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Об’єкт дослідження – клапан розподільчий гідравлічної (гідропневматичної) системи механічної підтримки серця з механотронним керуванням. Мета роботи – обґрунтувати створення гідравлічної системи штучного реабілітаційного серця з механотронним керуванням. Дослідити вплив конструктивного параметру одного з елементів клапана розподільчого на витрату і тиск в мембранній камері – штучному реабілітаційному серці. У цій роботі у 8 розділах викладено моделювання та математичне дослідження клапану розподільчого – елемента гідравлічної системи штучного реабілітаційного серця з механотронним керуванням. Надано аналіз вже існуючих систем та обґрунтовано нову пропозицію. Надано вимоги для створення безпечних умов виробництва та експлуатації у відповідних приміщеннях. Викладено стартап-проект. У розділі 1 проведено аналіз і порівняння аналогічних систем механічної підтримки серця. У розділі 2 обґрунтовано нову пропозицію та сформовано вимоги до гідравлічної системи штучного реабілітаційного серця з механторнним керуванням. У розділі 3 наведено 3D-модель, створену за допомогою програми САПР NX 8.5. У розділі 4 викладено обґрунтування математичної моделі. У розділі 5 викладено результати математичного експерименту. У розділі 6 проведено оптимізацію та вибрано найліпший варіант конструктивного параметру для клапана розподільчого за даної математичної моделі. У розділі 7 наведено розробку вимог для приміщення і обладнання для забезпечення безпечної експлуатації та обслуговування об'єкта дослідження. У розділі 8 викладено створення стартап- проекту. Магістерську дисертацію виконано із застосування таких програмних засобів і комп’ютерних технологій, як Microsoft Word (оформлення текстової частини), NX 8.5 (створення клапану розподільчого), MatLab 2020b і Simulink (математичне моделювання, розрахунки, проведення математичного експерименту) та Google Chrome (опрацювання науково-теоретичних та аналітичних матеріалів). The object of the study is the distribution valve of the hydraulic (hydropneumatic) system of mechanical heart support with mechanotronic control. The purpose of the work is to substantiate the creation of a hydraulic system for an artificial rehabilitation heart with mechanotronic control. To investigate the influence of the design parameter of one of the elements of the distribution valve on the flow rate and pressure in the membrane chamber - an artificial rehabilitation heart. In this paper, in 8 chapters, the modeling and mathematical research of the distribution valve - an element of the hydraulic system for the artificial rehabilitation heart with mechanotronic control is described. An analysis of already existing systems is provided and a new proposal is substantiated. The requirements for creating safe conditions of production and operation in the relevant premises are given. The startup project is outlined. Chapter 1 analyzes and compares similar mechanical heart support systems. In chapter 2, the new proposal is substantiated and the requirements for the hydraulic system for the artificial rehabilitation heart with mechanotronic control are formed. Section 3 presents a 3D model created using the CAD program NX 8.5. Chapter 4 describes the justification of the mathematical model. Chapter 5 presents the results of the mathematical experiment. In chapter 6, optimization was carried out and the best variant of the design parameter for the distribution valve was selected for the given mathematical model. Chapter 7 provides the development of requirements for premises and equipment to ensure safe operation and maintenance of the research object. Chapter 8 describes the creation of a startup project. The master's thesis was completed using such software tools and computer technologies as Microsoft Word (designing the text part), NX 8.5 (creating a distribution valve), MatLab 2020b and Simulink (mathematical modeling, calculations, conducting a mathematical experiment) and Google Chrome (processing scientific theoretical and analytical materials).

