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1.
Braz J Med Biol Res ; 53(3): e8761, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32159612

RESUMO

Nitric oxide (NO) inhibition by high-dose NG-nitro-L-arginine methyl ester (L-NAME) is associated with several detrimental effects on the cardiovascular system. However, low-dose L-NAME increases NO synthesis, which in turn induces physiological cardiovascular benefits, probably by activating a protective negative feedback mechanism. Aerobic exercise, likewise, improves several cardiovascular functions in healthy hearts, but its effects are not known when chronically associated with low-dose L-NAME. Thus, we tested whether the association between low-dose L-NAME administration and chronic aerobic exercise promotes beneficial effects to the cardiovascular system, evaluating the cardiac remodeling process. Male Wistar rats were randomly assigned to control (C), L-NAME (L), chronic aerobic exercise (Ex), and chronic aerobic exercise associated to L-NAME (ExL). Aerobic training was performed with progressive intensity for 12 weeks; L-NAME (1.5 mg·kg-1·day-1) was administered by orogastric gavage. Low-dose L-NAME alone did not change systolic blood pressure (SBP), but ExL significantly increased SBP at week 8 with normalization after 12 weeks. Furthermore, ExL promoted the elevation of left ventricle (LV) end-diastolic pressure without the presence of cardiac hypertrophy and fibrosis. Time to 50% shortening and relaxation were reduced in ExL, suggesting a cardiomyocyte contractile improvement. In addition, the time to 50% Ca2+ peak was increased without alterations in Ca2+ amplitude and time to 50% Ca2+ decay. In conclusion, the association of chronic aerobic exercise and low-dose L-NAME prevented cardiac pathological remodeling and induced cardiomyocyte contractile function improvement; however, it did not alter myocyte affinity and sensitivity to intracellular Ca2+ handling.


Assuntos
Cálcio/análise , Inibidores Enzimáticos/farmacologia , Contração Miocárdica/efeitos dos fármacos , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase/efeitos dos fármacos , Condicionamento Físico Animal/fisiologia , Adiposidade , Animais , Peso Corporal/fisiologia , Inibidores Enzimáticos/administração & dosagem , Hemodinâmica , Masculino , Modelos Animais , Atividade Motora/fisiologia , Miocárdio/patologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/fisiologia , NG-Nitroarginina Metil Éster/administração & dosagem , Óxido Nítrico Sintase/metabolismo , Ratos Wistar , Pressão Ventricular/efeitos dos fármacos
3.
Acta Cir Bras ; 34(8): e201900807, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31618407

RESUMO

PURPOSE: To investigate the effect of tanshinone IIA (TIIA) on ventricular remodeling in rats with pressure overload-induced heart failure. METHODS: Pressure overload-induced heart failure model (abdominal aortic coarctation) was established in 40 rats, which were divided into model and 5, 10 and 20 mg/kg TIIA groups. Ten rats receiving laparotomy excepting abdominal aortic coarctation were enrolled in sham-operated group. The 5, 10 and 20 mg/kg TIIA groups were treated with 5, 10 and 20 mg/kg TIIA, respectively, for 8 weeks. RESULTS: Compared with model group, in 20 mg/kg TIIA group the left ventricular ejection fraction, left ventricular fractional shortening, left ventricular systolic pressure, ±maximum left ventricular pressure rising and dropping rate, and myocardial B-cell lymphoma-2 and cleaved cysteinyl aspartate specific proteinase-3 protein levels were increased, respectively (P<0.05), and the left ventricular end diastolic diameter, left ventricular end systolic diameter, left ventricular end diastolic pressure, heart weight index, left ventricular weight index, serum B-type brain natriuretic peptide, interleukin 6 and C-reactive protein levels and myocardial B-cell lymphoma-2 associated X protein level were decreased, respectively (P<0.05). CONCLUSION: TIIA may alleviate ventricular remodeling in rats with pressure overload-induced heart failure heart by reducing inflammatory response and cardiomyocyte apoptosis.


