PubMed Health⌕ Search

Biomedical subjects

J Hruda

Publications and source records attributed to J Hruda.

At least 37 records · Page 2Linked to original sources
PubMed1993

[Long-term follow-up of the quality of life in children after surgery for vascular compression of the respiratory tract].

The aim of this study is the analysis of long-term results of surgery for vascular airway compression. Out of those operated within last 14 years at our institution, thirty two have a longer than five years follow up, being now 9.1 +/- 3.0 years following surgery. All are in excellent clinical condition. One quarter of patients show occasional stridor and one third frequent respiratory infections. Eighty percent have some lung function abnormality, 72% features of central airways obstruction. Pulmonary perfusion scintigraphy demonstrated in 19% asymmetric pulmonary blood flow. Magnetic resonance imaging showed relationship between vessels and airways. Although long-term outcome of surgery for vascular airway compression is excellent, high percentage of pathologic lung functions is of concern and substantiates the need for close long-term follow-up.

Aorta↗
PubMed1993

[Magnetic resonance imaging of the postoperative status in children with congenital heart defects].

The justification of examinations by magnetic resonance and the results of visualization of cardiac and vascular structures in relation to the performed surgical operation were evaluated retrospectively in 24 children after surgery of congenital heart disease. Thirteen patients had an operation of coarctation or a double aortic arch and four had an operation of an anomaly of the branch of the pulmonary artery-its loop or atresia. Seven patients had operations, mostly complicated inborn heart disease, of the common arterial trunk and transposition of the large arteries with a conduit, tricuspidal atresia after Fontan's or Glenn's modified operation and ligature of an aortal aneurysm. At the time of examination the patients were 4 to 18 years old. Spin echo sequences obtained by basic reconstructions of T1 and possibly T2 weighted images on a 1.5 T Magnetom apparatus Siemens proved an excellent visualization in the area of the large arteries and the capacity of detailed visualization of cardiac structures, incl. changes of the vascular wall in relation to the performed operation. Magnetic resonance examinations provided accurate information on central anastomoses and conduits as well as on changes of the vascular lumen. The investigation confirmed that magnetic resonance is suitable for visualization of postoperative changes and findings of morphological structures in particular at sites of cardiovascular anastomoses where magnetic resonance supplements the visualization capacity of echocardiography and substitutes invasive examinations where only an angiographic examination is needed. In eight instances the examination was supplemented by invasive assessment of haemodynamic conditions.

Adolescent↗
PubMed1992

Intermediate to late results of surgical relief of vascular tracheobronchial compression.

Since 1979, a total of 69 infants and children aged 0.1 to 11.9 (median 0.7) years required surgical intervention for: double aortic arch (26), anomalous origin of innominate artery (26), right aortic arch with left ligamentum arteriosum (9), pulmonary artery sling (5), retroesophageal right subclavian artery (3). Before operation, the morbidity was high: 84% of children were symptomatic in the first trimester of life with 24 patients requiring mechanical ventilation. Seven children had an accompanying heart defect. Left thoracotomy was the preferred approach. There were 2 early (asphyxic brain damage, postoperative pneumonia) and 2 late (tracheomalacia, complex heart defect) deaths. Five patients (2 originally operated elsewhere) needed reoperation for persistent symptoms. All 65 survivors are well 1 month to 11.9 (mean 3.9 +/- 3.62) years after surgery. Tracheobronchoscopy, magnetic resonance imaging, and lung function testing were helpful for postoperative evaluation. Minor tracheal compression was revealed in 4 patients despite their good clinical condition.

Airway Obstruction↗
PubMed1992

Effect of prostaglandin E2 on the ductus arteriosus in the newborn rat. An ultrastructural study.

A patent ductus arteriosus (DA) was maintained in newborn rats (Wistar strain) by administering prostaglandin E2 (PG E2) in doses of 15 micrograms.kg-1 at 30 min intervals up to 300 min after birth. In the control animals, the DA was functionally closed 300 min after birth. The lumen was blocked by clustered endothelial cells at various stages of degeneration. Elastic membranes of the media had disintegrated into irregular fragments and the smooth muscle cells were contracted. Cytoplasm excrescences formed on their surface as a result of contraction protruded as hernias into adjacent muscle cells and into endothelial cells. The smooth muscle cells degenerated. The administration of PG E2 inhibited contraction of the smooth muscle cells and so also the development of degenerative changes; 300 min after birth the DA was fully patent, the elastic membranes were structurally intact, regularly organized and continuous. The smooth muscle cells had the character of synthesizing cells with richly developed granular endoplasmic reticulum. The intima and its endothelial lining were likewise free from structural changes. The ultrastructural image of the wall of the DA correspondent to the state 10 min after birth, when the DA was fully patent. The administration of PG E2 did not induce any ultrastructural changes indicative of injury to the wall of the DA.

Animals↗
PubMed1990

[Surgical treatment of congenital vascular anomalies causing tracheoesophageal compression].