Resumo O artigo reflete sobre as relações entre corpos biológicos e artefatos tecnológicos, a partir da pesquisa etnográfica sobre o desenvolvimento de tecnologias de assistência circulatória, conhecidas como corações artificiais. Para compreender as corporeidades que tais dispositivos mecânicos ajudam a produzir, buscamos aqui caracterizar dois tipos de corpos instituídos a partir de práticas médicas e biotecnologias projetadas para pacientes com insuficiência cardíaca avançada. Os corpos imunológicos, produzidos a partir dos transplantes de coração, serão contrastados aos corpos biônicos, compostos pelo arranjo com corações artificiais. Propomos que é preciso considerar que cada uma dessas tecnologias se coproduz com distintas naturezas, sustentadas em materialidades, práticas, moralidades e pressupostos específicos. A atenção dada às práticas e à materialidade permitirá destacar os diversos entrelaçamentos materiais-semióticos. Resgatar a trajetória de desenvolvimento desse campo nos permitirá explorar o imaginário a partir do qual tais intervenções emergem, assim como as transformações ocorridas, ressaltando o vínculo ao corpo-máquina tecido no âmbito biomédico. Abstract This paper reflects on the relationship between biological bodies and technological artifacts, based on ethnographic research on the development of circulatory assist technologies, known as artificial hearts. To understand the embodiment that such mechanical devices help to produce, we aim to characterize two types of bodies enacted from medical practices and biotechnologies designed for patients with advanced heart failure. The immunological bodies, produced from heart transplantation, will be contrasted with the bionic bodies, composed of the assembly with artificial hearts. We propose that it is necessary to consider each of these technologies as co-produced with different natures, supported by specific materialities, practices, moralities and assumptions. The attention given to practices and materiality will allow to highlight the various material-semiotic intertwinings. Tracing the development trajectory of this field will allow exploring the imagination from which such interventions emerge and the transformations that have occurred, emphasizing the link to the body-machine woven in the biomedical scope.

We report a case of 15-year-old boy with postlingual bilateral total hearing loss following ototoxic medication during his pediatric intensive care unit stay. The patient received the SynCardia total artificial heart implant (50 mL; SynCardia Systems, Inc., Tucson, AZ, USA) for end-stage biventricular heart failure as a bridge to heart transplant. During his time on the urgent heart transplant wait list, he underwent successful cochlear implantation following optimized coagulation and hemostasis status and appropriate anesthetic preparation. Our case represents the world's first successful cochlear implant in a pediatric patient who received an artificial heart. Despite complexities in this patient population, elective surgical procedures can be performed safely with acceptable morbidity using a collaborative approach with the heart transplant team, including input from cardiovascular surgery, pediatric cardiology, anes thesiology, consultation-liaison psychiatry, physical therapy and rehabilitation, infectious diseases and clinical microbiology, and intensive care unit staff.

– At the of Electric Paton Welding Institute PWI on the basis of previous experience, created an electrosurgical instrument designed to solve the urgent problem of modern abdominal surgery - to stop bleeding in emergencies in the treatment of gastrointestinal ulcers. Known traditional methods of stopping bleeding: mechanical (thread, bracket), electrical, chemical, thermal, etc. have a number of shortcomings that prevent their widespread introduction into surgical practice. The main disadvantages are postoperative complications, tissue re-coagulation, high cost of equipment. The created electrosurgical instrument is developed taking into account the phenomenon of “skin effect". The working surfaces of the tool electrodes have an enlarged perimeter, compared to the traditional shape. This allows to evenly distribute the current density on the surfaces of the electrodes, and free up the central area of the working surfaces of the electrodes for the location of the tube of supply or removal of saline. This tool allows you to perform a quick emergency stop bleeding in the treatment of peptic ulcer disease. It eliminates the existing shortcomings of traditional technologies and can be used to treat patients with an artificial heart rate driver, which significantly expands the range of patients who can be cured. Developed equipment is much cheaper than traditional.Keywordselectrosurgical instrument, abdominal surgery, minimally invasiv e interventions, emergency cessation of bleeding, treatment of ulcers, skin effect.