Assuntos
/farmacologia , Insuficiência Cardíaca/fisiopatologia , Coração/efeitos dos fármacos , Imunossupressores/farmacologia , Remodelação Ventricular/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Ventrículos do Coração/fisiopatologia , Masculino , Distribuição Aleatória , Ratos , Pressão Ventricular
5.
Cardiol Young ; 29(10): 1248-1256, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31477187

RESUMO

BACKGROUND: While echocardiographic parameters are used to quantify ventricular function in infants with single ventricle physiology, there are few data comparing these to invasive measurements. This study correlates echocardiographic measures of diastolic function with ventricular end-diastolic pressure in infants with single ventricle physiology prior to superior cavopulmonary anastomosis. METHODS: Data from 173 patients enrolled in the Pediatric Heart Network Infant Single Ventricle enalapril trial were analysed. Those with mixed ventricular types (n = 17) and one outlier (end-diastolic pressure = 32 mmHg) were excluded from the analysis, leaving a total sample size of 155 patients. Echocardiographic measurements were correlated to end-diastolic pressure using Spearman's test. RESULTS: Median age at echocardiogram was 4.6 (range 2.5-7.4) months. Median ventricular end-diastolic pressure was 7 (range 3-19) mmHg. Median time difference between the echocardiogram and catheterisation was 0 days (range -35 to 59 days). Examining the entire cohort of 155 patients, no echocardiographic diastolic function variable correlated with ventricular end-diastolic pressure. When the analysis was limited to the 86 patients who had similar sedation for both studies, the systolic:diastolic duration ratio had a significant but weak negative correlation with end-diastolic pressure (r = -0.3, p = 0.004). The remaining echocardiographic variables did not correlate with ventricular end-diastolic pressure. CONCLUSION: In this cohort of infants with single ventricle physiology prior to superior cavopulmonary anastomosis, most conventional echocardiographic measures of diastolic function did not correlate with ventricular end-diastolic pressure at cardiac catheterisation. These limitations should be factored into the interpretation of quantitative echo data in this patient population.


Assuntos
Cateterismo Cardíaco/métodos , Ecocardiografia Doppler/métodos , Enalapril/uso terapêutico , Cardiopatias Congênitas/diagnóstico , Ventrículos do Coração/anormalidades , Função Ventricular Esquerda/fisiologia , Pressão Ventricular/fisiologia , Anti-Hipertensivos/uso terapêutico , Diástole , Método Duplo-Cego , Feminino , Seguimentos , Cardiopatias Congênitas/tratamento farmacológico , Cardiopatias Congênitas/fisiopatologia , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos
7.
Int J Cardiovasc Imaging ; 35(12): 2157-2166, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31346831

RESUMO

2016 guidelines for the echographic evaluation of left ventricular filling pressure (LVFP) proposed a single algorithm with limited number of criteria (E/A ratio, tricuspid regurgitation velocity, left atrial volume index and average E/e') mainly related to left atrial pressure. Pulmonary venous flow analysis, evaluating more specifically left ventricular end diastolic pressure (LVEDP) has been withdrawn. We aim to evaluate the proportion of patients diagnosed with normal LVFP according to 2016 recommendations, despite an abnormal pulmonary venous flow profile suggesting high LVEDP. We prospectively studied patients with stable ischemic cardiomyopathy and aortic stenosis, before cardiac surgery. Extensive echocardiography was performed including pulmonary and mitral A wave durations. We included 76 patients (mean age 72 ± 10 years, 78% were men), 37 (49%) with aortic stenosis and 22 (29%) with ischemic cardiomyopathy. Mean left ventricular ejection fraction was 67 ± 11%. Applying recommendations, 58 patients had normal LVFP and 15 patients had high LVFP. Among the 58 patients with normal LVFP, 26 patients had Apd-Amd duration > 30 ms highly suggestive of high LVEDP. These patients had higher LV mass (112 ± 30 g/m2 vs. 86 ± 20 g/m2, p = 0.004) and shorter A wave duration (120 ± 13.6 ms vs. 132 ± 16.5 ms, p = 0.006) as compared to the remaining 15 patients with concordant evaluation (normal LVFP and normal Apd-Amd). In the present study, we found that 26/58 patients with low LVFP according to the 2016 recommendations had Apd-Amd suggestive of high LVEDP. Pulmonary venous flow should be added to the algorithm, particularly in patients with unexplained symptom, high LV mass or truncated mitral A wave.


