Biomedical subjects

V Povýsilová

Publications and source records attributed to V Povýsilová.

At least 19 recordsLinked to original sources

PubMed2004

Demonstration of MyoD1 expression in oncocytic cardiomyopathy: report of two cases and review of the literature.

Oncocytic cardiomyopathy is a rare arrhythmogenic disorder usually associated with female sex, difficult-to-control arrhythmias, or sudden death of infants and children. Morphologically, it is characterized by the presence of oncocytic cells, which are diffusely distributed or form the nodular structures within the myocardium, occasionally involving the valves, with a large number of mitochondria in cytoplasms. We present two cases of oncocytic cardiomyopathy. The first case had a fatal clinical outcome, and the other case was surgically treated. The nuclear expression of skeletal muscle transcription factor MyoD1 was demonstrated in the first case, supporting the theory that oncocytic cardiomyopathy is a conduction system developmental disorder. To confirm this hypothesis, it is necessary to further investigate myogenic transcription factor program in human cardiac conduction system cells.

Cardiomyopathies↗

PubMed2003

Dehydroepiandrosterone sulphate reduces chronic hypoxic pulmonary hypertension in rats.

Pathogenesis of pulmonary hypertension includes vascular smooth muscle cell membrane depolarisation and consequent calcium influx. Usually, calcium-gated potassium channels are activated under such conditions and repolarise the membrane. However, in pulmonary hypertension they are downregulated. The authors hypothesised that pharmacological augmentation of these channels would reduce pulmonary hypertension. Dehydroepiandrosterone sulphate (DHEA-S, 0.1 mg x mL(-1)), a recently characterised activator of calcium-gated potassium channels, was given to rats in drinking water. Pulmonary arterial blood pressure, increased by 4 weeks of hypoxia (from 15 +/- 0.2 to 29.4 +/- 2.5 mmHg), was selectively attenuated in rats treated with DHEA-S for the whole duration of the hypoxic exposure (23.9 +/- 0.9 mmHg) and in rats given DHEA-S only after pulmonary hypertension had fully developed (last 2 weeks of hypoxia; 24.4 +/- 1.4 mmHg). Pulmonary vascular remodelling and right ventricular hypertrophy associated with pulmonary hypertension were also reduced by DHEA-S. Cardiac index and systemic arterial blood pressure did not differ among the groups. The authors conclude that treatment with an activator of calcium-gated potassium channels, dehydroepiandrosterone sulphate, known to be well tolerated by humans, reduces hypoxic pulmonary hypertension in rats.

Adjuvants, Immunologic↗

PubMed2001

CD 68 positivity of the so-called meconium corpuscles in human foetal intestine.

CD 68 antibodies are most frequently used as a reliable paraffin marker of histiocytes. The CD 68 clusters of antibodies recognize a 110-kDa glycoprotein associated with lysosomes and therefore these antibodies show visible reactivity with cells of the monocyte/macrophage lineage. We observed distinct CD 68 positivity of granular intraepithelial inclusions in the small intestine of 12-week-old human foetuses. These PAS positive inclusions corresponded to the so-called meconium particles, whose lysosomal origin was confirmed by electron microscopy. Our new observation shows that CD 68 antibodies are specific mainly for organelles and not for a cell type and therefore the staining of epithelial cells containing lysosomes is possible.

Antigens, CD↗

PubMed2001

[Morphology of the hypoplastic left heart syndrome from the surgical perspective].

Hypoplastic left heart syndrome (HLHS) is found in a wide spectrum of changes of the mitral valve, left ventricle and aorta. It represents a critical congenital heart disease with a small left ventricle and stenosis or atresia of the aortic and the mitral valve. The knowledge of a detailed anatomy of this lesion is necessary from the viewpoint of assessment of all possibilities of the surgical treatment, interventional cardiological procedures or foetal cardiac surgery. Sixty one hearts with HLHS from the collection of heart specimens with congenital heart malformations were reviewed. The existence of a wide spectrum of malformations of all heart structures was proved. In all the cases enlarged right atrium and right ventricle was found. In 23.0% of specimens foramen ovale was restrictive or closed. The left ventricle was small in all the hearts, extreme hypoplasia was observed in 26.2% in presence of a combination of the mitral and the aortic atresia. Most commonly, the combination of mitral stenosis with aortic atresia (36.1%) and combination of mitral and aortic stenosis (32.8%) were present. Mitral atresia with aortic stenosis was identified in 4.9% cases. The mitral valve was usually dysplastic with short and thick chordae and smaller annulus. In 39.3% of all hearts fibroelastosis of the left ventricular endocardium was present. In these cases moderate degree hypoplasia of the left ventricle in combination with mitral and aortic stenosis was often found (65.0%). All the aorta was hypoplastic starting from the aortic valve, across the ascendent part and aortic arch until the isthmus. Its diameter usually varied between 2 and 4 mm. Coarctation of the aorta was found in 16.4% hearts. Persistent left superior caval vein represented the most common associated heart lesion. From the surgical point of view, nearly in all reviewed hearts Norwood surgery, consisting in aortic reconstruction from aorta, main pulmonary artery and a patch from the pulmonary homograft could be performed. Reconstruction would be very difficult in presence of an extreme hypoplasia of the ascending aorta. Until present, possibilities to prevent the development of the left ventricular hypoplasia by a foetal surgical intervention or possibility of the surgical augmentation of the left ventricle by excision of a thick endocardium do not cross the horizons of theory.

