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1.
J Vis Exp ; (167)2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33491675

RESUMO

Magnetic resonance imaging (MRI) is an important tool for the clinical assessment of cardiovascular morphology and heart function. It is also the recognized standard-of-care for blood flow quantification based on phase contrast MRI. While such measurement of blood flow has been possible in adults for decades, methods to extend this capability to fetal blood flow have only recently been developed. Fetal blood flow quantification in major vessels is important for monitoring fetal pathologies such as congenital heart disease (CHD) and fetal growth restriction (FGR). CHD causes alterations in the cardiac structure and vasculature that change the course of blood in the fetus. In FGR, the path of blood flow is altered through the dilation of shunts such that the oxygenated blood supply to the brain is increased. Blood flow quantification enables assessment of the severity of the fetal pathology, which in turn allows for suitable in utero patient management and planning for postnatal care. The primary challenges of applying phase contrast MRI to the human fetus include small blood vessel size, high fetal heart rate, potential MRI data corruption due to maternal respiration, unpredictable fetal movements, and lack of conventional cardiac gating methods to synchronize data acquisition. Here, we describe recent technical developments from our lab that have enabled the quantification of fetal blood flow using phase contrast MRI, including advances in accelerated imaging, motion compensation, and cardiac gating.


Assuntos
Circulação Sanguínea/fisiologia , Sangue Fetal/fisiologia , Imagem por Ressonância Magnética , Movimento (Física) , Adulto , Aorta/fisiologia , Feminino , Feto/fisiologia , Frequência Cardíaca Fetal/fisiologia , Hemodinâmica , Humanos , Gravidez , Reprodutibilidade dos Testes , Sístole/fisiologia
2.
Medicine (Baltimore) ; 99(45): e22881, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33157931

RESUMO

The number of femoral fractures is expected to continue to increase as the size of the older population rapidly grows. However, old age is accompanied by various comorbidities and is an important postoperative risk factor in itself, meaning that patients who undergo surgery for a femur fracture may require admission to an ICU. We investigated pulmonary complications in patients over the age of 65 admitted to the ICU after femur fracture surgery.In this single-center retrospective observational study, 289 patients over 65 years who admitted to the ICU after femur fracture surgery between June 2008 and December 2016 were investigated.Pulmonary complications occurred in 97 of these patients (33.6%) after surgery. Mean hospitalization days (34.1 ±â€Š25.7 vs 23.1 ±â€Š15.7, P < .001) and mean ICU length of stay (8.4 ±â€Š16.1 vs 2.5 ±â€Š1.1, P = .001) were significantly longer for patients with pulmonary complications than for patients without pulmonary complications after femur fracture surgery. Patients with pulmonary complications were significantly more likely to have pulmonary disease (19.6% vs 8.9%, P = .009) and exhibit sequelae on preoperative chest X-rays (9.3% vs 3.6%, P = .048) than were patients without pulmonary complications. In addition, significant differences were observed in the right ventricular systolic pressure (RVSP) measured during preoperative echocardiography (37.4 ±â€Š10.9 mm Hg vs 40.7 ±â€Š9.3 mm Hg for patients without and with pulmonary complications, P = .010) and in the proportion of each group that had an RVSP of >35 mm Hg, which is a marker for pulmonary hypertension (55.2% vs 76.3% for patients without and with pulmonary complications, P < .001). In multivariate analysis, an RVSP of >35 mm Hg during preoperative echocardiography was associated with pulmonary complications after femur fracture surgery (OR, 2.6; 95% CI, 1.45-4.53).In conclusion, Pulmonary complications in older patients admitted to the ICU after femur fracture surgery was associated with longer hospitalization and ICU stays. Preoperative RVSP measurement could identify those older patients with a high risk of pulmonary complications following transferal to the ICU after femur fracture surgery.