Assuntos
Estenose da Valva Aórtica/diagnóstico por imagem , Cardiomiopatias/diagnóstico por imagem , Ecocardiografia Doppler/normas , Fidelidade a Diretrizes/normas , Guias de Prática Clínica como Assunto/normas , Disfunção Ventricular Esquerda/diagnóstico por imagem , Função Ventricular Esquerda , Pressão Ventricular , Idoso , Idoso de 80 Anos ou mais , Estenose da Valva Aórtica/fisiopatologia , Cardiomiopatias/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes , Disfunção Ventricular Esquerda/fisiopatologia
8.
Am J Cardiol ; 124(3): 325-333, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31151655

RESUMO

The inter-relationships between minimal and maximal left atrial volume index (LAVI), left ventricular filling pressures and survival have not been well studied. This study aimed to compare LAVImin with LAVImax with respect to (1) relative prognostic value, and (2) correlation with left ventricular end-diastolic pressures (LVEDP), in patients with myocardial infarction (MI). A retrospective study involving consecutive patients with a first-ever MI (n = 419) was undertaken. LAVIs were determined using Simpson's biplane method from 2D echocardiography performed the day after admission. LAVmin ≥ 18 mls/m2 and LAVImax ≥ 34 mls/m2 were considered enlarged. The primary end point was composite major adverse cardiovascular events (MACE) (death/MI/heart failure). Correlation between LVEDP and LAVI was assessed in 120 patients who underwent echocardiography and cardiac catheterization either simultaneously (n = 30) or same-day (n = 90). At a median follow-up of 24 months, there were 61 MACE events. On Cox proportional hazards multivariate analysis incorporating significant clinical predictors and LVEF, whereas both LAVImin ≥ 18 mls/m2 (hazard ratio 3.15 [95% confidence interval 1.70 to 5.54], p <0.001) and LAVImax ≥ 34 mls/m2 (hazard ratio 1.79 [95% confidence interval 1.02 to 3.14], p = 0.041) were independent predictors of MACE, LAVImin showed a stronger association. Intermodel comparisons of the model chi-square and Harrell's C-statistic confirmed better prognostication with LAVImin. In the invasive cohort, because LAVImin and LAVImax had a similar correlation with LVEDP ≥ 15 mm Hg (r = 0.41 [p <0.001] vs r = 0.42 [p <0.001]), LAVmin ≥ 18 mls/m2 had a greater sensitivity for LVEDP ≥ 15 mm Hg than LAVImax ≥ 34 mls/m2 (sensitivity 59.4% vs 34.4%). In conclusion, utilizing thresholds of ≥18 and ≥34 mls/m2, respectively, LAVImin was a better predictor of survival than LAVImax, the pathophysiologic basis of which relates to a better sensitivity for elevated left ventricular filling pressures with LAVImin at these thresholds. There may be incremental clinical value in measuring LAVImin alongside LAVImax.


Assuntos
Átrios do Coração/diagnóstico por imagem , Infarto do Miocárdio/terapia , Função Ventricular Esquerda/fisiologia , Pressão Ventricular/fisiologia , Cateterismo Cardíaco , Doenças Cardiovasculares/mortalidade , Diástole/fisiologia , Ecocardiografia , Feminino , Insuficiência Cardíaca/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Infarto do Miocárdio/epidemiologia , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Sensibilidade e Especificidade
10.
Int J Cardiovasc Imaging ; 35(9): 1627-1636, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31041633

RESUMO

Intraventricular velocity distribution reflects left ventricular (LV) diastolic function and can be measured non-invasively by flow mapping technologies. We designed our study to compare intraventricular velocities and gradients, obtained by vector flow mapping (VFM) technology during early diastole in consecutive patients diagnosed with mild and advanced diastolic dysfunction at echocardiography and a control group with a purpose to validate the hypothesis of relationship between new parameters and severity of diastolic dysfunction and conventional markers of elevated LV filling pressure. Two-dimensional streamline fields were obtained using VFM technology in 121 subjects (57 with normal diastolic function, 38 with mild diastolic dysfunction and 26 with advanced diastolic dysfunction). We measured several velocities and calculated a gradient along the selected streamline, which we compared between groups and correlated them with conventional echocardiographic parameters. Apical intraventricular velocity gradient (GrIV) was the lowest in control group, followed by mild and advanced diastolic dysfunction groups (5.3 ± 1.9 vs. 6.8 ± 2.5 vs. 13.6 ± 5.0/s, p < 0.001) and showed good correlation with E/e' (r = 0.751, p < 000.1). GrIV/e' ratio was the strongest single predictor of severity of diastolic dysfunction. Different degrees of diastolic dysfunction affect the Intraventricular velocity behavior during early diastole obtained by VFM. GrIV could discriminate between groups with different levels of diastolic dysfunction and was closely associated with classical echocardiographic indices of elevated LV filling pressure. GrIV/e' ratio has a potential to become a single parameter needed to assess left ventricular diastolic function.


