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The authors have designed a pneumatic drive, which differs from the known ones in that it contains two electromagnetic two-linear and two-positioned air distributors while the motor operates in the mode excluding the change of its axis direction. This affords using a standard crank mechanism as a transformer of rotary motion to translational motion and reducing several times the power consumed. Besides, the two-linear and two-positioned air distributors allow a possibility of exercising a separate control over the time of the systole-diastole phases of the left and right ventricles. In this case both ventricles can work at 100% filling whereby maintaining the capacity of the artificial heart without additional energy consumption.

The article discusses the first clinical experience of the donor maintenance of the program of heart transplantation. Under analysis are etiology and terms of the process of death of the brain in 65 potential donors. The authors propose a scheme of the three-stages assessment of fitness of his heart for transplantation. Specific features of intensive therapy of the donors are considered. Twenty donors were used for clinical transplantations of the heart, in 18 cases (90%) satisfactory recovery of functions of the transplanted heart was noted.

This report summarizes 1) features of the local redistribution of calcium ions and formation of complexes with calcium (Ca) in the presence of polymer samples; 2) the adsorption of Ca ions and Ca containing complexes onto biomaterial surfaces; 3) the character and composition of Ca containing deposits; and 4) the role of cellular and humoral factors in calcification. All experiments were done with three types of medical grade polymer material (from USSR): silicone rubber (SR), polyurethane "Vitur" (PU), and polyethylene (PE). Biochemical, radioisotopic, SEM, and EDAX methods were used in in vitro and in vivo experiments. The diffusion chamber model was used in animal experiments. SR was shown to induce greater changes in complex formation processes and to adsorb more Ca containing complexes than PE or PU. In addition to the degree of SR calcification seen after 21 days, implantation accentuated these findings. The possibility of calcification of polymer materials without direct contact of material and cells was observed. Combining the in vitro and in vivo experimental data, the authors propose a hypothetical scheme of biomaterial calcification.

The authors discuss three various methods of initial hypothermic perfusion applied in 160 donors. The function of the donor kidneys was evaluated according to the results of clinical transplantation. The advantage of high-current perfusion in situ is shown, it allows the number of donor kidneys which are unfit for transplantation to be reduced to minimum. The method of in situ perfusion of organs in multiorganic collection ensures the most adequate antiischemic protection of all organs removed for transplantation, particularly in donors after circulatory arrest.

It is suggested that differentiated electrocardiography widens the possibilities of routine electrocardiography as it enables to perform not only qualitative analysis but also to evaluate changes of the repolarization phase quantitatively. Differentiated electrocardiography makes it possible to distinguish acute myocardial infarction from other forms manifested on the ECG as negative waves.

The results of hemoperfusion through a suspension of cryoconserved hepatocytes in 21 patients with severe hepatic insufficiency are analysed. It is shown that the manipulation had a beneficial effect on the clinical and biochemical indices, which was manifested by diminished jaundice and skin pruritus, increased physical activity, improved appetite; reduced levels of bilirubin, transaminase, alkaline phosphatase, bile acids, and cholesterol. The information gained is evidence that the method can be included in the complex treatment of patients with severe hepatic insufficiency.

An analysis was made of the work carried out by the Department of Coronary Surgery and Heart Transplantation as regards heart transplantations during 1988. As many as 119 patients, hypothetical heart recipients, received medical advice. The Department refused hospitalization to 42 patients because of the nonconformity to the indications and contraindications to heart transplantation. 77 patients were admitted to the Department. During examinations and treatment, 53 persons were discharged from hospital. 8 patients died before donor's hearts were received. Donor's hearts were transplanted to 10 patients. 3 persons died from severe infectious complications on days 12, 15 and 43 after the operation. Following the operation 7 patients have been surviving from 4 to 17 months. The patients' status remains satisfactory. The functional parameters of the donor's heart are within normal. Taking into consideration the lack of the treatment methods for patients with terminal heart lesions, it is necessary that the number of operations be increased. A great importance in this case is attached to the joint efforts of internists and cardiologists, aimed at the screening and examination of potential heart recipients.

