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1.
Nat Protoc ; 16(7): 3241-3263, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34075229

RESUMO

Measurements of neuronal activity across brain areas are important for understanding the neural correlates of cognitive and motor processes such as attention, decision-making and action selection. However, techniques that allow cellular resolution measurements are expensive and require a high degree of technical expertise, which limits their broad use. Wide-field imaging of genetically encoded indicators is a high-throughput, cost-effective and flexible approach to measure activity of specific cell populations with high temporal resolution and a cortex-wide field of view. Here we outline our protocol for assembling a wide-field macroscope setup, performing surgery to prepare the intact skull and imaging neural activity chronically in behaving, transgenic mice. Further, we highlight a processing pipeline that leverages novel, cloud-based methods to analyze large-scale imaging datasets. The protocol targets laboratories that are seeking to build macroscopes, optimize surgical procedures for long-term chronic imaging and/or analyze cortex-wide neuronal recordings. The entire protocol, including steps for assembly and calibration of the macroscope, surgical preparation, imaging and data analysis, requires a total of 8 h. It is designed to be accessible to laboratories with limited expertise in imaging methods or interest in high-throughput imaging during behavior.


Assuntos
Comportamento Animal/fisiologia , Córtex Cerebral/citologia , Córtex Cerebral/diagnóstico por imagem , Imageamento Tridimensional/métodos , Animais , Artefatos , Hemodinâmica/fisiologia , Camundongos Transgênicos , Crânio/cirurgia
2.
Afr J Reprod Health ; 25(1): 81-89, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34077114

RESUMO

Maternal position is one of the most important factors to be considered during Non-Stress Test (NST). It should be a part of practice guidelines, where the appropriate maternal position reduces test-related errors and false-positive results. This study aimed to investigate the effect of different maternal positions during NST on maternal hemodynamic parameters, satisfaction, and fetal Cardiotocographic (CTG) pattern. A quasi-experimental research design was conducted at NST clinic, outpatient department/ Maternal and Children hospital at Najran city, Saudi Arabia. The study comprised a convenience sample of 118 low-risk pregnant women in their third trimester of pregnancy. Data was collected from January to June 2020. All women were assessed in the three different positions; supine, left lateral, and semi-fowler position concerning CTG pattern, maternal hemodynamic parameters, and satisfaction. The study results indicated a higher Fetal Heart Rate (FHR), increased accelerations, and fetal movement in the left lateral position, followed by a semi-fowler position compared to the supine position with statistically significant differences. No statistically significant differences (P>0.05) were observed regarding FHR variability and NST reactivity in the three positions. In addition, there were statistically significant differences (P <0.05) between the different maternal positions regarding maternal heart rate, systolic Blood pressure (BP), diastolic BP, and maternal satisfaction. The current study concluded that left lateral and semi- fowler positions were associated with a more favorable CTG pattern, maternal hemodynamic parameters, and satisfaction than the supine position. Left lateral and semi-fowler positions during the NST test should be standardized to reduce practical variations among health care providers, which, in turn, may reduce the need for unnecessary, expensive, and even hazardous interventions.


Assuntos
Cardiotocografia/métodos , Monitorização Fetal/métodos , Frequência Cardíaca Fetal/fisiologia , Satisfação Pessoal , Postura/fisiologia , Adulto , Feminino , Coração Fetal/fisiologia , Movimento Fetal/fisiologia , Hemodinâmica/fisiologia , Humanos , Gravidez , Gestantes , Cuidado Pré-Natal
3.
Int Heart J ; 62(3): 710-714, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34054004

RESUMO

We present the case of a 1-year-old boy who developed protein-losing enteropathy (PLE) within 2 months of a fenestrated Fontan procedure. His fenestration rapidly closed despite bilateral pulmonary stenosis (BPS). Subsequent to PLE onset, both fenestration and the bilateral pulmonary artery were reconstructed, and the patient's PLE had been in remission, with additive use of medications, for more than 2 years. Notably, although fenestration closed again and central venous pressure (CVP) reduction was minimal, the surrogates of venous return resistance were markedly suppressed as shown by increased blood volume, reduced estimated mean circulatory filling pressure, and suppressed CVP augmentation against a contrast agent. Taken together, dynamic characteristics of venous stagnation, rather than the absolute value of CVP, were ameliorated by the pulmonary reconstruction and use of medications, suggesting a significant role of venous property in the physiology of PLE. In addition, simultaneous measures of CVP and ventricular end-diastolic pressure during the abdominal compression procedure suggested a limited therapeutic role of fenestration against PLE in this patient.