The Aeson® total artificial heart (A-TAH) has been developed as a total heart replacement for patients at risk of death from biventricular failure. We previously described endothelialization of the hybrid membrane inside A-TAH probably at the origin of acquired hemocompatibility. We aimed to quantify vasculogenic stem cells in peripheral blood of patients with long-term A-TAH implantation. Four male adult patients were included in this study. Peripheral blood mononuclear cells were collected before A-TAH implantation (T0) and after implantation at one month (T1), between two and five months (T2), and then between six and twelve months (T3). Supervised analysis of flow cytometry data confirmed the presence of the previously identified Lin-CD133+CD45- and Lin-CD34+ with different CD45 level intensities. Lin-CD133+CD45-, Lin-CD34+CD45- and Lin-CD34+CD45+ were not modulated after A-TAH implantation. However, we demonstrated a significant mobilization of Lin-CD34+CD45dim (p = 0.01) one month after A-TAH implantation regardless of the expression of CD133 or c-Kit. We then visualized data for the resulting clusters on a uniform manifold approximation and projection (UMAP) plot showing all single cells of the live Lin- and CD34+ events selected from down sampled files concatenated at T0 and T1. The three clusters upregulated at T1 are CD45dim clusters, confirming our results. In conclusion, using a flow cytometry approach, we demonstrated in A-TAH-transplanted patients a significant mobilization of Lin-CD34+CD45dim in peripheral blood one month after A-TAH implantation. Using a flow cytometry approach, we demonstrated in A-TAH transplanted patients a significant mobilization of Lin-CD34+CD45dim in peripheral blood one month after A-TAH implantation. This cell population could be at the origin of newly formed endothelial cells on top of hybrid membrane in Carmat bioprosthetic total artificial heart.

Biventricular heart failure remains a major challenge and total artificial heart (TAH) (SynCardia Systems Inc., Tucson, AZ, USA) bear hurdles, in particular in long-term application. Ventricular membrane rupture of a TAH is a feared complication and often implies a fatal outcome. Hereby we present the first case of successful and effective replacement of a TAH right ventricle due to the membrane rupture.

Background Due to the shortage of organs’ donors that limits biological heart transplantations, mechanical circulatory supports can be implanted in case of refractory end-stage heart failure to replace partially (Ventricular Assist Device, VAD) or completely (Total Artificial Heart, TAH) the cardiac function. The hemocompatibility of mechanical circulatory supports is a fundamental issue that has not yet been fully matched; it mostly depends on the nature of blood-contacting surfaces. Methods In order to obtain hemocompatible materials, a pool of hybrid membranes was fabricated by coupling a synthetic polymer (polycarbonate urethane, commercially available in two formulations) with a decellularized biological tissue (porcine pericardium). To test their potential suitability as candidate materials for realizing the blood-contacting surfaces of a novel artificial heart, hybrid membranes have been preliminarily characterized in terms of physicochemical, structural and mechanical properties. Results Our results ascertained that the hybrid membranes are properly stratified, thus allowing to expose their biological side to blood and their polymeric surface to the actuation system of the intended device. From the biomechanical point of view, the hybrid membranes can withstand deformations up to more than 70 % and stresses up to around 8 MPa. Conclusions The hybrid membranes are suitable for the construction of the ventricular chambers of innovative mechanical circulatory support devices.

Artificial organs 46(1), 71-82 (2022). doi:10.1111/aor.14042, Published by Wiley-Blackwell, Oxford [u.a.]

Accurate device optimization of the Syncardia temporary total artificial heart is difficult while waiting for heart transplantation. In this challenging clinical cohort, using an implantable hemodynamic monitor (CardioMEMS HF system) can assist in volume and hemodynamic assessments. (Level of Difficulty: Advanced.), Central Illustration