Experiments were conducted on 26 mongrel dogs and 10 calves to evaluate the effect of uni- and biventricular bypass created by means of artificial heart ventricle on hemodynamics in acute cardiovascular insufficiency (ACVI) and heart arrest (HA). The use of unilateral right-ventricular (RVB) and left-ventricular bypass (LVB) was shown to be equivocal: in sufficient functional reserve of the left-ventricular myocardium the volume blood flow in the aorta was increased to a greater degree by RVB (to 2.1 +/- 0.3 l/min) than by LVB (to 2.0 +/- 0.5 l/min). Experiments during HA allowed the authors to evaluate selectively the bypasses in maintenance of the systemic blood flow. It was found that in univentricular bypass the other half of the heart had an effect on hemodynamics, which depended on the initial hemodynamic parameters of the divisions of circulation with high and low pressure, the filling of the heart cavities with blood, and the effect produced through the interventricular septum. The increase of the volume blood flow in the aorta in RVB to 0.6 +/- 0.1 l/min is linked to a great measure by the authors with the conducted artificial ventilation of the lungs. It was noted that the greatest difficulties in maintaining the systemic blood flow in ACVI were associated with the development of disproportion of the contractile function of the right and left parts of the heart. With consideration for this circumstance, the indications for univentricular bypass are determined. A clinical case with prolonged use of LVB (8 days) is discussed.

The article analyses the first clinical experience in orthotopic allotransplantation of the heart at the Scientific Research Institute of Transplantology and Artificial Organs, USSR Ministry of Health, in the period from October, 1986 to July, 1989 (26 transplantations of the heart and one two-stage transplantation of the heart with the use of "Poisk-10M" artificial heart for 3.5 days in the first stage). Eleven patients are alive. Follow-up periods: maximum over 2.5 years, minimum 3 months. Sixteen patients died in different periods (up to 12 months). Three-component therapy (cyclosporine A, methylprednisolone, azathioprine) was applied for immunosuppression. The authors analyse the problems of the selection of potential recipients (indications and contraindications) and donor, the optimum surgical techniques, complications of immunosuppressive therapy, and infectious complications. The first clinical experience in two-stage transplantation of the heart is analysed. The first experience in transplantation of the heart in patients allows the conclusion that the use of this method for the management of the terminal stage of congestive cardiac insufficiency is a reality.

The article discusses the results of applying for the first time Soviet-made "Modul" and "Yasen" artificial ventricles of the heart (AVH) in a left ventricular bypass regimen in patients with refractory cardiac insufficiency. Improvement of AVH design and rational tactics of attendant drug therapy allowed the period of the safe application of the AVH in the organism to be increased to more than 8 days.

An atomic artificial heart for orthotopic implantation was developed with the following characteristics: volume, 1.2 L; weight, 1.5 kg; radioisotope power, 45 W; operating life, up to 5 years; hemodynamics, similar to natural hemodynamics. The artificial heart includes a thermal drive with systems for regulating power, feeding steam into the cylinders, return of the condensate to the steam generator, and delivery of power to the ventricles and heat container. The artificial heart is placed in an artificial pericardium partially filled with physiologic solution. It uses a steam engine with two operating cylinders that separately drive the left and right ventricles. There is no electronic control system in the proposed design. The operation of the heat engine is controlled, with preservation of autoregulation by the vascular system of the body. The separate drives for the ventricles is of primary importance as it provides for operation of the artificial heart through control of cardiac activity by venous return. Experimental testing on a hydromechanical bench demonstrated effective autoregulation.

Experiments were conducted on dogs; a study was made of the influence of a method of assisted circulation--contrapulsation, on the myocardial ultrastructure. A sharp glycogen accumulation in the muscle cells of the heart, the presence of mitochondria with a marked osmophilic microgranular matrix, and also a high pinocytic activity of the capillary endothelial cells were revealed by electron microscopy. The data obtained pointed to the metabolic reconstruction in the myocardium, and primarily to the reduction of the energy level of the myocardial muscle cell function. The changes in the myocardial ultrastructure revealed apparently provided the positive therapeutic effect.

