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Biomedical subjects

B A Konstantinov

Publications and source records attributed to B A Konstantinov.

At least 19 recordsLinked to original sources
PubMed1997

[Surgical classification of liver local lesions].

There is a variety of liver focal lesions (LFL) and every clinical case should be considered carefully in deciding the problem of indications to surgical treatment. The existing classifications, including the TNM classification, are limited by the peculiar features of liver anatomy. The authors propose an original surgical classification of LFL that combines TNM principles and segmental characteristics of volume of lesion. The classification takes into account intraorganic and extraorganic location of LFL, and marks it by special letter indices. The indication of nosology of LFL in combination with letter and a B digital indices provides the universality of classification. The authors recommend to use the classification in evaluation of malignant and benign liver lesions, as well as alveococcosis and liver trauma.

Humans↗
PubMed1995

[Clinical-functional classification of combined occlusive lesions of the arterial system].

For a complex approach to the clinico-functional appraisal of the vascular system the authors suggest dividing the arterial system into 4 conventional functional basins: the coronary region (1), the brachiocephalic (2), the visceral (3), and the arterial basin of the lower extremities. In accordance with the 4 distinguished anatomo-functional vascular basins, the classification is designated by their first letters: HBVL, where H stands for the heart, B for the brain, V for the visceral vessels, and L for the lower extremities. Next to each letter is shown the functional class of arterial insufficiency of the vascular basin. The figure 0 denotes the absence of arterial stenosis. All the other figures from 1 to 4 reflect the functional severity of arterial insufficiency. The 1st functional class is characterized by the absence of a clinical picture of the disease in arterial stenosis, the 2nd class by the stage of subcompensation of circulation, and the 3rd and 4th classes by decompensation of circulation. The criteria for separating the degree of ischemia into functional classes are suggested. The HBVL classification is a working one because it not only illustrates and indicates fully the condition of arterial circulation in the vessels of the region but determines the tactics of treatment of the patient. The possibilities of the classification are illustrated by concrete clinical cases.

Arterial Occlusive Diseases↗
PubMed1994

[Myxoma syndrome].

The paper provides the follow-up findings of patients with cardiac myxomas according to the presence or absence of the myxomal syndrome. It is shown that it is a multiorgan abnormality wherein the cardiac myxomas that are prone to primarily multiple growth, extraseptal and/or multifocal fixation are associated with the changes in the hypothalamus-pituitary-adrenal and renin-angiotensin-aldosterone systems, skin spotty pigmentation, neoplasms in the viscera, skin, and fat. These specific features emphase the predictive value of the myxomal syndrome, which predetermines that its early diagnosis should be made in routine clinical practice.

11-Hydroxycorticosteroids↗
PubMed1994

Long-term results of plastic reconstructions in acquired aortic valvular disease.

Plastic surgery in acquired aortic valvular disease was performed in 164 patients. Among them, 9 had the isolated aortic valvular injury; 130 mitral-aortic defects; and 25 three-valve injuries. The restoration of the injured valve function was achieved, as a rule, using a combination of surgical methods: commissurotomy or wedge resection of the fibrous tissue in the commissurial area; parietal resection; the aortic root frame plasty; perforation hole plasty; the allogenic valvuloaortic complex sector transplantation; and wedge resection or isometric cusp plication in the commissurial area. Calcinosis was not a contraindication to surgery, if it could be removed completely without the cusp closing function disturbances. The hospital mortality rate was 8%. After hospital treatment all the patients were followed-up: 108 for over 1 year, and the maximum term of the follow-up was 7 years. From 1 to 4 years postoperatively, 4 patients were reoperated due to the appearance of aortic insufficiency. The causes of relapse were: infectious endocarditis (3 patients); active rheumatic process (1 patient); and progressive dilatation of the fibrous ring (1 patient). During the follow-up 8 patients died: 6 of infectious endocarditis with mitral prosthetic injury; and in 2 the cause of death was not clear. The study of immediate and long-term aortic valvuloplasty results based on the clinical experience of 164 operations allows to recommend the elaborated principles of the aortic valve surgical reconstruction for a wide application in cardiac surgery.

Aortic Valve↗
PubMed1994

The mitral valve replacement by the new-type bioprostheses (features of design and long-term results).