The article reflects on the relationships between biological bodies and technological artifacts, based on ethnographic research on the development of technologies of circulatory assistance, known as “artificial hearts”. To understand the corporeality that those mechanic devices help to produce, we aim to characterize two types of bodies, enacted from medical practices and biotechnologies designed for patients with advanced heart failure. The immunological bodies, produced in heart transplantation, will be contrasted to the bionic body, composed of the assembly with artificial hearts. We suggest that considering that each of these technologies gives rise to different natures, supported by materialities, practices, moralities, and specific presuppositions, is necessary. The attention given to the practices and materiality will allow us to highlight the varied material-semiotic intertwinings. Recover the trajectory of development of this field will allow exploring the imagination from which such interventions emerge and the transformations that occur, emphasizing the link to the body-machine on the biomedical scope. O artigo reflete sobre as relações entre corpos biológicos e artefatos tecnológicos, a partir da pesquisa etnográfica sobre o desenvolvimento de tecnologias de assistência circulatória, conhecidas como corações artificiais. Para compreender as corporeidades que tais dispositivos mecânicos ajudam a produzir, buscamos aqui caracterizar dois tipos de corpos instituídos a partir de práticas médicas e biotecnologias projetadas para pacientes com insuficiência cardíaca avançada. Os corpos imunológicos, produzidos a partir dos transplantes de coração, serão contrastados aos corpos biônicos, compostos pelo arranjo com corações artificiais. Propomos que é preciso considerar que cada uma dessas tecnologias se coproduz com distintas naturezas, sustentadas em materialidades, práticas, moralidades e pressupostos específicos. A atenção dada às práticas e à materialidade permitirá destacar os diversos entrelaçamentos materiais-semióticos. Resgatar a trajetória de desenvolvimento desse campo nos permitirá explorar o imaginário a partir do qual tais intervenções emergem, assim como as transformações ocorridas, ressaltando o vínculo ao corpo-máquina tecido no âmbito biomédico.

This biography of serial inventor and medical doctor Willem J. ("Pim") Kolff is written by scientific/historical journalist Herman Broers. The book provides an objective and multi-perspective account of the life and work of Dr. Kolff, who put an undisputed mark on the history of organ-replacement devices by secretly inventing the first clinically functioning hemodialysis machine (in a Nazi-occupied Holland) and later in the United States leading the team that realized the first implantable fully artificial heart. Besides offering a solid historical account, the book also describes the present revival of innovation in the artificial kidney field and contains valuable lessons for a broad variety of readers. Suitable for an audience ranging from medical professionals interested in technology & technologists interested in medicine, to patients & their families, as well as policy makers & research funding parties. The review of this scientific/historic book was composed using the recommendations of Gupta for book reviews of scientific and technical books. Additionally, the reviewer team, composed of a biomedical engineer, a dialysis patient, and a nephrologist, tried to distil some lessons that may be learned from the book.

Irreversible, end-stage biventricular heart failure is associated with mortality rates of up to 100%. Despite the increasing application of ventricular assist devices (VADs), many centers lack experience with total artificial heart (TAH) implantation techniques. We present a surgical technique consisting of the implantation of 2 HeartMate 3 VADs in the setting of a TAH as a bridge to transplantation strategy.

This article describes the properties and performance of a rotary total artificial heart (TAH) that produces inherently pulsatile flow. The hydraulic performance of the TAH was characterized using a mock circulatory loop to simulate four physiologically relevant conditions: baseline flow, increased flow, systemic hypertension, and pulmonary hypertension. The pump has a variable shuttle rate (beats per minute), percentage dwell time, and angular velocity on either side (revolutions per minute), which allows for full control of the flow rate and pulsatility over a range of healthy and pathologic pressures and flow rates. The end-to-end length and displacement volume of the TAH are 9.8 cm and 130 mL, respectively, allowing it to fit in smaller chest cavities including those of smaller adults and juvenile humans.

Background With the limited number of available suitable donor hearts resulting in plateaued numbers of heart transplantations, short- and long-term mechanical circulatory support devices, including the implantation of total artificial hearts (TAHs) are modalities that are increasingly being used as treatment options for patients with end-stage heart failure. The superior vena cava syndrome has been described in this context in various disease processes. We report successful venoplasty for superior vena cava syndrome in a patient with a TAH. Case presentation A 65-year-old man with a history of nonischemic cardiomyopathy had received a left ventricular assist device, and then 2 years later, underwent orthotopic heart transplantation using the bicaval anastomosis technique. The postprocedural course was complicated by primary graft failure, resulting in the need for implantation of a TAH. About 5 months after TAH implantation, he started to develop complications such as volume retention, swelling of the upper extremities, and was diagnosed to have a superior vena cava syndrome. The patient underwent a successful venoplasty of his superior vena cava by interventional radiology with resolution of upper body edema, normalization of renal, and liver function. Conclusion Potential fatal complications caused by catheter or wire entrapment in the right-sided mechanical valve of a TAH have been reported. We describe a safe method for the treatment of superior vena cava syndrome in patients with TAH.