Assuntos
Pressão Venosa Central/fisiologia , Técnica de Fontan/efeitos adversos , Enteropatias Perdedoras de Proteínas/complicações , Estenose da Valva Pulmonar/etiologia , Hemodinâmica/fisiologia , Humanos , Síndrome do Coração Esquerdo Hipoplásico/diagnóstico , Síndrome do Coração Esquerdo Hipoplásico/cirurgia , Lactente , Masculino , Complicações Pós-Operatórias/fisiopatologia , Enteropatias Perdedoras de Proteínas/fisiopatologia , Estenose da Valva Pulmonar/fisiopatologia , Remissão Espontânea
4.
Best Pract Res Clin Anaesthesiol ; 35(2): 231-240, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34030807

RESUMO

In patients undergoing craniotomy, general anesthesia should be addressed to warrant good hypnosis, immobility, and analgesia, to ensure systemic and cerebral physiological status and provide the best possible surgical field. Regarding craniotomies, it is unclear if there are substantial differences in providing general anesthesia using total intravenous anesthesia (TIVA) or balanced anesthesia (BA) accomplished using the third generation halogenates. New evidence highlighted that the last generation of halogenated agents has possible advantages compared with intravenous drugs: rapid induction, minimal absorption and metabolization, reproducible pharmacokinetic, faster recovery, cardioprotective effect, and opioid spare analgesia. This review aims to report evidence related to the use of the latest halogenated agents in patients undergoing craniotomy and to present available clinical evidence on their effects: cerebral and systemic hemodynamic, neurophysiological monitoring, and timing and quality of recovery after anesthesia.


Assuntos
Período de Recuperação da Anestesia , Anestesia Geral/métodos , Anestesia por Inalação/métodos , Procedimentos Neurocirúrgicos/métodos , Anestesia Geral/efeitos adversos , Anestesia por Inalação/efeitos adversos , Encéfalo/efeitos dos fármacos , Encéfalo/fisiologia , Desflurano/administração & dosagem , Hemodinâmica/efeitos dos fármacos , Hemodinâmica/fisiologia , Humanos
5.
Heart Fail Clin ; 17(3): 423-434, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34051974

RESUMO

Noninvasive cardiac imaging by transthoracic echocardiography is among the first-line assessments in evaluation of heart failure patients with preserved ejection fraction (HFpEF). Although systolic function seems preserved by conventional measurers, important information is found through examination of the heart's hemodynamic profile through Doppler and novel echocardiographic measures. These measures aid in establishing the diagnosis of HFpEF and provide valuable prognostic information. Targets of interest include the left ventricle diastolic function, atrial structure and function, and right ventricular function including pulmonary pressures. Contemporary assessments of the hemodynamic profile attainable through echocardiography in HFpEF at rest are reviewed and future directions outlined.


Assuntos
Ecocardiografia/métodos , Átrios do Coração/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Volume Sistólico/fisiologia , Função Ventricular Esquerda/fisiologia , Átrios do Coração/fisiopatologia , Insuficiência Cardíaca/diagnóstico , Hemodinâmica/fisiologia , Humanos , Prognóstico
6.
J Vis Exp ; (170)2021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33999028

RESUMO

During metastasis, cancer cells from solid tissues, including epithelia, gain access to the lymphatic and hematogenous circulation where they are exposed to mechanical stress due to hemodynamic flow. One of these stresses that circulating tumor cells (CTCs) experience is fluid shear stress (FSS). While cancer cells may experience low levels of FSS within the tumor due to interstitial flow, CTCs are exposed, without extracellular matrix attachment, to much greater levels of FSS. Physiologically, FSS ranges over 3-4 orders of magnitude, with low levels present in lymphatics (<1 dyne/cm2) and the highest levels present briefly as cells pass through the heart and around heart valves (>500 dynes/cm2). There are a few in vitro models designed to model different ranges of physiological shear stress over various time frames. This paper describes a model to investigate the consequences of brief (millisecond) pulses of high-level FSS on cancer cell biology using a simple syringe and needle system.


