scholarly journals First experience in implantation of a mechanical circulatory support device based on a disk-type pump: an acute experiment

2020 ◽  
Vol 22 (2) ◽  
pp. 113-116
Author(s):  
M. O. Zhulkov ◽  
A. M. Golovin ◽  
E. O. Golovina ◽  
A. S. Grenaderov ◽  
A. V. Fomichev ◽  
...  
Keyword(s):  
Left Ventricle ◽  
Blood Circulation ◽  
Venous Pressure ◽  
Operation Mode ◽  
Viscous Friction ◽  
Acute Experiment ◽  
Circulatory Support ◽  
Large Mammal ◽  
Pump Operation ◽  
Blood Clots

Objective: to carry out the implantation of an artificial left ventricle of the heart based on a disk-type pump in an acute experiment on a large mammal (mini-pig). Materials and methods. To test the surgical technique of implantation and assess the biocompatibility of the apparatus for mechanical support of blood circulation based on a viscous friction pump, an acute experiment was conducted on an animal. A large mammal (mini-pig weighing 90 kg) was used as an experimental model. The implantation of the pump was performed extracorporeally according to the scheme «the apex of the left ventricle – the descending thoracic aorta». During the experiment, invasive blood pressure, central venous pressure, cardiac arrhythmias, body temperature, blood gas composition, activated coagulation time were monitored. Under the control of transesophageal echocardiography, the pump operation mode was set with parameters – speed 2400–2600, productivity 4 ± 0.5 l/min, average IAD – 70–80 mm Hg. Results. In the course of the experiment, the fundamental possibility of using the developed disk-type pump as a device for supporting blood circulation was proved. For 4 hours, the pump provided adequate hemodynamic parameters with an average productivity of 4 ± 0.5 l/min and 2500 rpm. After 4 hours of operation of the pump in the conditions of inactivated heparin (AST – 114 sec), no blood clots were found between the pump disks. Conclusion The hemodynamics feature of the disk pump allows you to develop sufficient performance parameters to ensure adequate blood circulation. The mechanism of action of the «boundary layer» minimizes the risk of blood clots in the pump cavity. However, the topographic and anatomical features of the pig’s body do not allow experiments with a long observation period.

scholarly journals Optimization of Implantable Axial Pump to Increase Efficiency of Mechanical Circulatory Support

2017 ◽  
Vol 19 (2) ◽  
pp. 61-68
Author(s):  
S. V. Gautier ◽  
A. P. Kuleshov ◽  
A. E. Efimov ◽  
I. I. Agapov ◽  
G. P. Itkin
Keyword(s):  
Shear Stress ◽  
Mechanical Circulatory Support ◽  
Operation Mode ◽  
Flow Region ◽  
Point Of View ◽  
Circulatory Support ◽  
Hydraulic Efficiency ◽  
Pump Operation ◽  
Axial Pump ◽  
Increase Efficiency

Aim. To optimize implantable axial pump to increase hydraulic efficiency and reduce blood hemolysis. Materials and methods. In this article the basic geometric parameters of impeller’s geometry (the blade’s angle, the blade’s length and the twist angle’s ratio) were investigated and optimized using methods of computer hydrodynamics. The calculations were carried out for the optimum operation of the pump at the speed of 8000 rpm. Results. The main parameters of impeller’s geometric were determined which made it possible to increase efficiency of the pump by an average of 7.5% (depending on the pump operation mode) and pressure drop of 8% on average. The value of shear stress in the flow region obtained as a result of the calculations did not exceed 147 Pa admissible from the point of view of blood hemolysis.

Surgical methods of treatment of chronic heart failure and their place in modern clinical recommendations

2020 ◽  
Vol 22 (4) ◽  
pp. 183-191
Author(s):  
O. T. Kotsoeva ◽  
A. V. Koltsov ◽  
V. V. Tyrenko ◽  
A. A. Ialovets
Keyword(s):  
Quality Of Life ◽  
Heart Failure ◽  
Chronic Heart Failure ◽  
Left Ventricle ◽  
Heart Transplantation ◽  
Mechanical Circulatory Support ◽  
Circulatory Support ◽  
Surgical Methods ◽  
The Moment

