|
|
Effect of pulsatility of blood flow on parametres of vascular damage in patients with mechanical circulatory support
Ivák, Peter ; Netuka, Ivan (advisor) ; Štádler, Petr (referee) ; Ošťádal, Petr (referee)
Ventricular assist devices are an important therapeutic modality in advanced surgical therapy of end-stage heart failure. Devices mainly used until recently generate primarily non- pulsatile blood flow. Despite indisputable clinical success of this therapy, we encounter complications specific to the devices with continuous flow. Complications are mostly attributed to increased shear stress and changes in blood vessels, blood elements and endothelium. The aim of this study was to determine the effect of continuous blood flow on the vasculature and blood elements by longitudinal monitoring of selected biomarkers of vascular health. During the study we monitored circulating microparticles, endothelial progenitor cells and stem cells and examined degradation dynamics of von Willebrand factor and its function. Results obtained in our study confirm the hypothesis of changes in the dynamics of studied markers dependent on the change of characteristics of blood flow. The possible negative effect of continuous flow on monitored parameters was observed in tracked period. In degradation of the high molecular weight von Willebrand factor multimers the probable positive effect of arteficial pulsatility was observed. Further research can provide important data for the development of specific characteristics...
|
|
|
Mild therapeutical hypothermia and oxidative stress after cardiac arrest
Krüger, Andreas ; Ošťádal, Petr (advisor) ; Vízek, Martin (referee) ; Rokyta, Richard (referee)
Successfull cardiopulmonary resuscitation is an essential life-saving tool; nevertheless, general ischemia during cardiac arrest may trigger different pathways that could turn even into a fatal damage; this condition is called post-cardiac arrest syndrome. It has been repeatedly shown that oxidative stress (OS) plays one of the key roles in the development of ischemia-reperfusion injury. However, current evidence on the possible participation of OS in the pathogenesis of post-cardiac arrest syndrome is insufficient. We tested following hypotheses: (i) ischaemia-reperfusion injury after cardiac arrest is accompanied by OS and (ii) mild therapeutical hypothermia decreases OS cardiac arrest. In the experimental part of our work we studied the effects of hypothermia and normothermia on hemodynamic parameters, markers of organ damage and on the OS burden in porcine model of cardiac arrest. Furthermore, we compared the effects of hypothermia with ischaemic postconditioning and nitric oxide administration in the porcine model of extracorporeal cardiopulmonary resuscitation. We found protective effects of hypothermia on all major endpoints including OS in comparison with normothermia; moreover, hypothermia improved also selected variables compared to ischemic postconditioning and nitric oxide. In the...
|
|
|
Vasopresin and its analogues in treatment of cardiac arrest
Truhlář, Anatolij ; Černý, Vladimír (advisor) ; Kasal, Eduard (referee) ; Ošťádal, Petr (referee)
Vasopressin and its analogues in treatment of cardiac arrest Introduction: Recent guidelines for cardiopulmonary resuscitation (CPR) recommend use of drugs as an integral part of treatment. Vasoactive drugs have been used in resuscitation to increase myocardial and cerebral perfusion during chest compressions. Resuscitation research is trying to find alternative vasopressors to adrenaline, for which the long-term survival benefit has not been proven. Successful use of terlipressin in cardiac arrest (CA) was documented in small studies in children and some rare case reports. Terlipressin has never been tested in CA of cardiac aetiology in any clinical or experimental study. Objectives: We aimed to evaluate the role of catecholamines and non-adrenergic vasopressors, vasopressin and terlipressin, during CPR based on review of selected trials. Introduction of a standardized experimental porcine model of ventricular fibrillation (VF) was done for research of therapeutic interventions during CPR. We aimed to evaluate the effects of terlipressin with adrenaline on perfusion of vital organs during prolonged CPR compared to placebo with adrenaline. We tested our hypothesis that terlipressin, if given simultaneously with the first dose of epinephrine during CPR for VF, increases CorPP (coronary perfusion pressure) or...
