.5 % of patients. Based on results of the test, objective causes for dyspnea were not identified for 10.0 % of patients.Conclusion      The expanded stress-EchoCG protocol with exercise allows obtaining information about the nature of dyspnea for most patients with shortness of breath of a non-ischemic origin. For this patient category, expanding the stress-EchoCG protocol does not increase duration of the study and is economically beneficial for diagnosis of chronic heart failure and other causes for shortness of breath.


Assuntos
Ecocardiografia sob Estresse , Esforço Físico , Diástole , Dispneia/diagnóstico , Dispneia/etiologia , Teste de Esforço , Feminino , Humanos , Masculino , Função Ventricular Esquerda
6.
Kardiologiia ; 61(1): 66-71, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33706689

RESUMO

Goals Discrimination of the time course of functional recovery in early period following ST elevation myocardial infarction (STEMI) has prognostic importance. This study aims to establish the ability of the combined systolic-diastolic index (E / (Ea x Sa), for differentiating recoverable myocardium or persistent non-viability in subjects with STEMI.Material and methods 77 patients with first acute STEMI were enrolled to the study. Serial transthoracic echocardiography (TTE) examinations were performed at the time of the admission (immediately after reperfusion), hospital discharge (5±1 days) and control examination (30±2 days). To assess the association between E / (Ea×Sa) index and myocardial recovery, two categories (Transient stunning and persistent non-viability) were defined on basis of improvement of left ventricle ejection fraction (LV EF) (Improvement was defined as an increase more than 10 % in LV EF at day 30 compared to baseline).Results 55 patients (71.4 %) had improvement of LV EF and 24 patients (28.6 %) had no recovery of systolic function (30 days LV EF 48.78±6.1 vs. 39.31±8.1 %, p=0.01). The E / (Ea×Sa) index were significantly higher in the "non-viability" than in stunning group on predischarge and 1 month (1.61±0.64 vs 1.25±0.43, p=0.01 and 1.33±0.25 vs 1.14±0.21, p=0.01, respectively). The change in the E / (Ea×Sa) index in early period (within 5±1 days) was higher in the stunning group (26 %) compared to non-viability group (15 %) (p=0.033). E / (Ea×Sa) index was found to be a significant predictor of myocardial recovery in multivariable logistic regression (OR 0.91, 95 % CI 0.83-0.98, p=0.001). Roc curve showed that the cutoff value of E / (Ea×Sa) index is 1.29 with 73 % of sensitivity and 61 % of specificity (AUC: 0.71, p=0.01, CI: 0.54-0.89).Conclusions Our findings suggest that E / (Ea×Sa) index is a strong predictor of functional recovery; the odds of recovery decreases as E / (Ea×Sa) index value increases.


Assuntos
Infarto do Miocárdio com Supradesnível do Segmento ST , Diástole , Ecocardiografia , Humanos , Miocárdio , Valor Preditivo dos Testes , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Função Ventricular Esquerda
7.
Undersea Hyperb Med ; 48(1): 73-80, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33648036

RESUMO

Venous gas emboli (VGE) are often quantified as a marker of decompression stress on echocardiograms. Bubble-counting has been proposed as an easy to learn method, but remains time-consuming, rendering large dataset analysis impractical. Computer automation of VGE counting following this method has therefore been suggested as a means to eliminate rater bias and save time. A necessary step for this automation relies on the selection of a frame during late ventricular diastole (LVD) for each cardiac cycle of the recording. Since electrocardiograms (ECG) are not always recorded in field experiments, here we propose a fully automated method for LVD frame selection based on regional intensity minimization. The algorithm is tested on 20 previously acquired echocardiography recordings (from the original bubble-counting publication), half of which were acquired at rest (Rest) and the other half after leg flexions (Flex). From the 7,140 frames analyzed, sensitivity was found to be 0.913 [95% CI: 0.875-0.940] and specificity 0.997 [95% CI: 0.996-0.998]. The method's performance is also compared to that of random chance selection and found to perform significantly better (p≺0.0001). No trend in algorithm performance was found with respect to VGE counts, and no significant difference was found between Flex and Rest (p>0.05). In conclusion, full automation of LVD frame selection for the purpose of bubble counting in post-dive echocardiography has been established with excellent accuracy, although we caution that high quality acquisitions remain paramount in retaining high reliability.