Assuntos
Ecocardiografia Doppler em Cores/métodos , Ecocardiografia Doppler de Pulso/métodos , Interpretação de Imagem Assistida por Computador/métodos , Disfunção Ventricular Esquerda/diagnóstico por imagem , Função Ventricular Esquerda , Pressão Ventricular , Adulto , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos , Estudos de Casos e Controles , Diástole , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Dados Preliminares , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Disfunção Ventricular Esquerda/fisiopatologia
11.
Clin Physiol Funct Imaging ; 39(5): 297-307, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31136072

RESUMO

AIM: This meta-analysis assesses left atrial (LA) cavity and myocardial function measurements that predict pulmonary capillary wedge pressure (PCWP). METHODS: PubMed-MEDLINE, EMBASE, Scopus, Google Scholar and the Cochrane Central Registry were searched up to December 2018 for studies on the relationship of LA diameter, LA indexed volume (LAVI max, LAVI min), peak atrial longitudinal (PALS), peak atrial contraction (PACS) strain and total emptying fraction (LAEF) with PCWP. Eighteen studies with 1343 patients were included. Summary sensitivity and specificity (with 95% CI) for evaluation of diagnostic accuracy and the best cut-off values for different LA indices in predicting raised PCWP were estimated using summary receiver operating characteristic analysis. RESULTS: The pooled analysis showed association between PCWP and LA diameter: Cohen's d = 0·87, LAVI max: d = 0·92 and LAVI min: d = 1·0 (P<0·001 for all). A stronger correlation was found between PCWP and PALS: d = 1·26, and PACS: d = 1·62, total EF d = 1·22 (P<0·0001 for all). PALS ≤19% had a summary sensitivity of 80% (65-90) and summary specificity of 77% (52-92), positive likelihood ratio (LR+) 3·74, negative likelihood ratio (LR-) <0·25 and DOR > 15·1 whereas LAVI ≥34 ml m-2 had summary sensitivity of 75% (55-89) and summary specificity 77% (57-90), with LR+ >3, LR- 0·32 and DOR >10·1. CONCLUSIONS: Compromised LA myocardial function and increased size predict raised cavity pressure. These results should assist in optimum follow-up of patients with fluctuating LA pressure.


Assuntos
Função do Átrio Esquerdo , Pressão Atrial , Remodelamento Atrial , Ecocardiografia , Átrios do Coração/diagnóstico por imagem , Cardiopatias/diagnóstico por imagem , Pressão Propulsora Pulmonar , Idoso , Cateterismo Cardíaco , Feminino , Átrios do Coração/fisiopatologia , Cardiopatias/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Função Ventricular Esquerda , Pressão Ventricular
12.
Cardiovasc Diabetol ; 18(1): 55, 2019 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-31039778

