Student Researchers' Society Topics

There are two different types of acute myocardial infarction: ST elevation myocardial infarction (STEMI) and non ST-elevation myocardial infarction (NSTEMI). The patophysiological background, the epidemiology and the therapeutic strategies are different in STEMI and NSTEMI. In STEMI percutaneous coronary intervention or thrombolysis should be performed within 90 minutes, however in NSTEMI the percutaneous coronary intervention could be performed within the first 24 and 72 hours, depending on the clinical situation.

Angiography is widely used to assess the severity of coronary lesions. Despite its prevalence and extensive clinical experience with its use, many limitations of angiographic studies are well known. The ischemic significance of stenoses can often only be clarified by direct, invasive intracoronary pressure measurement (FFR). This allows a more accurate identification of the culprit lesion and allows avoiding the unnecessary angioplasty of a hemodynamically insignificant stenosis. 3D reconstruction with digital angiography can help determine the degree of constriction. In these models, virtual FFR values can be determined by simulating flow and pressure values. The aim of the study is to model FFR measurement using coronary angiography and to compare the results.

Co-supervisor: Dr. KUPÓ, Péter

Myotonic dystrophy is the most common multisystemic mgenetic muscle disorder. Besides the reorganization of striped muscles, the cardiac muscle is also affected. The most common cardiac manifestations are consuction and other heart rhythm disturbances, which are caused by the changes in the heart's pacemaker and conducive systems, due to muscle reorganization. In the course of our research we aim to investigate the role of invasive electrophysiological examination in the cardiologic risk evaluation in myotonic dystrophy.

Zero-fluoroscopic ablation techniques reduce the harmful effects of ionizing radiation during electrophysiology procedures. We aim to test the efficiency and safety of a zero-fluoroscopic strategy using 3D electroanatomic mapping system for diagnostics and radiofrequency ablation of AV nodal reentry tachycardias in a retrospective study.

Zero-fluoroscopic ablation techniques – have been able to use since september of 2017 in Pécs - reduce the harmful effects of ionizing radiation during electrophysiology procedures. We aimed to test the efficiency and safety of a zero-fluoroscopic strategy using 3D electroanatomic mapping system for diagnostics and radiofrequency ablation of supraventricular tachycardias (SVT) in a retrospective study.

Co-supervisor: Dr. DEBRECENI, Dorottya

In selected cases, in patients with atrial fibrillation AV node ablation is performed. These procedures are usually performed with fluoroscopy guidance. However, use of intracardiac echocardiography (ICE) for AV node ablation has become available in recent years. In our study we aim to compare conventional, fluoroscopy-guided vs ICE-guided CTI ablations in patients underwent AV noda ablation due to atrial fibrillation.

The number of transcatheter ablation procedures for atrial fibrillation grows year by year in Hungary. During the procedure pulmonary vein isolation is performed. Lately the cryoballoon technique has become widespread available besides radiofrequency ablation. Moreover, contact force sensing catheters has been available in radiofrequency ablation. In our research the procedures performed by these two different methods will be compared and analyzed.

Co-supervisor: Dr. DEBRECENI, Dorottya

Conventionally, invasive electrophysiology procedures are performed with fluoroscopy guidance, however different ablation approaches became available in the last years. Our study we compare the 3D electroanatomical mapping system guided vs. intracardiac echocardiography guided slow pathway ablation is patients with AVNRTs undergoing catheter ablation.

Cavotricuspidal isthmus (CTI) is the target of the ablation for patients with atrial flutters. These procedures are usually performed by only-fluoroscopy navigation. However, use of intracardiac echocardiography for CTI ablation has become widespread in recent years. In our study we aim to compare conventional, only fluoroscopy-guided vs ICE-guided CTI ablations in patients underwent invasive electrophysiologic procedures due to atrial flutters.

The number of transcatheter ablation procedures for atrial fibrillation grows year by year in Hungary. During the procedure pulmonary vein isolation is performed. Conventionally, these procedures are performed with the use of steerable sheaths. Recently, steerable sheaths that can be visualized on 3D mapping system are available which can reduce the use of fluoroscopy during these procedures. In our research the procedures performed by these two different tools will be compared and analyzed.

Co-supervisor: Dr. KUPÓ, Péter

The number of transcatheter ablation procedures for atrial fibrillation grows year by year in Hungary. During the procedure pulmonary vein isolation is performed. Lately the cryoballoon technique has became widespread available besides radiofrequency ablation. In our research the procedures performed by these two different methods will be compared and analyzed.