Assuntos
Algoritmos , Diagnóstico por Computador/métodos , Mergulho/fisiologia , Ecocardiografia/métodos , Embolia Aérea/diagnóstico por imagem , Função Ventricular/fisiologia , Doença da Descompressão/diagnóstico por imagem , Diagnóstico por Computador/estatística & dados numéricos , Diástole/fisiologia , Ecocardiografia/estatística & dados numéricos , Ventrículos do Coração/diagnóstico por imagem , Humanos , Contração Miocárdica/fisiologia , Sensibilidade e Especificidade
8.
Pol Merkur Lekarski ; 49(289): 32-34, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33713090

RESUMO

Obesity is one of the most serious and common risk factors for cardiovascular disease that increases the risk of type 2 diabetes. AIM: The aim of the study was to analyze the features of disorders of diastolic function of the left ventricle and the oxygenation of arterial and venous blood in patients with diabetic foot syndrome and metabolic syndrome with diastolic dysfunction of the left ventricle in its complex treatment with the using a course of hyperbaric oxygen therapy. MATERIALS AND METHODS: An examination of 32 patients with diabetic foot syndrome, neuro-ischemic form (I stage - 8 patients, II stage - 24 patients) and metabolic syndrome, to determine an assessment was made of diastolic function of the left ventricle, determination of saturation of arterial and venous blood, oxygen content in arterial and venous blood, arterio-venous difference in oxygen. The control group consisted of 20 healthy individuals. These indicators were determined before starting the course of hyperbaric oxygen therapy and after completing the full course used 100 % oxygen, with the following parameters: working pressure of 1.7-1.8 at, with periods of compression and decompression of 10 minutes, isopression - 40-60 minutes. The total number of sessions was 8-10. RESULTS: The ratio peak rates of early- and late diastolic filling of the patients in the study group was significantly lower by 24.48 % (p <0.05) compared to the control group. Iso-volumetric relaxation and slowing of early diastolic filling also increased: by 21.02 % and by 7.26 % (p <0.05), respectively. Saturation of arterial blood after hyperbaric oxygenation sessions was 4.1% higher than the initial data. Saturation of venous blood before and after oxygen therapy was 52.64 ± 0.08 % and 58.25 ± 0.02 %, respectively. Oxygen content in arterial and venous blood before the start of the course was 121.57 ± 0.85 ml· L-1 and 127.20 ± 3.5 ml·L-1, respectively, and after treatment respectively 135.61 ± 0.06 ml·L-1 and 82.13 ± 0.01 ml·L-1. In addition, the volume of oxygen consumed by body tissues increased from 46.85 ± 0.84 ml·L-1 to 57.83 ± 4.3 ml·L-1. CONCLUSIONS: The use of the course of the hyperbaric oxygen therapy contributed to the reduction of signs of diastolic heart failure and increased oxygenation rates of arterial and venous blood, the alignment of oxygen metabolism, contributed to the elimination of both systemic oxygen deficiency and local tissue hypoxia, due to which a complex therapeutic effect revealed.


Assuntos
Diabetes Mellitus Tipo 2 , Pé Diabético , Síndrome Metabólica , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/terapia , Pé Diabético/terapia , Diástole , Ventrículos do Coração , Humanos , Síndrome Metabólica/complicações , Síndrome Metabólica/terapia
9.
J Comput Assist Tomogr ; 45(2): 242-247, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33661156

RESUMO

OBJECTIVES: We aimed to assess the agreement between cardiac computed tomography (CT) and echo for diagnosing advanced diastolic dysfunction (DD) and to assess the prognostic value of CT-based parameters. METHODS: One hundred one consecutive patients who had both CT and echo-Doppler within 1 month were included. Diastolic function was assessed by CT using a previously validated method, based on left atrial volume changes, and compared with echocardiography grades 0 to 3. Patients were followed up for a combined outcome of cardiac death and hospitalization for heart failure. RESULTS: By operating characteristic curve analysis, the best CT-based parameter for predicting advanced DD based on echo was left atrial total emptying fraction. Left atrial total emptying fraction <36% had sensitivity/specificity of 76%/86%. Agreement between echo and CT for detecting advanced (grades 2/3) DD was substantial (κ = 0.62, P < 0.0001). By Cox multivariate analysis, left atrial total emptying fraction was a powerful independent predictor of outcome at 3 years (hazard ratio, 8.0 [2.2-28.4]; P < 0.0001). CONCLUSIONS: Computed tomography-based assessment of DD has a good agreement with echo-Doppler-based results. Left atrial total emptying fraction seems to have a strong prognostic value.


