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Cardiac damage caused by radiation in the long term varies according to the radiation dose received by the heart. In this study, it was aimed to evaluate the damage caused by different radiation doses in the heart, together with hemodynamic parameters, immunhistochemistry, and histopathological analyzes for long term. The animals were divided into four groups: The rats in control group (Group 1) were not irradiated; the rats in group 2 were irradiated with 5 Gy; the rats in group 3 were irradiated with 10 Gy and the rats in group 4 were irradiated with 20 Gy. Hemodynamic parameters and indices were determined from the impedance cardiography (ICG) recording in the whole groups before they were irradiated with RT and 180 days after RT. And then, interleukin-1β, interleukin-10, TNF-α, apopthosis were determined in all groups. In addition, histological changes of heart and aorta were evaluated. Histopathologic, cytokine and hemodynamic findings supported that cardiac damage increased with increasing radiation dose. it is important in terms of being an alternative and supportive method to other methods to be able to detect heart diseases caused by RT with the ICG method. [ABSTRACT FROM AUTHOR]

Reducing maternal morbidity and mortality has been a challenge for low and middle-income countries, especially in the setting of hypertensive disorders of pregnancy. Improved strategies for treating obstetric patients with resistant hypertension are needed. We sought to explore whether hemodynamic parameters may be used to identify patients that develop resistant hypertension in pregnancy. Retrospective cohort study among pregnant patients with gestational hypertension or preeclampsia that experienced severe blood pressure elevations. Hemodynamic variables were evaluated, including cardiac output (CO), and total peripheral resistance (TPR). The primary endpoint was resistant hypertension. An exploratory logistic regression was performed to evaluate the association between the hemodynamic profile and the development of resistant hypertension. Adverse maternal and fetal outcomes were additionally described according to the presence of resistant hypertension. Fifty-seven patients with severe pregnancy hypertension were included, of whom 34 developed resistant hypertension (59.7%). The resistant hypertension group, in comparison to those without resistant hypertension, presented with a hypodynamic profile characterized by reduced CO < 5 L/min (41.2% vs. 8.7%, p: 0.007), and increased TPR > 1400 dyn-s/cm5 (64.7% vs. 39.1%, p: 0.057). Logistic regression analysis revealed an association between a hypodynamic profile and resistant hypertension (OR 3.252, 95% CI 1.079–9.804; p = 0.035). Newborns of the resistant hypertension group had more frequent low birth weight (<2500 g), low Apgar scores, ICU admissions, and acute respiratory distress syndrome. Patients experiencing hypertensive crisis during pregnancy and exhibiting a hypodynamic profile (TPR ≥1400 dyn·s/cm5 and CO ≤ 5 L/min) developed higher rates of resistant hypertension. [ABSTRACT FROM AUTHOR]

Cardiac Output (CO) is a significant hemodynamic index for the diagnosis and treatment of cardiovascular diseases. Impedance cardiography (ICG) is one of the non-invasive methods widely investigated for its simplicity, cost-effectiveness and ability to measure cardiac output continuously. However, measured ICG signals are contaminated by the respiratory artefact leading to difficulties in determining characteristic points in the signal waveform, thereby lowering the accuracy of measurement results. Thus, suppressing this artefact plays an important role in ICG signal processing. This paper aims to propose a method of noise filtering to improve the quality of the signal as well as a model to evaluate the noise filtering efficiency of the method. The proposed algorithm showed promising results with the output SNR values of 21.99 ± 3.20 dB, 20.40 ± 2.88 dB, 15.57 ± 4.79 dB for normal breathing, forced breathing, and rapid breathing respectively. The root mean square percentage error (RMSPE) values of the output signals processed by the proposed algorithm compared to the standard ICG signal source for normal breathing, forced breathing, and rapid breathing are 24.13 ± 22.66%, 18.09 ± 12.98%, 32.13 ± 20.40% respectively. The quality-enhanced ICG signal could be effective tool for assisting doctors to detect cardiac abnormalities via evaluating the morphology of ICG signal waveforms as well as improving accuracy in calculating beat-to-beat and averaged hemodynamic parameters. [ABSTRACT FROM AUTHOR]