Assuntos
Pressão Sanguínea/fisiologia , Fraturas do Fêmur/cirurgia , Unidades de Terapia Intensiva , Doenças Respiratórias/epidemiologia , Sístole/fisiologia , Função Ventricular Direita/fisiologia , Idoso , Idoso de 80 Anos ou mais , Ecocardiografia , Feminino , Humanos , Tempo de Internação , Masculino , Admissão do Paciente , Complicações Pós-Operatórias , Cuidados Pré-Operatórios , República da Coreia/epidemiologia , Estudos Retrospectivos
3.
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
4.
PLoS One ; 15(8): e0238039, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32853284

RESUMO

Sepsis is a global economic and health burden. Dipeptidyl peptidase 3 (DPP3) is elevated in the plasma of septic patients. The highest levels of circulating DPP3 (cDPP3) are found in non-survivor septic shock patients. The aim of this study was to evaluate the benefits of inhibiting cDPP3 by a specific antibody, Procizumab (PCZ), on cardiac function in an experimental model of sepsis, the caecal ligature and puncture (CLP) model. Rats were monitored by invasive blood pressure and echocardiography. Results are presented as mean ± SD, with p <0.05 considered significant. PCZ rapidly restored left ventricular shortening fraction (from 39 ± 4% to 51 ± 2% before and 30 min after PCZ administration (p = 0.004)). Cardiac output and stroke volume were higher in the CLP + PCZ group when compared to the CLP + PBS group (152 ± 33 mL/min vs 97 ± 25 mL/min (p = 0.0079), and 0.5 ± 0.1 mL vs 0.3 ± 1.0 mL (p = 0.009), respectively) with a markedly reduced plasma DPP3 activity (138 ± 70 U/L in CLP + PCZ group versus 735 ± 255 U/L (p = 0.048) in the CLP + PBS group). Of note, PCZ rapidly reduced oxidative stress in the heart of the CLP + PCZ group when compared to those of the CLP + PBS group (13.3 ± 8.2 vs 6.2 ± 2.5 UI, p = 0.005, 120 min after administration, respectively). Our study demonstrates that inhibition of cDPP3 by PCZ restored altered cardiac function during sepsis in rats.


Assuntos
Dipeptidil Peptidases e Tripeptidil Peptidases/antagonistas & inibidores , Dipeptidil Peptidases e Tripeptidil Peptidases/sangue , Inibidores Enzimáticos/farmacologia , Coração/efeitos dos fármacos , Coração/fisiopatologia , Sepse/sangue , Sepse/fisiopatologia , Animais , Modelos Animais de Doenças , Hemodinâmica/efeitos dos fármacos , Masculino , Estudo de Prova de Conceito , Ratos , Ratos Wistar , Sepse/enzimologia , Sístole/efeitos dos fármacos , Sístole/fisiologia
5.
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
6.
Surg Clin North Am ; 100(4): 807-822, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32681878

RESUMO

Peripheral arterial disease (PAD) affects many individuals worldwide and is associated with increased morbidity and mortality. Controversy exists on whether or not to screen asymptomatic patients. Further complicating this is that many patients with a chronic lower extremity wound are often asymptomatic. PAD and traditional noninvasive vascular studies may be inaccurate in providing a correct diagnosis. A review of current and novel vascular assessment modalities along with their benefits and limitations are presented here. A combination of these vascular assessments may help improve accuracy in diagnosis, providing timely care to those patients in need.


Assuntos
Perna (Membro)/irrigação sanguínea , Doença Arterial Periférica/fisiopatologia , Índice Tornozelo-Braço , Monitorização Transcutânea dos Gases Sanguíneos/métodos , Pressão Sanguínea/fisiologia , Determinação da Pressão Arterial/métodos , Humanos , Pele/irrigação sanguínea , Dermatopatias Vasculares/fisiopatologia , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Sístole/fisiologia , Cicatrização/fisiologia
7.
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
8.
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
9.
J Ayub Med Coll Abbottabad ; 32(2): 169-173, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32583988