Assuntos
Diástole/fisiologia , Ecocardiografia Doppler , Átrios do Coração/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Disfunção Ventricular/diagnóstico por imagem , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Sensibilidade e Especificidade , Resultado do Tratamento
10.
Am J Physiol Heart Circ Physiol ; 320(5): H1862-H1872, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33769915

RESUMO

There are currently no Food and Drug Administration-approved treatments for heart failure with preserved ejection fraction (HFpEF). Here we compared the effects of exercise with and without α/ß-adrenergic blockade with carvedilol in Col4a3-/- Alport mice, a model of the phenogroup 3 subclass of HFpEF with underlying renal dysfunction. Alport mice were assigned to the following groups: no treatment control (n = 29), carvedilol (n = 11), voluntary exercise (n = 9), and combination carvedilol and exercise (n = 8). Cardiac function was assessed by echocardiography after 4-wk treatments. Running activity of Alport mice was similar to wild types at 1 mo of age but markedly reduced at 2 mo (1.3 ± 0.40 vs. 4.5 ± 1.02 km/day, P < 0.05). There was a nonsignificant trend for increased running activity at 2 mo by carvedilol in the combination treatment group. Combination treatments conferred increased body weight of Col4a3-/- mice (22.0 ± 1.18 vs. 17.8 ± 0.29 g in untreated mice, P < 0.01), suggesting improved physiology, and heart rates declined by similar increments in all carvedilol-treatment groups. The combination treatment improved systolic parameters; stroke volume (30.5 ± 1.99 vs. 17.8 ± 0.77 µL, P < 0.0001) as well as ejection fraction and global longitudinal strain compared with controls. Myocardial performance index was normalized by all interventions (P < 0.0001). Elevated osteopontin plasma levels in control Alport mice were significantly lowered only by combination treatment, and renal function of the Alport group assessed by urine albumin creatinine ratio was significantly improved by all treatments. The results support synergistic roles for exercise and carvedilol to augment cardiac systolic function of Alport mice with moderately improved renal functions but no change in diastole.NEW & NOTEWORTHY In an Alport mouse model of heart failure with preserved ejection fraction (HFpEF), exercise and carvedilol synergistically improved systolic function without affecting diastole. Carvedilol alone or in combination with exercise also improved kidney function. Molecular analyses indicate that the observed improvements in cardiorenal functions were mediated at least in part by effects on serum osteopontin and related inflammatory cytokine cascades. The work presents new potential therapeutic targets and approaches for HFpEF.


Assuntos
Antagonistas Adrenérgicos beta/farmacologia , Carvedilol/farmacologia , Colágeno Tipo IV/deficiência , Terapia por Exercício , Insuficiência Cardíaca/terapia , Nefrite Hereditária/terapia , Osteopontina/sangue , Disfunção Ventricular Esquerda/terapia , Função Ventricular Esquerda/efeitos dos fármacos , Animais , Autoantígenos/genética , Biomarcadores/sangue , Colágeno Tipo IV/genética , Terapia Combinada , Diástole , Modelos Animais de Doenças , Regulação para Baixo , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/fisiopatologia , Camundongos da Linhagem 129 , Camundongos Knockout , Nefrite Hereditária/sangue , Nefrite Hereditária/genética , Nefrite Hereditária/fisiopatologia , Recuperação de Função Fisiológica , Sístole , Disfunção Ventricular Esquerda/sangue , Disfunção Ventricular Esquerda/genética , Disfunção Ventricular Esquerda/fisiopatologia
11.
J Vis Exp ; (168)2021 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-33645575

RESUMO

Scientific efforts in the field of computational modeling of cardiovascular diseases have largely focused on heart failure with reduced ejection fraction (HFrEF), broadly overlooking heart failure with preserved ejection fraction (HFpEF), which has more recently become a dominant form of heart failure worldwide. Motivated by the paucity of HFpEF in silico representations, two distinct computational models are presented in this paper to simulate the hemodynamics of HFpEF resulting from left ventricular pressure overload. First, an object-oriented lumped-parameter model was developed using a numerical solver. This model is based on a zero-dimensional (0D) Windkessel-like network, which depends on the geometrical and mechanical properties of the constitutive elements and offers the advantage of low computational costs. Second, a finite element analysis (FEA) software package was utilized for the implementation of a multidimensional simulation. The FEA model combines three-dimensional (3D) multiphysics models of the electro-mechanical cardiac response, structural deformations, and fluid cavity-based hemodynamics and utilizes a simplified lumped-parameter model to define the flow exchange profiles among different fluid cavities. Through each approach, both the acute and chronic hemodynamic changes in the left ventricle and proximal vasculature resulting from pressure overload were successfully simulated. Specifically, pressure overload was modeled by reducing the orifice area of the aortic valve, while chronic remodeling was simulated by reducing the compliance of the left ventricular wall. Consistent with the scientific and clinical literature of HFpEF, results from both models show (i) an acute elevation of transaortic pressure gradient between the left ventricle and the aorta and a reduction in the stroke volume and (ii) a chronic decrease in the end-diastolic left ventricular volume, indicative of diastolic dysfunction. Finally, the FEA model demonstrates that stress in the HFpEF myocardium is remarkably higher than in the healthy heart tissue throughout the cardiac cycle.