RESUMO

BACKGROUND: Liraglutide is an antidiabetic agent with cardioprotective effect. The purpose of this study is to test efficacy of liraglutide to improve diabetic cardiomyopathy in patients with diabetes mellitus type 2 (DM2) without cardiovascular disease. METHODS: Patients with DM2 were randomly assigned to receive liraglutide 1.8 mg/day or placebo in this double-blind trial of 26 weeks. Primary outcome measures were LV diastolic function (early (E) and late (A) transmitral peak flow rate, E/A ratio, early deceleration peak (Edec), early peak mitral annular septal tissue velocity (Ea) and estimated LV filling pressure (E/Ea), and systolic function (stroke volume, ejection fraction, cardiac output, cardiac index and peak ejection rate) assessed with CMR. Intention-to-treat analysis of between-group differences was performed using ANCOVA. Mean estimated treatment differences (95% confidence intervals) are reported. RESULTS: 23 patients were randomized to liraglutide and 26 to placebo. As compared with placebo, liraglutide significantly reduced E (- 56 mL/s (- 91 to - 21)), E/A ratio (- 0.17 (- 0.27 to - 0.06)), Edec (- 0.9 mL/s2 * 10-3 (- 1.3 to - 0.2)) and E/Ea (- 1.8 (- 3.0 to - 0.6)), without affecting A (3 mL/s (- 35 to 41)) and Ea (0.4 cm/s (- 0.9 to 1.4)). Liraglutide reduced stroke volume (- 9 mL (- 16 to - 2)) and ejection fraction (- 3% (- 6 to - 0.1)), but did not change cardiac output (- 0.4 L/min (- 0.9 to 0.2)), cardiac index (- 0.1 L/min/m2 (- 0.4 to 0.1)) and peak ejection rate (- 46 mL/s (- 95 to 3)). CONCLUSIONS: Liraglutide reduced early LV diastolic filling and LV filling pressure, thereby unloading the left ventricle. LV systolic function reduced and remained within normal range. Future studies are needed to investigate if liraglutide-induced left ventricular unloading slows progression of diabetic cardiomyopathy into symptomatic stages. Trial registration ClinicalTrials.gov: NCT01761318.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Cardiomiopatias Diabéticas/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Liraglutida/uso terapêutico , Volume Sistólico/efeitos dos fármacos , Disfunção Ventricular Esquerda/tratamento farmacológico , Função Ventricular Esquerda/efeitos dos fármacos , Pressão Ventricular/efeitos dos fármacos , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/diagnóstico por imagem , Diabetes Mellitus Tipo 2/fisiopatologia , Cardiomiopatias Diabéticas/sangue , Cardiomiopatias Diabéticas/diagnóstico por imagem , Cardiomiopatias Diabéticas/fisiopatologia , Método Duplo-Cego , Feminino , Humanos , Hipoglicemiantes/efeitos adversos , Liraglutida/efeitos adversos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Países Baixos , Recuperação de Função Fisiológica , Fatores de Tempo , Resultado do Tratamento , Disfunção Ventricular Esquerda/sangue , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia , Adulto Jovem
13.
Cardiovasc Ultrasound ; 17(1): 6, 2019 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-30954080

RESUMO

BACKGROUND: The contractile response of patients with heart failure (HF) may be assessed by exercise stress echocardiography (ESE)-derived indexes. We sought to test whether ESE parameters are useful to identify the risk of adverse left ventricular (LV) remodeling in patients with chronic HF and reduced or mildly reduced LV ejection fraction (EF). METHODS: We enrolled 155 stabilized patients (age: 62 ± 11 years, 17% female, coronary artery disease 47%) with chronic HF, LV EF ≤50% and LV end-diastolic volume index > 75 ml/m2. All patients underwent a symptom-limited graded bicycle semi-supine ESE, with evaluation of peak stress LV EF, end-systolic pressure-volume relation (ESPVR, i.e. LV elastance) and cardiac power output to LV mass (CPOM). A complete echocardiographic study was performed at baseline and after 6 ± 3 months. Adverse LV remodeling was defined as the association of eccentric LV hypertrophy (LV mass: ≥115 g/m2 for male and ≥ 95 g/m2 for women, and relative wall thickness < 0.32) with an increase in LV end-systolic volume index ≥10% at six months. RESULTS: Adverse LV remodeling was detected in 34 (22%) patients. After adjustment for clinical, biochemical and echocardiographic data, peak ESPVR resulted in the most powerful independent predictor of adverse LV remodeling (OR: 12.5 [95% CI 4.5-33]; p < 0.0001) followed by ischemic aetiology (OR: 2.64 [95% 1.04-6.73]; p = 0.04). CONCLUSION: In patients with HF and reduced or mildly reduced EF, a compromised ESE-derived peak ESPVR, that reflects impaired LV contractility, resulted to be the most powerful predictor of adverse LV remodeling.


Assuntos
Ecocardiografia sob Estresse/métodos , Insuficiência Cardíaca/diagnóstico , Ventrículos do Coração/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/diagnóstico , Volume Sistólico/fisiologia , Pressão Ventricular/fisiologia , Remodelação Ventricular/fisiologia , Idoso , Feminino , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/fisiopatologia , Ventrículos do Coração/fisiopatologia , Humanos , Hipertrofia Ventricular Esquerda/complicações , Hipertrofia Ventricular Esquerda/fisiopatologia , Masculino , Pessoa de Meia-Idade , Função Ventricular Esquerda/fisiologia
14.
J Cardiovasc Med (Hagerstown) ; 20(6): 389-396, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30994509