A possibility of the artificial ventricle regulation using information on the atrial contraction is discussed. Correlations between atrial wall tension and ventricle tension as well as the pressure under radom heart rhythm variations were studied. The wall tension of the appropriate heart portion was recorded by the arched tensiometers, and intraventricular pressure under cavity catheterization by the electric manometer. The cardiac rhythm varied between 2.0 c-1 and 4.0 c-1. A correlation between the tension and interpulse interval, (correlation coefficient being 0.62 +/- 0.05) was established. The close relationships "atrial wall tension-intramuscular pressure" were observed. For such relationships the correlation coefficient changed from 0.713 +/- 0,09 to 0,874 +/- 0.02 depending on the average value of interpulse interval. It is concluded that the information on the atrial contraction can be used for artificial heart regulation.

Data obtained from epidemiological studies carried out in some large administrative regions have shown that among the causes of socially dangerous actions committed by schizophrenics the syndromes with prevalent delusional and hallucinatory-delusional disorders take the second (after psychopathy-like states), and, as regards acts of violence, the first place. Practically all the phenomena of a delusional or a hallucinatory-delusional syndrome may be the motives of the socially dangerous actions. However, the occurrence and character of those actions are different, these differences being associated with particular psychopathological features of the hallucinatory-delusional syndromes. The knowledge of those peculiarities may contribute to early recognition of such patients and to taking adequate curative and rehabilitation measures aimed at preventing the dangerous actions.

The development of autonomous systems for the artificial heart (AH) and for circulatory assistance (CA) has taken several directions. Studies relating to one direction--the development of paracorporeal and implanted systems based on thermal or electric motors--have been conducted at our institute in two stages, moving from stationary systems to totally implanted systems for long-term use. The development of these systems is described. Improvements in the linear solenoid motor, used in some of the first paracorporeal systems, enabled progress toward the development of implanted CA systems based on a reversing electrohydraulic actuator. Modifications were also made in the control system. Early animal testing of these systems indicated that they could be effective in unburdening the heart cavities during left and right bypasses. Full implantation, however, demanded that the devices have improved forms and dimensions and less weight. Smaller electromechanical systems are being developed, and we are experimenting with ways to increase the overall autonomy of the system. An orthotopic model of an implanted AH is promising. Experiments continue on the use of the body's own skeletal muscles to create a blood pump.

On the basis of an epidemiological multifactorial comparative study of schizphrenic patients who committed and did not commit socially dangerous acts, in several large administrative territories it was possible to detect a distinct correlation of different types of dangerous acts with clinical symptoms of the disease. The study contains a list of syndromes and their variants conjugated with different frequencies of dangerous acts. It was established that schizophrenic patients most frequently commit dangerous acts when there is a predominance of psychopathlike disorders in the clinical picture, mainly of a polymorphic and explosive character. It was demonstrated that this circumstance should be taken into consideration along with other factors, in a comprehensive assessment of the risk of a commitment of socially dangerous acts by patients.

In valve replacement operations on 78 patients with acquired heart disease, the efficiency of phosphocreatine in intraoperative protection of ischemic myocardium was evaluated by clinical, morphologic, and biochemical methods. Phosphocreatine (8 to 10 mmol/L) in a blood cardioplegic solution was used in operations on 41 patients; in the control group (37 patients) standard blood cardioplegia was used. In the group with phosphocreatine treatment we observed more rapid recovery of hemodynamics after release of the aortic cross-clamp, a decreased frequency of fibrillation, and more frequent restoration of sinus rhythm even if there were sinus rhythm disturbances before aortic cross-clamping. Analysis of the biopsy samples taken from the right ventricle showed protection of the sarcolemma against ischemic damage afforded by phosphocreatine and complete preservation of high-energy phosphates. The results obtained confirm the conclusion made by Robinson, Braimbridge, and Hearse (J Thorac Cardiovasc Surg 1984; 87:190-200) that phosphocreatine is an effective additional cardioprotective agent when used in cardioplegic solutions.