Assuntos
Hemodinâmica/fisiologia , Células Neoplásicas Circulantes/imunologia , Humanos , Seringas
7.
Am J Med Sci ; 361(6): 731-735, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33947586

RESUMO

BACKGROUND: The relationship between the presence of pleural and pericardial effusion in reference to hemodynamic parameters remains unclear in ambulatory patients with pulmonary hypertension (PH). METHODS: Consecutive patients who underwent right catheterization (RHC) for the evaluation of pulmonary hypertension were enrolled. Point-of- care ultrasound was performed prior to the RHC to determine the presence of pleural effusion and pericardial effusion. We conducted a cross-sectional study to determine the association between presence of pericardial and pleural effusion with pulmonary hemodynamic variables. RESULTS: Twenty-five (78.1%) of 32 patients had evidence of PH by RHC. Mean pulmonary artery pressure of the population was 40.6 mmHg, and 68% (17/25) had WHO group I PH. Six (24.0%) of 25 PH patients had pleural effusions identified, of which 4 out of 6 (66.7%) had a pulmonary artery wedge pressure >15 mmHg. Eleven (44.0%) of the 25 PH patients were also found to have pericardial effusions, and most of those patients 10/11(90.9%) had an elevated right atrial pressure >10 mmHg. The presence of a pleural effusion was associated with a pulmonary artery wedge pressure >15 mmHg (p = 0.032) and the presence of a pericardial effusion was associated with a right atrial pressure >10 mmHg (p = 0.004). Detection of pleural effusion had a poor positive predictive value (67%) for the presence of pulmonary venous hypertension, whereas presence of a pericardial effusion was highly predictive (89%) of the presence of systemic venous hypertension. CONCLUSIONS: Systemic venous hypertension was associated with the presence of pericardial effusions, while pulmonary venous hypertension is associated with pleural effusion development in ambulatory patients with pulmonary hypertension.


Assuntos
Hemodinâmica/fisiologia , Hipertensão Pulmonar/diagnóstico por imagem , Derrame Pericárdico/diagnóstico por imagem , Derrame Pleural/diagnóstico por imagem , Ultrassonografia de Intervenção/métodos , Adulto , Idoso , Cateterismo Cardíaco/métodos , Estudos Transversais , Feminino , Humanos , Hipertensão Pulmonar/epidemiologia , Hipertensão Pulmonar/fisiopatologia , Masculino , Pessoa de Meia-Idade , Derrame Pericárdico/epidemiologia , Derrame Pericárdico/fisiopatologia , Derrame Pleural/epidemiologia , Derrame Pleural/fisiopatologia , Testes Imediatos
8.
BMC Surg ; 21(1): 185, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33827537

RESUMO

BACKGROUND: Despite the unequivocal role of progressive mobilization in post-surgical patient management, its specific effects and timing, particularly after abdominal surgery, remain debated. This study's aim was to examine the short-term effects of mobilization on oxygenation in hemodynamically stable patients after open surgery for pancreatic cancer. METHODS: A randomized controlled clinical trial was conducted in which patients (n = 83) after open pancreatic surgery were randomized to either the same-day mobilization group (mobilized when hemodynamically stable within four hours after surgery) or the next-day mobilization group (mobilized first time in the morning of the first post-operative day). Mobilization was prescribed and modified based on hemodynamic and subjective responses with the goal of achieving maximal benefit with minimal risk. Blood gas samples were taken three times the evening after surgery; and before and after mobilization on the first post-operative day. Spirometry was conducted pre-operatively and on the first post-operative day. Adverse events and length of stay in postoperative intensive care were also recorded. RESULTS: With three dropouts, 80 patients participated (40 per group). All patients in the same-day mobilization group, minimally sat over the edge of the bed on the day of surgery and all patients (both groups) minimally sat over the edge of the bed the day after surgery. Compared with patients in the next-day mobilization group, patients in the same-day mobilization group required lower FiO2 and had higher SaO2/FiO2 at 1800 h on the day of surgery (p < .05). On the day after surgery, FiO2, SaO2/FiO2, PaO2/FiO2, and alveolar-arterial oxygen gradient, before and after mobilization, were superior in the same-day mobilization group (p < 0.05). No differences were observed between groups in PCO2, pH, spirometry or length stay in postoperative intensive care. CONCLUSIONS: Compared with patients after open pancreatic surgery in the next-day mobilization group, those in the same-day mobilization group, once hemodynamically stable, improved oxygenation to a greater extent after mobilization. Our findings support prescribed progressive mobilization in patients after pancreatic surgery (when hemodynamically stable and titrated to their individual responses and safety considerations), on the same day of surgery to augment oxygenation, potentially helping to reduce complications and hasten functional recovery. TRIAL REGISTRATION: This prospective RCT was carried out at the Sahlgrenska University Hospital, Sweden. The study was approved by the Regional Ethical Review Board in Gothenburg (Registration number: 437-17). TRIAL REGISTRATION: "FoU in Sweden" (Research and Development in Sweden, URL: https://www.researchweb.org/is/vgr ) id: 238701 Registered 13 December 2017 and Clinical Trials (URL:clinicaltrials.gov) NCT03466593. Registered 15 March 2018.


