Artykuły w czasopismach: „Haemodynamics”

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Kuboki, Takuo, Kenji Maekawa i Glenn Clark. "Intramuscular haemodynamics using near infra-red spectroscopy as a research strategy to understand chronic muscle pain pathophysiology". Spectroscopy 19, nr 1 (2005): 27–36. http://dx.doi.org/10.1155/2005/148586.

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Recently, localized intramuscular haemodynamic disturbance has been recognized as one of the cardinal features of a chronically painful muscle. To test this hypothesis, we have carried out several studies that have assessed intramuscular haemodynamics to understand more about haemodynamic alteration under conditions of an experimentally induced vasoreactive challenges in healthy controls and in patients with chronic muscle pain using near infra?red (NIR) spectroscopy. In addition, we have validated the NIR based haemodynamic signals by comparing against a water signal intensity change taken from a transverse T2?weighted magnetic resonance image (MRI) of the muscles. As a result, we discovered that muscle pain patients have a diminished ability to vasodilate in painful muscle. We also provided powerful evidences that NIR data (total haemoglobin level), transcutaneously taken from the muscles in humans could be an analogue of intramuscular haemodynamics.

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Hartkamp, Nolan S., Esben T. Petersen, Michael A. Chappell, Thomas W. Okell, Maarten Uyttenboogaart, Clark J. Zeebregts i Reinoud PH Bokkers. "Relationship between haemodynamic impairment and collateral blood flow in carotid artery disease". Journal of Cerebral Blood Flow & Metabolism 38, nr 11 (4.08.2017): 2021–32. http://dx.doi.org/10.1177/0271678x17724027.

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Collateral blood flow plays a pivotal role in steno-occlusive internal carotid artery (ICA) disease to prevent irreversible ischaemic damage. Our aim was to investigate the effect of carotid artery disease upon cerebral perfusion and cerebrovascular reactivity and whether haemodynamic impairment is influenced at brain tissue level by the existence of primary and/or secondary collateral. Eighty-eight patients with steno-occlusive ICA disease and 29 healthy controls underwent MR examination. The presence of collaterals was determined with time-of-flight, two-dimensional phase contrast MRA and territorial arterial spin labeling (ASL) imaging. Cerebral blood flow and cerebrovascular reactivity were assessed with ASL before and after acetazolamide. Cerebral haemodynamics were normal in asymptomatic ICA stenosis patients, as opposed to patients with ICA occlusion, in whom the haemodynamics in both hemispheres were compromised. Haemodynamic impairment in the affected brain region was always present in symptomatic patients. The degree of collateral blood flow was inversely correlated with haemodynamic impairment. Recruitment of secondary collaterals only occurred in symptomatic ICA occlusion patients. In conclusion, both CBF and cerebrovascular reactivity were found to be reduced in symptomatic patients with steno-occlusive ICA disease. The presence of collateral flow is associated with further haemodynamic impairment. Recruitment of secondary collaterals is associated with severe haemodynamic impairment.

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Raj, Leah M., i Leslie A. Saxon. "Haemodynamic Monitoring Devices in Heart Failure: Maximising Benefit with Digitally Enabled Patient Centric Care". Arrhythmia & Electrophysiology Review 7, nr 4 (2018): 1. http://dx.doi.org/10.15420/aer.2018.32.3.

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ICDs and resynchronisation devices are routinely implanted in patients with heart failure for primary prevention of sudden cardiac death or to treat the condition. The addition of device features and algorithms that directly or indirectly monitor cardiac haemodynamics to assess heart failure status can provide additional benefit by treating heart failure more continuously. Established and emerging devices and sensors aimed at treating or measuring cardiac haemodynamics represent the next era of heart failure disease management. Digitally enabled models of heart failure care, based on frequent haemodynamic measurements, will increasingly involve patients in their own disease management. Software tools and services tailored to provide patients with personalised information to guide diet, activity, medications and haemodynamic management offer an unprecedented opportunity to improve patient outcomes. This will enable physicians to care for larger populations because management will be exception based, automated and no longer depend on one-to-one patient and physician interactions.

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Bull, C. "Haemodynamics". Current Opinion in Cardiology 1, nr 1 (styczeń 1986): 88–92. http://dx.doi.org/10.1097/00001573-198601000-00016.

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Oslizlok, P. "Haemodynamics". Current Opinion in Cardiology 2, nr 1 (styczeń 1987): 118–22. http://dx.doi.org/10.1097/00001573-198701010-00023.

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Bull, C. "Haemodynamics". Current Opinion in Cardiology 3, nr 1 (styczeń 1988): 71–77. http://dx.doi.org/10.1097/00001573-198801000-00012.

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Obokata, Masaru, Thomas P. Olson, Yogesh N. V. Reddy, Vojtech Melenovsky, Garvan C. Kane i Barry A. Borlaug. "Haemodynamics, dyspnoea, and pulmonary reserve in heart failure with preserved ejection fraction". European Heart Journal 39, nr 30 (19.05.2018): 2810–21. http://dx.doi.org/10.1093/eurheartj/ehy268.

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Abstract Aims Increases in left ventricular filling pressure are a fundamental haemodynamic abnormality in heart failure with preserved ejection fraction (HFpEF). However, very little is known regarding how elevated filling pressures cause pulmonary abnormalities or symptoms of dyspnoea. We sought to determine the relationships between simultaneously measured central haemodynamics, symptoms, and lung ventilatory and gas exchange abnormalities during exercise in HFpEF. Methods and results Subjects with invasively-proven HFpEF (n = 50) and non-cardiac causes of dyspnoea (controls, n = 24) underwent cardiac catheterization at rest and during exercise with simultaneous expired gas analysis. During submaximal (20 W) exercise, subjects with HFpEF displayed higher pulmonary capillary wedge pressures (PCWP) and pulmonary artery pressures, higher Borg perceived dyspnoea scores, and increased ventilatory drive and respiratory rate. At peak exercise, ventilation reserve was reduced in HFpEF compared with controls, with greater dead space ventilation (higher VD/VT). Increasing exercise PCWP was directly correlated with higher perceived dyspnoea scores, lower peak exercise capacity, greater ventilatory drive, worse New York Heart Association (NYHA) functional class, and impaired pulmonary ventilation reserve. Conclusion This study provides the first evidence linking altered exercise haemodynamics to pulmonary abnormalities and symptoms of dyspnoea in patients with HFpEF. Further study is required to identify the mechanisms by which haemodynamic derangements affect lung function and symptoms and to test novel therapies targeting exercise haemodynamics in HFpEF.

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Warmerdam, Evangeline, Gregor J. Krings, Tim Leiner i Heynric B. Grotenhuis. "Three-dimensional and four-dimensional flow assessment in congenital heart disease". Heart 106, nr 6 (19.12.2019): 421–26. http://dx.doi.org/10.1136/heartjnl-2019-315797.