|
|
|
The importance of genetic testing in prevention of bleeding complications of invasive procedures in cardiology
Sionová, Magdalena ; Moťovská, Zuzana (advisor) ; Ošťádal, Petr (referee) ; Pudil, Radek (referee)
Background: Periprocedural bleeding is the most common complication related to coronary angiography (CAG) and percutaneous coronary intervention (PCI) and it is associated with worse short-term and long-term prognosis. Determining risk factors and genetic variations associated with increased bleeding risk may improve use of avoidance bleeding strategies in prevention of bleeding. Aim: The aim of our study was to a) identify independent risk factors (of the baseline characteristics, clinical, laboratory a procedural data) associated with a higher risk of periprocedural bleeding b) to validate predictive value of CRUSADE and NCDR bleeding risk stratification algorithms c) to analyze the association between the presence of selected single nucleotide polymorphisms of key platelet proteins (GPIa, GPVI, P2Y12, COX-1) and the risk of periprocedural bleeding. Methods: The study included 73 patients with acute or chronic ischemic heart disease who developed bleeding complication within 30 days after invasive procedure (CAG/PCI). The control group consisted of 331 patients without bleeding. Baseline characteristics, clinical state at admission, laboratory data (creatinine, blood count, INR) and procedural data were evaluated. The CRUSADE and NCDR algorithms for bleeding risk were retrospectively applied on both...
|
|
|
Comparison of metabolic parameters, hormonal level changes and cardiovascular risk in patients with gestational diabetes with healthy pregnant controls using ECG mapping method and other noninvasive cardiologic methodics
Žákovičová, Eva ; Charvát, František (advisor) ; Ošťádal, Petr (referee) ; Rušavý, Zdeněk (referee)
History of GDM not only increases the risk of developing type 2 diabetes mellitus, but also the risk of cardiovascular disease that is independent of type 2 DM. Hyperglycemia leads to significant electrophysiological, functional and structural changes in the cardiovascular system and they are interrelated. One of our main goals was to evaluate metabolic and hormonal changes and detect changes in the cardiovascular system and assess their mutual relations in condition of optimal metabolic control using a predetermined treatment algorithm. Echocardiography findings in our group of patients with GDM confirm the presence of incipient structural changes in left ventricular (significantly thicker IVS, PWD and RWT) compared to the control group. The original finding is that, under optimal compensation of diabetes any of monitored parameters of left ventricular diastolic function have not been changed. Furthermore, we found that complex metabolic care with optimal values of blood sugar together with weight gain monitoring in women with GDM leads to improvement of the 24-hour blood pressure profile without increased prevalence of non-dipper women and that nocturnal decline in BP depends on fasting plasma glucose. ECG body surface mapping did not show statistically significant changes in depolarization and...
|
|
|
Platelet reactivity during antiplatelet therapy
Paulů, Petra ; Osmančík, Pavel (advisor) ; Dyr, Jan (referee) ; Ošťádal, Petr (referee)
INTRODUCTION: Dual antiplatelet therapy is the basis of the treatement of patients with coronary artery disease following PCI. It demonstrably reduces the risk of ischemic complications of these patients and thus the morbidity and mortality. Despite all the effort we can see the recurrence of ischemic complications and worsening the prognosis in considerable percentage of patients. Resistance to treatement and resistance to clopidogrel can be marked as reason of therapy failure. AIM: The aim of our study was to a) define the incidence of clopidogrel resistance in real practise b) specify the factors which are associated with clopidogrel resistance c) determine whether the platelet reactivity measured by VerifyNow can be influenced by clopidogrel dose titration d) define the factors which are associated with worse prognosis of patients treated with dual antiplatelet therapy METHODS: We enrolled consecutive patients after PCI who were indicated to dual antiplatelet therapy. The blood samples were drawn within 24 hours after PCI and standart biochemical, hematological and coagulation parametres were determined. Also the serology and genetic analysis and VerifyNow test to determine the platelet reactivity were done. The PRU cut off value 240 was specified as the borderline of ineffective answer to clopidogrel...
|
|
|
Evaluation of nutritional status and cardiac risk in patients with anorexia nervosa.
Pálová, Sabina ; Charvát, Jiří (advisor) ; Ošťádal, Petr (referee) ; Zamrazil, Václav (referee)
Anorexia nervosa (MA) is serious psychiatric disease associated with significant mortality. One of the main causes of mortality in these patients is cardiac complications. In 2003 - 2010 we examined 30 patients with established diagnosis of MA. Routinely used nutritional parameters are normal even in severe malnutrition in MA patients and we can ́t use them to diagnose or monitor nutritional status. Therefore we evaluated plasma aminoacids levels to detect minor changes of protein metabolism. According to our results we found mild hyperaminoacidemia and significant elevation of Gly/Val and Phe/Tyr ratio. In the second part of our research we performed non invasive examination s in risky patients with AN to consider possible cardiac complications. Results of ECG and echocardiography confirm results of the previous published studies. Original finding is significant decrease in flow mediated dilatation of brachial artery and its normalization after realimentation. We found also in ambulatory blood pressure monitoring significant decrease in blood pressure during the active period which was the consequence of changes in the heart rate variability. Decrease of the blood pressure in patients with AN in standing position was associated with increase of HF power in supine position and particularly with the lack of...