Child, Preschool↗

PubMed1999

[Hypoplastic left heart syndrome (general review)].

The hypoplastic left heart syndrome (HLHS) is a critical congenital heart lesion with a small left ventricle in combination with stenosis or atresia of the aortic and the mitral valve. This heart disease is associated with a nearly 100% mortality at neonatal age. Until recently, this heart lesion was considered inoperable because of extremely unfavourable morphology. Introduction of the Norwood three-step reconstructive operation on one hand, and heart transplantation in neonates, on the other hand, improved the prognosis of patients with this complex heart lesion. In our country, however, this heart disease, if found during the first months of pregnancy, represents an indication for its termination, and neonates with HLHS are offered only symptomatic medical treatment. On basis of good experience from several most experienced cardiac centres we believe that it is necessary to reassess the statement considering HLHS as an inoperable disease. The main change from this aspect necessitates, however, a detailed analysis of the whole problem not only from the morphological, clinical and surgical point of view but also from philosophical, psychological, socio-economic and health care organisation aspects.

Cardiac Surgical Procedures↗

PubMed1997

[Harvesting the heart for preparation of heart valve allografts].

Allograft heart valves (AHV) are believed to be optimal prosthetic material for surgical aortic valve and/or root replacement and an ideal valved conduit for repair of some complex congenital heart defects. At the University Hospital Motol AHV were clinically used since 1983 (annually no more than twenty were collected). 1991 the Paediatric Transplant Centre was established and was entrusted to organise cadaveric hearts harvesting and to introduce the standard technology of AHV processing and banking. The results of co-operation with other Transplants Centres, as well as with coroners and forensic medicine specialists in 1992-1995 are presented. For the AHV processing 274 cadaveric hearts were collected in the Czech and Slovak Republics, 32 of them (11.7%) came from routine post-mortem and 242 (88.3%) were retrieved from multiorgan harvesting, 14 hearts were excluded for technical reasons and another five for the seropositivity of the donor (three HBSAg, one HCV and one VDRL). Another 14 AHV were not suitable for clinical use because of a congenital lesion (bicuspid aortic valve) or acquired pathology found during the AHV processing (advanced atherosclerosis) or retrospectively diagnosed at donors post-mortem (in vivo undiagnosed malignancy). The technology of processing, cryopreservation and banking of AHV as well as the clinical use of the tissue will be discussed separately.

Cadaver↗

PubMed1997

[Preparation, storage, transportation and use of heart valves for allotransplantation].

UNLABELLED: Thanks to the co-operation with Czech and Slovak Transplant Centres and with some of the Departments of Pathology and Forensic Medicine 274 hearts were collected for allograft heart valves (AHV) processing during 1992-1995. The Cardiac surgeon dissected the aortic valve with the root and the pulmonary artery trunk with the valve. Tissues were antibiotically (ATB) sterilised in cultivation medium E 199 (24 hours at 37 degrees C). ATB concentrations (mg/ml): Cepharin 0.2, Azlocilin 0.2, Tobramycin 0.08 and Amphotericin B 0.1 for harvesting at post-mortem (P) or Miconazol 0.05 for sterile retrieval during multiorgan harvesting (MOH). After sterilisation AHV were stored at 4 degrees C. 49 AHV were infected even after ATB treatment-15 of 35 collected at P (43%) and 35 of 218 procured during MOH (16%)-(p < 0.01-ch2 test). After serological screening of the donor and microbiological testing the AHV were released for clinical use. Most AHV were programmed cooled to the temperature of liquid nitrogen (-196 degrees C), in which they were stored at the Allograft Heart Valves Cryobank. Cryoprotection was achieved by 10% dimethylsulphidoxide. CONCLUSION: A technology of harvesting, processing, storage and transportation of AHV, was introduced. It enabled the routine use in many cardiac surgical units. The AHV Cryobank was established. 131 AHV were used clinically between 1992 and 1995 (transportation as far as 1300 km). 108 AHV (82.4%) were used for repair of complex congenital heart defects, while 23 (17.6%) were used for aortic valve and/or root replacement.

Heart Valves↗

PubMed1996

Congenital absence of aortic and pulmonary valve in a fetus with severe heart failure.

