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Possibilities of genetic testing in patients with pheochromocytoma and paraganglioma.
Turková, Hana ; Zelinka, Tomáš (advisor) ; Malík, Jan (referee) ; Fryšák, Zdeněk (referee)
1. Abstract Pheochromocytoma/ paraganglioma (FEO/PGL) may be developed on the basis of an inherited genetic mutation of different genes. They are associated with a high risk of developing of secondary hypertension, organ damage and metastatic disease that can be fatal. The aim was to focus on the possibility of genetic testing in patients with FEO/PGL, especially in patients with malignant tumors. The issue FEO/PGL, however, concerns not only the examination and assessment of risks arising therefrom, as well as other therapies and monitoring, including appropriate recommendations for clinical practice. We demonstrated a 20% incidence of cardiovascular (CV) complications before determining the final diagnosis of FEO/PGL, mainly arrhythmic, followed by complications of myocardial ischemia and accentuate atherosclerosis. Elevated levels of vitamin C and decreased levels of malondialdehyde (MDA) following the successful removal of the tumor demonstrated reduction of oxidative stress postoperatively. We found that early postoperative testing of levels of plasma metanephrines to confirm the success of surgical removal of FEO/PGL is already possible, since there was no significant correlation between plasma levels of metanephrines and postoperative examination interval. Distribution of frequency of metastatic...
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Cardiovascular complications in patients with end-stage renal disease.
Valeriánová, Anna ; Malík, Jan (advisor) ; Zemánek, David (referee) ; Piťha, Jan (referee)
Patients with end-stage renal disease frequently suffer from cardiovascular complications. Many factors contribute to their development: hyperkinetic circulation caused by anaemia, fluid retention and by presence of dialysis arteriovenous access; metabolic changes leading to acceleration of atherosclerosis and increase of vascular stiffness and also fluctuation of blood pressure and organ perfusion during haemodialysis, that cause repeated tissue hypoxia. We performed our research on patients in chronic haemodialysis programme. The project studying long-term patency of dialysis access showed that dialysis graft patency is negatively influenced by presence of coronary artery disease and low serum concentrations of cholesterol. In our studies about tissue hypoxia we proved that haemodialysis patients suffer from hypoxia of cerebral tissue and muscle tissue of the dialysis access arm, and that the hypoxia worsens during dialysis. Factors associated with brain hypoxia are presence of heart failure, higher BNP levels and higher erythrocyte distribution width. One of the serious consequences of brain hypoxia is development of cognitive deficit. Among the negative impact of haemodialysis on the heart, we observed left atrial dysfunction, which is a consequence of long-term remodelling and cannot be...
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Structural and hemodynamic characteristics of atherosclerotic plaques in carotid arteries with relation to endovascular manipulation during carotid artery stenting.
Špaček, Miloslav ; Zemánek, David (advisor) ; Malík, Jan (referee) ; Pařenica, Jiří (referee)
Atherosclerotic diseases including stroke are the leading causes of morbidity, mortality as well as disability in industrialized countries. Carotid endarterectomy was long considered the stan- dard approach for the treatment of atherosclerotic carotid disease, one of major causes of stroke. Over time, carotid artery stenting (CAS) has evolved as an alternative approach and is considered equivalent to surgical treatment in selected patients. Particularly in the last years, CAS has gained attention with the increasing knowledge regarding atherosclerotic plaque and cerebrovascular flow. In our study, we focused on patients undergoing CAS and evaluated structural and hemodynamic characteristics of atherosclerotic plaques together with relation to endovascular manipulation. The major part of the study includes transcranial doppler ultrasound evaluation which is able to detect flow in major cerebral arteries as well as to detect microembolizations of atherosclerotic particles during CAS. In eligible patients, we investigated the usefulness of cerebrovascular reserve (CVR) testing to predict severe hemodynamic changes in ipsilateral middle cerebral artery induced by temporary carotid occlusion during proximally protected CAS. CVR was tested by means of a breath-holding test and ophthalmic artery flow...
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Possibilities of genetic testing in patients with pheochromocytoma and paraganglioma.