Forty four children underwent surgery for congenital vascular anomalies causing tracheal compression in Kardiocentrum--Motol during last ten years. Double aortic arch was encountered 18 times, tracheal compression by the innominate artery in 12 instances, right aortic arch with left ligamentum arteriosum and possibly aberrant left subclavian artery 7 times, pulmonary artery sling in 5, finally aberrant right subclavian artery twice. The age of the children was 2 weeks to 11 years (median 6 months). Stridor was present in 38 infants under 3 months, 17 children with severe dyspnoea had artificial ventilation or were resuscitated or hospitalized at the intensive care department. In four an associated cardiac defects was present. The diagnosis was made by oesophagography, echography, laryngotracheoscopy, in the majority of children it was confirmed by angiography of the sometime with tracheobronchography. The operation was performed in 41 children from left-sided thoracotomy, the vascular ring was released by resection or retraction of the compromising vessel and connective tissue from the trachea. Serious stenosis of the distal trachea in one patient found before operation persists one year after operation, the patient breathes through an individual tracheostomic cannula. Four children could not be extubated for prolonged periods after operation, they were re-operated, the annulus was released. Three patients died, one from bronchopneumonia during the postoperative period, the second one from hypoxic brain damage and the third one after operation of a complex heart disease. In 40 children satisfactory long-term results were achieved, the operation resolved respiratory complaints. The prerequisite of satisfactory results in an accurate diagnosis, early indication of the operation and a perfect surgical operation and good postoperative care.

Aorta, Thoracic↗
PubMed1990

[Pneumococcal infectious endocarditis in an infant (case report)].

In a 10-month-old infant with purulent pneumococcal meningitis without structural heart disease acute infectious endocarditis developed. Echocardiographic examination revealed vegetations on both cusps of the mitral valve. With regard to the age and critical condition of the infant, in the acute stage surgical removal of the vegetations, was not indicated. During long-term intravenous antibiotic therapy the vegetations on the mitral valve and clinical and laboratory manifestations of endocarditis disappeared. The valve was, however, devastated and the child developed severe mitral insufficiency. Because of progressive cardiac failure which could not be controlled by drugs, at the age of 19 months a plastic operation of the mitral valve had to be performed after which the haemodynamics and clinical condition improved markedly.

Endocarditis, Bacterial↗
PubMed1989

[Cardiac arrhythmia following total correction of tetralogy of Fallot].

41 patients after surgical correction of the tetralogy of Fall of aged 2-24 years (mean 11.2 y.) were followed for 12-65 months (mean 39.5 m.) for known or suspected dysrhythmias. 24-hour ambulatory ECG and exercise testing demonstrated nonsignificant ventricular ectopy (grade 0-1 according to a modified Lown classification) in 28 patients (group I) and significant (grade 2-5) ventricular dysrhythmias in the remaining 13 patients (group II). There were 2 cases of sudden late death in group II, whereas all patients in group I are alive. The victims of sudden death had no, other serious dysrhythmias and received no antiarrhythmic treatment. Ejection fraction of the functional part of the right ventricle estimated by radionuclide angiocardiography was not different in both groups whereas, global right ventricular ejection fraction differed nearly significantly (group I: 39.6 +/- 8.3%, group II: 31.9 +/- 10.4%, p = 0.052). Thus, a diminished global right ventricular ejection fraction caused by an extensive resection and large patch in the right ventricular outflow tract may be connected with the occurrence of higher grades of ventricular ectopy. These may lead to sudden late death.

Adolescent↗
PubMed1989

The physiological closure of ductus arteriosus in the rat. An ultrastructural study.

The evolution of morphological changes in the wall of the ductus arteriosus during its physiological closure in newborn rats was examined by electron microscopy. The contraction of smooth muscle cells in the tunica media seems to be the primary mechanism which leads to the physiological closure of the ductus arteriosus. For this reason our attention was centred mainly on the morphology of the tunica media. No important changes in the ultrastructure of smooth muscle cells can be observed in the early phases of the closure. Most of them exhibit ultrastructural features of cells with enhanced synthetic activity during all phases of the closure. The permanent contraction of smooth muscle cells results in their morphological changes. The most striking is the herniation of smooth muscle cell cytoplasm into the endothelial and later into adjoining muscle cells. These changes together with signs of degeneration of the smooth muscle cells are already clearly discernible 120 min after birth. The elastic component of the tunica media exhibits surprisingly fast changes. As soon as 60 min after birth, the fragmentation of elastic membranes and their structural changes provided evidence about the degradation of elastic material. The matrix vesicles, probably derived from the lysosomal apparatus of the muscle cells, may play an essential role in this process.

Animals↗
PubMed1989

Effect of the administration of prostaglandins (PGE2) in the early postnatal period on closure of the ductus arteriosus in the laboratory rat.

Maintenance of a patent ductus arteriosus by means of prostaglandins enables the surgical correction of a congenital heart defect in infants to be postponed until a phase of development when the operation hazards are smaller. We investigated the pathophysiological consequences of this therapeutic measure in an experimental model in which E2 prostaglandin was administered to newborn laboratory rats. It was found that, physiologically, the ductus arteriosus (DA) closed progressively within 180 min after birth. The repeated administration of PGE2 (subcutaneously, 15 micrograms.kg-1 every 30 min from the 5th min after birth) blocked closure of the DA, which was still fully patent 300 min after birth. Histological tests showed no significant differences in the structure of the tunica media of the physiologically patent and the PGE2-treated DA. The results show that PGE2 also inhibit physiological closure of the DA in newborn rats. Long-term study of this pathophysiological process is at present impeded by the need for the continuous administration of prostaglandins.

Animals↗
PubMed1989

[Surgical treatment of aorto-ventricular tunnel].

The authors give an account of their experience with the treatment of aortoventricular tunnel and describe a successful operation in a four-month-old infant. They emphasize the importance of early indication and accurate surgical technique to preserve satisfactory function of the aortic valve.

Aorta, Thoracic↗