Measuring and monitoring hemodynamic parameters has brought many benefits in supporting diagnosis and treatment for cardiovascular patients. There are many advantages to measuring hemodynamic parameters by non-invasive technique based on impedance cardiography (ICG) such as simplicity, real-time and low cost. However, the electrode positions of this method are very difficult to implement in cases where the patient has to use multiple medical devices at the same time, especially for patients on active treatment and resuscitation. This paper presents the results of the study proposing new three locations of ICG electrodes to overcome the above limitation. Accordingly, we measured and evaluated 10 volunteers on the Niccomo device. The results show that all three positions of proposed electrode can be used to replace standard electrode position. In particular, the 1st proposed position, can be used to measure all five hemodynamic parameters HR, SV, LVET, Zo, CO and ICG waveforms, expressed by the average correlation and the relative average difference of five parameters, R 2 ¯ = 0.9641 and Mean ¯ = 3.31%. The 2nd proposed position can be used to measure four parameters HR, SV, LVET, CO and ICG waveforms shown by R 2 ¯ = 0.9091 and Mean ¯ = 8.67%. The 3rd proposed position can be used to measure three parameters HR, Zo and LVET, expressed by R 2 ¯ = 0.8485 and Mean ¯ = 9.26%. [ABSTRACT FROM AUTHOR]

Objectives: Functional gastrointestinal (GI) symptoms, such as IBS (irritable bowel syndrome), have been suggested to be associated with autonomic neuropathy. We therefore examined associations between hemodynamic indices of autonomic control, functional GI symptoms and stress in a population-based cohort. Methods and materials: The study included 2094 participants of the Malmö Offspring Study (mean age 40.6 ± 13.8 years, 53.9% women). 509 (24.3%) reported having GI symptoms the last 2 weeks, without having organic GI disease, and 347 subjects (16.6%) reported IBS. Office and ambulatory 24-h systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate were measured. Associations between hemodynamic parameters and abdominal pain, diarrhea, constipation, bloating and flatulence, vomiting and nausea and psychological well-being according to the visual analog scale for IBS (VAS-IBS), and stress, were performed by Spearman's correlation test and linear regression models. Results: Subjects who reported GI symptoms had lower office supine and standing DBP and lower 24 h SBP and DBP compared with those without GI symptoms. Regarding specific symptoms, diarrhea was correlated with 24-h measurements of SBP (rs = 0.197), DBP (rs = 0.173) and heart rate (rs = 0.134). Subjects with the most severe diarrhea had higher 24-h SBP (125.2 vs. 119.0 mmHg; p =.038), DBP (74.0 vs. 69.0 mmHg; p =.033) and heart rate (74.5 vs 71.1 beats/minute; p =.048), after adjustments for confounders, compared to the other. There were no associations between other GI symptoms, IBS, stress and hemodynamic alterations. Conclusion: Functional diarrhea was associated with hemodynamic indices of sympathetic activation, supporting a possible role of the autonomic nervous system in diarrhea. [ABSTRACT FROM AUTHOR]

Objectives: Arterial stiffness has emerged as a surrogate marker of cardiovascular disease. We investigated the role of myocardial performance and hemodynamic parameters in arterial stiffness in patients with rheumatoid arthritis (RA), which is accompanied by excess cardiovascular risk.Design: Arterial stiffness was evaluated with pulse wave velocity (PWV) in RA patients and controls. Cardiac and hemodynamic characterization was based on impedance cardiography. Cardiovascular risk factors, inflammatory markers and disease-related parameters were assessed.Results: PWV (8.2 ± 2.1 vs 7.4 ± 1.4 m/s, p = .016) was higher among RA patients (n = 104) compared to controls (n = 52). In the RA group, PWV correlated with markers of cardiac contractibility (acceleration and velocity index), myocardial blood flow (cardiac output and stroke volume), preload (thoracic fluid content) and afterload (systemic vascular resistance) (p < .05 for all). PWV tended to increase with decreasing oxygen delivery to the myocardium (r = 0.055), as well as with shortening of the ejection duration of the left ventricle (p = .058). However, these associations no longer remained significant after adjustment for classical cardiovascular risk factors, inflammation and corticosteroid use, which were independently associated with PWV.Conclusions: Among patients with RA, arterial stiffness appears as the composite of cardiovascular risk factors and inflammation, while corticosteroid use emerges as an additional adverse factor. [ABSTRACT FROM AUTHOR]