Assuntos
Análise de Elementos Finitos , Insuficiência Cardíaca/fisiopatologia , Modelos Cardiovasculares , Volume Sistólico/fisiologia , Estenose da Valva Aórtica/fisiopatologia , Diástole/fisiologia , Coração/fisiopatologia , Humanos
12.
Int J Nanomedicine ; 16: 1377-1390, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33658778

RESUMO

Background: Vascular drug delivery becomes a promising direction in the development of novel therapeutic strategies in the treatment of cardiovascular pathologies, such as hypertension. However, targeted delivery of hydrophobic substances, with poor bioavailability, remains a challenge. Here, we described the hypotensive effects of a low dose of curcumin delivered to the vascular wall using hyaluronic acid-based nanocapsules. Methods: The group of hypertensive TGR(m-Ren2)27 rats, was administrated respectively with the vehicle, curcumin solution or curcumin delivered using hyaluronic acid-based nanocapsules (HyC12-Cur), for 7 days each, maintaining the wash-out period between treatments. Arterial blood pressure (systolic - SBP, diastolic - DBP) and heart rate (HR) were monitored continuously using a telemetry system (Data Science International), and Mean Arterial Pressure (MAP) was calculated from SBP and DBP. Results: In hypertensive rats, a low dose of curcumin (4.5 mg/kg) administrated in HyC12-Cur for 7 days resulted in a gradual inhibition of SBP, DBP and MAP increase without an effect on HR. At the end of HyC12-Cur - based treatment changes in SBP, DBP and MAP amounted to -2.0±0.8 mmHg, -3.9±0.7 mmHg and -3.3±0.7 mmHg, respectively. In contrast, the administration of a curcumin solution (4.5 mg/kg) did not result in a significant hypotensive effect and the animals constantly developed hypertension. Vascular delivery of capsules with curcumin was confirmed using newly developed fluorine-rich nanocapsules (HyFC10-PFOB) with a shell based on a HA derivative and similar size as HyC12-Cur. HyFC10-PFOB gave fluorine signals in rat aortas analyzed ex vivo with a 19F NMR technique after a single intragastric administration. Conclusion: These results suggest that nanocapsules based on hyaluronic acid, the ubiquitous glycosaminoglycan of the extracellular matrix and an integral part of endothelial glycocalyx, may represent a suitable approach to deliver hydrophobic, poorly bioavailable compounds, to the vascular wall.


Assuntos
Curcumina/administração & dosagem , Curcumina/uso terapêutico , Ácido Hialurônico/química , Hipertensão/tratamento farmacológico , Nanocápsulas/química , Administração Oral , Animais , Aorta/efeitos dos fármacos , Aorta/patologia , Pressão Sanguínea/efeitos dos fármacos , Curcumina/farmacologia , Diástole/efeitos dos fármacos , Relação Dose-Resposta a Droga , Flúor/química , Frequência Cardíaca/efeitos dos fármacos , Hidrodinâmica , Interações Hidrofóbicas e Hidrofílicas , Hipertensão/fisiopatologia , Espectroscopia de Ressonância Magnética , Masculino , Tamanho da Partícula , Ratos , Eletricidade Estática , Sístole/efeitos dos fármacos
13.
Am J Physiol Heart Circ Physiol ; 320(4): H1535-H1542, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33577436