The BAKS bioprostheses were created in our centre and they have the following features: (1) to reduce immunogenicity they underwent a combined fermentochemical treatment which resulted in the native xenovalve consisting of collagen and elastic fibres only; (2) in cutting out the valve the natural aortic sinuses were preserved; and (3) the xenovalve was fixed on a functional frame of an original design. From 1979, BAKS have been implanted in 243 patients with the isolated mitral valve reumatic injury. The patients age varied from 11 to 59 years; 91 patients (37.5%) were under 35 years. The 12-year survival rate (without hospital lethality) was 65.5 +/- 5.3%. The most serious longterm complications were: infectious endocarditis (3.14 patients/years); spontaneous degeneration of bioprosthetic cusps (2.24% patients/years); thromboembolism (0.6% patients/years). The morphological examination of bioprostheses removed in reoperations from 10 days to 10 years after implantation was performed in 51 cases. Most often, collagen degeneration occurred in patients under 35. The pathologic structural changes originated because of the localized saturation of bioprosthetic cusps with the recipient plasma proteins, gradual disintegration of collagen fibres, and further calcification of that area. The indications to the mitral valve replacement by BAKS were: the left atrium thrombosis, thromboembolytic syndrome, contraindications to anticoagulation therapy, and the age over 35 years.

Adolescent↗
PubMed1993

[Orthotopic liver transplantation (first clinical experience)].

The article deals with the results of work conducted according to the orthotopic liver transplantation (OLT) program from January 1990 to January 1992. To select the patients for OLT, 54 persons (24 males and 30 females aged from 12 to 55 years) with diffuse (34) and focal (20) diseases of the liver were examined. OLT was indicated for 19 patients who were registered in the waiting list. In the period of waiting for the donor organs, 5 persons died, 3 refused to undergo OLT, and 4 remain on the waiting list. Eight OLT (including one retransplantation) were conducted on 7 patients. The indications for OLT in these patients were: unresectable hepatocellular carcinoma (4), cirrhosis of the liver of viral etiology (1), fulgurant form of hepatitis B (1), transplant rejection crisis which could not be arrested (1). Immunosuppression was conducted by the two- and three-component programs with the use of corticosteroids, cyclosporine A, and azathioprine. Eight crises of transplant rejection were encountered, successful retransplantation of the liver was accomplished for one of two crises which could not be arrested. The survival of the operated on recipients ranged from 3 days to 15 months. Various complications (mainly hemorrhagic and infectious) were encountered in the posttransplantation period. At the time that the article is written, 3 patients are living for 15, 9, and 4 months (after retransplantation of the liver in the last case), their condition is satisfactory. The death of the other recipients was caused by candidosepsis (on the 40th day), polyorganic insufficiency (on the 10th and 3rd days), sepsis (on the 12th day). The results of the liver transplantation program correspond to those of transplantation centers in other countries in the period of OLT mastering.

Adolescent↗
PubMed1993

[Aortic valvuloplasty in acquired valvular disease].

On the basis of the results of studying the morphology, biomechanics, and physiology of the aortic root and the cusps of the aortic valve the authors suggest a substantiated set of surgical manipulations which allow the patient's natural valve to be preserved. Coarse calcinosis of the cusps and fibrous ring of the aortic root is the only absolute contraindication for valvuloplasty. The authors' clinical experience consists of the first 100 operations. Hospital mortality--8.0%. With intraoperative appraisal of hemodynamics, good correction of the abnormality was achieved practically in all patients. The maximal follow-up period by April, 1991 was 5.5 years. During that period four patients were again subjected to operation because aortic insufficiency recurred. The authors recommend their experience with plastic operations on the aortic valve for wide clinical application.

Adolescent↗
PubMed1992

[Intraoperative transesophageal echocardiography in diagnosing left atrial thrombosis in patients with mitral valve disease].

Intraoperative transesophageal echocardiography was conducted in 63 patients with various cardiosurgical pathology (mitral stenosis--43, combined mitral valvular disease--3, mitral incompetence--10, combined mitral-aortal valvular disease--8). Thrombosis of the left atrium was diagnosed in 13 patients. Transesophageal echocardiography in 38 patients revealed spontaneous echo-contrasting of blood currents in the cavity of the left atrium. Statistical analysis showed this sign to be characteristic of mitral stenosis complicated by thrombosis of the left atrium (p < 0.001). Transesophageal echocardiography allows visualization of thrombi of small diameter (1.0-1.5 cm). Specificity of the method is 100%, sensitivity 87%.

Adult↗
PubMed1991

Extracorporeal mechanical pulsatile pump and its significance for myocardial function recovery and circulatory support.

The authors performed 12 acute (on dogs) and 12 chronic (on calves) assisted circulation experiments with the use of the total extracorporeal mechanical pump (TEMP) artificial ventricles. The functional morphological research of the myocardium suggests that in addition to the possibility of the biological heart function full replacement, the artificial ventricle also helps recover damages in both the myocardial infarction and distal zones. The critical time period up to the onset of artificial circulation is not more than 2 h, and after that myocardial changes are irreversible.

Animals↗
PubMed1991

Total artificial heart without valves: principles of design and implantation technique.