Co-supervisor: Dr. SZABÓ, Dóra

Sportcardiology is a popular and important topic in these days through the increasing incidence of sudden cardiac death by the young and „healthy” sportsmen. In most cases the cause of sudden cardiac death is an occult cardiac disease. A lot of researches have already shown the differences between the phisiological sport heart and pathological cardiac conditions. In this study we examine sportsmen competing in different sport arts. Special ECG, particular echocardiographic examination furthermore spiroergometry are performing. The sportsmen with pathological results have a heart MRI examination, too. The aim of our examination is to compare the results of different (static or dinamic) sports and to configure a relative fast screening method for the everyday routine of sportsmen’s screening.

The indications of percutaneous coronary interventions are addressed, regarding especially the cases of myocardial infarctions and the consequently occurring cardiogenic shocks. In the latter situation, full revascularization plays an important role. The different catheter based techniques are discussed, which are utilized during the diagnostic and interventional part in the catheter based revascularization.

Heart rate variability (HRV) analysis is considered as a non-invasive ECG-based technique for the investigation of autonomic nervous system. Due to the multiple associations of the vegetative nervous system, several factors affect HRV. On one hand it means the wide range of applicability, however, on the other hand, results in low specificity. Accurate measurement requires special study-design, technical conditions and presentation. The topic covers both methodical and clinical investigations including cooperation with other specialties as well.

Acute coronary syndrome results mainly from rupture of an inflamed thin-capped plaque with secondary thrombus formation. A sustained, completely occlusive thrombus typically leads to an ST-segment–elevation myocardial infarction (STEMI). Chemokines and cytokines have been suggested to orchestrate the inflammatory processes during atherogenesis, plaque destabilization, and infarct healing. We aim to identify novel biomarkers (e.g. cytokines and chemokines) of the pathophysiological processes during the various stages of STEMI, which may improve risk stratification in this potentially life-threatening condition.

Several methods are available for the diagnosis of coronary stenosis, of which the detection of the hemodynamic relevance is limited. The most significant developmental need and tendency focus on are techniques that determine the fractional flow reserve (FFR) without the use of an invasive pressure measuring wire by calculating non-invasive virtual fractional flow reserve (vFFR) from a three-dimensional reconstruction of the coronary angiogram. The three-dimensional (3D) geometry of the coronary artery can be analyzed from the coronarography with 3D reconstruction software. Computational fluid dynamics (CFD) allows a comprehensive, in silico study of fluid properties after 3D reconstruction of vascular structures. In addition to the existing study data, it can be assumed that CFD examination of the coronary sections results in the detection of flow parameters that are important for plaque progression.

Co-supervisor: Dr. JÁNOSI, Kristóf

Atrial fibrillation is the most common sustained arrythmia. In some cases, catheter ablation is performed to maintain the sinus rhythm. In our study, we compare the clinical characteristics, procedural data and long-term outcomes of patients underwent pulmonary vein isolation due to paroxysmal vs. persistent atrial fibrillation.

Co-supervisor: Dr. JÁNOSI, Kristóf

Atrial fibrillation is the most common sustained arrythmia. In some cases, catheter ablation is performed to maintain the sinus rhythm. In our study, we examine the clinical characteristics, procedural data and long-term outcomes of patients underwent pulmonary vein isolation due to persistent atrial fibrillation.

Co-supervisor: Dr. TAMÁS, Andrea

Pituitary adenylate cyclase activating polypeptide (PACAP) is a multifunctional neuropeptide having cardioprotective effects in various animal models. In our study, we examine the change of the PACAP levels in patients undergoing pulmonary vein isolation due to atrial fibrillation.

In addition to the classical, widespreadly used echocardiographic methods more new, special techniques (tissue Doppler imaging, strain, strain rate) have been developed. Systolic or diastolic functions of both the left and right ventricles as well as the atria are investigated by applying these new techniques in some special diseases (systemic sclerosis, COPD, restrictive cardiomyopathy, etc.) complicated by heart failure. In addition to the echocardiographic methods, serum levels of some biomarkers (e.g. NT-proBNP, galectin-3, VEGF) as well as estimation of the functional capacity (6 minute walk test, cardiopulmonary exercise test) are also used.

Pathologic cardiac hypertrophy is induced by direct mechanical wall stress and by circulating and paracrine/autocrine factors. These factors can activate specific signaling pathways, such as mitogen-activated protein kinases (MAPKs) and calcineurin, which leads to increased expression of certain genes characteristic of cardiac hypertrophy, the so-called fetal gene program. Transcription factors play crucial role in integrating these cytosolic signaling cascades. We aim to characterize the specific functions of GATA-4, NF-κB and STAT3 in the regulation of cardiac hypertrophy in experimental models. Our studies may pave the way for the development of novel strategies in combating adverse remodeling and heart failure.