Assuntos
Deambulação Precoce , Neoplasias Pancreáticas , Cuidados Pós-Operatórios , Hemodinâmica/fisiologia , Humanos , Neoplasias Pancreáticas/reabilitação , Neoplasias Pancreáticas/cirurgia , Estudos Prospectivos , Suécia , Resultado do Tratamento
9.
Int J Mol Sci ; 22(9)2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33925045

RESUMO

Glaucomatous optic neuropathies have been regarded as diseases caused by high intraocular pressure for a long time, despite the concept of vascular glaucoma dating back to von Graefe in 1854. Since then, a tremendous amount of knowledge about the ocular vasculature has been gained; cohort studies have established new vascular risk factors for glaucoma as well as identifying protective measures acting on blood vessels. The knowledge about the physiology and pathophysiology of the choroidal, retinal, as well as ciliary and episcleral circulation has also advanced. Only recently have novel drugs based on that knowledge been approved for clinical use, with more to follow. This review provides an overview of the current vascular concepts in glaucoma, ranging from novel pathogenesis insights to promising therapeutic approaches, covering the supply of the optic nerve head as well as the aqueous humor production and drainage system.


Assuntos
Glaucoma/etiologia , Animais , Circulação Sanguínea/fisiologia , Pressão Sanguínea/fisiologia , Olho/irrigação sanguínea , Glaucoma/tratamento farmacológico , Glaucoma/fisiopatologia , Hemodinâmica/fisiologia , Humanos , Pressão Intraocular/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Fatores de Risco
10.
Medicine (Baltimore) ; 100(14): e25299, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33832099

RESUMO

ABSTRACT: Intradialytic hypotension (IDH) may lead to a poor life quality and was associated with cardiovascular mortality in patients under hemodialysis. This study investigated the autonomic nerve and cardiovascular function in the IDH episodes.In this case-control study, 70 end stage renal disease patients (198 visits) were recruited. Pulse wave analysis and heart rate variability were evaluated before hemodialysis. Two definitions of IDH were confirmed by medical records. IDH-f indicated a drop of systolic blood pressure or mean arterial pressure, accompanied with symptoms; IDH-n indicated a low nadir systolic pressure during the hemodialysis. All parameters were evaluated for the possible predisposing factors under each definition.A total of 24 IDH-f and 37 IDH-n were noted in 177 visits. For both definitions, central pulse pressure seemed to be a consistent predisposing factor. Furthermore, lower sympathetic activity (odds ratio [OR] 0.55; 95% confidence interval [CI] 0.35-0.87), lower pulse pressure (OR 0.95; 95% CI 0.92-0.98), and higher augmentation index (OR 17.36; 95% CI 1.48-204.10) were the possible predisposing factors for IDH-f. On the contrary, lower mean arterial pressure (OR 0.87; 95% CI 0.78-0.98) was identified as the possible factor for IDH-n.It was suggested that the lower central pulse pressure and sympathetic activity might be involved in the development of IDH.


Assuntos
Hemodinâmica/fisiologia , Hipotensão/etiologia , Hipotensão/fisiopatologia , Falência Renal Crônica/terapia , Diálise Renal/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea/fisiologia , Estudos de Casos e Controles , Frequência Cardíaca , Humanos , Pessoa de Meia-Idade , Análise de Onda de Pulso
11.
J Cardiovasc Surg (Torino) ; 62(4): 354-363, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33829743

RESUMO

BACKGROUND: Transcranial Doppler ultrasound (TCD) is a frequently used method to monitor brain perfusion during and following carotid endarterectomy (CEA). Our aim was to define the normally occurring changes of intracranial hemodynamics in patients undergoing CEA measuring recently developed TCD parameters. METHODS: A retrospective, single-center cohort study was performed. Patients undergoing CEA were evaluated pre- and postoperatively from day 0 to day 3 measuring middle cerebral artery flow velocity (MCAFV). The following parameters were analyzed: the first systolic peak (Sys1), the second systolic peak (Sys2) and diastolic flow velocity at a fixed time after heartbeat onset (Dias@560). These parameters linearly decrease with age and were, therefore, transformed to Z-scores. RESULTS: Three hundred eighteen patients were included with a mean age of 70.8 years. Most patients were male (71%). Compared to preoperatively, the Z-scores of Sys1 and Sys2 were larger on postoperative day 3: +1.12 standard deviation (SD) or 16.0 cm/s (CI: 0.93 to 1.32; P<0.001) and +0.55 SD or 7.8 cm/s (CI: 0.35 to 0.74; P<0.001), respectively. The Z-score for Dias@560 was smaller than preoperatively: -0.23 SD or -1.9 cm/s (CI: -0.41 to -0.05, P=0.015). CONCLUSIONS: Under normal circumstances Sys1 profits more from CEA than Sys2, whilst diastolic flow velocity decreases. This indicates a return to normal arteriolar vascular resistance. Carefully describing normal changes in MCAFV, may in future enable discrimination of abnormalities, such as hyperperfusion syndrome.


