National Repository of Grey Literature 8 records found  Search took 0.01 seconds. 
Remodeling of the intima-media complex of the common carotid artery and left ventricle myocardium in patients with primary and secondary hypertension
Majtan, Bohumil ; Holaj, Robert (advisor) ; Piťha, Jan (referee) ; Danzig, Vilém (referee)
Arterial hypertension ranks among the most prevalent cardiovascular disorders and represents one of the most significant risk factors for cardiovascular morbidity and mortality. Beyond hypertension itself, additional hemodynamic and neuroendocrine influences contribute to the pathological mechanisms that induce structural alterations in the cardiovascular system. Of notable importance in this process is the excessive production of aldosterone and catecholamines. The objective of the research has been to study the impact of aldosterone and catechola- mine excess on intima-media complex remodeling in the common carotid artery and left ventricular wall in primary aldosteronism (PA) and pheochromocytoma (PHEO) patients. Texture analysis of the intima-media complex of the common carotid artery was conducted in 33 PA patients, 52 EH patients, and 33 normotensive individuals. 140 Haralick features and 10 wavelets were analyzed and utilized to train an XGBoost classifier. Additionally, the intima-media thickness (IMT) of the common carotid artery and left ventricular mass index (LVMi) were examined in 50 PHEO patients before and 5 years post- adrenalectomy and compared to 50 EH patients. In differentiating between PA and EH, we achieved a classification accuracy of 73 %, compared to the clinical gold...
Analysis of echocardiographic findings in patients with primary and secondary hypertension using new sophisticated modalities
Kvasnička, Jan ; Holaj, Robert (advisor) ; Wohlfahrt, Peter (referee) ; Danzig, Vilém (referee)
6 Abstract Introduction: Heart damage in essential hypertension (EH) is one of the most serious consequences of high blood pressure. However, in the case of secondary hypertension, multiple pathophysiological effects may apply. For example, pheochromocytomas (PHEOs), which are tumors arising from the chromaffin cells of the adrenal medulla, have the ability to produce, metabolize, and secrete catecholamines. Overproduction of catecholamines leads to cardiac and other impairments by many mechanisms. The aim of our work was to verify this fact and at the same time to investigate whether global longitudinal strain (GLS), measured using speckle tracking echocardiography, can detect this damage earlier and also determine the adjustment of function after adrenalectomy. Methods: We analyzed 17 patients with PHEO and 18 patients with EH with the same hemodynamic parameters. Subsequently, we managed to increase the number of patients with PHEO to 24, and they were also examined 1 year after adrenalectomy. Results: Patients with PFEO did not differ in echocardiographic parameters including left ventricular ejection fraction compared to EH (0.69 ± 0.04 vs. 0.71 ± 0.05; NS), however, they had significantly lower GLS (−14.8 ± 1.5 vs. −17.8 ± 1.7; p < 0.001). One year after adrenalectomy, the GLS parameter improved...
Changes of the electric field of the heart in disorders of glucose metabolism and ways of influencing them by correction of impaired autonomic nervous regulation
Fialová, Elena ; Kittnar, Otomar (advisor) ; Danzig, Vilém (referee) ; Ošťádal, Petr (referee)
Diabetes mellitus (DM) is not just a simple metabolic disorder, however, it is considered to be a cardiovascular disease of a metabolic origin. This is apparent especially when speaking about type 2 diabetes (DM II). Patients with DM have a high occurrence of vegetative nervous system (VNS) disorders that manifest themselves as an increased activity of the sympathetic nervous system that correlates with peripheral autonomic neuropathy and is considered to be the major pathophysiological mechanism for the development of DM II. The objective of our study was to determine whether a comprehensive spa treatment (ST) may affect the level of the sympathetic tone of patients suffering from DM II. As an indicator of the sympathetic tone, selected electrocardiographic parameters derived from the HRV, microvolt T-wave alternans, and microvolt R-wave alternans were evaluated. The electrophysiological examination of patients was performed before and after a three-week spa treatment using the KARDiVAR system. The method is used to examine the current state of the autonomic nervous system and carry out an analysis of risk factors and adaptive capabilities of the organism. The results showed favorable changes in DM II patients after the ST, primarily in terms of reduced sympathetic adrenal system activity,...
The study of new risk factors of the cardiovascular diseases
Eremiášová, Lenka ; Danzig, Vilém (advisor) ; Vrablík, Michal (referee) ; Rosolová, Hana (referee)
Bilirubin is a major product of the heme catabolism in the vascular bed with substantial antioxidant properties. These importantly contribute to pathogenesis of diseases associated with increased oxidative stress, including cardiovascular or cancer diseases. In the first part of this PhD project serum bilirubin concentrations were examined in the 1 % representative sample of the general Czech population, together with determination of the prevalence of Gilbert's syndrome. Bilirubin concentrations were determined also within individual polymorphisms of the UGT1A1 gene (OMIM*191740) responsible for bilirubin biotransformation in the liver, including their association with the basic risk factors for atherosclerosis. We also assessed the activity of the standard liver enzymes (representing another significant risk factor for the development of cardiovascular diseases) with surprisingly high proportion of subjects with elevated values. Simultaneously, we determined the concentrations of serum bilirubin in a group of patients with an acute coronary syndrome, who manifested with significantly lower concentrations as compared to general population. In the second part of this research project, the relationship between plasma concentrations of bilirubin and individual variants of UGT1A1 gene polymorphisms...