A case of congenital absence of both aortic and pulmonary valves with severe heart failure detected prenatally by cross-sectional and pulsed and colour Doppler echocardiography is reported in small for gestational age male fetus in 17th week of gestation. Additional double outlet right ventricle, hypoplastic left ventricle, and ventricular septal defect, as well as multiple extracardiac anomalies, were found by prenatal echocardiographic investigation and confirmed by necropsy examination. Retrograde diastolic Doppler waveforms retrieved from pulmonary artery, aorta, and umbilical arteries revealed massive insufficiency throughout both the great arteries, which eliminated diastolic placental perfusion, documented by absent anterograde diastolic flow in the umbilical vein. These prenatal echocardiographic findings may contribute to an understanding of the mechanism of rapid and progressive heart failure and growth retardation in the fetus. Severe cardiac failure may explain why congenital aplasia of both the aortic and the pulmonary valves has not been described postnatally, and only two fetal cases revealed by necropsy have been published.

Adult↗

PubMed1995

Long-term effects of prenatal indomethacin administration on the pulmonary circulation in rats.

Mechanical properties of the adult pulmonary vasculature are affected by perinatal experience of hypoxic pulmonary hypertension. In the present study, we followed the long-term effects of perinatal pulmonary hypertension induced by means other than hypoxia in rats. Daily injections of indomethacin (1 mg.kg-1 body weight (BW)) were given to the parturient rats. Their newborn pups had significantly increased number of muscularized peripheral pulmonary vessels. Pulmonary hypertension, however, did not persist to adulthood (mean pulmonary arterial pressure (Ppa) was 17.2 +/- 1.3 torr in the experimental group and 16.4 +/- 0.8 torr in controls). Pulmonary hypertension induced in adult rats by exposure to chronic hypoxia or by acute hypoxic challenges was similar in indomethacin-treated and control rats. Normoxic perfusion pressure/flow (P/Q) plots in isolated lungs were less steep in indomethacin-treated than in control rats. Acute hypoxia increased the slope of P/Q plots in indomethacin treated rats but not in controls. The described changes in the pulmonary vasculature induced by indomethacin are similar to those found previously in adult rats born in hypoxia. We conclude that perinatal pulmonary hypertension permanently modifies the pulmonary vasculature.

Animals↗

PubMed1995

[Morphological spectrum of atrioventricular septal defects].

Morphology of atrioventricular septal defect was studied on 73 heart specimens. All of them had a defect of atrioventricular septum and adjoining parts of atrial and ventricular septum, a shortening of inflow parts of both ventricles, a malformation of atrioventricular valves and changed position of aortic valve. There was a great variability of all the studied structures and nearly continuous spectrum of specimens was found as for the ventricles' size, localization and diameter of the defect, communication between atria and ventricles, anatomy of the left ventricle outflow tract as well as the whole atrioventricular valvular apparatus and occurrence of associated heart malformations. A common ostium was formed in 52 cases (71.2%), two separated ostia were found in 21 cases (28.8%) but a continuous transition between both groups was noticed. Both groups showed a great variety of single cusps of atrioventricular valves (in shape, number and anchoring), of papillary muscles and of the size of atrioventricular communication. The finding of frequently associated heart malformations was important from the clinical point of view, especially of the obstructive malformations of the left ventricle. A great morphological variability needs individual surgical solutions, namely reconstruction of valves, closure of septal defects and correction of associated heart malformations.

Endocardial Cushion Defects↗

PubMed1993

[Anomalies in the development of the sinus venosus as a probable cause of heart rhythm disorders and fetal hydrops].

Prenatal ultrasonic examination during the 28th week of gestation revealed a transient disorder of the cardiac rhythm in the foetus. Subsequently repeated echocardiographic examinations confirmed foetal hydrops which together with signs of EP gestosis of the mother was an indication to terminate pregnancy during the 29th week by Caesarean section. In the severely hydropic male foetus in the enlarged anterior wall of the right atrium an atypical vascular canal was found which was in the close vicinity of the sinoatrial node. The latter most probably caused intermittent intrauterine supraventricular tachycardia in a heart with a normal configuration in other respects.

Female↗

PubMed1992

Intranodal "amianthoid" myofibroblastoma. Report of six cases immunohistochemical and electron microscopical study.

Six cases of intranodal amianthoid myofibroblastomas are reported. Immunohistochemically the tumors were actin positive and S-100 protein and desmin negative. Intracytoplasmatic, actin-rich bodies, previously found to be a characteristic feature of this tumor, were identified as cytoplasmatic extensions filled with microfilaments at an ultrastructural level. Abortive vessel formation by the tumor cells and the proliferation of tumor cells centered on veins outside the capsule of the tumor in two of our cases indicated a close relationship between the intranodal palisaded myofibroblastoma and the musculature of vascular origin.