RESUMO

AIMS: Left ventricular outflow tract (LVOT) obstruction is a key feature of hypertrophic cardiomyopathy (HCM) that identifies patients at increased risk of adverse outcomes. Previous studies have hypothesized that LVOT obstruction enhances myocardial fibrosis and increases left ventricular (LV) filling pressures, producing greater clinical deterioration. However, this hypothesis has not been demonstrated in a clinical cohort comparing obstructive and nonobstructive patients. METHODS: Patients with HCM in whom Doppler echocardiography was performed within 30 days of cardiac MRI were enrolled, using the E/e' ratio to assess LV diastolic function and late gadolinium enhancement to evaluate the extent of fibrosis. Data were assorted according to LVOT obstruction status at rest. RESULTS: The current study enrolled 67 patients who were mostly middle-aged (56.8 ±â€Š13.2 years old) men (75%) with preserved ejection fraction. Obstructive HCM presented a significant association with a high fibrosis extent [odds ratio (OR) 3.33; P = 0.034] which was maintained after adjusting for sex and age (OR 4.37; P = 0.016) but not for maximum LV wall thickness (OR 2.13; P = 0.225). Obstructive HCM was also associated with a clinically significant E/e' ratio more than 14 (OR 7.8; P = 0.001) which decreased slightly after adjusting for age, sex and maximum LV thickness (OR 6.54; P = 0.014). There was a significant association between an E/e' ratio more than 14 and the extent of fibrosis (OR 1.29; P < 0.001) which was maintained after adjusting for age, sex and maximum LV wall thickness (OR 1.36; P = 0.001). CONCLUSION: LVOT obstruction may play a role in the extent of fibrosis in HCM, possibly conditioning greater diastolic dysfunction.


Assuntos
Cardiomiopatia Hipertrófica/diagnóstico por imagem , Ecocardiografia Doppler , Imagem Cinética por Ressonância Magnética , Miocárdio/patologia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Função Ventricular Esquerda , Obstrução do Fluxo Ventricular Externo/diagnóstico por imagem , Remodelação Ventricular , Adulto , Idoso , Cardiomiopatia Hipertrófica/patologia , Cardiomiopatia Hipertrófica/fisiopatologia , Estudos Transversais , Feminino , Fibrose , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Volume Sistólico , Fatores de Tempo , Disfunção Ventricular Esquerda/patologia , Disfunção Ventricular Esquerda/fisiopatologia , Obstrução do Fluxo Ventricular Externo/patologia , Obstrução do Fluxo Ventricular Externo/fisiopatologia , Pressão Ventricular
15.
Int J Cardiovasc Imaging ; 35(6): 1089-1100, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30825136

RESUMO

Surgical therapies in aortic valve stenosis (AVS) and hypertrophic obstructive cardiomyopathy (HOCM) aim to relief intraventricular pressure overload and improve clinical outcome. It is currently unknown to what extent myocardial adaptation concurs with restoration of intraventricular pressures, and whether this is similar in both patient groups. The aim of this study was to investigate changes in myocardial adaptation after surgical therapies for AVS and HOCM. Ten AVS and ten HOCM patients were enrolled and underwent cardiac magnetic resonance cine imaging and myocardial tagging prior to, and 4 months after aortic valve replacement (AVR) and septal myectomy, respectively. Global left ventricular (LV) analyses were derived from cine images. Circumferential strain was assessed from myocardial tagging images at the septal and lateral wall of the mid ventricle. Pressure gradients significantly decreased in both AVS and HOCM after surgery (p < 0.01), with a concomitant decrease in left atrial volume (p < 0.05) suggesting lower diastolic filling pressures. Also, LV volumes, mass and septal wall thickness decreased in both, but to a larger extent in AVS than in HOCM patients. AVR improved wall thickening (p < 0.05) and did not change systolic strain rate. Myectomy did not affect wall thickening and reduced septal systolic strain rate (p = 0.03). Both AVR and myectomy induced positive structural remodeling in line with a reduction of pressure overload. A concomitant recovery in systolic function however was found in AVR only. The systolic functional deterioration in HOCM patients seems to be inherent to myectomy and the ongoing and irreversible disease.