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Congenital heart disease (CHD) is the most common form of congenital defects, with an incidence of 8 per 1000 births. Due to major advances in diagnostics, perioperative care and surgical techniques, the survival rate of patients with CHD has improved dramatically. Conversely, although 70%–95% of infants with CHD survive into adulthood, the rate of long-term morbidity, which often requires (repeat) intervention, has increased. Recently, the role of altered haemodynamics in cardiac development and CHD has become a subject of interest. Patients with CHD often have abnormal blood flow patterns, either due to the primary cardiac defect or as a consequence of the surgical intervention(s). Research suggests that these abnormal blood flow patterns may contribute to diminished cardiac and vascular function. Serial assessment of haemodynamic parameters in patients with CHD may allow for improved understanding of the often complex haemodynamics in these patients and thereby potentially guide the timing and nature of interventions with the aim of preventing progression of cardiovascular deterioration. In this article we will discuss two novel non-invasive four-dimensional (4D) techniques to evaluate cardiovascular haemodynamics: 4D-flow cardiac magnetic resonance and computational fluid dynamics. This review focuses on the additional value of these two modalities in the evaluation of patients with CHD with abnormal flow patterns, who could benefit from advanced haemodynamic evaluation: patients with coarctation of the aorta, bicuspid aortic valve, tetralogy of Fallot and patients after Fontan palliation.

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Kabir, MS, AAS Majumder, AFKU Ahmed, KA Rubaiyat, A. Jhan, ASMG Rabbani i SMS Haque. "Echocardiographic Evaluation of Pulmonary Haemodynamics - A Review". Cardiovascular Journal 13, nr 2 (15.04.2021): 200–216. http://dx.doi.org/10.3329/cardio.v13i2.52975.

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Pulmonary haemodynamic status has got significant clinical and prognostic significance both in structural and nonstructural heart diseases. But diagnostic accuracy depends on much care in evaluation and logical correlation of different echocardiographic parameters. Though the Doppler studies play crucial role in estimating Pulmonary haemodynamics, careful observation of 2-D measurements of different structures as well as RV systolic and diastolic function are vital issues to be addressed and correlated for diagnostic accuracy. Tricuspid Valve, RVOT and Pulmonary valve pathologies also demand vivid correlation while estimating PA pressures and pulmonary vascular resistance. Mere presence of elevated pulmonary artery systolic pressure is not enough to define pulmonary hypertension (PH). Before declaring a patient having PH a comprehensive evaluation of right heart haemodynamics is to be performed carefully to avoid unnecessary cardiac catheterization or to avoid inadvertent initiation of PH therapy. Cardiovasc. j. 2021; 13(2): 200-216

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Miranda, William R., Barry A. Borlaug, Donald J. Hagler, Heidi M. Connolly i Alexander C. Egbe. "Haemodynamic profiles in adult Fontan patients: associated haemodynamics and prognosis". European Journal of Heart Failure 21, nr 6 (23.01.2019): 803–9. http://dx.doi.org/10.1002/ejhf.1365.

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Oliveira, Rudolf K. F., Aaron B. Waxman, Manyoo Agarwal, Roza Badr Eslam i David M. Systrom. "Pulmonary haemodynamics during recovery from maximum incremental cycling exercise". European Respiratory Journal 48, nr 1 (28.04.2016): 158–67. http://dx.doi.org/10.1183/13993003.00023-2016.

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Assessment of cardiac function during exercise can be technically demanding, making the recovery period a potentially attractive diagnostic window. However, the validity of this approach for exercise pulmonary haemodynamics has not been validated.The present study, therefore, evaluated directly measured pulmonary haemodynamics during 2-min recovery after maximum invasive cardiopulmonary exercise testing in patients evaluated for unexplained exertional intolerance. Based on peak exercise criteria, patients with exercise pulmonary hypertension (ePH; n=36), exercise pulmonary venous hypertension (ePVH; n=28) and age-matched controls (n=31) were analysed.By 2-min recovery, 83% (n=30) of ePH patients had a mean pulmonary artery pressure (mPAP) <30 mmHg and 96% (n=27) of ePVH patients had a pulmonary arterial wedge pressure (PAWP) <20 mmHg. Sensitivity of pulmonary hypertension-related haemodynamic measurements during recovery for ePH and ePVH diagnosis was ≤25%. In ePVH, pulmonary vascular compliance (PVC) returned to its resting value by 1-min recovery, while in ePH, elevated pulmonary vascular resistance (PVR) and decreased PVC persisted throughout recovery.In conclusion, we observed that mPAP and PAWP decay quickly during recovery in ePH and ePVH, compromising the sensitivity of recovery haemodynamic measurements in diagnosing pulmonary hypertension. ePH and ePVH had different PVR and PVC recovery patterns, suggesting differences in the underlying pulmonary hypertension pathophysiology.

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Pons, Maria Isabel, Jordi Mill, Alvaro Fernandez-Quilez, Andy L. Olivares, Etelvino Silva, Tom de Potter i Oscar Camara. "Joint Analysis of Morphological Parameters and In Silico Haemodynamics of the Left Atrial Appendage for Thrombogenic Risk Assessment". Journal of Interventional Cardiology 2022 (14.03.2022): 1–10. http://dx.doi.org/10.1155/2022/9125224.

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Background. Atrial fibrillation (AF) is considered the most common human arrhythmia. In nonvalvular AF, around 99% of thrombi are formed in the left atrial appendage (LAA). Nevertheless, there is not a consensus in the community about the relevant factors to stratify the AF population according to thrombogenic risk. Objective. To demonstrate the need for combining left atrial morphological and haemodynamics indices to improve the thrombogenic risk assessment in nonvalvular AF patients. Methods. A cohort of 71 nonvalvular AF patients was analysed. Statistical analysis, regression models, and random forests were used to analyse the differences between morphological and haemodynamics parameters, extracted from computational simulations built on 3D rotational angiography images, between patients with and without transient ischemic attack (TIA) or cerebrovascular accident (CVA). Results. The analysis showed that models composed of both morphological and haemodynamic factors were better predictors of TIA/CVA compared with models based on either morphological or haemodynamic factors separately. Maximum ostium diameter, length of the centreline, blood flow velocity within the LAA, oscillatory shear index, and time average wall shear stress parameters were found to be key risk factors for TIA/CVA prediction. In addition, TIA/CVA patients presented more flow stagnation within the LAA. Conclusion. Thrombus formation in the LAA is the result of multiple factors. Analyses based only on morphological or haemodynamic parameters are not precise enough to predict such a phenomenon, as demonstrated in our results; a better patient stratification can be obtained by jointly analysing morphological and haemodynamic features.

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Kovacs, Gabor, Philippe Herve, Joan Albert Barbera, Ari Chaouat, Denis Chemla, Robin Condliffe, Gilles Garcia i in. "An official European Respiratory Society statement: pulmonary haemodynamics during exercise". European Respiratory Journal 50, nr 5 (listopad 2017): 1700578. http://dx.doi.org/10.1183/13993003.00578-2017.

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There is growing recognition of the clinical importance of pulmonary haemodynamics during exercise, but several questions remain to be elucidated. The goal of this statement is to assess the scientific evidence in this field in order to provide a basis for future recommendations.Right heart catheterisation is the gold standard method to assess pulmonary haemodynamics at rest and during exercise. Exercise echocardiography and cardiopulmonary exercise testing represent non-invasive tools with evolving clinical applications. The term “exercise pulmonary hypertension” may be the most adequate to describe an abnormal pulmonary haemodynamic response characterised by an excessive pulmonary arterial pressure (PAP) increase in relation to flow during exercise. Exercise pulmonary hypertension may be defined as the presence of resting mean PAP <25 mmHg and mean PAP >30 mmHg during exercise with total pulmonary resistance >3 Wood units. Exercise pulmonary hypertension represents the haemodynamic appearance of early pulmonary vascular disease, left heart disease, lung disease or a combination of these conditions. Exercise pulmonary hypertension is associated with the presence of a modest elevation of resting mean PAP and requires clinical follow-up, particularly if risk factors for pulmonary hypertension are present. There is a lack of robust clinical evidence on targeted medical therapy for exercise pulmonary hypertension.