Total artificial heart (TAH) represents the only valid alternative to heart transplantation, whose number is continuously increasing in recent years. The TAHused in this work, is a biventricular pulsatile, electrically powered, hydraulically actuated flow pump with all components embodied in a single device. One of the major issues for TAHs is the washout capability of the device, strictly correlated with the presence of blood stagnation sites. The aim of this work was to develop a numerical methodology to study the washout coupled with the fluid dynamics evaluation ofa total artificial heart under nominal working conditions. The first part of this study focussed on the CT scan analysis of the hybrid membrane kinematics during TAH operation, which was replicated with a fluid-structure interaction simulation in the second part. The difference in percentage between the in vitro and in silico flow rates and stroke volume is 9.7% and 6.3%, respectively. An injection of contrast blood was simulated, and a goodwashout performancewas observed and quantified with the volume fraction of the contrast blood still in the ventricle. The left chamber of the device showed a superior washout performance, with a contrast volume still inside the device after four washout cycles of 6.2%, with the right chamber showing 15%.

BACKGROUND: While ventricular assist devices (VADs) remain the cornerstone of mechanical circulatory support (MCS), the total artificial heart (TAH-t) has gained popularity for certain patients in whom VAD support is not ideal. Congenital heart disease (CHD) patients often have barriers to VAD placement due to anatomic and physiological variation and thus can benefit from the TAH-t. The purpose of this study is to analyze the differences in TAH application and outcomes in patients with and without CHD. METHODS: The SynCardia Department of Clinical Research provided data upon request for all TAH-t implantations worldwide from December 1985 to October 2019. These patients were divided into two groups by pre-implantation diagnosis of CHD and non-CHD. RESULTS: A total of 1,876 patients were identified. Eighty (4%) of these patients also carried a diagnosis of CHD. There was a higher proportion of children in the CHD cohort (16.3% vs. 2.1%, P

Background: The SynCardia total artificial heart (TAH)® is the only approved TAH device. This report summarizes our single-center experience with the SynCardia TAH® with particular focus on the outcome after subsequent heart transplantation. Methods: We retrospectively analysed the outcome of all transplanted SynCardia TAH® patients at our center between 2001 and 2019 in comparison to transplanted left ventricular assist device (LVAD) and biventricular assist device (BVAD) patients and to transplanted patients without prior durable mechanical circulatory support (non-MCS). Results: Only a fraction (n=69; 37.3%) of all SynCardia TAH® patients (n=193) were transplanted. The majority (81.2%) of those were in high-urgency status at the time of transplantation. Survival in transplanted SynCardia TAH® patients was significantly poorer when compared to LVAD-, BVAD- and non-MCS patients (P=0.008). Conclusions: Heart transplantation in SynCardia TAH® patients requires distinct risk stratification to improve outcomes.