Gestational diabetes occuring in approximately 7-14% of pregnancies may result in both maternal or foetal complications (preeclampsia, placental insufficiency, premature birth, birth defect). Our aim is to investigate if there is any sign of myocardial or vascular dysfunction even before the diagnosis of gestational diabetes. Echocardiography is performed to examine the systolic and diastolic function of the heart. An easy-to-perform oscillometric method (Arteriograph) will be used to measure arterial stiffness parameters. Laboratory parameters that can reflect the function of the myocardium and the arterial system will also be studied (Nt-proBNP, TNF-alfa, PAI-1, ADMA, adiponectin).

The development of cardiac remodeling is associated with fundamental changes in the molecular programs of the heart including the reactivation of fetal gene programs, deregulation of neurohormonal systems as well as the activation of senescence and various forms of cell death. It has long been considered that these gene programs are primarily under the control of protein-based regulatory systems (i.e. transcription factors and chromatin modifiers). It turned out that ~75% of the human genome is actively transcribed into RNA but only ~2% is translated into proteins. Understanding the functional significance of these non-coding RNA transcripts in versatile cellular processes is the subject of intense investigation. According to the most recent estimates, the human genome encodes for ~2000 different microRNAs and ~56000 long non-coding RNAs. Our main goal is to identify novel cell-type and context-specific interactions between, microRNAs, long non-coding RNAs, and mRNAs in regulating cardiac remodeling using the combination of in silico predictions, in vitro cell culture experiments, and animal models.

Large amount of evidence is now available on the crucial role of preclinical organ damage in determining the cardiovascular risk of individuals. Arterial stiffness parameters are commonly used for this purpose, to identify structural and functional changes of the arteries in the development of atherosclerotic disease. Recent European guidelines (ESC/ESH) recommended the assessment of arterial stiffness, as an evidence of target organ damage. However, measuring arterial stiffness parameters is currently not sufficiently widespread, and thus the information it provides remains desirable but difficult to obtain. According to the same guidelines “it might be more widely recommended if its availability were greater”. Novel developments offer different non-invasive, user friendly examination methods, which could solve this controversy. The aim of our study is overcome these limitations and compare recently validated, time-saving, low expense systems: the carotid Doppler echo-tracking system and the oscillometric equipment with the carciac CT and MRI methods.

During coronarography the identification and characterization of stenosis are important, however there are only indirect information about the histopathological characteristics of these lesions, and the severity of the ischemia could not be judged properly in some cases. The latter could be characterized by the utilization of pressure wire measurements, especially via the fractional flow reserve (FFR). The former could be characterized by the use of intravascular ultrasound (IVUS) and optical coherence tomography (OCT).

Congestive heart failure is a major cause of morbidity and mortality despite recent advances in medical therapy. The most commonly used positive inotropes acting via the cAMP–protein kinase A pathway, beta-adrenergic agonists and phosphodiesterase inhibitors, provide rapid and dramatic improvements in cardiac performance, producing immediate relief of heart failure symptoms; however, the prolonged use of these agents may lead to serious adverse cardiac effects. We aim to study the functional significance of myocardium-derived secreted peptides, the so-called cardiokines, in the regulation of cardiac contractility. The characterized cardiokines and their signaling pathways may offer an attractive approach for treating patients with heart failure.

Acute Coronary Syndrome (ACS) worldwide is the third most commonly reported death among people over 65 years of age. In Europe, every sixth male and seventh female cause of death is myocardial infarction. While in the last 10 years the frequency of ST elevation myocardial infarction has decreased by 30%, and the frequency of ST elevation-free infarction (NSTEMI) has increased substantially.
PCI has proven to be a reliable semi-invasive procedure for these disorders, but high age and its often associated comorbidities may limit its benefit. Earlier studies demonstrated lower success rates and the frequent complications following intervention among elderly. The statistical method of meta-analysis is suitable for summing up the published studies in the subject, which also allows to analyzis of the of the obtained evidences and results.

Co-supervisor: Dr. FUSZ, Katalin

EuroSCORE is one of the most widely used score systems in the cardiac surgery field. Perioperative risk stratification tools are not just for predicting postoperative mortality. The indicators mentioned above and a lot of other score systems are also useful for determining the quality of care in cardiac surgery. In our retrospective study, we examine the medical records of patients who underwent coronary  artery bypass grafting (CABG), aortic valve replacement (AVR), mitral valve replacement (MVR), or had any procedure on the thoracic aorta with or without AVR in our department. The study aimed to  assess the effectiveness of EuroSCORE II in the era of COVID-19 in cardiac surgery.