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Siddique, Faias Karukappadath, Arun Aravind i Ashabi Mansoortheen. "A Prospective Randomized Study on Intraoperative Haemodynamic and Post-Operative Recovery Characteristics of Sevoflurane and Desflurane in Thyroid Surgeries under General Anaesthesia in Wayanad District". Journal of Evidence Based Medicine and Healthcare 8, nr 24 (14.06.2021): 2045–51. http://dx.doi.org/10.18410/jebmh/2021/384.

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BACKGROUND Maintaining deep plane of anaesthesia to prevent haemodynamic fluctuation and absolute immobility at the same time ensuring early and smooth recovery to prevent bleeding and assessing vocal cord status are the challenges to the anaesthesiologists in thyroid surgeries. Use of volatile anaesthetics with low solubility and low blood gas partition coefficient are used for their haemodynamic stability and faster emergence from anaesthesia in various surgeries under general anaesthesia. we wanted to compare sevoflurane and desflurane in terms of intraoperative haemodynamics, postoperative emergence and recovery characteristics in thyroid surgeries of less than 2 hours duration. METHODS After getting institutional ethical committee approval, 70 patients belonging to American Society of Anaesthesiologists (ASA), physical status I or II undergoing elective thyroid surgery were randomly assigned to two groups to receive either 6 % Desflurane (group D ) or 2 % Sevoflurane (group S) for maintenance of general anaesthesia along with 33 % oxygen with 67 % nitrous oxide. The intraoperative heart rate, mean arterial pressure were recorded at 5 minute intervals and recovery characteristics including times to extubation, first spontaneous motion, response to painful pinch, recall of name, hand grip and PARS score ≥ 9 were recorded in both groups. RESULTS There was no statistically significant difference (P > 0.05) in mean heart rate and mean arterial pressure between group D and S and remained within 20 % of baseline. The time to achieve a PARS ≥ 9 was earlier in the desflurane group and it was statistically significant. CONCLUSIONS Desflurane and Sevoflurane based anaesthesia provides comparable intraoperative haemodynamics whereas post-operative recovery was quicker in patients who received Desflurane compared to Sevoflurane. KEYWORDS Desflurane, Haemodynamics, Recovery, Sevoflurane

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Haggerty, Christopher M., Ajit P. Yoganathan i Mark A. Fogel. "Magnetic resonance imaging-guided surgical design: can we optimise the Fontan operation?" Cardiology in the Young 23, nr 6 (grudzień 2013): 818–23. http://dx.doi.org/10.1017/s1047951113001637.

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AbstractThe Fontan procedure, although an imperfect solution for children born with a single functional ventricle, is the only reconstruction at present short of transplantation. The haemodynamics associated with the total cavopulmonary connection, the modern approach to Fontan, are severely altered from the normal biventricular circulation and may contribute to the long-term complications that are frequently noted. Through recent technological advances, spear-headed by advances in medical imaging, it is now possible to virtually model these surgical procedures and evaluate the patient-specific haemodynamics as part of the pre-operative planning process. This is a novel paradigm with the potential to revolutionise the approach to Fontan surgery, help to optimise the haemodynamic results, and improve patient outcomes. This review provides a brief overview of these methods, presents preliminary results of their clinical usage, and offers insights into its potential future directions.

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Howard, Rachel, Runci Li, Kelly Harvey-Jones, Vinita Verma, Frédéric Lange, Geraldine Boylan, Ilias Tachtsidis i Subhabrata Mitra. "Optical Monitoring in Neonatal Seizures". Cells 11, nr 16 (21.08.2022): 2602. http://dx.doi.org/10.3390/cells11162602.

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Background: Neonatal seizures remain a significant cause of morbidity and mortality worldwide. The past decade has resulted in substantial progress in seizure detection and understanding the impact seizures have on the developing brain. Optical monitoring such as cerebral near-infrared spectroscopy (NIRS) and broadband NIRS can provide non-invasive continuous real-time monitoring of the changes in brain metabolism and haemodynamics. Aim: To perform a systematic review of optical biomarkers to identify changes in cerebral haemodynamics and metabolism during the pre-ictal, ictal, and post-ictal phases of neonatal seizures. Method: A systematic search was performed in eight databases. The search combined the three broad categories: (neonates) AND (NIRS) AND (seizures) using the stepwise approach following PRISMA guidance. Results: Fifteen papers described the haemodynamic and/or metabolic changes observed with NIRS during neonatal seizures. No randomised controlled trials were identified during the search. Studies reported various changes occurring in the pre-ictal, ictal, and post-ictal phases of seizures. Conclusion: Clear changes in cerebral haemodynamics and metabolism were noted during the pre-ictal, ictal, and post-ictal phases of seizures in neonates. Further studies are necessary to determine whether NIRS-based methods can be used at the cot-side to provide clear pathophysiological data in real-time during neonatal seizures.

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Iwao, T., K. Oho, R. Nakano, M. Yamawaki, T. Sakai, M. Sato, Y. Miyamoto, A. Toyonaga i K. Tanikawa. "Effect of meal induced splanchnic arterial vasodilatation on renal arterial haemodynamics in normal subjects and patients with cirrhosis". Gut 43, nr 6 (1.12.1998): 843–48. http://dx.doi.org/10.1136/gut.43.6.843.

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Aims—To investigate the relation between changes in splanchnic arterial haemodynamics and renal arterial haemodynamics in controls and patients with cirrhosis.Methods—Superior mesenteric artery pulsatility index (SMA-PI) and renal artery pulsatility index (R-PI) were measured using Doppler ultrasonography in 24 controls and 36 patients with cirrhosis. These measurements were repeated 30 minutes after ingestion of a liquid meal or placebo. Sixteen controls and 24 patients received the meal, and eight controls and 12 patients received placebo.Results—In the fasting condition, patients with cirrhosis had a lower SMA-PI (p<0.01) and a greater R-PI (p<0.01) compared with controls. Placebo ingestion had no effect on splanchnic and renal haemodynamics. In contrast, ingestion of the meal caused a notable reduction in SMA-PI (p<0.01, p<0.01) and an increase in R-PI (p<0.01, p<0.01) in controls and patients with cirrhosis. The meal induced haemodynamic change in SMA-PI was inversely correlated with that in R-PI in controls (t=−0.42, p<0.05) and in patients with cirrhosis (t=−0.29, p<0.05).Conclusions—Results support the hypothesis that renal arterial vasoconstriction seen in patients with cirrhosis is one of the kidney’s homoeostatic responses to underfilling of the splanchnic arterial circulation.

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Farsetti, D., D. Lo Presti, I. Pisani, G. M. Tiralongo, G. Gagliardi, B. Vasapollo, G. P. Novelli i H. Valensise. "G1. Maternal haemodynamics assessment in preterm delivery: two different haemodynamic profiles". Journal of Maternal-Fetal & Neonatal Medicine 29, sup2 (12.08.2016): 31. http://dx.doi.org/10.1080/14767058.2016.1234791.

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Zeder, Katarina, Horst Olschewski i Gabor Kovacs. "Updated definition of exercise pulmonary hypertension". Breathe 18, nr 4 (grudzień 2022): 220232. http://dx.doi.org/10.1183/20734735.0232-2022.