Groin↗

PubMed1991

[Clinical morphology of ventricular septal defects].

The authors give an account of morphological characteristics of different types of ventricular septal defects. They demonstrate their typical pictures obtained by angiocardiographic and echocardiographic examination. The investigation is based on analysis of 295 children with a cinematographically confirmed diagnosis and 75 necroptic preparations of the heart with a ventricular septal defects.

Child↗

PubMed1991

Angiocardiographic diagnosis of ventricular septal defect localization in double outlet right ventricle.

Children with double outlet right ventricle, aged 3 months to 23.5 years, were examined to assess the possibility of angiocardiographic diagnosis of defect localization. It was found angiocardiography allows satisfactory localization of the defect in question. To be able localize the defect, it is critical to determine the interaction between the defect and the conus septum, and the origin of large arteries. To establish the diagnosis of ventricular septal defect, right and left ventriculography in standard and axial projections must be performed.

Abnormalities, Multiple↗

PubMed1990

[The infundibular septum in congenital heart defects. Morphologico-angiocardiographic study of the double-outlet heart ventricle].

The authors investigated the infundibular septum in 40 archival heart preparations with a double outlet right ventricle. They compared the post-mortem findings with the previous angiocardiographic examination and the skiagram of the preparation made post mortem. They present also the corresponding findings obtained by echocardiography. The infundibular septum was in all instances the dominating intracardiac structure influencing the direction of the blood flow from the ventricles into outflow tracts in the direction towards the large arteries. In 15 instances the infundibular septum was shifted in an anterosuperior direction beneath the orifice of the pulmonary artery and it derived the blood current from the left ventricle through the defect in the ventricular septum into the aorta. The restricted blood flow through the aorta led to its hypoplasia, which in 11 instances was associated with coarctation or interruption of the aorta. In seven instances of posteroinferior shift the infundibular septum was straight. These cases were associated with coarctation or interruption of the aorta. In ventricular septum and with stenosis of the pulmonary artery. Based on these findings the authors assume that the shift of the infundibular septum in a double outlet right ventricle has a decisive position as regards haemodynamic manifestations of the defect and in the development of outflow tracts and large arteries. Last not least, information on the infundibular septum is also important for surgery of the defect.

Angiocardiography↗

PubMed1990

[Tracheobronchography in neonates and infants with obstruction of the upper respiratory tract].

In the period of 1980 to 1989 the authors performed contrast examinations of tracheobronchial tree in 38 children up to one year of age, three of them being newborns. In 29 examined children (74.4%) there was an anatomical defect causing the obstruction of upper respiratory pathways. In 15 of them the trachea compression was caused by pressure of hyperplastic thymus on the brachiocephalic arterial truncus crossing trachea. For visualization of upper respiratory pathways Hexabrix 320 (Byk Gulden) was used in 30 children, administered in 10 cases by jet ventilation. The filling was recorded by radiocinematographic method.

Bronchography↗

PubMed1990

[Morphological and angiocardiographic study of atrioventricular septal defects].

A group of post-mortem specimens of 82 hearts with a defect of the atrioventricular septum (atrioventricular canal) was retrospectively examined with special attention to the morphology of the defect in relation to the left atrioventricular anastomosis. In 42 preparations the finding was compared with previous angiocardiography and post-mortally with X-ray pictures of the specimens. Correlation of the findings revealed malformation of the left atrioventricular orifice as part of a complex malformation affecting the valvular apparatus in conjunction with the atrioventricular septal defect. In the very variable anatomical morphology a major part is played by the superior cusp of the left atrioventricular anastomosis. The relationship of the superior cusp to the outflow tract of the left ventricle and to the atrioventricular septal defect has an impact on the variability of the angiocardiographic picture, and last but not least, also on the results of surgical treatment. The anteroposterior, left oblique and hepatoclavicular projections are optimal for visualization of the anomaly.

Adolescent↗

PubMed1989

[Prenatal diagnosis of malformation of the heart using echocardiography].

Fetal echocardiographic findings were compared with autoptic ones in 11 from 22 fetuses and neonates with prenatal diagnosis of a congenital heart malformation. Pregnancy was interrupted on mother's desire in 7 from these 11 cases and completed by delivery in 4 cases. Diagnosed heart anomalies included ectopia (2), double outlet right ventricle with other malformations (2), tetralogy of Fallot (1), complete atrioventricular canal (1), syndrome of visceral symmetry (levoisomerism) with aortic atresia and common atrium as well as ventricle (1) and pulmonary atresia with a dysplastic tricuspid valve (1). Autoptic verification of a broad spectrum of heart malformations diagnosed in utero showed a developing potential of fetal echocardiography. A prenatal diagnosis of malformation enables to interrupt pregnancy in indicated cases. A complete morphological examination has particular demands on pathologist's attitude and training.

Echocardiography↗