RESUMO

BACKGROUND: In rheumatic severe mitral regurgitation, earlier detection of left ventricular dysfunction is very necessary in order to refer the patients for surgery at appropriate time. This study tried to find a correlation between conventional parameters of left ventricular dysfunction with systolic strain rate. METHODS: A descriptive correlational study conducted from September 2016 to March 2018. One hundred and ninety-two patients of severe rheumatic MR and fifty-eight healthy controls were included. Left ventricular ejection fraction (LVEF), end diastolic dimension (LVEDD) and end systolic dimension (LVESD) were measured. Healthy controls were taken as group-I and patients were divided into group-II (ejection fraction ≥60% and LVESD ≤40 mm), group-III (ejection fraction ≥60% and LVESD ≤41-50 mm), and group-IV (ejection fraction <60%). Systolic strain rate at medial wall (SSR-med), at lateral wall (SSR-lat) and average of both (SSR-avg) were also measured by tissue doppler method for each study subject. RESULTS: Out of 250 study subjects, males were 113 (45.2%) and females were 137 (54.8%). Means of the age, LVEF, LVEDD and LVESD were 30.8±9.1, 60.0±8.3, 58.5±7.8 and 37.4±9.9 respectively. Group I, II, III and IV contained 58, 69, 67 and 56 subjects respectively. Comparing these groups, mean LVEF progressively decreased from 63.9%±2.2 in group-I to 46.2±6.5 in group-IV while means of LVEDD and LVESD progressively increased from 45.9±3.5 and 23.2±2.3 in group-I to 64.3±3.6 and 49.0±2.9 in group-IV respectively. Average systolic strain rate (SSR-avg) decreased progressively from 1.57±0.06 in group-I to 0.83±0.08 in group-IV. All the strain rates, i.e., SSRmed, SSR-lat and SSR-avg showed significant negative correlation with left ventricular dysfunction, i.e., the group number (p<0.001). CONCLUSIONS: Systolic strain rate measured by tissue doppler method have significant negative correlation with left ventricular dysfunction in patients having rheumatic chronic severe mitral regurgitation.


Assuntos
Insuficiência da Valva Mitral , Sístole/fisiologia , Disfunção Ventricular Esquerda , Doença Crônica , Humanos , Insuficiência da Valva Mitral/complicações , Insuficiência da Valva Mitral/epidemiologia , Insuficiência da Valva Mitral/fisiopatologia , Disfunção Ventricular Esquerda/epidemiologia , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/fisiopatologia
10.
Am Heart J ; 225: 78-87, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32474207

RESUMO

BACKGROUND: The severity of aortic coarctation (CoA) may be underestimated during cardiac catheterization. We aimed to investigate whether epinephrine stress testing improves clinical decision making and outcome in CoA. METHODS: We retrospectively evaluated CoA patients >50 kg with a peak systolic gradient (PSG) ≤20 mm Hg during cardiac catheterization who underwent epinephrine stress testing. Subsequent interventional management (stenting or balloon dilatation), complications, and medium-term clinical outcome were assessed. RESULTS: Fifty CoA patients underwent cardiac catheterization with epinephrine stress testing. Patients with a high epinephrine PSG (>20 mm Hg; n = 24) were younger and more likely to have a hypertensive response to exercise compared to patients with a low epinephrine PSG (≤20 mm Hg; n = 26). In total, 21 patients (88%) with a high epinephrine PSG underwent intervention, and 20 patients (77%) with a low epinephrine PSG were treated conservatively. After a mean follow-up of 25 ±â€¯18 months, there was a lower prevalence of hypertension in patients with a high epinephrine PSG who underwent intervention compared to patients with a low epinephrine PSG treated conservatively (19% vs. 76%; P = .001). In a multivariate model, intervention was independently associated with a 14.3-mm Hg reduction in systolic blood pressure (P = .001) and a decrease in the use of antihypertensive agents. CONCLUSIONS: In CoA patients with a low baseline PSG but high epinephrine PSG, percutaneous intervention is associated with a substantial reduction in systemic blood pressure and the use of antihypertensive medication. Accordingly, epinephrine stress testing may be a useful addition in the evaluation of CoA.