This review discusses a number of aspects of surgical methods for treating severe chronic heart failure: resynchronizing therapy, mechanical circulatory support systems, and heart transplantation. Surgical methods for the treatment of heart failure are a rapidly developing field of modern cardiology and cardiac surgery. The main surgical method of treatment was and remains orthotopic transplantation of a donor heart. The advent of implantable systems has affected the problem of heart transplantation. Over the past decade, the use of mechanical circulatory support systems has grown significantly. At the moment, there are 3 main directions: creating devices for auxiliary blood circulation, various modes and methods of electrical stimulation of the myocardium, creating devices that mechanically remodel the heart chambers (left ventricle). All of these directions to some extent (depending on the evidence base) have found their place in modern recommendations for the treatment of chronic heart failure. The use of mechanical left ventricular remodeling shows good results in patients suffering from symptomatic heart failure, which leads to a significant and persistent decrease in the volume of the left ventricle and improvement of its function, symptoms and quality of life. Despite the fact that at the moment the geography and prevalence of their use is small, the number of implanted devices will only grow. Thus, given the need for frequent hospitalizations and high treatment costs, it is necessary to improve modern methods of surgical treatment of severe and terminal heart failure, make them more accessible, which will affect the duration and quality of life of these patients.

scholarly journals Improving the operational efficiency of the linear type peristaltic pump

2020 ◽  
Vol 1 (4) ◽  
pp. 16-24
Author(s):  
A.I. Grishin ◽  
Keyword(s):  
Poisson’S Ratio ◽  
Numerical Experiments ◽  
Reverse Flow ◽  
Operation Mode ◽  
Elastic Tube ◽  
Poisson's Ratio ◽  
Maximum Efficiency ◽  
Peristaltic Pump ◽  
Linear Type ◽  
Pump Operation

The paper investigates the effect on the linear peristaltic pump operation of the properties of the material of its elastic tube, the algorithm of actuation of the release elements, as well as the presence of irregularities in the inlet and outlet sections of the pump in the form of alternating confusers and sudden expansions. To study the influence of these factors, a series of numerical experiments was carried out using the universal software STAR-CCM +, where the pump operation was simulated by a joint calculation of the fluid flow and elastic deformations of its tube. As a result of numerical experiments for a number of values of Poisson's ratio, it was found that the material of the pump tube must be selected with the lowest possible Poisson's ratio in order to obtain the highest efficiency. The study of possible algorithms for the actuation of the release elements of the pump showed that in order to obtain the maximum efficiency, the pump operation mode should be select-ed in accordance with the drive design. The drive, where energy is expended only on the movement of the release elements, requires the mode with the first release elements to hold the tube in a com-pressed state longer, which provides a higher feed value. For the drive, where energy is spent on maintaining the tube in a compressed state, the preferred mode is the one with the delay in the re-turn of the release element to its original state is minimal. As a result of studying the influence of sections with irregularities, it was found that the use of the height and pitch of irregularities, when the ratio of the resistances of these sections in the forward and reverse flow is optimal, leads to a decrease in the flow and pressure of pump.

scholarly journals PROSPECTS OF DISK PUMP FOR MECHANICAL CIRCULATORY SUPPORT IN CARDIAC SURGERY (REVIEW)

2016 ◽  
Vol 18 (3) ◽  
pp. 68-73 ◽  
Author(s):  
A. M. Chernyavskiy ◽  
A. V. Fomichev ◽  
T. M. Ruzmatov ◽  
A. E. Medvedev ◽  
Yu. M. Prikhodko ◽  
...  
Keyword(s):  
Support Systems ◽  
Experimental Studies ◽  
Viscous Friction ◽  
Left Ventricular ◽  
Circulatory Support ◽  
Published Data ◽  
Technical Requirements ◽  
New Directions ◽  
Further Development ◽  
Mechanical Heart Support

The need of circulatory support systems in the treatment of chronic heart failure is increasing constantly, as 20% of the patients on the waiting list die every year. Despite the great need for mechanical heart support systems, the use of available systems is limited by its expensiveness. In addition, there is no one system that is 100% responsible to all medical and technical requirements and that would be completely safe for patient. Therefore, further research in the field of circulatory support systems considering health and technical requirements is relevant. One of the new directions in the study are disc pumps of viscous friction for liquid transporting, based on the Tesla pump principle. The operation principle of such pumps is based on the phenomenon of the boundary layer which is formed on the disk rotating in a fluid. There are experimental studies of models with different variants of the rotor suspension, various forms and numbers of the disks, forms of the pump housing. However, none of the above samples was brought to clinical trials. Furthermore, despite the potential of that model there have been no pumps of similar type used so far in circulatory support systems. Published data provide a basis for further development and testing of the pump model and allow hoping for leveling a number of significant shortcomings of modern left ventricular bypass systems. 

scholarly journals BLOOD COAGULATION SYSTEM AND PERSONALIZATION OF TREATMENT IN PATIENTS WITH IMPLANTED SYSTEM OF LEFT VENTRICLE ASSIST DEVICE IN THE EARLY POSTOPERATIVE PERIOD