|
|
|
NITRIC OXIDE AND REACTIVE OXYGEN SPECIES IN ACUTE CORONARY SYNDROME
Šnorek, Michal ; Herget, Jan (advisor) ; Ošťádal, Petr (referee) ; Al-Hiti, Hikmet (referee)
In cardiology, there are different conditions associated with the release of free radicals in some forms of hypoxia, such as ventilatory hypoxia or reduced perfusion. The role of free radicals during hypoxia in cardiology is the key point of our interest. In presented thesis, we have focused on hypoxia-induced pulmonary vasoconstriction and acute myocardial ischemia. Hypoxic pulmonary vasoconstriction (HPV), an important physiological mechanism, is regulated by changes in the production of and interactions among reactive oxygen species (ROS). There is controversy, however, over whether HPV is mediated by an increase or a decrease in ROS production. Also, the role of nitric oxide (NO) in HPV remains unclear. Our results indicate that inhibition of HPV by the superoxide dismutase mimetic tempol does not depend on either NO production or a decrease in basal vascular tone. The effect of three-day fasting on cardiac ischemic tolerance was investigated in another experimental model. Short-term fasting conclusively decreases ROS production. Three-day fasting effectively protected rat hearts against major endpoints of acute ischemia-reperfusion injury. It prevented severe ventricular arrhythmias and reduced the extent of myocardial infarction. These beneficial effects can be linked to altered mitochondrial redox...
|
|
|
Advanced heart failure in the 21st century: new physiological insights and new therapeutic avenues
Boilson, Barry Anthony ; Aschermann, Michael (advisor) ; Vítovec, Jiří (referee) ; Ošťádal, Petr (referee)
Countries with developed economies are currently facing an epidemic of heart failure (HF) and the prognosis of patients with advanced HF remains extremely poor. One of the therapeutic options for patients with advanced HF is heart transplant. The number of cardiac transplants performed in USA and other states each year has stagnated despite an increasing number of cases of end-stage heart failure each year, primarily due to limited donor supply. Therefore, novel therapies for cardiac replacement (such as left ventricular assist devices, LVADs), other cardiac assistance devices including arrhythmia treatment (cardiac resynchronization therapy, CRT or implantable cardiac defibrillators (ICDs) have been tested and are being used in clinical practice. Moreover, stem cell therapy has been tested as well as a role of endogenous progenitor cells has been explored. However, effects of the novel therapeutic approaches or their combination on pathophysiology of HF as well the involvement of endogenous progenitor cells are incompletely understood, which requires further research. The main aims of the thesis with corresponding main hypotheses were three as follows. First, to study the physiological effects of LVADs on pulmonary vascular resistance and the incidence and clinical tolerance of ventricular...
|
|
|
Radial approach to coronary catheterizations and interventions
Bernat, Ivo ; Rokyta, Richard (advisor) ; Vojáček, Jan (referee) ; Ošťádal, Petr (referee)
Radial approach in coronary catheterizations and interventions has been only an alternative of the femoral approach. But due to some important advantages radial approach has a chance to become the first choice in majority of catheterized patients. The most important advantage is the reduction of vascular access site bleeding complications. Additonal benefits are patient satisfaction, cost reduction, shorter hospital stay and possibility of the same-day discharge catheterizations and interventions. The aim of our work was to try to answer three open questions: 1. is it possible to catheterize majority of our patients from the left radial artery when 90% of them are right-handed ? 2. what is the optimal care for the radial artery after the procedure in prevention and treatment of radial artery occlusion? 3. is it effective to implement radial approach in primary PCI as a first approach for STEMI patients? The first part relates the left radial approach. After construction of our special variable support for the left arm and forearm we succesfully used this approach in our studies in almost 90% of patients. The second part of this work contains our randomized trial comparing two different doses of unfractionated heparin in prevention of radial artery occlusion after diagnostic cardiac catheterizations....
|
guest ::