Regional flow and number of microembolisms in the common carotid artery at different levels of hemodynamics controlled by VA-ECMO.
Janák, David ; Kittnar, Otomar (advisor) ; Danzig, Vilém (referee) ; Bešík, Josef (referee)
Extracorporeal membrane oxygenation (ECMO) is a method that allows extracorporeal life support in potentially reversible life-threatening conditions affecting the heart or lungs which are refractory to conventional treatment. Depending on the parameters of its setting, this method affects the haemodynamics of the cardiovascular system and the perfusion of the target organ. From the point of view of its character, the necessity for invasive application, and the function thereof in the conditions of the cardiovascular system, ECMO is regarded as a risky method accompanied by a number of complications. Among the critical complications are thromboembolic complications affecting the central nervous system (CNS) and haemorrhagic complications. The goal of this paper is to present and verify the prerequisites for the formation of periprocedural embolisms affecting the CNS and to evaluate the regional haemodynamics of the CNS. This is done by analysing the presence of embolisms and by analysing the parameters of blood flow rates in the right common carotid artery (arteria carotis communis-ACC) and the corresponding oxygenation of the brain tissue during various flow rate parameters generated by the ECMO support on induced heart failure in a biological porcine model. In the first section of the paper, 8...
Electrical stability of the heart during hypothermia-induced potassium plasmatic level changes and after modulation of the autonomic nervous system by renal denervation.
Kudlička, Jaroslav ; Kittnar, Otomar (advisor) ; Nováková, Marie (referee) ; Danzig, Vilém (referee)
Malignant ventricular arrhythmias are a common cause of sudden cardiac death. Moderate therapeutic hypothermia (MTH) is routinely used in post-resuscitation care for anticipated neuroprotective effects. However, the safety of MTH in terms of the electrical stability of the heart has not been satisfactorily proved yet. Also, the increased sympathetic tone in patients with heart failure contributes to a higher incidence of malignant ventricular arrhythmias. The aim of this work was to verify the safety of MTH as regards the inducibility of ventricular fibrillation (VF) in the pig biomodel, especially in relation to spontaneous changes in the kalemia and QT interval. Furthermore, we assumed that renal denervation (RDN) could reduce the inducibility of VF. In the first part of the thesis, the extracorporeal cooling was introduced in fully anesthetized swine (n = 6) to provide MTH. Inducibility of VF was studied by programmed ventricular stimulation (8 basic stimuli with up to 4 extrastimuli) three times in each biomodel under the following conditions: during normothermia (NT), after reaching the core temperature 32 řC (HT) and after another 60 minutes of stable hypothermia (HT60). VF inducibility, effective ventricular refractory period (ERP), QTc interval, and potassium plasma level were measured. In...
Changes of the electric field of the heart in disorders of glucose metabolism and ways of influencing them by correction of impaired autonomic nervous regulation
Fialová, Elena ; Kittnar, Otomar (advisor) ; Danzig, Vilém (referee) ; Ošťádal, Petr (referee)
Diabetes mellitus (DM) is not just a simple metabolic disorder, however, it is considered to be a cardiovascular disease of a metabolic origin. This is apparent especially when speaking about type 2 diabetes (DM II). Patients with DM have a high occurrence of vegetative nervous system (VNS) disorders that manifest themselves as an increased activity of the sympathetic nervous system that correlates with peripheral autonomic neuropathy and is considered to be the major pathophysiological mechanism for the development of DM II. The objective of our study was to determine whether a comprehensive spa treatment (ST) may affect the level of the sympathetic tone of patients suffering from DM II. As an indicator of the sympathetic tone, selected electrocardiographic parameters derived from the HRV, microvolt T-wave alternans, and microvolt R-wave alternans were evaluated. The electrophysiological examination of patients was performed before and after a three-week spa treatment using the KARDiVAR system. The method is used to examine the current state of the autonomic nervous system and carry out an analysis of risk factors and adaptive capabilities of the organism. The results showed favorable changes in DM II patients after the ST, primarily in terms of reduced sympathetic adrenal system activity,...
Selected differences in pathophysiology of cardiovascular system in women
Yang, Shiann-Guey ; Kittnar, Otomar (advisor) ; Ošťádal, Petr (referee) ; Danzig, Vilém (referee)
(summary of doctoral dissertation) It has become increasingly apparent in recent years that there are important differences of many cardiovascular disorders including ventricular tachycardias in men and women. Gender differences have been observed in the epidemiology, pathogenesis and clinical presentation of various ventricular arrhythmias. Physiological menopause occurs as a part of a woman's normal aging process being based on the natural cessation of estradiol and progesterone production by the ovaries. The dramatic fall in circulating estrogens levels at menopause impacts many tissues including cardiovascular system. Because the incidence of coronary heart disease (CHD) rises significantly after menopause, it has been hypothesized that women's CHD advantage before menopause (in comparison to men of the same age) could be due to the protective effects of estrogens. However, controversial results have been reported since early nineties until today. While some studies found reduction in the incidence of CHD and in mortality from cardiovascular diseases some other studies failed to provide any evidence for an independent role of estradiol levels in determining CHD in postmenopausal women and some studies even found positive association of endogenous estradiol with the risk of CHD among women above...

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