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Biomedical subjects

L S Barbarash

Publications and source records attributed to L S Barbarash.

At least 37 records · Page 2Linked to original sources
PubMed1985

[Dynamics of the phonocardiographic picture following the bioprosthesis of the mitral valve].

Patterns of phonocardiographic changes were studied in 67 patients (aged 20 to 51 years) with acquired mitral disease 2 months to 6 years after the implantation of aortic xenobioprostheses, preserved in glutaraldehyde and mounted on a hard or flexible support. Phonocardiographic findings were compared with intracardiac hemodynamic data. Three stages and three types of phonocardiographic pattern were identified in patients with normally functioning xenobiovalves. As the postoperative period grew longer, the patients showed progressively smaller amplitudes of tones I and II, a smaller, if any, systolic output murmur and diastolic murmur; some patients no longer exhibited the prosthetic opening tone. PCG parameters showed stability between 2 and 6 years of follow-up.

Adult↗
PubMed1985

[Effect of heart valve prostheses on hemolytic processes in patients with acquired heart diseases].

Parameters of intravascular hemolysis (erythrocyte count, hemoglobin concentration and circulating blood volume, acid erythrograms, plasma free hemoglobin and haptoglobin levels) were examined in 44 patients with acquired heart diseases controlled with the aid of bioprostheses. As shown by 2 years' follow-up, successfully implanted mitral and aortal bioprostheses did not significantly affect the activity of intravascular hemolysis. Yet developing stenosis and incompetence of the bioprostheses may be accompanied with a significant intravascular hemolysis.

Adult↗
PubMed1985

[Mechanisms of mineralization of aortic xenograft bioprostheses in young patients].

The results of mitral valve replacement with aortic xenobioprostheses in 15 patients, aged 14 to 20 years, are presented, the follow-up reaching 7 years. The bioprostheses functioned normally 1.5-2 months after the operation. Within three months to 5 years following the operation, 6 patients developed a bioprosthetic dysfunction that caused death in 4. Histologic and ultrastructural examination revealed signs of tissue destruction and calcinosis that were confirmed by roentgenologic and biochemical findings. The pathogenesis of calcification and tissue destruction of xenobioprostheses is discussed.

Adolescent↗
PubMed1984

[Remote results of the correction of mitral valve defects with aortic xenobioprosthesis].

An analysis of the 6-year observations of 84 patients with aortal xenobioprosthesis in the mitral position has shown the bioprostheses to give an adequate and stable correction of hemodynamics, low risk of thromboembolic complications. The anticoagulation therapy was found to be not necessary in most of the patients. The aortal xenobioprostheses in patients older than 20 gave high survival rate (93%) and low risk of specific complications (5,4%). However, great amount of complications in young patients (58%) shows them to be used but for strict indications.

Adolescent↗
PubMed1978

[Effect of preservation with metaperiodate and glutaraldehyde on the immunogenic properties of vessels].

Experiments were conducted on guinea pigs and rabbits. It was shown that treatment of human femoral vessels with metaperiodate and glutaraldehyde solutions led to a sharp (10-fold) reduction of the amount of water-soluble proteins in the tissue homogenates, to a decrease of the sensitising and anaphylactic activity of the extracts, to inertia in the precipitation test with homologous antiserum to crude tissue.

Aldehydes↗
PubMed1978

[Results of implanting aortic valve xenografts into the tricuspid position].

From 1968 to 1976 transplantation of the tricuspid valve was performed on 47 patients with combined form of rheumatic heart disease. Hospital mortality was 36%. The follow-up period in 30 cases ranged from one to 7 1/2 years. Ten patients died in the late postoperative periods, only in one of them the cause of death was associated with incompetence of the transplanted valve. According to the findings of dynamic clinical follow-up, the function of the transplant in the other patients was quite satisfactory; at the same time, peculiarities of the phonocardiographic picture of valves treated by different methods were revealed.

Adult↗
PubMedDate not supplied

[Three-dimensional visualization of low-field MRI data using personal computer].

An experience of three-dimensional reconstruction of low-field MRI data using a modern personal computer and Windows software is presented. A value of volume visualization in routine diagnostics and areas of its effective use are shown. Pulse sequences best suitable for volume reconstruction are selected. Performance of high-end PC in visualization of medical data is evaluated.

Humans↗
PubMedDate not supplied

[Validation of support frame parameters for aortic valve xenograft bioprostheses].

The techniques of determining the supporting structure dimensions are analyzed. The shortcomings of the available techniques based on the measurements of the aortic roots when they are under internal pressure are emphasized. Some errors inherent to techniques commonly used to determine the mobility of the base ring of the aortic valve are demonstrated. Our study as well as analysis of the published data make it possible to draw a conclusion that the ring of the supporting base can be round and rigid in the radial direction.

Aortic Valve↗
PubMedDate not supplied

[Functional characteristics of flexible supporting structures for heart valve bioprosthesis].

Hydraulic characteristics of heart valve bioprostheses mounted on supporting structures of various rigidity have been studied under physiologic conditions. An actual mobility of the supporting structures made of different polymers is determined. Static and dynamic components of the support displacements have been shown to develop as the bioprosthesis is under the load, the dynamic component being strongly dependent upon the rigidity of fastening the bioprosthesis on the axis. It is noted that considerable improvements in hydraulic characteristics of bioprostheses are achieved through the use of flexible supporting structures.

Biomechanical Phenomena↗