RESUMO

This study tested the hypothesis that early left ventricular (LV) relaxation is impaired in older obese patients with heart failure with preserved ejection fraction (HFpEF), and related to decreased peak exercise oxygen uptake (peak V̇o2). LV strain and strain rate were measured by feature tracking of magnetic resonance cine images in 79 older obese patients with HFpEF (mean age: 66 yr; mean body mass index: 38 kg/m2) and 54 healthy control participants. LV diastolic strain rates were indexed to cardiac preload as estimated by echocardiography derived diastolic filling pressures (E/e'), and correlated to peak V̇o2. LV circumferential early diastolic strain rate was impaired in HFpEF compared with controls (0.93 ± 0.05/s vs. 1.20 ± 0.07/s, P = 0.014); however, we observed no group differences in early LV radial or longitudinal diastolic strain rates. Isolating myocardial relaxation by indexing all three early LV diastolic strain rates (i.e. circumferential, radial, and longitudinal) to E/e' amplified the group difference in early LV diastolic circumferential strain rate (0.08 ± 0.03 vs. 0.13 ± 0.05, P < 0.0001), and unmasked differences in early radial and longitudinal diastolic strain rate. Moreover, when indexing to E/e', early LV diastolic strain rates from all three principal strains, were modestly related with peak V̇o2 (R = 0.36, -0.27, and 0.35, respectively, all P < 0.01); this response, however, was almost entirely driven by E/e' itself, (R = -0.52, P < 0.001). Taken together, we found that although LV relaxation is impaired in older obese patients with HFpEF, and modestly correlates with their severely reduced peak exercise V̇o2, LV filling pressures appear to play a much more important role in determining exercise intolerance.NEW & NOTEWORTHY Using a multimodal imaging approach to uncouple tissue deformation from atrial pressure, we found that left ventricular (LV) relaxation is impaired in older obese patients with HFpEF, but only modestly correlates with their severely reduced peak V̇o2. In contrast, the data show a much stronger relationship between elevated LV filling pressures and exercise intolerance, refocusing future therapeutic priorities.


Assuntos
Tolerância ao Exercício , Insuficiência Cardíaca/fisiopatologia , Obesidade/fisiopatologia , Volume Sistólico , Disfunção Ventricular Esquerda/fisiopatologia , Função Ventricular Esquerda , Idoso , Estudos de Casos e Controles , Diástole , Ecocardiografia Doppler , Teste de Esforço , Feminino , Insuficiência Cardíaca/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Obesidade/diagnóstico por imagem , Consumo de Oxigênio , Disfunção Ventricular Esquerda/diagnóstico por imagem , Pressão Ventricular
14.
Cochrane Database Syst Rev ; 2: CD008823, 2021 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-33630309

RESUMO

BACKGROUND: Increased physical activity has been recommended as an important lifestyle modification for the prevention and control of hypertension. Walking is a low-cost form of physical activity and one which most people can do. Studies testing the effect of walking on blood pressure have revealed inconsistent findings. OBJECTIVES: To determine the effect of walking as a physical activity intervention on blood pressure and heart rate. SEARCH METHODS: We searched the following databases up to March 2020: the Cochrane Hypertension Specialised Register, CENTRAL (2020, Issue 2), Ovid MEDLINE, Ovid Embase, CINAHL, PsycINFO, SPORTDiscus, PEDro, the WHO International Clinical Trials Registry Platform, and ClinicalTrials.gov. We also searched the following Chinese databases up to May 2020: Index to Taiwan Periodical Literature System; National Digital Library of Theses and Dissertation in Taiwan; China National Knowledge Infrastructure (CNKI) Journals, Theses & Dissertations; and Wanfang Medical Online. We contacted authors of relevant papers regarding further published and unpublished work. The searches had no language restrictions. SELECTION CRITERIA: Randomised controlled trials of participants, aged 16 years and over, which evaluated the effects of a walking intervention compared to non-intervention control on blood pressure and heart rate were included. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. Where data were not available in the published reports, we contacted authors. Pooled results for blood pressure and heart rate were presented as mean differences (MDs) between groups with 95% confidence intervals (CIs). We undertook subgroup analyses for age and sex. We undertook sensitivity analyses to assess the effect of sample size on our findings. MAIN RESULTS: A total of 73 trials met our inclusion criteria. These 73 trials included 5763 participants and were undertaken in 22 countries. Participants were aged from 16 to 84 years and there were approximately 1.5 times as many females as males. The characteristics of walking interventions in the included studies were as follows: the majority of walking interventions was at home/community (n = 50) but supervised (n = 36 out of 47 reported the information of supervision); the average intervention length was 15 weeks, average walking time per week was 153 minutes and the majority of walking intensity was moderate. Many studies were at risk of selection bias and performance bias. Primary outcome We found moderate-certainty evidence suggesting that walking reduces systolic blood pressure (SBP) (MD -4.11 mmHg, 95% CI -5.22 to -3.01; 73 studies, n = 5060). We found moderate-certainty evidence suggesting that walking reduces SBP in participants aged 40 years and under (MD -4.41 mmHg, 95% CI -6.17 to -2.65; 14 studies, n = 491), and low-certainty evidence that walking reduces SBP in participants aged 41 to 60 years (MD -3.79 mmHg, 95% CI -5.64 to -1.94, P < 0.001; 35 studies, n = 1959), and those aged 60 years of over (MD -4.30 mmHg, 95% CI -6.17 to -2.44, 24 studies, n = 2610). We also found low certainty-evidence suggesting that walking reduces SBP in both females (MD -5.65 mmHg, 95% CI -7.89 to -3.41; 22 studies, n = 1149) and males (MD -4.64 mmHg, 95% CI -8.69 to -0.59; 6 studies, n = 203). Secondary outcomes We found low-certainty evidence suggesting that walking reduces diastolic blood pressure (DBP) (MD -1.79 mmHg, 95% CI -2.51 to -1.07; 69 studies, n = 4711) and heart rate (MD -2.76 beats per minute (bpm), 95% CI -4.57 to -0.95; 26 studies, n = 1747). We found moderate-certainty evidence suggesting that walking reduces DBP for participants aged 40 years and under (MD -3.01 mmHg, 95% CI -4.44 to -1.58; 14 studies, n = 491) and low-certainty evidence suggesting that walking reduces DBP for participants aged 41 to 60 years (MD -1.74 mmHg, 95% CI -2.95 to -0.52; 32 studies, n = 1730) and those aged 60 years and over (MD -1.33 mmHg, 95% CI -2.40 to -0.26; 23 studies, n = 2490). We found moderate-certainty evidence that suggests walking reduces DBP for males (MD -2.54 mmHg, 95% CI -4.84 to -0.24; 6 studies, n = 203) and low-certainty evidence that walking reduces DBP for females (MD -2.69 mmHg, 95% CI -4.16 to -1.23; 20 studies, n = 1000). Only 21 included studies reported adverse events. Of these 21 studies, 16 reported no adverse events, the remaining five studies reported eight adverse events, with knee injury being reported five times. AUTHORS' CONCLUSIONS: Moderate-certainty evidence suggests that walking probably reduces SBP. Moderate- or low-certainty evidence suggests that walking may reduce SBP for all ages and both sexes. Low-certainty evidence suggests that walking may reduce DBP and heart rate. Moderate- and low-certainty evidence suggests walking may reduce DBP and heart rate for all ages and both sexes.