With the incidence of end-stage heart failure steadily increasing, the need for a practical total artificial heart (TAH) has never been greater. Continuous flow TAHs (CFTAH) are being developed using rotary blood pumps (RBPs), leveraging their small size, mechanical simplicity, and excellent durability. To completely replace the heart with currently available RBPs, two are required; one for providing pulmonary flow and one for providing systemic flow. To prevent hazardous states, it is essential to maintain balance between the pulmonary and systemic circulation at a wide variety of physiologic states. In this study, we investigated factors determining a CFTAH's inherent ability to balance systemic and pulmonary flow passively, without active management of pump rotational speed. Four different RBPs (ReliantHeart HA5, Thoratec HMII, HeartWare HVAD, and Ventracor VentrAssist) were used in various combinations to construct CFTAHs. Each CFTAH's ability to autonomously maintain pressures and flows within defined ranges was evaluated in a hybrid mock loop as systemic and pulmonary vascular resistance (PVR) were changed. The resistance box, a method to quantify the range of vascular resistances that can be safely supported by a CFTAH, was used to compare different CFTAH configurations in an efficient and predictive way. To reduce the need for future in vitro tests and to aid in their analysis, a novel analytical evaluation to predict the resistance box of various CFTAH configurations was also performed. None of the investigated CFTAH configurations fully satisfied the predefined benchmarks for inherent flow balancing, with the VentrAssist (left) and HeartAssist 5 (right) offering the best combination. The extent to which each CFTAH was able to autonomously maintain balance was determined by the pressure sensitivity of each RPB: the sensitivity of outflow to changes in the pressure head. The analytical model showed that by matching left and right pressure sensitivity the inherent balancing performance can be improved. These findings may ultimately lead to a reduced need for manual speed changes or active control systems.

The aim of this review is to describe the current use, indications, and outcomes of the Syncardia temporary total artificial heart (TAH) (Syncardia Systems, Tucson, AZ, USA), the only TAH currently approved as a bridge-to-transplant strategy in Canada, the United States, and Europe. With more than 1700 implantations worldwide, the Syncardia temporary TAH is the most commonly used pump. Globally, it represents 2% of the long-term mechanical circulatory support devices implanted, with a recent decrease in its use. The main candidates for TAH are heart transplant candidates suffering from acute or decompensated chronic irreversible biventricular failure at high risk of imminent death and for whom a suitable donor is not available. Most patients receiving a TAH are acutely ill, characterized by an INTERMACS profile of 1 or 2, and 20% are under extracorporeal membrane oxygenation. The TAH provides efficient circulatory support and allows the end-organ to recover from the initial hypoperfusion injury. More than 60% of patients implanted with a Syncardia TAH will later undergo transplantation, with a 1-year survival rate of 70% after transplantation, compared with a 1-year survival rate of ∼ 42% in nontransplant patients. Bleeding, infection, stroke, and acute kidney injury are the most common complications in this critically ill population. The new miniaturization of the console (Freedom Portable Driver) facilitates the recovery of TAH recipients by allowing ambulation, aggressive physiotherapy, and, eventually, hospital discharge. This last aspect is one of the main benefits of TAH compared with other biventricular assist devices. In conclusion, the Syncardia temporary TAH is a reasonable bridge-to-transplant option for selected patients with either biventricular failure or special anatomic conditions.

Hemodynamic characteristics of two models of mechanical artificial tricuspid valves of the heart were compared: Tricardix (RF Patent No. 2325874) and MAHV (RF Patent No. 181544). 3D models of the artificial heart valves under study were created. The operational environment conditions were simulated using SolidWorks. SolidWorks Flow Simulation was used for hemodynamic calculations. The efficiency criteria were determined on the basis of the hemodynamic parameters of a native aortic heart valve.

Journal of artificial organs 25(1), 1-8 (2022). doi:10.1007/s10047-021-01273-5, Published by Springer, Tokyo

The usability assessment of a pacemaker is a complex task where the dedicated programmer for testing programmed algorithms is necessary. This paper provides the outcomes of development and complex testing of the artificial cardiac system to evaluate the pacemaker's functionality. In this work, we used the modular laboratory platform ELVIS II and created graphical user interface in LabVIEW programming environment. The electrical model of the heart allows signals generation (right atrium, right ventricle) and the monitoring of the stimulation pulses. The LabVIEW user interface allows to set the parameters of the generated signals and the simulation of the cardiac rhythm disorders as well as the monitoring and visualization of the pacemaker behavior in real-time. The results demonstrate the capability of proposed system to evaluate the paced and sensed pulses. The proposed solution allows the scientists to test the behavior of any cardiac pacemaker for its pre-programmed settings and pacing mode. In addition, the proposed system can simulate various disorders and test cardiac pacemakers in different working modes. Web of Science 73 3 6287 6269