Assuntos
Estenose das Carótidas/cirurgia , Circulação Cerebrovascular/fisiologia , Endarterectomia das Carótidas , Artéria Cerebral Média/diagnóstico por imagem , Ultrassonografia Doppler Transcraniana/métodos , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estenose das Carótidas/diagnóstico , Estenose das Carótidas/fisiopatologia , Feminino , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/fisiopatologia , Período Pós-Operatório , Estudos Retrospectivos , Sístole
12.
Am J Physiol Lung Cell Mol Physiol ; 320(6): L1126-L1136, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33826416

RESUMO

Intravenous fluids are widely used to treat circulatory deterioration in pediatric acute respiratory distress syndrome (PARDS). However, the accumulation of fluids in the first days of PARDS is associated with adverse outcome. As such, early fluid restriction may prove beneficial, yet the effects of such a fluid strategy on the cardiopulmonary physiology in PARDS are unclear. In this study, we compared the effect of a restrictive with a liberal fluid strategy on a hemodynamic response and the formation of pulmonary edema in an animal model of PARDS. Sixteen mechanically ventilated lambs (2-6 wk) received oleic acid infusion to induce PARDS and were randomized to a restrictive or liberal fluid strategy during a 6-h period of mechanical ventilation. Transpulmonary thermodilution determined extravascular lung water (EVLW) and cardiac output (CO). Postmortem lung wet-to-dry weight ratios were obtained by gravimetry. Restricting fluids significantly reduced fluid intake but increased the use of vasopressors among animals with PARDS. Arterial blood pressure was similar between groups, yet CO declined significantly in animals receiving restrictive fluids (P = 0.005). There was no difference in EVLW over time (P = 0.111) and lung wet-to-dry weight ratio [6.1, interquartile range (IQR) = 6.0-7.3 vs. 7.1, IQR = 6.6-9.4, restrictive vs. liberal, P = 0.725] between fluid strategies. Both fluid strategies stabilized blood pressure in this model, yet early fluid restriction abated CO. Early fluid restriction did not limit the formation of pulmonary edema; therefore, this study suggests that in the early phase of PARDS, a restrictive fluid strategy is not beneficial in terms of immediate cardiopulmonary effects.


Assuntos
Água Extravascular Pulmonar/metabolismo , Hidratação , Hemodinâmica/fisiologia , Síndrome do Desconforto Respiratório/terapia , Animais , Água Extravascular Pulmonar/fisiologia , Hidratação/métodos , Respiração Artificial/métodos , Síndrome do Desconforto Respiratório/metabolismo , Ressuscitação/métodos , Ovinos , Fatores de Tempo
13.
Pediatr Cardiol ; 42(5): 1180-1189, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33876263

RESUMO

It is unclear whether residual anterograde pulmonary blood flow (APBF) at the time of Fontan is beneficial. Pulsatile pulmonary flow may be important in maintaining a compliant and healthy vascular circuit. We, therefore, wished to ascertain whether there was hemodynamic evidence that residual pulsatile flow at time of Fontan promotes clinical benefit. 106 consecutive children with Fontan completion (1999-2018) were included. Pulmonary artery pulsatility index (PI, (systolic pressure-diastolic pressure)/mean pressure)) was calculated from preoperative cardiac catheterization. Spectral analysis charted PI as a continuum against clinical outcome. The population was subsequently divided into three pulsatility subgroups to facilitate further comparison. Median PI prior to Fontan was 0.236 (range 0-1). 39 had APBF, in whom PI was significantly greater (median: 0.364 vs. 0.177, Mann-Whitney p < 0.0001). There were four early hospital deaths (3.77%), and PI in these patients ranged from 0.214 to 0.423. There was no correlation between PI and standard cardiac surgical outcomes or systemic oxygen saturation at discharge. Median follow-up time was 4.33 years (range 0.0273-19.6), with no late deaths. Increased pulsatility was associated with higher oxygen saturations in the long term, but there was no difference in reported exercise tolerance (Ross), ventricular function, or atrioventricular valve regurgitation at follow-up. PI in those with Fontan-associated complications or the requiring pulmonary vasodilators aligned with the overall population median. Maintenance of pulmonary flow pulsatility did not alter short-term outcomes or long-term prognosis following Fontan although it tended to increase postoperative oxygen saturations, which may be beneficial in later life.