Assuntos
Pressão Sanguínea/fisiologia , Frequência Cardíaca/fisiologia , Hipertensão/terapia , Caminhada/fisiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Viés , Diástole , Feminino , Humanos , Traumatismos do Joelho/etiologia , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Sístole , Fatores de Tempo , Caminhada/classificação , Adulto Jovem
15.
JAMA Netw Open ; 4(2): e2037554, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33595663

RESUMO

Importance: Extremely low diastolic blood pressure has been reported to be associated with increased adverse cardiovascular events (ie, the diastolic J-shape phenomenon); however, current US guidelines recommend an intensive blood pressure target of less than 130/80 mm Hg without mentioning the lower limits of diastolic blood pressure. Objectives: To evaluate whether there is a diastolic J-shape phenomenon for patients with an treated systolic blood pressure of less than 130 mm Hg and to explore the safe and optimal diastolic blood pressure ranges for this patient population. Design, Setting, and Participants: This cohort study analyzed outcome data of patients at high cardiovascular risk who were randomized to intensive or standard blood pressure control and achieved treated systolic blood pressure of less than 130 mm Hg in the Systolic Blood Pressure Intervention Trial (SPRINT) and Action to Control Cardiovascular Risk in Diabetes-Blood Pressure (ACCORD-BP) trial. Data were collected from October 2010 to August 2015 (SPRINT) and from September 1999 to June 2009 (ACCORD-BP). Data were analyzed from January to May 2020. Exposure: Treated diastolic blood pressure, divided in intervals of less than 60, 60 to less than 70, 70 to less than 80, and 80 mm Hg and greater. Main Outcomes and Measures: The primary outcome was a composite of all-cause death, nonfatal myocardial infarction, and nonfatal stroke. A composite cardiovascular outcome, including cardiovascular death, nonfatal myocardial infarction, and nonfatal stroke, was among the key secondary outcomes. Results: A total of 7515 patients (mean [SD] age, 65.6 [8.7] years; 4553 [60.6%] men) were included in this analysis. The nominally lowest risk was observed at a diastolic blood pressure between 70 and 80 mm Hg for the primary outcome, the composite cardiovascular outcome, nonfatal myocardial infarction, and cardiovascular death. A mean diastolic blood pressure of less than 60 mm Hg was associated with significantly increased risk of the primary outcome (hazard ratio [HR], 1.46; 95% CI, 1.13-1.90; P = .004), the composite cardiovascular outcome (HR, 1.74; 95% CI, 1.26-2.41; P = .001), nonfatal myocardial infarction (HR, 1.73; 95% CI, 1.15-2.59; P = .008), and nonfatal stroke (HR, 2.67; 95% CI, 1.26-5.63; P = .01). Conclusions and Relevance: This cohort study found that lowering diastolic blood pressure to less than 60 mm Hg was associated with increased risk of cardiovascular events in patients with high cardiovascular risk and an treated systolic blood pressure less than 130 mm Hg. The finding that a diastolic blood pressure value between 70 and 80 mm Hg was an optimum target for this patient population merits further study.