Turková, Hana ; Zelinka, Tomáš (advisor) ; Malík, Jan (referee) ; Fryšák, Zdeněk (referee)
1. Abstract Pheochromocytoma/ paraganglioma (FEO/PGL) may be developed on the basis of an inherited genetic mutation of different genes. They are associated with a high risk of developing of secondary hypertension, organ damage and metastatic disease that can be fatal. The aim was to focus on the possibility of genetic testing in patients with FEO/PGL, especially in patients with malignant tumors. The issue FEO/PGL, however, concerns not only the examination and assessment of risks arising therefrom, as well as other therapies and monitoring, including appropriate recommendations for clinical practice. We demonstrated a 20% incidence of cardiovascular (CV) complications before determining the final diagnosis of FEO/PGL, mainly arrhythmic, followed by complications of myocardial ischemia and accentuate atherosclerosis. Elevated levels of vitamin C and decreased levels of malondialdehyde (MDA) following the successful removal of the tumor demonstrated reduction of oxidative stress postoperatively. We found that early postoperative testing of levels of plasma metanephrines to confirm the success of surgical removal of FEO/PGL is already possible, since there was no significant correlation between plasma levels of metanephrines and postoperative examination interval. Distribution of frequency of metastatic...
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Vascular access for hemodialysis and hemodynamics
Válek, Martin ; Lopot, František (advisor) ; Malík, Jan (referee) ; Roček, Miloslav (referee)
The study is based on the program of monitoring of the state of surgically created vascular accesses by measuring the vascular access blood flow (QVA). Besides the comprehensive analysis of factors influencing the value of QVA it discussed in detail hemodynamic changes caused by the presence of non-physiological arteriovenous anastomosis. The study is based on data acquired in the course of more than 10 years during which this program has been routinely used and is based on data from 506 patients with a total of 4,296 measurements of QVA. In patients, QVA is significantly inter- and intraindividually variable. QVA is significantly influenced by multiple factors and corresponds also to the overall health of the patient. No simple factor has been proven to predominantly influence QVA. The study points out the significant long-term physiological variability of QVA (23%) as a parameter that was not taken into account despite its importance in deciding on the correct indication of radiological interventions. The study also analyzes the strong correlation between QVA and cardiac output. It brings a new method of evaluation of the influence of vascular access on myocardium through a calculation of the load of left ventricle and shows that there is a strong non-linear dependency between the flow and the...
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Feeding artery of vascular accesses for hemodialysis: model of arterial adaptation to high blood flow
Tuka, Vladimír ; Malík, Jan (advisor) ; Vízek, Martin (referee) ; Zicha, Josef (referee)
Background: Arteries adapt their diameter to changing haemodynamic conditions to maintain constant wall shear stress, the force generated by flowing blood on endothelial cells. The feeding artery of haemodialysis vascular accesses is a human model of arterial adaptation to chronically high blood flow and thus to high wall shear stress. The process of arterial adaptation is endothelium dependent. Endothelial dysfunction related to End-Stage Renal Failure, diabetes mellitus, dyslipidemia may impair also the dilatation of the feeding artery of vascular accesses. First the review of the literature presents in three parts different aspects of arterial adaptation: 1) arterial adaptation with focusing on the role of haemodynamic factors, 2) the influence of end-stage renal disease on arterial adaptation, 3) feeding artery of vascular accesses as a model of arterial response to chronic increase in blood flow. Methods: We examined the feeding artery of radial and brachial polytetrafluoroethylene grafts shortly after and one and two years after access creation. We used duplex ultrasonography to obtain internal diameter and blood velocity in the feeding arteries. We calculated wall shear rate as 4 x blood velocity / internal diameter and used it as approximation of wall shear stress. Results: In the first study we...
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Assessment of the Cathetrization Programme in a Haemodialysis Centre
Mašek, Petr ; Malík, Jan (referee) ; Lopot, František (advisor)
This diploma thesis deals with complex quality assessment of catheterization programme run at Strahov Internal Medicine Department of the General Faculty Hospital in Prague. The evaluation was done according to K/DOQI 2006 international guidelines. The aim was to evaluate primary success of catheterization, probability of maintaining catheter functionality in time, the risk of its thrombotization and presence of infection. The evaluation was performed using Kaplan-Meier method. Moreover, the effect of additional enhancements for maintaining catheter functionality (TEGO Connector, Biopatch, heparin and Citra-LockTM) and the predictive value of selected hematologic parameters of long-term functionality of the catheters (hematocrit, plasma D-dimers) was assessed. The latter was performed on a small sample of patients. The possibility of detection of the catheter point position by measuring recirculation and its effect on dialysis was investigated by comparing X-ray control of the catheter point position to the value of recirculation measured on catheters connected either normally or inversely to the extracorporeal circulation device. Significance of the pressure values measured at input and output catheter lines was evaluated as a possible marker of the catheter functionality. Based on the analysis results,...
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