Assuntos
Agonistas Adrenérgicos beta/farmacologia , Coartação Aórtica/cirurgia , Pressão Sanguínea/efeitos dos fármacos , Cateterismo Cardíaco , Epinefrina/farmacologia , Adolescente , Adulto , Coartação Aórtica/diagnóstico , Coartação Aórtica/fisiopatologia , Tomada de Decisão Clínica , Teste de Esforço/métodos , Feminino , Humanos , Hipertensão/etiologia , Masculino , Estudos Retrospectivos , Sístole/fisiologia , Adulto Jovem
11.
Sci Rep ; 10(1): 6608, 2020 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-32313023

RESUMO

Tobacco smoking is a well-established risk factor for cardiovascular disease, but its direct effect on myocardial structure and function remains unclear. This study investigated the effects of smoking using a nested matched case-control study design. 5,668 participants of the UK Biobank study who underwent cardiovascular magnetic resonance imaging were screened for inclusion. 102 smokers (56 males) with a median age of 56 years were matched to non-smokers based on sex, age, and body surface area. Manual post-processing and feature tracking analyses were performed to determine left ventricular (LV) and right ventricular (RV) structure and function measures. Linear regression analyses were performed to determine the effect of tobacco smoking on imaging measures. Tobacco smoking was associated with increased LV and RV end-systolic volume (4.98 ± 2.08 mL, 5.19 ± 2.62 mL, P = 0.018, 0.049 respectively), reduced LV and RV ejection fraction (ß: -2.21 ± 0.82%, -2.06 ± 0.87%, P = 0.007, 0.019 respectively), and reduced absolute measures of LV peak global longitudinal, radial, and circumferential strain (ß: 0.86 ± 0.30%, -2.52 ± 0.99%, 1.05 ± 0.32%, P = 0.004, 0.011, 0.001 respectively). Effect sizes were larger in daily smokers compared to occasional smokers. In a general Caucasian population without known clinical cardiovascular disease, active tobacco smoking was dose dependently associated with impaired cardiac systolic function.


Assuntos
Coração/fisiopatologia , Sístole/fisiologia , Fumar Tabaco/fisiopatologia , Feminino , Testes de Função Cardíaca , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Volume Sistólico
12.
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
13.
Arch Dis Child ; 105(6): 533-538, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32094247

RESUMO

OBJECTIVE: To evaluate if qualitative visual detection of pulsus paradoxus (PP) on the pulse oximeter plethysmograph can predict outcomes for children with moderate to severe respiratory distress in a paediatric emergency department (ED). DESIGN: Prospective cohort study. SETTING: Paediatric ED of a tertiary paediatrics hospital in Singapore. PATIENTS: Children managed for moderate to severe wheezing in the resuscitation bay of the ED. INTERVENTIONS: Patients were assessed for the presence of PP based on visual detection of oximeter plethysmograph before and after initial inhaled bronchodilator therapy. MAIN OUTCOME MEASURES: These include the need for adjunct medications such as aminophylline or magnesium sulfate, the need for supplementary ventilation and the need for admission to the high dependency unit (HDU) or intensive care unit (ICU). RESULTS: There were 285 patients included in the study, of whom 78 (27.4%) had PP at ED presentation. There were 40 (14.0%) who had PP after initial management. Children who had PP after initial management had significantly relative risks (RR) of requiring adjunct medications (RR 12.5, 95% CI 4.0 to 38.6), need for supplementary ventilation (RR 5.6, 95% CI 1.2 to 26.5) and admission to the HDU/ICU (RR 5.6, 95% CI 3.0 to 10.4). CONCLUSION: Qualitative detection of PP on pulse oximetry can be used as a potential point-of-care tool to help in the assessment of response to initial treatment in paediatric patients with acute moderate to severe asthma exacerbations. Future studies are needed to assess and validate its role in guiding ED management of acute paediatric asthma.


Assuntos
Asma/fisiopatologia , Pressão Sanguínea/fisiologia , Oximetria , Pletismografia , Índice de Gravidade de Doença , Adolescente , Aminofilina/uso terapêutico , Antiasmáticos/uso terapêutico , Asma/terapia , Broncodilatadores/uso terapêutico , Criança , Pré-Escolar , Estudos de Coortes , Serviço Hospitalar de Emergência , Feminino , Humanos , Lactente , Recém-Nascido , Unidades de Terapia Intensiva , Sulfato de Magnésio/uso terapêutico , Masculino , Oxigenoterapia , Admissão do Paciente , Sons Respiratórios/fisiopatologia , Sístole/fisiologia
14.
Sci Rep ; 10(1): 3342, 2020 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-32094479