The paper presents a generalized experience in the surgical treatment of patients with frequent attacks of paroxysmal tachycardia associated with additional cardiac conduction pathways, that are not affected by the drug treatment. The results are described of 27 operations of destruction of anomalous cardiac conduction pathways. The use of a special ultrasound destructor permits the surgeon to perform the operation on the functioning heart, thus providing maximal radical surgery with minimal cardiac trauma and best effects.

The article gives the analysis of the authors' experience in developing the systems of mechanical maintenance of blood circulation: AvIK-9M, Sinus-BK, and the cylinder pump with an additional distal chamber, which has not only high hemodynamic efficiency but also, to a considerable extent, improves the bioenergetics of the myocardium. It also gives a detailed description of the device for the retrograde counterpulsation and periodic occlusion of the coronary sinus. All the systems have successfully undergone testing by experiment and in the clinic.

The authors stress the importance of reactions associated with the concentration of biologically active substances in the body tissues, in particular their influence on the contractility and escitability of the heart muscle. They cite the results consequent upon a study on the catecholamines and acetylcholine content in the myocardial tissue of the left ventricle and left auricle of the heart before and after institution of an auxilliary circulation effected with the aid of a valveless pump connected to the subclavicular artery in 22 dogs. An analysis of the results demonstrated that by producing counter-pulsation with the pump the concentration of catecholamines and acetylcholine in the tissues of the left head diminishes, but the fall of the catecholamines concentration does not reach the level typical of cardiac insufficiency. The authors believe that investigations of this kind may help elaborate optimal conditions and a permissible duration of the auxilliary circulation.

Results of haemosorption in treating digitalis intoxication are analyzed. In 2 patients haemosorption was used for 90 min at the volume speed of 100 ml/min. Digoxin clearance at the start of haemosorption was 98.4 and 83.8 ml/min, at the end 85.7 and 70.3 ml/min. Digoxin concentration decreased by 44.8 and 13.0%. Hemosorption enabled performing electric defibrillation with restoration of the sinus rhythm.

Forty-four patients with acute myocardial infarction were given 0.15 mg/kg propranolol (obsidan) by intravenous drip, after which 80--160 mg of the drug were given daily by mouth for 4--5 days. The extent of the ischemic damage and the dynamics of the infarction zone were judged according to the results of electrocardiotopogram recorded from 35 leads and serial tests for creatine phosphokinase activity in blood serum. The hemodynamic shifts occurring under the effect of the treatment were determined in the same patients. The results were compared with those in a control group (37 patients) identical in clinical and hemodynamic signs. It is established that obsidan given by the schedule proposed reduces significantly the electrocardiographic signs of ischemic damage to the myocardium (according to the ST segment) and the spread of the zone of necrosis in the first days of the follow-up. This is attended by deceleration of the cardiac rhythm and a decrease in systemic arterial pressure and cardiac output. The hemodynamic shifts occur within the ranges of admissible fluctuations and do not cause circulatory insufficiency as a rule.

Experiments were conducted on rabbits. A study was made of peculiarities of blood coagulation and of the functional changes in platelets at the period of the thrombus organization, and also at various stages after its formation in the femoral vein. It appeared that at the period of the thrombus formation and during the first 5 minutes after its organization there occurred hypercoagulation changes in the blood and hypocoagulation of the plasma against the background of decrease in fibrinogen, hyperfibrinolysis, hyperheparinemia and thrombocytopenia. One to three days after the thrombosis of the femoral vein the blood hypercoagulation capacity becomes less pronounced. At this time thrombocytosis, an increase in fibrinogen content, hypoheparinemia and inhibition of fibrinolysis are observed. In the authors' opinion, hemocoagulation changes in venous thrombosis were chiefly caused by the hypercoagulation activity of the blood formed elements.