Assuntos
Estenose da Valva Aórtica/cirurgia , Cardiomiopatia Hipertrófica/cirurgia , Implante de Prótese de Valva Cardíaca , Função Ventricular Esquerda , Pressão Ventricular , Remodelação Ventricular , Adaptação Fisiológica , Adulto , Idoso , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/fisiopatologia , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Cardiomiopatia Hipertrófica/fisiopatologia , Feminino , Humanos , Imagem Cinética por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recuperação de Função Fisiológica , Sístole , Fatores de Tempo , Resultado do Tratamento
16.
Am J Cardiol ; 123(9): 1464-1469, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30819432

RESUMO

Although several tissue-Doppler imaging (TDI) models for pulmonary capillary wedge pressure (PCWP) estimation have been reported, their reliability remains uncertain. Our previous theoretical and experimental analyses suggest that right atrial pressure (RAP) corrected by tissue-Doppler imaging tricuspid/mitral annular peak systolic velocities (ST/SM) (RAP × ST/SM) reliably predicts elevated PCWP. We sought to investigate its clinical usefulness for predicting elevated PCWP in heart failure (HF) patients. Ninety-eight patients admitted with HF who underwent right heart catheterization were prospectively studied. RAP and PCWP were measured by right heart catheterization. Simultaneously, ST/SM, early diastolic transmitral flow velocity to mitral annular velocity ratio (E/Ea), and diameter of inferior vena cava at inspiration (IVCDi), a noninvasive surrogate for RAP, were measured by echocardiography. RAP correlated with IVCDi (R2 = 0.57). A significantly stronger correlation was observed between IVCDi corrected by ST/SM (IVCDi × ST/SM) and PCWP than between E/Ea and PCWP (R2 = 0.47 vs 0.18). Receiver-operating characteristic analyses indicated that IVCDi × ST/SM >16 mm predicted PCWP >18 mm Hg with 90% sensitivity and 77% specificity, and the area under the curve was 0.86, which was significantly larger than that of E/Ea (area under the curve=0.72). In conclusions, IVCDi × ST/SM is a new useful noninvasive model to predict elevated PCWP in HF patients.


Assuntos
Ecocardiografia Doppler/métodos , Insuficiência Cardíaca/diagnóstico , Pressão Propulsora Pulmonar/fisiologia , Função Ventricular Direita/fisiologia , Pressão Ventricular/fisiologia , Feminino , Seguimentos , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Curva ROC , Reprodutibilidade dos Testes , Volume Sistólico/fisiologia
17.
Cells ; 8(2)2019 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-30813473

RESUMO

Aquaporin 1 (AQP1), expressed in epithelial cells of the choroid plexus, and aquaporin 4 (AQP4) present in ependymal cells and glia limitants have been proposed to play a significant role in cerebrospinal fluid (CSF) production and homeostasis. However, the specific contribution of each water channel to these functions remains unknown, being a subject of debate during the last years. Here, we analyzed in detail how AQP1 and AQP4 participate in different aspects of the CSF homeostasis such as the load and drainage of ventricles, and further explored if these proteins play a role in the ventricular compliance. To do that, we carried out records of intraventricular pressure and CSF outflow, and evaluated ventricular volume by magnetic resonance imaging in AQP1-/-, AQP4-/-, double AQP1-/--AQP4-/- knock out and wild type mice controls. The analysis performed clearly showed that both AQPs have a significant participation in the CSF production, and additionally revealed that the double AQP1-AQP4 mutation alters the CSF drainage and the ventricular compliance. The data reported here indicate a significant extra-choroidal CSF formation mediated by AQP4, supporting the idea of an important and constant CSF production/absorption process, sustained by efflux/influx of water between brain capillaries and interstitial fluid. Moreover, our results suggest the participation of AQPs in structural functions also related with CSF homeostasis such as the distensibility capacity of the ventricular system.


Assuntos
Aquaporina 1/líquido cefalorraquidiano , Aquaporina 4/líquido cefalorraquidiano , Homeostase , Animais , Imagem por Ressonância Magnética , Masculino , Camundongos Knockout , Pressão Ventricular
18.
Int J Cardiol ; 281: 62-68, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30718133

RESUMO

AIMS: The current algorithm in transthoracic echocardiography (TTE) proposed in the 2016 ASE/EACVI recommendation for the estimation of left ventricular filling pressure (LVFP) is quite complex and time-consuming. B-lines, in lung ultrasonography (LUS), could constitute an interesting tool for LVFP evaluation in clinical practice, although data regarding their association with invasive haemodynamics are lacking. The purpose of this study was to explore the diagnostic accuracy of B-lines in identifying elevated left ventricular end-diastolic pressure (LVEDP). METHOD AND RESULTS: 81 adults with significant dyspnoea (NYHA ≥ 2) were prospectively analyzed by LUS in four areas in each hemithorax and a complete TTE within four hours prior to coronary angiography. Twenty-eight patients had elevated LVEDP. Clinical variables yielded a C-index of 79% to identify elevated LVEDP. The number of total B-lines was higher in the elevated LVEDP group (1.0vs17.0, p < 0.0001) and significantly increased the diagnostic accuracy (C-index increase = 10.5%, p = 0.002) and net reclassification index (NRI = 145.4, 113.0-177.9, p < 0.0001) on top of clinical variables. CONCLUSION: This study demonstrates the substantial diagnostic capacity of B-lines to identify elevated LVEDP, which appears superior to that of classical echocardiographic strategies. This tool should be considered in a multi-parametric approach in patients with heart failure.