RESUMO

Rapid eye movement-predominant obstructive sleep apnea has been shown to be independently associated with hypertension. This study aimed to non-invasively measure blood pressure during the rapid eye movement (REM) and non-rapid eye movement (NREM) obstructive events and the post-obstructive event period. Thirty-two consecutive continuous positive airway pressure-naïve obstructive sleep apnea patients (men, 50%) aged 50.2 ± 12 years underwent overnight polysomnography. Blood pressure was assessed indirectly using a validated method based on the pulse transit time and pulse wave velocity during the NREM and REM obstructive events (both apneas and hypopneas) and the post-obstructive event period. Among the recruited patients, 10 (31.3%) had hypertension. Mean apnea-hypopnea index was 40.1 ± 27.6 events/hr. Apnea-hypopnea indexes were 38.3 ± 30.6 and 51.9 ± 28.3 events/hr for NREM and REM sleep, respectively. No differences were detected in obstructive respiratory event duration or degree of desaturation between REM and NREM sleep. Additionally, no difference in blood pressure (systolic and diastolic) was detected between REM and NREM sleep during obstructive events and post-obstructive event period. Simple linear regression identified history of hypertension as a predictor of increased systolic blood pressure during obstructive events and post-obstructive event period in both rapid eye movement and non-rapid eye movement sleep. Oxygen desaturation index was also a predictor of increased systolic blood pressure during obstructive events and post-obstructive event period in REM sleep. When obstructive event duration and the degree of desaturation were comparable, no difference in blood pressure was found between REM and NREM sleep during obstructive events and post-obstructive event period.


Assuntos
Pressão Sanguínea/fisiologia , Análise de Onda de Pulso , Respiração , Apneia Obstrutiva do Sono/fisiopatologia , Sono REM/fisiologia , Feminino , Humanos , Hipertensão/fisiopatologia , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Polissonografia , Sono de Ondas Lentas , Sístole/fisiologia
15.
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
16.
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
17.
Comput Methods Biomech Biomed Engin ; 23(1): 33-42, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31805773

RESUMO

This study numerically investigated the hemodynamics of a patient-specific coronary artery fistula (CAF) before and after the fistula closure. The results indicated that the dilated fistula result in inadequate perfusion to other healthy aortas. Disturbed blood flow, aberrant WSSs, local negative pressure gradients and sharp pressure changes are shown in both untreated and occluded fistula. Furthermore, extreme high WSS appeared at the fistula bending after the terminal closure. It was concluded that the fistula closure may effectively improve the phenomenon of stealing blood but worsen the unfavorable hemodyanmics predisposing the thrombosis formation due to its geometrical torturosity.


Assuntos
Vasos Coronários/fisiopatologia , Fístula/fisiopatologia , Hidrodinâmica , Adulto , Doença da Artéria Coronariana/fisiopatologia , Diástole/fisiologia , Hemorreologia , Humanos , Imageamento Tridimensional , Masculino , Modelos Cardiovasculares , Pressão , Estresse Mecânico , Sístole/fisiologia
18.
Int J Cardiol ; 300: 172-177, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31787386

RESUMO

BACKGROUND: Systolic function recovery in patients with Heart failure (HF) with reduced ejection fraction (EF) is well recognized but not completely understood. We aimed to characterize HF patients with systolic function recovery, its prognostic impact and predictors. METHODS: We analysed patients followed in a HF clinic (2006-2015) with 2 echocardiograms performed. Partial recovery: EF recovery without attaining EF ≥ 50%; total recovery: patients reached EF ≥ 50%. Median follow-up from first echocardiogram: 69 months. Multivariate logistic regression models to determine recovery predictors. RESULTS: We analysed 304 patients with at least mild left ventricular dysfunction. During a median 34 months between echocardiogram re-evaluation 150 (49.3%) patients showed no EF recovery; 55 (18.1%) had partial recovery and 99 (32.6%) totally recovered. Mean patients age: 66; 71.1% men, high comorbidity burden; ischemic HF: 35.5%. Non-recovered patients were mostly men (80.7% vs 61.8% in partially; 61.6% in fully-recovered) with ischemic HF (46.0% vs 32.5% in partially; 21.2% in fully-recovered). Comorbidity burden, NYHA class and therapy were similar. During follow-up, 156 patients (46.7%) died. Patients with total recovery had a multivariate-adjusted 54% lower risk of dying when compared to non-recovered. Partially-recovered patients showed a non-significant adjusted 8% mortality reduction. Independent predictors of systolic function recovery were female gender(OR: 2.17, 95% CI 1.11-4.35), non-ischemic aetiology (OR: 2.78, 95% CI 1.35-5.56), and end diastolic left ventricular diameter < 60 mm (OR: 3.12, 95% CI 1.56-6.25). CONCLUSIONS: HF-recovered patients were mainly women with non-ischemic HF and smaller left ventricles. These patients had significantly better prognosis than those with persistently reduced EF.