In the treatment of the acute myocardial infarction, interventional revascularization through coronary intervention has become of predominant importance. A national network of catheter labs was established to provide early revascularization. Clinical characteristics of patients undergoing treatment for an event of myocardial infarction are recorded by the Hungarian Myocardial Infarction Register. Our goal is to conduct observational clinical studies with the use of register data in order to identify factors influencing the prognosis of myocardial infarct patients.

Pulmonary hypertension is a condition with heterogenous origin and poor prognosis. The diagnosis and identification of the etiology frequently requires right heart catheterization. During the RHC several parameters of pulmonary circulation is determined. The aim of the project is to clarify prognostic significance of these parameters using clinical follow-up studies.

Congestive heart failure is a major cause of morbidity and mortality despite recent advances in medical therapy. Recently, we have shown that apelin, a peptide secreted from the myocardium, is one of the most potent endogenous stimulators of cardiac contractility. We aim to characterize the signaling mechanisms underlying the positive inotropic effect of apelin. The newly identified signaling pathways may represent attractive possible targets in the treatment of heart failure.

Congestive heart failure is a major cause of morbidity and mortality despite recent advances in medical therapy. Endothelin-1, a peptide secreted from the myocardium, is one of the most potent endogenous stimulators of cardiac contractility. We aim to characterize the signaling mechanisms underlying the positive inotropic effect of endothelin-1. The newly identified signaling pathways may represent attractive possible targets in the treatment of heart failure.

The role of myocardium-derived nitric oxide (NO) in the regulation of cardiac contractility is highly controversial. Nitric oxide synthase (NOS) catalyzes the formation of NO from L-arginine. We aim to characterize the functional significance of neuronal NOS (nNOS, NOS1) and endothelial NOS (eNOS, NOS3) and the potential downstream mechanisms in modulating the contractile function of the heart under physiological conditions.

Increased production of reactive oxygen species (ROS) has been implicated in the pathogenesis of congestive heart failure. However, emerging evidence suggests a role for ROS in regulating various physiological cellular processes in the myocardium. We aim to characterize the signaling network activated by ROS in the regulation of cardiac contractility under physiological conditions.

Meta-analysis is a statistical technique for summarising, and reviewing previously published quantitative research. Practioners, clinicians have to face an informational boom of the modern medicine. There is too much information around for people to keep up to date, on the other hand high quality information is often not easy to find. Elaborating a summary of available literature and performing a critical review of the obtained data is becoming more and more important. Using meta-analysis, a specially developed statistical armamentarium that allows cumulating the available data of independent observation, enables to analyse a wide variety of questions and allows not only a summary but also an integration of the evidences with higher statistical power and more precise effect estimates.

Co-supervisor: Dr. TAMÁS, Andrea

Pituitary adenylate cyclase activating polypeptide (PACAP) is a multifunctional neuropeptide having cardioprotective effects in various animal models. We have already shown PAC1 receptors in human heart muscles, and detected that PACAP38-LI and PACAP27-LI are significantly higher in ischemic heart diseases compared with valvular abnormalities in heart tissue samples. Based on the results of the animal experiments of the last decades we assumed that PACAP might have a protective effect against ischemic injury due to its antiapoptotic effect. Moreover, several studies have already proven that there may be a significant correlation between PACAP and the severity of heart failure; furthermore as an antiapoptotic polypeptide, it can influence the progression of heart failure. Based on all of these results we examine cardiac disorders with the etiology of ischemia (such as acute myocardial infarct, ischemic heart disease) and heart failure, furthermore we are going to detect the changes of serum PACAP levels due to the different therapies. ELISA method is used to quantify the PACAP levels in human plasma. With these researches there will be known more details about the exact role of PACAP in the pathomechanism and progression of several cardiac diseases, so it might be a potential biomarker in the future.

Preclinical cardiac arrest (OHCA) is a critical condition associated with high mortality. For the definition of risk groups and the clinical management, it is of essential importance to characterize the properties that predispose to OHCA and negatively influence the clinical outcome. We received the data for our analysis from the Hungarian Myocardial Infarction Register (HUMIR). Patients who were treated with and without OHCA after a myocardial infarction (MI) in the years 2014-2017 and who underwent coronary angiography are analyzed. Multivariate regression analyses are planned to answer the following questions: Are there differences in the characteristics of patients with an MI and an OHCA compared to MI patients without an OHCA? Are there differences in the prognosis of patients with an MI and an OHCA compared to MI patients without an OHCA? What properties and characteristics of MI patients with an OHCA influence mortality and survival compared to MI patients without an OHCA? Does the time component of weekly or working days influence the treatment or outcome of MI patients with OHCA?

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During electrophysiologic procedures (EPS) most often complications are related to vascular access. In our study we aim to compare conventional, palpation-based femorals vein puncture with vascular ultrasound guided access in patients undergoing EPS.