Assuntos
Pulmão/diagnóstico por imagem , Ultrassonografia de Intervenção/normas , Função Ventricular Esquerda/fisiologia , Pressão Ventricular/fisiologia , Idoso , Idoso de 80 Anos ou mais , Dispneia/diagnóstico por imagem , Dispneia/fisiopatologia , Feminino , Humanos , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
19.
Clin Res Cardiol ; 108(8): 931-939, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30737530

RESUMO

BACKGROUND: Controversy exists about the pathophysiology of different hemodynamic subgroups of AS. In particular, the mechanism of the paradoxical low-flow, low-gradient (PLFLG) AS with preserved ejection fraction (EF) is unclear. METHODS: A total of 41 patients with severe, symptomatic AS were divided into the following 4 subgroups based on the echocardiographically determined hemodynamics: (1) normal-flow, high-gradient (NFHG) AS; (2) low-flow, high-gradient AS; (3) paradoxical low-flow, low-gradient (PLFLG) AS with preserved EF and (4) low-flow, low-gradient (LFLG) AS with reduced EF. As part of the comprehensive invasive examinations, the analyses of the PV loops were performed with the IntraCardiac Analyzer (CD-Leycom, The Netherlands). RESULTS: PLFLG was characterized by small left ventricular volumes as well as a decreased cardiac index, a decreased systolic contractility and a lower stroke work, than the conventional NFHG AS. Alterations in effective arterial elastance (2.36 ± 0.67 mmHg/ml in NFHG versus 3.01 ± 0.79 mmHg/ml in PLFLG, p = 0.036) and end-systolic elastance (3.72 ± 1.84 mmHg/ml in NFHG versus 5.53 ± 2.3 mmHg/ml in PLFLG, p = 0.040) indicated impaired vascular function and increased chamber stiffness. CONCLUSIONS: The present study suggests that the hemodynamics of PLFLG AS can be explained by two mechanisms: (1) stiffness of the small left ventricle with reduced contractility, and (2) increased afterload due to the impairment of vascular function. Both mechanisms have similarities to those of heart failure with preserved EF. This type of remodeling may explain the poor prognosis of PLFLG AS.


Assuntos
Estenose da Valva Aórtica/fisiopatologia , Valva Aórtica/diagnóstico por imagem , Cateterismo Cardíaco/métodos , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia , Pressão Ventricular/fisiologia , Idoso , Idoso de 80 Anos ou mais , Estenose da Valva Aórtica/diagnóstico , Ecocardiografia , Feminino , Seguimentos , Hemodinâmica/fisiologia , Humanos , Masculino , Estudos Prospectivos , Índice de Gravidade de Doença
20.
Congenit Heart Dis ; 14(1): 42-45, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30811799

RESUMO

Management of the patent ductus arteriosus (PDA) in the premature infant has been a point of controversy for decades as smaller and earlier gestational age infants have been surviving. Increasing experience with catheter-based device closure has generated a new wave of interest in this subject. In this era, echocardiography plays a central role for collaboration within a multispecialty team. Reliability of echocardiography is improved by applying an institutionally derived standard approach to imaging, data collection, and reporting. The key aspects of both the physiology and anatomy of the PDA to distinguish infants that may benefit from intervention are described.


Assuntos
Permeabilidade do Canal Arterial/diagnóstico , Canal Arterial/diagnóstico por imagem , Ecocardiografia/métodos , Recém-Nascido Prematuro , Pressão Ventricular/fisiologia , Velocidade do Fluxo Sanguíneo/fisiologia , Cateterismo Cardíaco/métodos , Canal Arterial/fisiopatologia , Permeabilidade do Canal Arterial/fisiopatologia , Idade Gestacional , Humanos , Recém-Nascido , Reprodutibilidade dos Testes
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