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In the recently published European Society of Cardiology/European Respiratory Society guidelines on the diagnosis and treatment of pulmonary hypertension (PH) the haemodynamic definitions of PH were updated and a new definition for exercise PH was introduced. Accordingly, exercise PH is characterised by a mean pulmonary arterial pressure/cardiac output (CO) slope >3 Wood units (WU) from rest to exercise. This threshold is supported by several studies demonstrating prognostic and diagnostic relevance of exercise haemodynamics in various patient cohorts. From a differential diagnostic point of view, an elevated pulmonary arterial wedge pressure/CO slope >2 WU may be suitable to identify post-capillary causes of exercise PH. Right heart catheterisation remains the gold standard to assess pulmonary haemodynamics both at rest and exercise. In this review, we discuss the evidence that led to the reintroduction of exercise PH in the PH definitions.

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BELLARD, Elisabeth, Jacques-Olivier FORTRAT, Daniel SCHANG, Jean-Marc DUPUIS, Jacques VICTOR i Georges LEFTHÉRIOTIS. "Changes in the transthoracic impedance signal predict the outcome of a 70° head-up tilt test". Clinical Science 104, nr 2 (14.01.2003): 119–26. http://dx.doi.org/10.1042/cs1040119.

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We determined whether early changes in central haemodynamics, as determined by transthoracic impedance, induced by a 70° head-up tilt (HUT) test could predict syncope. Heart rate, arterial blood pressure and central haemodynamics [pre-ejection period and rapid left ventricular ejection time (T1), slow ejection time (T2) and dZ/dtmax (where Z is thoracic impedance), assessed by the transthoracic impedance technique], were recorded during supine rest and during a 45min 70° HUT test in 68 patients (40±2 years) with a history of unexplained recurrent syncope. We found that 38 patients (42±3 years) had a symptomatic outcome to 70° HUT (fainters) and 30 (39±2 years) had a negative outcome (non-fainters). When measured between 5 and 10min of 70° HUT, T2 had increased significantly only in the fainters, and a change in T2 of >40ms from baseline predicted a positive outcome with a sensitivity of 68% and a specificity of 70%. During supine rest prior to 70° HUT, the fainters exhibited a shorter T2 than non-fainters (183±10 compared with 233±14ms; P<0.01), and a T2 of <199ms predicted a positive outcome to 70° HUT with a sensitivity of 68% and a specificity of 63%. Incorporation of the changes that occurred from rest to 70° HUT in other haemodynamic variables (heart rate >11 beats/min, systolic pressure <2 mmHg, diastolic pressure <7 mmHg and pulse pressure <-3 mmHg) increased the specificity to 97% and the positive predictive value to 93%. Thus transthoracic impedance could detect differences in central haemodynamics between fainters and non-fainters during supine rest and during the initial period of 70° HUT with a consistent sensitivity and specificity when combined with peripheral haemodynamic variables.

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Fronek, A., M. Goldman i K. Fronek. "The Effect of Compression on Venous Haemodynamics Assessed by Quantitative Photoplethysmography". Phlebology: The Journal of Venous Disease 13, nr 3 (wrzesień 1998): 98–101. http://dx.doi.org/10.1177/026835559801300303.

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Background: The purpose of this study was to examine quantitatively the effect of compression stockings on venous haemodynamics at the level of the ankle. Methods: To obtain quantifiable results, a computer-controlled photoplethysmographic system was used to measure the displacement of local blood volume induced by exercise (exercise displacement volume, EDV) and by tilting the subject (tilt displacement volume, TDV). The test was repeated after application of class I compression stockings 20–30 mmHg). The ratio EDV/TDV is considered to represent the efficiency of the veno-muscular pump. Three groups of subjects were studied: a control group ( n = 8), patients with telangiectases ( n = 10) and a group with large varices ( n = 11). Results: The application of external compression had a quantifiable and beneficial effect on venous haemodynamics and was most significantly documented by an increase in veno-muscular efficiency (EDV/TDV) from 28% to 44% in the varicose vein patients. Statistically significant increases of EDV/TDV could also be identified in the telangiectatic patients and normal subjects. EDV also showed an increase with compression stockings; however, statistical significance was only reached in the varicose vein group. Conclusion: External compression (class 1 compression stockings) significantly improved venous haemodynamic indices, especially in patients with varicose veins. Quantitative photoplethysmography used in this study permits a fast, non-invasive and quantifiable evaluation of venous haemodynamics of the lower extremities.

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Oliveira, Rudolf K. F., Manyoo Agarwal, Julie A. Tracy, Abbey L. Karin, Alexander R. Opotowsky, Aaron B. Waxman i David M. Systrom. "Age-related upper limits of normal for maximum upright exercise pulmonary haemodynamics". European Respiratory Journal 47, nr 4 (17.12.2015): 1179–88. http://dx.doi.org/10.1183/13993003.01307-2015.

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The exercise definition of pulmonary hypertension was eliminated from the pulmonary hypertension guidelines in part due to uncertainty of the upper limits of normal (ULNs) for exercise haemodynamics in subjects >50 years old.The present study, therefore, evaluated the pulmonary haemodynamic responses to maximum upright incremental cycling exercise in consecutive subjects who underwent an invasive cardiopulmonary exercise testing for unexplained exertional intolerance, deemed normal based on preserved exercise capacity and normal resting supine haemodynamics. Subjects aged >50 years old (n=41) were compared with subjects ≤50 years old (n=25). ULNs were calculated as mean+2sd.Peak exercise mean pulmonary arterial pressure was not different for subjects >50 and ≤50 years old (23±5 versus 22±4 mmHg, p=0.22), with ULN of 33 and 30 mmHg, respectively. Peak cardiac output was lower in older subjects (median (interquartile range): 12.1 (9.4–14.2) versus 16.2 (13.8–19.2) L·min−1, p<0.001). Peak pulmonary vascular resistance was higher in older subjects compared with younger subjects (mean±sd: 1.20±0.45 versus 0.82±0.26 Wood units, p<0.001), with ULN of 2.10 and 1.34 Wood units, respectively.We observed that subjects >50 and ≤50 years old have different pulmonary vascular responses to exercise. Older subjects have higher pulmonary vascular resistance at peak exercise, resulting in different exercise haemodynamics ULNs compared with the younger population.

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Schobel, Hans P., i Roland E. Schmieder. "Haemodynamics in hypertension". Baillière's Clinical Anaesthesiology 11, nr 4 (grudzień 1997): 623–37. http://dx.doi.org/10.1016/s0950-3501(97)80045-1.

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Woods, H. Feidhlim. "Icodextrin and haemodynamics". Nephrology Dialysis Transplantation 21, nr 3 (7.12.2005): 820. http://dx.doi.org/10.1093/ndt/gfi261.

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Chantelau, Volaco i Meyer-Schwickerath. "New insights into the pathogenesis of diabetic retinopathy – hormonal rather than metabolic factors are important". Vasa 33, nr 4 (1.11.2004): 205–10. http://dx.doi.org/10.1024/0301-1526.33.4.205.

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Diabetic retinopathy has traditionally been viewed as a metabolite-driven, occlusive vasculopathy that affects both retinal microvascular haemodynamics and structure; analogies to cholesterol-driven occlusive atherosclerosis of the macrovascular circulation were drawn. However, this paradigm may no longer be appropriate. Recent evidence suggests that diabetic retinopathy from the beginning is the consequence of a complex hormonal dysfunction, which is related to insulin-dependent up- and downregulation of growth factors, to which metabolic, haemodynamic, endocrine, paracrine, and autocrine mechanisms contribute.