2020 ◽  
pp. 43-48
Author(s):  
О. П. Мазуренко ◽  
П. Надзякевич ◽  
О. А. Лоскутов ◽  
Л. В. Згржебловська
Keyword(s):  
Left Ventricle ◽  
Blood Coagulation ◽  
Postoperative Period ◽  
Blood Circulation ◽  
Left Ventricular ◽  
Early Postoperative Period ◽  
Coagulation System ◽  
Mechanical Support ◽  
Blood Coagulation System ◽  
Membrane Oxygenation

The work is devoted to the study of the blood coagulation system and the correction of its indicators with a personalized anticoagulant target therapy in the early postoperative period to ten patients with implanted left ventricle assist devices for mechanical circulation support in the Silesian Center Heart Diseases, according to a bilateral agreement with the National Medical Academy of Postgraduate Education named after P. Shupik. The study included ten patients who were implanted in the Silesian Center for Heart Disease from March 11, 2016 to Nov 22, 2017, devices for mechanical support of left ventricular circulation LVAD in the aftermath of the terminal stage of heart failure.The subjects were men 55 ± 13.5 years old, with a body mass index of 30.8 ± 8.3 and a body surface area of 2.12 ± 0.2 m2 with a left ventricular ejection fraction of 15.4 ± 9.5%, which was mechanically supported blood circulation in the period from 11.03.2016 to 22.11.2017 in conditions of artificial blood circulation and combined endotracheal anesthesia, five of which had implanted cardioverts-defibrillators.Patients were divided according to the INTERMAKS Level 1 (cardiogenic shock) - 6 (60% of cases), Level 2 (progressive circulatory failure) - 4 men (40% of cases). Patients in the early postoperative period that time received an anticoagulant target mono and combination therapy with heparin (6-11U / kg / h), Aspirin (75-150mg.), Clopidogrel (75-150mg.), Warfarin (1.5-7mg), Nadroparinum Ca(0.3-0.6 ml / 2p / d), Fondaparinux Na (2.5-5 mg / 2p / d). The duration of support - POLVAD ranged from 102 to 156 days. Results - transplanted 2, died 2. The studies revealed a non-linear relationship between mortality, the number of days of general and intensive therapy for hospitalization, the use of extracorporeal membrane oxygenation and intra-aortic membrane oxygenation in patients with implanted systems of mechanical blood circulation, who used large doses of catecholamines during the postoperative period.Analyzing the needs of patients with implanted mechanical systems to support the blood circulation of the left ventricle in blood donations, it should be noted that in the early postoperative period the erythrocyte mass was most often used. During surgery, fresh-frozen plasma was the drug of choice, while the platelet mass was used in most cases during the pre-operative preparation of the patient.The main complications that developed in patients with implanted mechanical support systems of the left ventricular blood circulation were: bleeding, thrombosis of the mechanical blood circulation systems, cerebral circulation disorders due to hemorrhagic and ischemic type, infectious complications.

INFLUENCE OF ACE INHIBITORS ON RECOVERY OF THE LEFT VENTRICLE IN MECHANICAL CIRCULATORY SUPPORT PATIENTS

ASAIO Journal ◽  
2004 ◽  
Vol 50 (2) ◽  
pp. 124
Author(s):  
A El-Banayosy ◽  
H Milting ◽  
A Kassner ◽  
L Arusoglu ◽  
R Koerier
Keyword(s):  
Left Ventricle ◽  
Ace Inhibitors ◽  
Mechanical Circulatory Support ◽  
Circulatory Support

Modern Mechanical Circulatory Support Devices

2015 ◽  
Vol 25 (2) ◽  
pp. 87-93
Author(s):  
Justas Ovsianas ◽  
Petras Petkevičius ◽  
Norvydas Zapustas ◽  
Giedrė Bakšytė ◽  
Andrius Macas
Keyword(s):  
Intensive Care ◽  
Left Ventricle ◽  
Minimally Invasive ◽  
Mechanical Circulatory Support ◽  
Hemodynamic Instability ◽  
Circulatory Support ◽  
Significant Challenge ◽  
Mechanical Circulatory Support Devices ◽  
Support Devices ◽  
Significant Mortality

Patients with hemodynamic instability when conservative measures are not effective remain a significant challenge for the intensive care specialists. Surgically implantable systems, which require considerable amount of time to insert and a cardiosurgery team, which is not present in smaller medical centres are not applicable in these situations. Significant mortality of patients predispone the develompement of minimally invasive and quickly applicable left ventricle assisting devices. The most commonly used and evaluated percutaneous assist systems are the intra- aortic balloon pump, the Impella pump, the Tandem-Heart and venoarterial ECMO.

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