One of the important parts of the cardiac system is aorta which is the fundamental channel and supply of oxygenated blood in the body. Diseases of the aorta represent critical cardiovascular bleakness and mortality around the world. This study aims at investigation of hemodynamic parameters in a two-dimensional axisymmetric model of three-layer grafted aorta using fluid–structure interaction (FSI). It assumes that a damaged part of aorta, which may happen as a result of some diseases like aneurysm, dissection and post-stenotic dilatation, is replaced with a biomaterial graft. Four types of grafts materials so-called Polyurethane, Silicone rubber, Polytetrafluoroethylene (PTFE) and Dacron are considered in the present study. The assumption of linear elastic and isotropic material is set for the both aorta's wall and aforementioned grafts. Blood is considered as an incompressible and Newtonian fluid. The results indicate higher displacement in Polyurethane and silicone rubber in comparison with other two. Furthermore, results reveal that blood flow velocity has slightly higher values in PTFE and Dacron grafted models compared to Polyurethane and Silicone rubber ones. Even though there are some differences in hemodynamic patterns in these grafted models, they are not considerable as much as von Mises stresses across the graft-aorta intersections are. This study shows that the types of material grafts play an important role in the amount of stresses particularly at intersections of aorta and graft. [ABSTRACT FROM PUBLISHER]

Objective. Nitric oxide is an important vasoactive mediator. Changes in NO production, caused by functional variants of both endothelial and inducible NO synthase ( eNOS, iNOS), might play a role in portal hypertension. The aim was to study the significance of functional eNOS and iNOS gene variants in cirrhotic patients and their interrelationship to both inflammatory and endothelial activation parameters. Material and methods. One hundred and thirty-two patients with liver cirrhosis (age 36-72 years) and 101 controls were examined for functional variants of eNOS (E298D, 27bpintr4, 786T/C) and iNOS (R221W, S608L) genes. Inflammatory (IL6, IL8, IL10) and vasoactive (sVCAM-1, E-selectin) cytokines were measured using ELISA kits. Results. The frequency of E298D (GG 12%, GT 41%, TT 47%), 28bpintr4 (AA 6%, AB 28%, BB 66%), 786T/C genotypes (CC 17%, CT 45%, TT 38%), as well as R221W (CC 93%, CT 7%, TT 0%), and S608L (CC 65%, CT 32%, TT 3%) genotypes in cirrhotic patients did not differ from the controls ( p > 0.05 for all comparisons). No relationship was found between the frequency of these genotypes and the severity of portal hypertension, or either inflammatory or vasoactive cytokines. A positive correlation was found between hepatic venous pressure gradient and cytokine concentration: sVCAM-1, IL6, IL8, IL10. Conclusions. Examined eNOS and iNOS variants have no relationship to pathogenesis of liver cirrhosis. Severity of portal hypertension was associated with the changes in endothelial activation. [ABSTRACT FROM AUTHOR]

Hemodynamic parameters using Swan Ganz catheter were studied in 17 patients with end stage renal disease. The acute effects of radiocephalic AV fistula on the hemodynamic parameters were studied at 24 hours of surgery. The chronic effects were studied in 8 of these patients at 6 weeks of arteriovenous(AV) fistula. The AV fistula matured in 3 to 4 weeks time and blood flow was sufficient for hemodialysis(400 mL/min). Patients with chronic renal failure had normal or high normal hemodynamic parameters. Six weeks after the AV fistula, the cardiac index and the stroke volume index slightly increased along with a significant increase in systolic and mean systemic arterial pressure. None of the patients had significant increase in cardiac filling pressures. Although there was some fall in systemic vascular resistance index and rise in cardiac index and stroke volume index, these changes were physically small and unlikely to put any extra hemodynamic load. Thus, AV fistula in dialysis patients is not an appreciable cause of circulatory or pulmonary congestion. [ABSTRACT FROM AUTHOR]