Zielsetzung Patient*innen mit künstlichem Herzersatz sind sowohl im Alltag durch Handys, Rundfunkmasten, Diebstahlsicherungen, RFID-Leser etc. als auch bei medizinischen Behandlungen (Elektrochirurgie, MRT, Strahlentherapie, etc.) dem Risiko von Inferenzen ausgesetzt. Da-her wird in der Forschung nach Möglichkeiten gesucht, Implantate so sicher wie möglich gegen solche Einflüsse zu gestalten. Das Ziel der vorliegenden Arbeit ist daher, jene Eigenschaften zu definieren, die Materia-lien innehaben müssen, um biokompatibel zu sein und gleichzeitig elektromagnetischer Strahlung standzuhalten, damit sie für die Herstellung von Defibrillatoren, Herzschrittmachern und ähnliche Geräte infrage kommen. Methodik Es wurde versucht, mit Hilfe einer systematischen Untersuchung von Quellen Antworten auf die Forschungsfragen zu finden. Insgesamt wurden sechs verschiedene Datenbanken durchsucht, um für diese Arbeit relevante Literatur zu identifizieren. Abschließend wurden die Zusammenhänge der einzelnen Ergebnisse evaluiert. Ergebnisse In Anbetracht der analysierten Studien zu den Auswirkungen verschiedener elektromagnetischer Strahlungsquellen auf biokompatible Materialien in kardiovaskulären Unterstützungssystemen konnten folgende Ergebnisse erzielt werden: Aus allen Metallen konnten lediglich Edelstahl und Titan durch ein geringes Inferenz- und Artefaktrisiko überzeugen. Polymere und Keramiken werden im Allgemeinen nicht von elektromagnetischer Strahlung beeinflusst und können daher ebenfalls als kompatibel für die Herstellung von Kunstherzen angesehen werden. Conclusio Die Ergebnisse der Literaturstudie zeigen, dass eine eingeschränkte Auswahl an klinischen Metallen besteht, die elektromagnetischer Strahlung durch medizinische Eingriffe oder Strahlungsquellen im Alltag standhalten und gleichzeitig als biokompatibel gelten. Im Bereich der Kunststoffe ist eine Beeinflussung jedoch kaum möglich, da EMS keine Auswirkungen auf Polymere hat. Hier stellt der 3D-Druck eine Möglichkeit zur weiteren Forschung nach geeigneten Materialien für kardiovaskuläre Unterstützungssysteme dar. Objective Patients with artificial heart replacement are exposed to the risk of interference both in everyday life from a wide variety of devices that emit radiation (cell phones, radio masts, anti-theft devices, RFID readers) and during medical treatments (electrosurgery, MRI, radio-therapy). Researchers are therefore looking for ways to make implants as safe as possible. The aim of the present work is therefore to define those properties that materials must have in order to be biocompatible and at the same time withstand electromagnetic radiation so that they can be used in the production of defibrillators, pacemakers and the like. Methodology A systematic examination of available sources was used to find answers to the research questions. A total of six different databases were searched to identify literature relevant to this work. Finally, the connections between the individual results were evaluated. Results In view of the analyzed studies on the effects of different electromagnetic radiation sources on biocompatible materials in cardiovascular support systems, the following results could be explained: out of all metals, only stainless steel and titanium could convince with a low risk of interference and artefacts. Polymers and ceramics are generally unaffected by electromagnetic radiation and can therefore also be considered compatible for the manufacture of artificial hearts. Conclusion The results of the literature study show that there is a limited selection of clinical metals that are resistant to electromagnetic radiation from medical interventions or radiation sources in everyday life and at the same time are considered to be biocompatible. As regards plastic materials. In the field of plastics, however, interference is hardly possible be-cause EMS does not have an effect on polymers. Here, 3D printing represents an opportunity to further research into suitable materials for cardiovascular support systems.