A total artificial heart (TAH) without valves is a TAH of a new design. The entry and exit are combined in one opening. The excision of the biologic ventricles is below the atrioventricular groove, while the outlet and position of the right and left ventricles are preserved. The aortic and pulmonary valves have been left intact. Bioprostheses BAKS are implanted into the mitral and tricuspidal positions. Initial experiments hold much promise: the absence of artificial valves decreases the risk of thromboemboly; the natural heart basis remains intact, which facilitates the subsequent donor heart transplantation; and the work of the new TAH is practically noiseless.

Bioprosthesis↗
PubMed1991

[Surgical aspects of radical correction of tetralogy of Fallot].

The article deals with the analysis of variant anatomy of Fallot's tetralogy due to hypoplasia of the pulmonary trunk on basis of morphometric and intraoperative examination of 141 patients 4 to 43 years of age (15.3 +/- 3.26) who underwent radical correction of the anomaly; 48 (34%) of these patients were operated on after various palliative operations. On grounds of detailed study of the variants of the relations of anomalies of the cardiac anatomical structures in Fallot's tetralogy the authors elaborated operative proceedings by means of which mortality after radical correction fell to 6.5%.

Adolescent↗
PubMed1991

[Heart transplantation conducted at the All-Union Research Center of Surgery (the first clinical experience)].

The authors analyse experience in the first eight operations for orthotopic transplantation of the heart. Six patients were discharged from the clinic with good immediate results. Comparison of their own data with summarized results gained in other countries allowed the authors to define some specific problems which are of practical interest for clinics embarking on the clinical realization of the problem of heart transplantation.

Adult↗
PubMed1990

[Atrioplasty in surgical correction of mitral valve defect complicated by left-sided atriomegaly].

Surgical treatment of 40 patients with mitral valvular diseases and left atriomegaly is analysed. The dimensions of the giant left atrium in this group of patients must be reduced because it causes compression of the posterobasal part of the left ventricle, constriction of the lumen of the left main bronchus or compression of the inferior and middle lobes of the right lung. Left atrioplasty has a favorable effect on the course of the immediate postoperative period and reduces significantly hospital mortality among this grave contingent of patients.

Adolescent↗
PubMed1990

[Mitral valve prosthesis with preservation of the chordae and papillary muscles in patients with mitral insufficiency].

Mitral valve (MV) prosthetics was performed in 14 patients in its insufficiency. In MV replacement the chordopapillary apparatus (CPA) of the posterior cusp was left intact. The EMIKS or LIKS disk prosthesis was implanted in most cases (6 and 6 patients, respectively), the biological BAKS prosthesis was implanted in 2 patient. Orientation of the large semicircumference in the direction of the anterior or posterior commissure was the optimal orientation for the disk prostheses. Measurement of the parameters of hemodynamics on the operating table showed that reduction of the rigidity of the left-ventricular myocardium and the increase of the stroke index in patients with an intact chordopapillary apparatus of the posterior cusp differed significantly from those in patients with completely excised MV. Preservation of the CPA during MV replacement in patients with mitral insufficiency leads to reduction of the rigidity of the left-ventricular myocardium and improvement of its function immediately on the operating table.

Adolescent↗
PubMed1990

[Effect of preserved subvalvular apparatus on regional left- ventricular function after mitral valve prosthesis in patients operated on for mitral insufficiency].

Mitral valve replacement with preservation of the chordo-papillary apparatus of the posterior mitral cusp was done in 24 patients with mitral valve incompetence. In nine patients, in addition to the conventional flow manometry, myocardiography was performed to study regional left ventricular myocardial contraction. For comparison, nine other patients were examined, who had been operated on for mitral valve incompetence by conventional mitral valve replacement with total resection of all its supravalvular structures. A significant difference in the improvement of left ventricular myocardial contraction was seen in patients with preserved chordo-papillary apparatus as compared with the other group. Improvement of the contractile function is believed to be secondary to enhanced myocardial compliance during the relaxation phase, rapid filling and pre-ejection. Enhanced compliance may be a factor governing the left ventricular myocardial performance.

Chordae Tendineae↗
PubMed1990

[Causes of mitral valve re-stenosis and the ways of its prevention].

The authors evaluated comparatively the results of surgical treatment of mitral stenosis in 203 patients after open mitral commissurotomy (OMC) (their personal experience) and the literature data concerning 168 patients who underwent closed mitral commissurotomy (CMC). The frequency of mitral stenosis recurrences with the use of both methods was determined. OMC was on a par with CMC in safety and exceeded it in efficacy. The frequency of mitral restenosis was considerably lower after OMC than after CMC (p less than 0.05). The authors claim that the main cause of mitral stenosis recurrences is residual stenosis developing in inadequate correction of the anomaly, while the principal preventive measure is OMC which makes it possible to separate the fused commissures completely, remove the subvalvar adhesions, and restore the mobility of the cusps.

Humans↗