Assuntos
Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea , Hipertensão/tratamento farmacológico , Mortalidade , Infarto do Miocárdio/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Doenças Cardiovasculares/mortalidade , Causas de Morte , Diástole , Feminino , Humanos , Hipertensão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Planejamento de Assistência ao Paciente , Modelos de Riscos Proporcionais , Risco , Sístole
17.
High Blood Press Cardiovasc Prev ; 28(2): 167-175, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33599965

RESUMO

INTRODUCTION: Sacubitril/valsartan (S-V) has been shown to reduce clinical outcomes in patients with heart failure with reduced ejection fraction (HFrEF). This benefit has been mostly attributed to an improvement in systolic function. AIM: This study aimed to evaluate longitudinal changes in several echocardiographic parameters of diastolic function in a cohort of patients with HFrEF receiving S-V. METHODS: Echocardiographic parameters of consecutive patients receiving S-V, such as diastolic dysfunction (DD) grade and other individual diastolic and systolic function parameters, were prospectively collected at baseline and at 6-month follow-up. New York Heart Association (NYHA) functional class was also recorded. RESULTS: 65 patients (73.9% males; 61.5 ± 13 years) with HFrEF in NYHA class II-IV were evaluated. There was a significant reduction in DD grade after treatment with maximal tolerated doses (p < 0.001). Patients with advanced DD showed the most significant improvements: 75% and 60% of patients with initial grade 3 and 2, respectively, had better grade after 6 months of S-V. Moreover, there was a reduction in E/e' ratio (p = 0.004), left atrial longitudinal strain (p = 0.002), and an improvement of left ventricle ejection fraction (p < 0.001) and NYHA functional class (p = 0.001). Among those subjects who improved their functional class, a higher percentage improved their DD grade (39.3%, p = 0.025) in comparison with those not improving their NYHA class (25%, p = 0.434). CONCLUSIONS: In addition to an improvement in systolic function parameters, patients with HFrEF receiving S-V improved their diastolic function. This echocardiographic improvement is particularly relevant in those patients with better NYHA class at 6-month follow-up.


Assuntos
Aminobutiratos/uso terapêutico , Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Neprilisina/antagonistas & inibidores , Inibidores de Proteases/uso terapêutico , Volume Sistólico/efeitos dos fármacos , Tetrazóis/uso terapêutico , Função Ventricular Esquerda/efeitos dos fármacos , Idoso , Aminobutiratos/efeitos adversos , Bloqueadores do Receptor Tipo 1 de Angiotensina II/efeitos adversos , Diástole , Combinação de Medicamentos , Ecocardiografia , Feminino , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Inibidores de Proteases/efeitos adversos , Recuperação de Função Fisiológica , Tetrazóis/efeitos adversos , Fatores de Tempo , Resultado do Tratamento
18.
Am J Cardiol ; 146: 62-68, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33539862

RESUMO

Current risk models have only limited accuracy in predicting transcatheter aortic valve Implantation (TAVI) outcomes and there is a paucity of clinical variables to guide patient management after the procedure. The prognostic impact of elevated left ventricular end-diastolic pressure (LVEDP) in TAVI patients is unknown. The aim of the present study was to evaluate the prognostic value of after-procedural LVEDP in patients who undewent TAVI. Consecutive patients with severe symptomatic aortic stenosis who undewent TAVI were divided into 2 groups according to after-procedural LVEDP above and below or equal 12 mm Hg. Collected data included baseline clinical, laboratory and echocardiographic variables. We evaluated the impact of elevated vs. normal LVEDP on in-hospital outcomes, short- and long-term mortality. Eight hundred forty-five patients were included in the study with complete in-hospital and late mortality data available for all survivors (median follow-up 29.5 months [IQR 16.5 to 48.0]). The mean age (±SD) was 82.3±6.2 years and mean Society of Thoracic Surgery score was 4.0%±3.0%. Patients with LVEDP>12 mm Hg (n = 591, 70%) and LVEDP≤12 mm Hg (n = 254, 30%) had a 6-months mortality rate of 6.8% and 2%, respectively (P=0.004) and a 1-year mortality rate of 10.1% vs 4.9%, respectively (p = 0.017). By multivariable analysis, after-procedural LVEDP>12 mm Hg was independently associated with all-cause mortality (HR 2.45, 95% CI 1.58 to 3.76, p <0.001) during long-term follow-up. In conclusion, elevated after-procedural LVEDP in patients who undewent TAVI is an independent predictor of mortality following TAVI. Further research regarding the use of LVEDP as a tool for after-procedural medical management is warranted.


