Contributor:

Frontczak-Baniewicz, Małgorzata (Promotor) ; Gewartowska, Magdalena (Promotor pomocniczy)

Publisher:

Instytut Medycyny Doswiadczalnej i Klinicznej im. Miroslawa Mossakowskiego PAN

Place of publishing:

Warszawa

Degree name:

doktor

Level of degree:

2

Degree discipline :

medical sciences

Degree grantor:

Mossakowski Medical Research Center PAS

Abstract:

Viral heart diseases develop due to changes, most often as a result of an autoimmune response induced by viruses through molecular mimicry. Endomyocardial biopsy is the only diagnostic tool that supports the analysis of the tissue changes. Parvovirus B19 is the most frequently detected in endomyocardial biopsy samples taken from DCM patients. The main goal of this research was the electron-microscopic evaluation of the cardiovascular unit elements and the analysis of changes in their ultrastructure in the course of parvoviral heart infection. The detailed objectives included: • Development of a scheme of changes taking place in the myocardium in the course of B19V infection. • Determining whether there is a relationship between the ultrastructural morphology of the cardiovascular unit and the number of B19V copies in EMB, clinical condition of patients, echocardiographic examination results and laboratory tests results. All patients had non-invasive tests routinely performed in the diagnosis of the heart failure and were assessed according to the NYHA criteria for the severity of cardiovascular failure symptoms. The diagnostics of the patients included in this study had to be extended for coronary angiography and endomyocardial biopsy from the wall of the left ventricle. The biopsy material was assessed for the presence of inflammation. qPCR and RT-qPCR were used to identify the genetic material of viruses in the myocardium. Samples were assessed using transmission electron microscopy. The most important results: 1) Destruction of the contractile apparatus, morphological features of oxidative stress, edema of the endoplasmic reticulum, pathologies in the nuclear envelope, morphological features of the rough endoplasmic reticulum enlargement and features of mitochondrial crest degradation were observed in the ultrastructural image of the EMB samples taken from patients with B19V. Some mitochondria had ruptured outer membrane, and there were clusters of glycogen in their area, sometimes surrounded by membrane. There were numerous loop vessels and they sometimes had high, hypertrophic endothelium and narrow lumen. Fibrous material and fibroblasts were observed in the extracellular space. 2) Pathological changes in ultrastructure of the CVU elements were more pronounced in patients with higher NYHA class, higher levels of NT-proBNP and troponin. Left ventricular end-diastolic dimension and left ventricular ejection fraction were not directly related to the CVU pathologies. 3) G4 group represented the first stage of viral heart infection - intensive viral replication with normal LVEF. The dilation of the left ventricle and deterioration of its function were the next stage (group G3). Further stage of the infection was the end of viral replication (G1). The G2 group represented population of patients, in which parvovirus B19 is only a bystander. 4) There was no correlation between the left ventricular ejection fraction and the number of parvovirus B19 DNA copies detected in the biopsy samples. Conclusions: 1. No significant differences between studied groups were found in light microscopy, but the examination using transmission electron microscopy seemed to be important supplement. 2. The picture of ultrastructural changes of the elements of the cardiovascular unit in the patients with viral heart disease caused by B19V was different than in the patients with left ventricular dilatation with no viral genetic material. 3. Pathological changes in the morphology of the cardiovascular unit were correlated to the number of parvovirus B19 copies in EMB, with the severity of heart failure symptoms according to the NYHA criteria, as well as with NT-proBNP and troponin I levels in peripheral blood serum. 4. The group of patients with <500 copies of B19V represented the final stage of parvovirus B19 infection. Myocardium demonstrates significant degree of destruction and it is connected with poor prognosis.

Detailed Resource Type:

PhD Dissertations

Resource Identifier:

oai:rcin.org.pl:235819

Source:

IMDiK PAN, sygn. ZS413 ; click here to follow the link

Rights:

Creative Commons Attribution BY 4.0 license

Terms of use:

Copyright-protected material. [CC BY 4.0] May be used within the scope specified in Creative Commons Attribution BY 4.0 license, full text available at: ; -

Digitizing institution:

Instytut Medycyny Doświadczalnej i Klinicznej im. M. Mossakowskiego Polskiej Akademii Nauk

Original in:

Library of the Mossakowski Medical Research Institute PAS

Projects co-financed by:

Operational Program Digital Poland, 2014-2020, Measure 2.3: Digital accessibility and usefulness of public sector information; funds from the European Regional Development Fund and national co-financing from the state budget.

Access:

Open