BACKGROUND: Patients with end-stage, biventricular heart failure, and for whom heart transplantation is not an option, may be given a Total Artificial Heart (TAH). The Realheart® is a novel TAH which pumps blood by mimicking the native heart with translation of an atrioventricular plane. The aim of this work was to create a strategy for using Computational Fluid Dynamics (CFD) to simulate haemodynamics in the Realheart®, including motion of the atrioventricular plane and valves. METHODS: The accuracies of four different computational methods for simulating fluid-structure interaction of the prosthetic valves were assessed by comparison of chamber pressures and flow rates with experimental measurements. The four strategies were: prescribed motion of valves opening and closing at the atrioventricular plane extrema; simulation of fluid-structure interaction of both valves; prescribed motion of the mitral valve with simulation of fluid-structure interaction of the aortic valve; motion of both valves prescribed from video analysis of experiments. RESULTS: The most accurate strategy (error in ventricular pressure of 6%, error in flow rate of 5%) used video-prescribed motion. With the Realheart operating at 80 bpm, the power consumption was 1.03 W, maximum shear stress was 15 Pa, and washout of the ventricle chamber after 4 cycles was 87%. CONCLUSIONS: This study, the first CFD analysis of this novel TAH, demonstrates that good agreement between computational and experimental data can be achieved. This method will therefore enable future optimisation of the geometry and motion of the Realheart®. ispartof: ARTIFICIAL ORGANS vol:46 issue:1 pages:57-70 ispartof: location:United States status: published

Cardiac tamponade after ventricular assist device or total artificial heart implantation can typically occur within days or weeks after surgery. This report describes the case of a woman who presented over 4 years after SynCardia 70cc total artificial heart implantation, with physiology consistent with right ventricular outflow tract obstruction. The cause was initially attributed to device membrane failure based on the device console waveform; however, during operative exploration, a large amount of proteinaceous exudate was surrounding the device and causing the obstruction. This report illustrates how tamponade can result years after device implantation, secondary to porosity of the outflow grafts.

The CARMAT-Total Artificial Heart (C-TAH) is designed to provide heart replacement therapy for patients with end-stage biventricular failure. This report details the reliability and efficacy of the autoregulation device control mechanism (auto-mode), designed to mimic normal physiologic responses to changing patient needs. Hemodynamic data from a continuous cohort of 10 patients implanted with the device, recorded over 1,842 support days in auto-mode, were analyzed with respect to daily changing physiologic needs. The C-TAH uses embedded pressure sensors to regulate the pump output. Right and left ventricular outputs are automatically balanced. The operator sets target values and the inbuilt algorithm adjusts the stroke volume and beat rate, and hence cardiac output, automatically. Auto-mode is set perioperatively after initial postcardiopulmonary bypass hemodynamic stabilization. All patients showed a range of average inflow pressures of between 5 and 20 mm Hg during their daily activities, resulting in cardiac output responses of between 4.3 and 7.3 L/min. Operator adjustments were cumulatively only required on 20 occasions. This report demonstrates that the C-TAH auto-mode effectively produces appropriate physiologic responses reflective of changing patients’ daily needs and represents one of the unique characteristics of this device in providing almost physiologic heart replacement therapy.

Introduction: Circulatory assistance from a SynCardia Total Artificial Heart (SynCardia-TAH) is a reliable bridge-to-transplant solution for patients with end-stage biventricular heart failure. Ischemic strokes affect about 10% of patients with a SynCardia-TAH. We report for the first time in the literature two successful thrombectomies to treat the acute phase of ischemic stroke in two patients treated with a SynCardia-TAH in the bridge-to-transplant (BTT). Case report: We follow two patients with circulatory support from a SynCardia-TAH in the bridge-to-transplant for terminal biventricular cardiac failure with ischemic stroke during the support period. An early in-hospital diagnosis enables the completion of a mechanical thrombectomy within the first 6 h of the onset of symptoms. There was no intracranial hemorrhagic complication during or after the procedure and the patients fully recovered from neurological deficits, allowing a successful heart transplant. Conclusion: This case report describes the possibility of treating ischemic strokes under a SynCardia-TAH by mechanical thrombectomy following the same recommendations as for the general population with excellent results and without any hemorrhagic complication during or after the procedure.