Assuntos
Técnica de Fontan/métodos , Circulação Pulmonar/fisiologia , Coração Univentricular/cirurgia , Adolescente , Criança , Pré-Escolar , Feminino , Cardiopatias Congênitas/cirurgia , Hemodinâmica/fisiologia , Humanos , Lactente , Masculino , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
14.
Am J Physiol Heart Circ Physiol ; 320(5): H2011-H2030, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33797272

RESUMO

Preeclampsia is a worldwide pregnancy complication with serious short- and long-term maternal and neonatal consequences. Our understanding of preeclampsia pathophysiology has significantly evolved over the last decades with the recognition that impaired arterial function and structure may occur early in the course of pregnancy, preceding the clinic-humoral syndrome and driving long-term cardiovascular disease risk in the future of these patients. Although an early abnormal placentation may be the inciting event for a large proportion of cases, there is growing evidence that challenges the placental hypothesis in all affected women, since placental histopathology lesions thought to be characteristic are neither sensitive nor specific markers for the disorder. Recent hemodynamic investigations and studies on left ventricular function and structure in women with preeclampsia further challenge this universal paradigm and propose that placental dysfunction could be secondary to a maternal cardiovascular maladaptation to pregnancy in certain patients. Supporting this hypothesis, certain vascular features, which are characteristically enhanced in normal pregnancy allowing a healthy vascular adaptation, are absent in preeclampsia and comparable to the nonpregnant population. However, arterial biomechanics in preeclampsia may only not cope with hemodynamic demands of pregnancy but also impose additional detrimental loads to the maternal heart ("impaired left-ventricle-aorta coupling") and transmit pressure and flow disturbances into the fetoplacental circulation ("impaired large arteries-microcirculation coupling"). In this review, we analyze the major role of the arterial dysfunction in the cardiovascular maladaptation hypothesis of preeclampsia, shed light on its potential etiopathogenic link, and discuss the complementary nature of the placental and cardiovascular theories.


Assuntos
Artérias/fisiopatologia , Endotélio Vascular/fisiopatologia , Hemodinâmica/fisiologia , Pré-Eclâmpsia/fisiopatologia , Rigidez Vascular/fisiologia , Espessura Intima-Media Carotídea , Feminino , Humanos , Placenta/irrigação sanguínea , Gravidez
15.
Am J Physiol Heart Circ Physiol ; 320(5): H2161-H2168, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33834869

RESUMO

Right ventricular failure (RVF) is a serious adverse event after left ventricular assist device (LVAD) implantation but difficult to be characterized. This study aimed to visualize the dynamic circulatory equilibrium of acute RVF after LVAD implantation using a new four-quadrant diagram constructed by 1) cardiac function with central venous pressure (CVP) and cardiac index (CI) axes, 2) arterial vascular resistance with CI and mean blood pressure (mBP) axes, 3) pressure-diuretic function with mBP and net urinary sodium output (net U-Na) axes, and 4) venous compliance with net U-Na and CVP axes. Twenty LVAD patients were stratified into two groups, group S (≤10 days) and group L (>10 days), according to duration of postoperative inotropic support. The preoperative equilibrium loops were small in both groups. In the early postoperative phase, the loop in group S became dramatically enlarged to the left and upward, indicating increased CVP and CI by LVAD support. In group L, however, augmentation of CI was smaller despite similarly increased CVP, and net U-Na was decreased despite increased mBP. In the late postoperative phase, the equilibrium loop in group L recovered as similar to that seen in group S. Thus, acute RVF, as shown in group L, was characterized by the shape of the loop constructed by marked increased CVP, a relatively small increase in CI, and concomitant impairment of pressure natriuresis. In conclusion, the novel four-quadrant presentation of systemic circulatory equilibrium provides clear visualization of RVF after LVAD implantation, thus serving as a useful guide for prompt and optimal management.NEW & NOTEWORTHY Systemic circulatory dynamics are regulated by various negative feedback systems, including cardiac, arterial, venous, and renal functions, as well as autonomic nervous systems. The present novel four-quadrant presentation of their functions allows clear visualization of dynamic organ-to-organ interactions that can lead to a new circulatory equilibrium after therapeutic intervention. This new system physiological framework can serve as a useful guide for prompt and optimal management of circulatory malfunction.