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Jovic, M., Zoran Popovic, Dusko Nezic, V. Ilic, Sinisa Gradinac, M. Babic, A. Kenkovski i Bosko Radomir. "Uloga Swan-Ganz PA katetera u proceni hemodinamskih promena tokom hirurske revaskularizacije miokarda u bolesnika sa oslabljenom funkcijom leve komore". Acta chirurgica Iugoslavica 49, nr 1 (2002): 27–35. http://dx.doi.org/10.2298/aci0201027j.

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Coronary artery bypass surgery in patient with bad left ventricular function is a challenge for surgical time. Specially important is monitoring of haemodynamics. We performed this open, prospective, randomized study with the aim to assess haemodynamics and oxygen profile monitoring. 34 pts for coronary surgery (EF < 40%) were divided in two groups. Group A, 17 pts. Received glucose-insulin-potassium (GIK) solution. Group B, 127 pts. Received Ringer solution. Haemodynamic and oxygen metabolism parameters were measured in four time points. I after the induction in anesthesia; II after the operation; III 6 hours post op.; IV 24 hour post op. Data are expressed as mean +/-SD, ANOVA for repeated measures followed by Newman-Keuls testing were used. In both groups were evident deterioration of cardiac function during first 6h as well as VO2 and DO:, more prominent in Group B. Significant recovery and improvement of cardiac function were evident in Group A after 24 h. CI during the time in Group A improves significantly (2.14+/-0.36 v. 3.05+/-0.55; p=0.0002) and difference during the time between groups was p=0,005. LVSWI improved significantly during the time him Group A (AIII vs. AIV) p=0.007. Simultaneously. VO improves significantly in Group A (103+/-21 vs. 164+/-30, p=0.00001) while difference between groups in DO was p=0.037. Importance of oxygen metabolism monitoring for both, left ventricular function and haemodynamics assessment was evident in our study.

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PECHÈRE-BERTSCHI, Antoinette, Marc MAILLARD, Hans STALDER, Hans R. BRUNNER i Michel BURNIER. "Blood pressure and renal haemodynamic response to salt during the normal menstrual cycle". Clinical Science 98, nr 6 (10.05.2000): 697–702. http://dx.doi.org/10.1042/cs0980697.

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The purpose of the present study was to evaluate prospectively blood pressure and the renal haemodynamic response to salt during the normal menstrual cycle. A total of 35 healthy normotensive young women not on oral contraceptives were enrolled; 17 were studied in the follicular phase and 18 in the luteal phase of the menstrual cycle. The women in each group were then randomly allocated to receive a low-sodium (40 mmol/day) or a high-sodium (250 mmol/day) diet for a 7-day period in two consecutive menstrual cycles. At the end of each dietary period, 24 h ambulatory blood pressure, urinary sodium excretion, plasma renin activity, plasma catecholamine levels and renal haemodynamics were measured. Our results show that the blood pressure response to salt is comparable during the luteal and the follicular phases of the normal menstrual cycle and is characterized by a salt-resistant pattern. In the kidney, effective renal plasma flow was significantly greater and the filtration fraction lower (P < 0.05) after salt loading in women studied in the luteal phase compared with women investigated in the follicular phase. This study thus demonstrates that the female hormone status does not affect the blood pressure response to sodium in young normotensive women. However, in contrast with systemic haemodynamics, the renal response to salt varies during the normal menstrual cycle, suggesting that female sex hormones play a role (direct or indirect) in the regulation of renal haemodynamics.

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Weatherald, Jason, Athénaïs Boucly, David Launay, Vincent Cottin, Grégoire Prévot, Delphine Bourlier, Claire Dauphin i in. "Haemodynamics and serial risk assessment in systemic sclerosis associated pulmonary arterial hypertension". European Respiratory Journal 52, nr 4 (12.09.2018): 1800678. http://dx.doi.org/10.1183/13993003.00678-2018.

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The prognostic importance of follow-up haemodynamics and the validity of multidimensional risk assessment are not well established for systemic sclerosis (SSc)-associated pulmonary arterial hypertension (PAH).We assessed incident SSc-PAH patients to determine the association between clinical and haemodynamic variables at baseline and first follow-up right heart catheterisation (RHC) with transplant-free survival. RHC variables included cardiac index, stroke volume index (SVI), pulmonary arterial compliance and pulmonary vascular resistance. Risk assessment was performed according to the number of low-risk criteria: functional class I or II, 6-min walking distance (6MWD) >440 m, right atrial pressure <8 mmHg and cardiac index ≥2.5 L·min−1·m−2.Transplant-free survival from diagnosis (n=513) was 87%, 55% and 35% at 1, 3 and 5 years, respectively. At baseline, 6MWD was the only independent predictor. A follow-up RHC was available for 353 patients (median interval 4.6 months, interquartile range 3.9–6.4 months). The 6MWD, functional class, cardiac index, SVI, pulmonary arterial compliance and pulmonary vascular resistance were independently associated with transplant-free survival at follow-up, with SVI performing better than other haemodynamic variables. 1-year outcomes were better with increasing number of low-risk criteria at baseline (area under the curve (AUC) 0.63, 95% CI 0.56–0.69) and at first follow-up (AUC 0.71, 95% CI 0.64–0.78).Follow-up haemodynamics and multidimensional risk assessment had greater prognostic significance than at baseline in SSc-PAH.

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Makarov, R. A., S. V. Kinzhalova i N. S. Davydova. "Autoregulation hemodynamics in pregnancies complicated by hypertensive disorders". Systemic Hypertension 12, nr 2 (15.06.2015): 19–23. http://dx.doi.org/10.26442/sg29063.

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In the article the comparative analysis parametres of haemodynamics and features of autoregulation of haemodynamics in patients with uncomplicated pregnancy and pregnancy with hypertension is carried out.Complex investigation of central haemodynamics in 196 patients in the third trimester of pregnancy (65 - with physiologically proceeding pregnancy, 66 - with chronic arterial hypertensia, 65 patients with the pregnancy complicated by preeclampsia) by means of noninvasive bioimpedance technology with calculation of oscillatory activity and the spectral analysis of the three parametres of haemodynamics was carried.Authentic differences of parameters of central haemodynamics and the data of the spectral analysis between healthy pregnant women and pregnant women with hypertensive the disorders were received, the most expressed deviations are noted in preeclampsia.Considering compromised haemodynamics regulation in patients with preeclampsia the differentiated approach to therapy and choice of anesthesiological protection is required at operative delivery in this group of pregnant women.

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Blanchart, A., N. Hernando, D. Fernández-Muñoz, L. Hernando i J. M. López-Novoa. "Lack of effect of indomethacin on systemic and splanchnic haemodynamics in portal hypertensive rats". Clinical Science 68, nr 5 (1.05.1985): 605–7. http://dx.doi.org/10.1042/cs0680605.

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1. Portal hypertension was produced experimentally in rats by partial constriction of the portal vein. 2. Twelve rats were injected daily with indomethacin, 4 mg/kg body weight, and 12 with the vehicle (80% ethanol, 0.5 ml/day). 3. There were no differences in portal-systemic shunts nor systemic or splanchnic haemodynamics between indomethacin-treated and untreated rats. 4. These results suggest that cyclo-oxygenase products do not play a significative role in haemodynamic alterations shown by portal-ligated rats.

