Vit Martin Matejka

Publications

• [Effect of biological glues on vascular wall in an experimental model of aortic dissection].

  T Martinca, M Jonák, Z Tonar, K Witter, V M Matejka, S Rokosný

  Rozhledy v chirurgii : měsíčník Československé chirurgické společnosti. 02/2011; 90(2):134-40.

  The use of biological glues and their application between the two dissection layers and into the anastomosis region is a common integral part of surgical management of thoracic aortic dissections. The aim of the experimental study was to assess and evaluate histopathological changes of vascular wall... [more] The use of biological glues and their application between the two dissection layers and into the anastomosis region is a common integral part of surgical management of thoracic aortic dissections. The aim of the experimental study was to assess and evaluate histopathological changes of vascular wall following deposition of the following three types of glue--GRF, Tissucol, Bioglue, based on qualitative and quantitative parameters. The secondary aim of the study was to assess dynamics of these changes depending on the glue effect duration and to formulate expected behaviour of the vascular wall during the time beyond the experimental period. The dissection model was performed with pigs of the same gender and age, assigned to four groups. Different glues were used to close artificial infrarenal aortic dissections in Group 1-3, while direct suturing and no glue was used to close false lumini in Group 4. Samples of the dissected aorta were then collected at Month 1, 6 and 12 and then histologically examined. Upon assessment of the whole group of qualitative and quantitative parameters, the most significant changes in the smooth muscle histological picture were observed with the use GRF glue. The smooth muscle changes following the Bioglue application and, in particular, Tissucol glue application, are similar to changes observed in Group 4, where no glue was used. Based on the results, the authors present a hypothesis that, in a long-time horizont, vascular wall destructions, eventually redissections, are likely to occur more frequently in patients, in whom GRF glue is used.
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  Tissue reaction to three different types of tissue glues in an experimental aorta dissection model: a quantitative approach.

  Kirsti Witter, Zbyněk Tonar, Vít Matějka, Tomáš Martinča, Michael Jonák, Slavomír Rokošný, Jan Pirk

  Histochemistry and cell biology. 11/2009;

  Tissue glues are used during surgical treatment of acute aorta dissection although some glues release toxic products and thus alter the histological structure of the vessel wall. The aim of our study was to use a porcine experimental model of infrarenal aorta dissection to compare histological chang... [more] Tissue glues are used during surgical treatment of acute aorta dissection although some glues release toxic products and thus alter the histological structure of the vessel wall. The aim of our study was to use a porcine experimental model of infrarenal aorta dissection to compare histological changes of the vessel wall 1, 6 and 12 months after application of BioGlue, Gelatin-resorcin-formaldehyde (GRF) glue and Tissucol. For quantification, stereological methods were used. All types of glue caused stenosis, GRF most and Tissucol least severely. With increasing postoperative survival time, stenosis was again reduced. Elastine length density decreased with increasing survival time in Control as well as in all Experimental groups. The immunohistochemical phenotype of vascular smooth muscle cells was similar in Tissucol and Control samples. In GRF samples, actin, desmin and vimentin expression changed most severely. Similarly, number and distribution of vasa vasorum in the aortic wall was altered most severely in GRF samples. They tended to return to normal with increasing postoperative survival time, but at a slow rate in the GRF samples. It can be concluded that GRF causes the most severe histopathological changes within the treated aorta, which could be a reason for late failures of dissection surgery. However, glue handling and adhesive properties have to be taken into account, too, when certain glue is chosen for surgical intervention. Increased inflammation and vascularisation might even stabilise the aortic wall. Long-term experimental studies would be helpful to assess healing processes after initial disorganisation of the aortic wall structure.

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• Morphology and mechanical properties of the subrenal aorta in normotensive and hypertensive rats.

  Petra Kochova, Zbynek Tonar, Vit M Matejka, Jitka Sviglerova, Milan Stengl, Jitka Kuncova

  Biomedical papers of the Medical Faculty of the University Palacký, Olomouc, Czechoslovakia. 01/2009; 152(2):239-45.

  AIMS: This work focuses on the morphological and mechanical changes in the wall of the subrenal aorta in rats suffering from arterial hypertension and chronic renal failure induced by subtotal nephrectomy (NX). METHODS: The quantitative structural parameters were assessed using stereological methods... [more] AIMS: This work focuses on the morphological and mechanical changes in the wall of the subrenal aorta in rats suffering from arterial hypertension and chronic renal failure induced by subtotal nephrectomy (NX). METHODS: The quantitative structural parameters were assessed using stereological methods. The mechanical properties were determined using uniaxial tensile tests. RESULTS: Morphological results showed no significant differences in the wall structure of NX rats ten days following the subtotal nephrectomy in comparison with the control animals. Pronounced structural changes appeared ten weeks after the nephrectomy. The area of the profile of the arterial lumen, the volume fraction of elastin, and the elastin lamellar number in the tunica media were significantly higher in the NX rats than in the control animals. The values of the volume fraction of the smooth muscle cells in the tunica media and the lamellar unit thickness were significantly lower for the NX animals. Mechanical results showed that both kinds of tissues were characterized by a non-linear response when subjected to the tensile test. The moduli of elasticity of subrenal aortas in control and NX animals were different only for large deformations: NX samples had higher stiffness. The cyclic loading resulted in a time-dependent response for both tissue types. CONCLUSIONS: The results obtained from the NX rats ten days as well as ten weeks after operation suggested an outward hypertrophy of the aorta. The subrenal aortas of the NX animals had less strength and were less extensible than those of the control animals.