Assuntos
Insuficiência Cardíaca/diagnóstico por imagem , Coração Auxiliar , Hemodinâmica/fisiologia , Disfunção Ventricular Direita/diagnóstico por imagem , Adulto , Pressão Venosa Central/fisiologia , Ecocardiografia , Feminino , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Disfunção Ventricular Direita/fisiopatologia
16.
Cardiovasc Intervent Radiol ; 44(8): 1251-1259, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33907900

RESUMO

PURPOSE: The multilayer flow modulator (MFM) device has been used for the treatment of abdominal aortic aneurysm (AAA) for over a decade. Although several clinical studies have been published, criticism and concern over the device efficacy remain, as no quantitative analysis that describes its mechanism has been performed yet. The aim of this study was to experimentally evaluate the effect of MFM device deployment on aneurysmal pressure and branch perfusion. MATERIALS AND METHODS: An experimental flow and pressure monitoring system was developed to analyze the MFM deployment procedure performed by a qualified radiologist in AAA geometries with and without side branch. Particle image velocimetry experiments were then conducted on models with and without MFM device to evaluate and compare flow patterns and local flow velocity and vorticity in the aneurysm. RESULTS: The experiments revealed no significant change in pressure and flow rate during and after deployment of the MFM device. The flow rate of the incorporated branch was fully preserved. On both models, the aneurysmal flow velocity was significantly reduced. In addition, the device modified local flow patterns, reducing vorticity and better feeding the incorporated branch. CONCLUSION: This experimental study provides the basis for a better understanding of the mechanism of the MFM device, which allows intra-aneurysmal flow to decrease while preserving incorporated branch flow and reducing the risk of type II endoleak. The experimental system developed for this study was effective in simulating an endovascular procedure and studying the safety and effectiveness of endovascular devices.


Assuntos
Aneurisma da Aorta Abdominal/fisiopatologia , Aneurisma da Aorta Abdominal/cirurgia , Procedimentos Endovasculares/métodos , Hemodinâmica/fisiologia , Modelos Biológicos , Velocidade do Fluxo Sanguíneo , Desenho de Equipamento , Humanos , Masculino , Resultado do Tratamento
17.
Pediatr Cardiol ; 42(6): 1356-1364, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33881601

RESUMO

The study aimed to assess the long-term outcomes after fenestration closure in patients at risk for Fontan failure. Of 119 patients who underwent Fontan operation between 1995 and 2004, fenestration was not created in 89 patients (NF group) and created in 30 patients with hypoplastic left heart syndrome, heterotaxy syndrome, high pulmonary arterial pressure, high systemic ventricular end-diastolic pressure, low ventricular ejection fraction, or atrioventricular valve regurgitation. All fenestrations were closed spontaneously or by catheter/surgical interventions, excepting two patients, and therefore, they were excluded. In fenestration group, patients with pre-Fontan mean pulmonary arterial pressure ≥ 15 mmHg or systemic atrioventricular valve regurgitation ≥ moderate were classified as high-risk Fontan candidates (F-HR group, n = 16), and the remaining patients were as standard-risk (F-SR group, n = 12). Protein-losing enteropathy-free survival rates did not differ among the three groups (p = 0.72). Serial follow-up catheter examinations after Fontan operation were completed in 69 patients in NF group and 11 patients in both F-SR and F-HR groups. Cardiac index and pulmonary vascular resistance significantly and similarly decreased over time in all groups, though the F-HR group showed lowest arterial oxygen saturation, lowest cardiac index, and highest pulmonary vascular resistance. The F-HR group also showed much veno-venous collaterals (p = 0.049), low peak oxygen consumption (p = 0.019), and low anaerobic threshold (p = 0.023) as compared to those in the F-SR group. In F-HR group, cyanosis remained after fenestration closure due to transformation from fenestration to veno-venous collaterals, which resulted in elevation of pulmonary vascular resistance, low cardiac index, and deterioration of exercise tolerance.


Assuntos
Técnica de Fontan/métodos , Cardiopatias Congênitas/cirurgia , Hemodinâmica/fisiologia , Cateterismo Cardíaco/métodos , Criança , Pré-Escolar , Feminino , Seguimentos , Cardiopatias Congênitas/fisiopatologia , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Fatores de Tempo , Resultado do Tratamento
18.
J Neuroimaging ; 31(3): 428-445, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33856735