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Göbel, Hartmut, Horst Klostermann, Volker Lindner i Sabine Schenkl. "Changes in Cerebral Haemodynamics in Cases of Post-Lumbar Puncture Headache: A Prospective Transcranial Doppler Ultrasound Study". Cephalalgia 10, nr 3 (czerwiec 1990): 117–22. http://dx.doi.org/10.1046/j.1468-2982.1990.1003117.x.

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We used transcranial Doppler ultrasonography in 45 patients to investigate if changes in haemodynamics in the major arteries of the brain base occurred after lumbar puncture and whether or not patients with or without post-lumbar puncture headache differ with respect to their cerebral haemodynamic parameters before and after lumbar puncture. Before lumbar puncture, patients with post-lumbar puncture headache differed from patients without post-lumbar puncture headache in that they showed significantly higher flow velocities and significant asymmetry of flow velocities with lateralization to the right ( p £ 0.05). Patients without post-lumbar puncture headache, on the other hand, showed non-significant flow velocity lateralization to the left. Forty-eight hours after lumbar puncture, both groups demonstrated symmetrical flow velocities. In addition, only patients with post-lumbar puncture headache showed a significant reduction in the flow velocity of the right middle cerebral artery ( p £ 0.05). These findings suggest that it is not only absolute flow velocity that plays a part in the event of headache, the interhemispheric relation of cerebral haemodynamics also plays a fundamental role.

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Geraghty, J. G., W. J. Angerson i D. C. Carter. "Splanchnic Haemodynamics and Vasoactive Agents in Experimental Cirrhosis". HPB Surgery 8, nr 2 (1.01.1994): 83–88. http://dx.doi.org/10.1155/1994/52975.

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It is well known that portal hypertension is associated with a hyperdynamic systemic circulatory state. This study measures systemic and splanchnic haemodynamics in an experimental rat model of hepatic cirrhosis. It also investigates the association between haemodynamic changes in cirrhotic animals and circulating levels of the vasoactive hormones glucagon and vasoactive intestinal polypeptide (VIP). Splanchnic blood flow was significantly increased in the cirrhotic group (13.2 ± 1.3 vs. 9.2 ± 1.6 ml/min, P < 0.05). Circulating levels of glucagon and VIP were two and five fold increased respectively in cirrhotic animals compared to controls. There was a strong correlation between portal pressure and glucagon levels in the cirrhotic group (r = 0.85). Raised splanchnic blood flow is partly responsible for elevated portal pressure in this model and this rise may be humorally mediated.

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Alsagaff, Mochamad Yusuf, Dwi Fachrul Octafian Hidayat i Hiroyuki Daida. "Simultaneous kissing stents in acute left main total occlusion complicated with cardiogenic shock". BMJ Case Reports 14, nr 4 (kwiecień 2021): e241245. http://dx.doi.org/10.1136/bcr-2020-241245.

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We present a case of acute left main bifurcation lesion presenting as very high-risk non-ST elevation acute coronary syndrome. Consequently, an immediate invasive strategy for this complex anatomical lesion in an unstable patient requires an emergent bailout strategy to restore the haemodynamic condition.Our case shows the simultaneous kissing stents technique in a patient with a true left main bifurcation lesion (Medina 1-1-1) as a strategy to overcome the compromised haemodynamics. This protocol would be an alternative life-saving strategy in an acute setting.

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Ströhn, A., H. M. Häfner i M. Jünger. "Biophysical characteristics of medical compression stockings". Phlebologie 36, nr 04 (2007): 197–204. http://dx.doi.org/10.1055/s-0037-1622183.

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Summary Aim: Haemodynamic effectivity of 13 compression stockings in correlation with its physical characteristics. Patients, methods: In a prospective study, 42 patients in clinical stage C1–4 were examined with dynamic mercury strain gauge plethysmography to determine the effects of 13 different compression stockings in compression classes 2 and 3 (CEN) on venous haemodynamics. At the same time that venous function measurement was monitored, the pressure exerted by the compression stockings was measured under resting conditions and during standardized exercises by the patients. Results: Resting pressure measured while the patient was reclining corresponded to the in vitro textile data for the corresponding compression class in all of the stockings. The compression stockings improved venous refill times t0 and t1/2 to a statistically significant degree. The differences in the improvement in refill times t0 and t1/2 was found to depend on the quotient of maximum working pressure during movement over resting pressure (pW/pR) while standing (r = 0.90, p < 0.01 ). The improvement of the expelled volume correlated with decrease of resting pressure from ankle to calf (r = 0.86, p <0.01 ). Conclusion: Compression stockings that exert the same resting pressure at ankle level in reclining patients can still have different effects on venous haemodynamics. The haemodynamic effectivity of the various compression materials is determined above all by the degree of stiffness, which can be characterized in vivo as the ratio of maximum working pressure to resting pressure (pW/pR) while standing.

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Boucly, Athénaïs, Vincent Cottin, Hilario Nunes, Xavier Jaïs, Abdelatif Tazi, Grégoire Prévôt, Martine Reynaud-Gaubert i in. "Management and long-term outcomes of sarcoidosis-associated pulmonary hypertension". European Respiratory Journal 50, nr 4 (październik 2017): 1700465. http://dx.doi.org/10.1183/13993003.00465-2017.

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Studies reporting the effects of modern strategies with pulmonary arterial hypertension (PAH)-targeted therapies in sarcoidosis-associated pulmonary hypertension (S-APH) are limited.Clinical and haemodynamic data from newly diagnosed patients with severe S-APH (mean pulmonary artery pressure (mPAP) >35 mmHg or mPAP 25–35 mmHg with cardiac index <2.5 L·min−1·m−2) were collected from the French Pulmonary Hypertension Registry between 2004 and 2015.Data from 126 patients with severe S-APH were analysed (mean±sd age 57.5±11.6 years, 74% radiological stage IV). 97 patients (77%) received PAH-targeted therapy and immunosuppressive therapy was initiated or escalated in 33 patients at the time of pulmonary hypertension diagnosis. Four months after PAH-targeted therapy initiation, mean±sd pulmonary vascular resistance decreased from 9.7±4.4 to 6.9±3.0 Wood units (p<0.001), without significant improvement in exercise capacity. Among the 11 patients treated only with immunosuppressive therapy, a haemodynamic improvement was observed in four patients, including two with compressive lymph nodes. After a median follow-up of 28 months, 39 patients needed PAH-targeted therapy escalation, nine underwent lung transplantation and 42 had died. Survival at 1, 3 and 5 years was 93%, 74% and 55%, respectively.PAH-targeted therapy improved short-term pulmonary haemodynamics in severe S-APH without change in exercise capacity. Immunosuppressive therapy improved haemodynamics in selected patients. Pulmonary hypertension in sarcoidosis remains associated with a poor prognosis.

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Vermeulen, Marijn J., Romy Gaillard, Kozeta Miliku, Irwin Reiss, Eric A. P. Steegers, Vincent Jaddoe i Janine Felix. "Influence of genetic variants for birth weight on fetal growth and placental haemodynamics". Archives of Disease in Childhood - Fetal and Neonatal Edition 105, nr 4 (30.10.2019): 393–98. http://dx.doi.org/10.1136/archdischild-2019-317044.