Assuntos
Estenose da Valva Aórtica/cirurgia , Valva Aórtica/cirurgia , Volume Sistólico/fisiologia , Substituição da Valva Aórtica Transcateter/métodos , Função Ventricular Esquerda/fisiologia , Pressão Ventricular/fisiologia , Idoso de 80 Anos ou mais , Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/diagnóstico , Estenose da Valva Aórtica/fisiopatologia , Diástole , Ecocardiografia , Feminino , Seguimentos , Humanos , Masculino , Período Pós-Operatório , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento
19.
Curr Opin Cardiol ; 36(2): 205-210, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33394713

RESUMO

PURPOSE OF REVIEW: Pulmonary hypertension (PH) occurs frequently in heart failure (HF) and confers worse prognosis. It becomes important to adequately identify these patients to optimize treatment. The purpose of this review is to inform about the updated classification of PH in left heart disease, in addition to current and upcoming trials regarding treatment. RECENT FINDINGS: The updated classification of PH due to left heart disease now utilizes pulmonary vascular resistance instead of diastolic pulmonary gradient to differentiate between isolated postcapillary and combined pre and postcapillary PH. In regards to treatment, recent clinical trials continue to provide data that pulmonary vasodilators do not improve outcomes in this population. SUMMARY: Management of underlying heart disease and optimal control of comorbidities continues to be the mainstay of treatment in PH due to HF. At this time, current data does not support the use of PH-directed therapies.


Assuntos
Cardiopatias , Insuficiência Cardíaca , Hipertensão Pulmonar , Diástole , Insuficiência Cardíaca/complicações , Humanos , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/etiologia , Resistência Vascular
20.
Am J Physiol Heart Circ Physiol ; 320(3): H1112-H1123, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33449850

RESUMO

Comprehensive functional characterization of cardiac tissue includes investigation of length and load dependence. Such measurements have been slow to develop in engineered heart tissues (EHTs), whose mechanical characterizations have been limited primarily to isometric and near-isometric behaviors. A more realistic assessment of myocardial function would include force-velocity curves to characterize power output and force-length loops mimicking the cardiac cycle to characterize work output. We developed a system that produces force-velocity curves and work loops in human EHTs using an adaptive iterative control scheme. We used human EHTs in this system to perform a detailed characterization of the cardiac ß-myosin specific inhibitor, mavacamten. Consistent with the clinically proposed application of this drug to treat hypertrophic cardiomyopathy, our data support the premise that mavacamten improves diastolic function through reduction of diastolic stiffness and isometric relaxation time. Meanwhile, the effects of mavacamten on length- and load-dependent muscle performance were mixed. The drug attenuated the length-dependent response at small stretch values but showed normal length dependency at longer lengths. Peak power output of mavacamten-treated EHTs showed reduced power output as expected but also shifted peak power output to a lower load. Here, we demonstrate a robust method for the generation of isotonic contraction series and work loops in engineered heart tissues using an adaptive-iterative method. This approach reveals new features of mavacamten pharmacology, including previously unappreciated effects on intrinsic myosin dynamics and preservation of Frank-Starling behavior at longer muscle lengths.NEW & NOTEWORTHY We applied innovative methods to comprehensively characterize the length and load-dependent behaviors of engineered human cardiac muscle when treated with the cardiac ß-myosin specific inhibitor mavacamten, a drug on the verge of clinical implementation for hypertrophic cardiomyopathy. We find mechanistic support for the role of mavacamten in improving diastolic function of cardiac tissue and note novel effects on work and power.


Assuntos
Benzilaminas/farmacologia , Inibidores Enzimáticos/farmacologia , Coração/efeitos dos fármacos , Contração Miocárdica/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Engenharia Tecidual , Uracila/análogos & derivados , Função Ventricular/efeitos dos fármacos , Miosinas Ventriculares/antagonistas & inibidores , Animais , Linhagem Celular , Diástole , Humanos , Modelos Cardiovasculares , Força Muscular/efeitos dos fármacos , Miócitos Cardíacos/enzimologia , Sus scrofa , Técnicas de Cultura de Tecidos , Tecidos Suporte , Uracila/farmacologia , Miosinas Ventriculares/metabolismo
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