RESUMO

Vascular malformations (VMs) of the central nervous system (CNS) include a wide range of pathological conditions related to intra and extracranial vessel abnormalities. Although some VMs show typical neuroimaging features, other VMs share and overlap pathological and neuroimaging features that hinder an accurate differentiation between them. Hence, it is not uncommon to misclassify different types of VMs under the general heading of arteriovenous malformations. Thorough knowledge of the imaging findings of each type of VM is mandatory to avoid these inaccuracies. Conventional MRI sequences, including MR angiography, have allowed the evaluation of CNS VMs without using ionizing radiation. Newer MRI techniques, such as susceptibility-weighted imaging, black blood sequences, arterial spin labeling, and 4D flow imaging, have an added value of providing physiopathological data in real time regarding the hemodynamics of VMs. Beyond MR images, new insights using 3D printed models are being incorporated as part of the armamentarium for a noninvasive evaluation of VMs. In this paper, we briefly review the pathophysiology of CNS VMs, focusing on the MRI findings that may be helpful to differentiate them. We discuss the role of each conventional and advanced MRI sequence for VMs assessment and provide some insights about the value of structured reports of 3D printing to evaluate VMs.


Assuntos
Malformações Vasculares do Sistema Nervoso Central/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos , Adulto , Sistema Nervoso Central/irrigação sanguínea , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Marcadores de Spin
19.
Pediatr Cardiol ; 42(6): 1410-1415, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33914123

RESUMO

For patients with single ventricle physiology, being able to initially establish systemic blood flow and control pulmonary blood flow is critical to their long-term health. Recently, there have been descriptions in achieving this by a purely transcatheter approach with stenting of the ductus arteriosus and implanting pulmonary flow restrictors, a very appealing prospect. We review a case series of 6 patients who underwent a percutaneous modified stage 1 approach using modified Microvascular plugs (MVP) at our center between September 2019 and December 2019. The initial procedure was technically successful in all patients with single-stage ductal stenting and placement of bilateral modified MVP via femoral access. Four patients underwent repeat cardiac catheterization prior to subsequent surgery that demonstrated elevated Qp:Qs (> 2:1) in 3 of the 4 patients with an elevated mean distal PA pressure > 20 mmHg in all patients. In some patients, the device migrated into the distal right pulmonary artery. One patient after Glenn shunt was found to have significant LPA stenosis requiring stenting. While the percutaneous modified stage 1 approach is a promising approach, we offer a word of caution against widespread adoption of this technique with the currently available devices.


Assuntos
Cateterismo Cardíaco/métodos , Permeabilidade do Canal Arterial/cirurgia , Canal Arterial/cirurgia , Hemodinâmica/fisiologia , Artéria Pulmonar/cirurgia , Stents , Permeabilidade do Canal Arterial/fisiopatologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Circulação Pulmonar , Fatores de Tempo , Resultado do Tratamento
20.
World J Pediatr Congenit Heart Surg ; 12(2): 176-184, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33684010

RESUMO

BACKGROUND: Early warning systems that utilize dense physiologic data and machine learning may aid prediction of decompensation after congenital heart surgery (CHS). The Compensatory Reserve Index (CRI) analyzes changing features of the pulse waveform to predict hemodynamic decompensation in adults, but it has never been studied after CHS. This study sought to understand the feasibility, safety, and potential utility of CRI monitoring after CHS with cardiopulmonary bypass (CPB). METHODS: A single-center prospective pilot cohort of patients undergoing pulmonary valve replacement was studied. Compensatory Reserve Index was continuously measured from preoperative baseline through the first 24 postoperative hours. Average CRI values during selected procedural phases were compared between patients with an intensive care unit (ICU) length of stay (LOS) <3 days versus LOS ≥3 days. RESULTS: Twenty-three patients were enrolled. On average, 17,445 (±3,152) CRI data points were collected and 0.33% (±0.40) of data were missing per patient. There were no adverse events related to monitoring. Five (21.7%) patients had an ICU LOS ≥3 days. Compared to the ICU LOS <3 days group, the ICU LOS ≥3 days group had a greater decrease in CRI from baseline to immediately after CPB (-0.3 ± 0.1 vs -0.1 ± 0.2, P = .003) and were less likely to recover to baseline CRI during the monitoring period (20% vs 83%, P = .017). CONCLUSIONS: Compensatory Reserve Index monitoring after CHS with CPB seems feasible and safe. Early changes in CRI may precede meaningful clinical outcomes, but this requires further study.


Assuntos
Procedimentos Cirúrgicos Cardíacos/métodos , Ponte Cardiopulmonar/métodos , Cardiopatias Congênitas/cirurgia , Hemodinâmica/fisiologia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Cardiopatias Congênitas/fisiopatologia , Humanos , Tempo de Internação , Masculino , Projetos Piloto , Período Pós-Operatório , Estudos Prospectivos , Adulto Jovem
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