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ObjectiveTo determine the combined effect of 60 genetic variants (single nucleotide polymorphisms, SNPs), previously identified as being associated with birth weight, on fetal growth and placental haemodynamics throughout pregnancy.DesignProspective birth cohort (Generation R Study).SettingGeneral multiethnic population.Participants5374 singleton liveborn children with genome-wide association arrays and fetal growth data.MethodsLongitudinal and cross-sectional analyses of a genetic score of the total number of birth weight–increasing alleles across the 59 available SNPs and repeated fetal growth and haemodynamic measures.Main outcome measuresSD scores (SDS) of fetal weight, (femur) length, head circumference, umbilical artery pulsatility index, uterine artery mean resistance index and placental weight, in different periods of pregnancy until birth.ResultsIn longitudinal analyses, the effect of the genetic score on the fetal growth measures increased throughout pregnancy (p<0.001). At 20 weeks of gestation, the genetic score was not associated with any of the fetal growth measures, whereas at 30 weeks it was associated with all. The strongest effects were observed at birth: per SD increase in genetic score, birth weight increased by 0.15 SDS (95% confidence interval: 0.13 to 0.18), birth length by 0.12 SDS (0.08 to 0.19) and head circumference by 0.08 SDS (0.05 to 0.12). The genetic score was not associated with placental haemodynamics, but was associated with a 14 g (10 to 18) increase in placental weight per SDS increase in genetic score.ConclusionsOur results suggest that genetic variants related to birth weight exert their combined effect on fetal growth from second half of pregnancy onwards and have no effect on placental haemodynamics.

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Zegelbone, Phillip M., Richard E. Ringel, John D. Coulson, Melanie K. Nies, Meagan E. Stabler, Jeremiah R. Brown i Allen D. Everett. "Heart failure biomarker levels correlate with invasive haemodynamics in pulmonary valve replacement". Cardiology in the Young 30, nr 1 (27.11.2019): 50–54. http://dx.doi.org/10.1017/s1047951119002737.

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AbstractBackground:Although widely used in cardiology, relation of heart failure biomarkers to cardiac haemodynamics in patients with CHD (and in particular with pulmonary insufficiency undergoing pulmonary valve replacement) remains unclear. We hypothesised that the cardiac function biomarkers N-terminal pro-brain natriuretic peptide (NT-proBNP), soluble suppressor of tumorigenicity 2, and galectin-3 would have significant associations to right ventricular haemodynamic derangements.Methods:Consecutive patients ( n = 16) undergoing cardiac catheterisation for transcatheter pulmonary valve replacement were studied. NT-proBNP, soluble suppressor of tumorigenicity 2, and galectin-3 levels were measured using a multiplex enzyme-linked immunosorbent assay from a pre-intervention blood sample obtained after sheath placement. Spearman correlation was used to identify significant correlations (p ≤ 0.05) of biomarkers with baseline cardiac haemodynamics. Cardiac MRI data (indexed right ventricular and left ventricular end-diastolic volumes and ejection fraction) prior to device placement were also compared to biomarker levels.Results:NT-proBNP and soluble suppressor of tumorigenicity 2 were significantly correlated (p < 0.01) with baseline mean right atrial pressure and right ventricular end-diastolic pressure. Only NT-proBNP was significantly correlated with age. Galectin-3 did not have significant associations in this cohort. Cardiac MRI measures of right ventricular function and volume were not correlated to biomarker levels or right heart haemodynamics.Conclusions:NT-proBNP and soluble suppressor of tumorigenicity 2, biomarkers of myocardial strain, significantly correlated to invasive pressure haemodynamics in transcatheter pulmonary valve replacement patients. Serial determination of soluble suppressor of tumorigenicity 2, as it was not associated with age, may be superior to serial measurement of NT-proBNP as an indicator for timing of pulmonary valve replacement.

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Koltukluoğlu, Taha S., i Pablo J. Blanco. "Boundary control in computational haemodynamics". Journal of Fluid Mechanics 847 (21.05.2018): 329–64. http://dx.doi.org/10.1017/jfm.2018.329.

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In this work, a data assimilation method is proposed following an optimise-then-discretise approach, and is applied in the context of computational haemodynamics. The methodology aims to make use of phase-contrast magnetic resonance imaging to perform optimal flow control in computational fluid dynamic simulations. Flow matching between observations and model predictions is performed in luminal regions, excluding near-wall areas, improving the near-wall flow reconstruction to enhance the estimation of related quantities such as wall shear stresses. The proposed approach remarkably improves the flow field at the aortic root and reveals a great potential for predicting clinically relevant haemodynamic phenomenology. This work presents model validation against an analytical solution using the standard 3-D Hagen–Poiseuille flow, and validation with real data involving the flow control problem in a glass replica of a human aorta imaged with a 3T magnetic resonance scanner. In vitro experiments consist of both a numerically generated reference flow solution, which is considered as the ground truth, as well as real flow MRI data obtained from phase-contrast flow acquisitions. The validation against the in vitro flow MRI experiments is performed for different flow regimes and model parameters including different mesh refinements.

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McClarty, Davis, Maral Ouzounian, Mingyi Tang, Daniella Eliathamby, David Romero, Elsie Nguyen, Craig A. Simmons, Cristina Amon i Jennifer Chia-Ying Chung. "Ascending aortic aneurysm haemodynamics are associated with aortic wall biomechanical properties". European Journal of Cardio-Thoracic Surgery 61, nr 2 (29.10.2021): 367–75. http://dx.doi.org/10.1093/ejcts/ezab471.

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Abstract OBJECTIVES The effect of aortic haemodynamics on arterial wall properties in ascending thoracic aortic aneurysms (ATAAs) is not well understood. We aim to delineate the relationship between shear forces along the aortic wall and loco-regional biomechanical properties associated with the risk of aortic dissection. METHODS Five patients with ATAA underwent preoperative magnetic resonance angiogram and four-dimensional magnetic resonance imaging. From these scans, haemodynamic models were constructed to estimate maximum wall shear stress (WSS), maximum time-averaged WSS, average oscillating shear index and average relative residence time. Fourteen resected aortic samples from these patients underwent bi-axial tensile testing to determine energy loss (ΔUL) and elastic modulus (E10) in the longitudinal (ΔULlong, E10long) and circumferential (ΔULcirc, E10circ) directions and the anisotropic index (AI) for each parameter. Nine resected aortic samples underwent peel testing to determine the delamination strength (Sd). Haemodynamic indices were then correlated to the biomechanical properties. RESULTS A positive correlation was found between maximum WSS and ΔULlong rs=0.75, P = 0.002 and AIΔUL (rs=0.68, P=0.01). Increasing maximum time-averaged WSS was found to be associated with increasing ΔULlong (rs=0.73, P = 0.003) and AIΔUL (rs=0.62, P=0.02). Average oscillating shear index positively correlated with Sd (rs=0.73,P=0.04). No significant relationship was found between any haemodynamic index and E10, or between relative residence time and any biomechanical property. CONCLUSIONS Shear forces at the wall of ATAAs are associated with local degradation of arterial wall viscoelastic hysteresis (ΔUL) and delamination strength, a surrogate for aortic dissection. Haemodynamic indices may provide insights into aortic wall integrity, ultimately leading to novel metrics for assessing risks associated with ATAAs.