Assuntos
Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Recuperação de Função Fisiológica/fisiologia , Sístole/fisiologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Ecocardiografia/métodos , Ecocardiografia/tendências , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos
19.
Int J Numer Method Biomed Eng ; 36(1): e3291, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31799767

RESUMO

Myocardial infarct extension, a process involving the enlargement of infarct and border zone, leads to progressive degeneration of left ventricular (LV) function and eventually gives rise to heart failure. Despite carrying a high risk, the causation of infarct extension is still a subject of much speculation. In this study, patient-specific LV models were developed to investigate the correlation between infarct extension and impaired regional mechanics. Subsequently, sensitivity analysis was performed to examine the causal factors responsible for the impaired regional mechanics observed in regions surrounding the infarct and border zone. From our simulations, fibre strain, fibre stress and fibre stress-strain loop (FSSL) were the key biomechanical variables affected in these regions. Among these variables, only FSSL was correlated with infarct extension, as reflected in its work density dissipation (WDD) index value, with high WDD indices recorded at regions with infarct extension. Impaired FSSL is caused by inadequate contraction force generation during the isovolumic contraction and ejection phases. Our further analysis revealed that the inadequacy in contraction force generation is not necessarily due to impaired myocardial intrinsic contractility, but at least in part, due to inadequate muscle fibre stretch at end-diastole, which depresses the ability of myocardium to generate adequate contraction force in the subsequent systole (according to the Frank-Starling law). Moreover, an excessively stiff infarct may cause its neighbouring myocardium to be understretched at end-diastole, subsequently depressing the systolic contractile force of the neighbouring myocardium, which was found to be correlated with infarct extension.


Assuntos
Diástole/fisiologia , Infarto do Miocárdio/fisiopatologia , Miocárdio/patologia , Adulto , Idoso , Simulação por Computador , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Cardiovasculares , Sarcômeros/fisiologia , Estresse Mecânico , Sístole/fisiologia
20.
J Biomech ; 98: 109428, 2020 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-31653505

RESUMO

Although cardiac wall mechanics is of importance for understanding heart failure with preserved ejection fraction (HFpEF), there is a lack of relevant mechanics studies. The aim of this study was to analyze the changes in stress and strain in the left ventricle (LV) in hypertension-induced HFpEF rats. Based on experimental measurements in DSS rats fed with high-salt (HS) and low-salt (LS) diets, LV stress and strain were computed throughout the cardiac cycle using Continuity software. HS-feeding increased myofiber stress and strain along both the transmural and longitudinal directions at the end-diastolic state but resulted in a lower absolute value of strain and relatively unchanged stress at the end-systolic state. Moreover, the end-diastolic stress and strain decreased with increasing radial position from the endocardial towards the epicardial walls despite negligible changes along the longitudinal direction. The changes in LV wall mechanics characterized the elevated diastolic LV stiffness and slow LV relaxation in HS-fed rats of HFpEF. These findings denote that a vicious cycle of increased stress and strain and diastolic dysfunction can prompt the development of HFpEF.


Assuntos
Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/fisiopatologia , Hipertensão/complicações , Estresse Mecânico , Volume Sistólico , Animais , Fenômenos Biomecânicos , Diástole/fisiologia , Feminino , Coração , Humanos , Masculino , Ratos , Sístole/fisiologia
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