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Wang, Hui, Hongyang Li, Xiaojie Zhang, Lanyan Qiu, Zhenchang Wang i Yanling Wang. "Ocular Image and Haemodynamic Features Associated with Different Gradings of Ipsilateral Internal Carotid Artery Stenosis". Journal of Ophthalmology 2017 (2017): 1–10. http://dx.doi.org/10.1155/2017/1842176.

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Objectives. To analyse the changes of ocular haemodynamics and morphology in Chinese patients with internal carotid artery (ICA) stenosis in the current study. Methods. A retrospective case-control study was conducted with 219 patients. The haemodynamic characteristics, the calibre of retinal vessels, and the subfoveal choroidal thickness (SFChT) were compared. We analysed the correlations with the degree of ipsilateral ICA stenosis. Results. There were no significant differences among the groups in the central retinal artery equivalent (CRAE), central retinal vein equivalent (CRVE), and AVR (p=0.073, p=0.188, and p=0.738, resp.). The peak systolic velocity (PSV) and end diastolic velocity (EDV) in the central retinal artery (CRA) and the posterior ciliary artery (PCA) were significantly lower than normal eyes (p<0.001). The outer retinal layer thickness and SFChT values of the ICA stenosis groups were significantly lower than normal eyes (p=0.030 and p<0.001, resp.). Conclusion. The PSV and EDV in CRA and PCA and the SFChT and outer retinal layer thickness of ICA eyes were significantly lower than normal eyes. ICA stenosis may impact choroidal haemodynamics, and decreased choroidal circulation might affect the discordance of the SFChT and the outer retinal layer thickness.

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Banik, Sujoy, Pallav Kumar, Hemanshu Prabhakar i Gyaninder Singh. "Dexmedetomidine and propofol for cerebral angiography in non-intubated patients: A comparative study". Journal of Neuroanaesthesiology and Critical Care 02, nr 02 (sierpień 2015): 121–26. http://dx.doi.org/10.4103/2348-0548.155463.

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Abstract Context: Patients posted for cerebral angiography may be restless and drowsy with high chance of inadvertent movements. Aims: The primary objective was to compare the incidence of inadvertent movements between propofol and dexmedetomidine groups. The secondary objectives include comparison of recovery time and characteristics, Steward’s score, and haemodynamic and respiratory parameters between the two groups. Settings and Design: Prospective, randomised, double-blind, pilot study. Materials and Methods: In all, 20 adult uncooperative, drowsy patients were randomised to dexmedetomidine (1 μg/kg bolus over 10 minutes followed by 0.3-0.7 μg/kg/hour infusion) or propofol (100 μg/kg/min for 10 minutes followed by 25-75 μg/kg/min infusion). Rate of movement, success of sedation, haemodynamics, respiratory parameters, Steward’s recovery score and recovery time were recorded. Statistical analysis used: Repeated measures of analysis of variance, Mann-Whitney test, independent and paired t-tests, and Fisher test. Results: The median rate of movement was similar (1, P = 0.206) with success of sedation achieved in 7 (70%) patients in Group D and 9 (90%) patients in Group P, which was comparable (P = 0.582). The median recovery time in patients in Group D was 150 (37–764) seconds and in Group P was 128 (54–174) seconds (P = 0.519) with similar Steward’s scores (P = 0.363). Haemodynamics and respiratory variables were well-maintained during loading and maintenance dose infusions in both the groups. Conclusions: Dexmedetomidine is a safe alternative for diagnostic cerebral angiography. Its success of sedation, median rate of movement during the imaging procedure, haemodynamics, respiratory parameters, recovery time and Steward’s recovery score were similar to propofol in our study.

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Saiki, Hirofumi, Seiko Kuwata, Yoichi Iwamoto, Hirotaka Ishido, Mio Taketazu, Satoshi Masutani, Takashi Nishida i Hideaki Senzaki. "Fenestration in the Fontan circulation as a strategy for chronic cardioprotection". Heart 105, nr 16 (2.03.2019): 1266–72. http://dx.doi.org/10.1136/heartjnl-2018-314183.

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BackgroundFenestration in the Fontan circulation potentially liberates patients from factors leading to cardiovascular remodelling, through stable haemodynamics with attenuated venous congestion. We hypothesised that a fenestrated Fontan procedure would possess chronic haemodynamic advantages beyond the preload preservation.MethodsWe enrolled 35 patients with fenestrated Fontan with a constructed pressure–volume relationship under dobutamine (DOB) infusion and/or transient fenestration occlusion (TFO). Despite the use of antiplatelets and anticoagulants, natural closure of fenestration was confirmed in 11 patients. Cardiovascular properties in patients with patent fenestration (P-F) were compared with those in patients with naturally closed fenestration (NC-F). To further delineate the roles of fenestration, paired analysis in patients with P-F was performed under DOB or rapid atrial pacing with/without TFO.ResultsAs compared with P-F, patients with NC-F had a higher heart rate (HR), smaller ventricular end-diastolic area, better ejection fraction and higher central venous pressure, with higher pulmonary resistance. While this was similarly observed after DOB infusion, DOB markedly augmented diastolic and systolic ventricular stiffness in patients with NC-F compared with patients with P-F. As a mirror image of the relationship between patients with P-F and NC-F, TFO markedly reduced preload, suppressed cardiac output, and augmented afterload and diastolic stiffness. Importantly, rapid atrial pacing compromised these haemodynamic advantages of fenestration.ConclusionsAs compared with patients with NC-F, patients with P-F had robust haemodynamics with secured preload reserve, reduced afterload and a suppressed beta-adrenergic response, along with a lower HR at baseline, although these advantages had been overshadowed, or worsened, by an increased HR.

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Bistafa, Sylvio R. "Euler, Father of Haemodynamics". Euleriana 1, nr 1 (2.02.2021): 88. http://dx.doi.org/10.56031/2693-9908.1007.

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&NA;. "Haemodynamics of antihypertensives reviewed". Inpharma Weekly &NA;, nr 895 (lipiec 1993): 7. http://dx.doi.org/10.2165/00128413-199308950-00010.

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WEBSTER, N. R., M. C. BELLAMY, J. P. A. LODGE i S. A. SADEK. "Haemodynamics of Liver Reperfusion". Survey of Anesthesiology 38, nr 6 (grudzień 1994): 364. http://dx.doi.org/10.1097/00132586-199412000-00068.

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Patel, A. S., i K. G. Burnand. "Cardiovascular haemodynamics and shock". Surgery (Oxford) 27, nr 11 (listopad 2009): 459–64. http://dx.doi.org/10.1016/j.mpsur.2009.09.009.

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Bawdon, Hannah, i Michael Reay. "Haemodynamics and cardiovascular shock". Surgery (Oxford) 30, nr 10 (październik 2012): 512–17. http://dx.doi.org/10.1016/j.mpsur.2012.07.011.

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Haseeb, Faiuna, i Michael Reay. "Haemodynamics and cardiovascular shock". Surgery (Oxford) 33, nr 10 (październik 2015): 467–73. http://dx.doi.org/10.1016/j.mpsur.2015.07.021.

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Shepherd, Stephen J. "Haemodynamics and cardiovascular shock". Surgery (Oxford) 36, nr 12 (grudzień 2018): 682–87. http://dx.doi.org/10.1016/j.mpsur.2018.09.021.

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Pourcelot, L. "Basic Principles of Haemodynamics". European Journal of Ultrasound 6 (listopad 1997): S6—S7. http://dx.doi.org/10.1016/s0929-8266(97)87204-7.

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