Surgical treatment of heart failure in China: towards the era of artificial heart / 中华外科杂志

The number of patients with heart failure in China is large, and the proportion of patients with end-stage heart failure continues to increase. The clinical effect of guideline-directed medications therapy for end-stage heart failure is poor. Heart transplantation is the most effective treatment for end-stage heart failure. But it is faced with many limitations such as the shortage of donors. In recent years, the research and development of artificial heart in China has made great progress. Three devices have been approved by the National Medical Products Administration for marketing, and another one is undergoing pre-marketing clinical trial. Since 2017, more than 200 cases of ventricular assist device implantation have been carried out in more than 34 hospitals in China. Among them, 70 patients in Fuwai Hospital, Chinese Academy of Medical Sciences had a 2-year survival rate of 90%. The first patient has survived more than 5 years with the device. More efforts should be put into the training of standardized technical team and quality control. Further research should be carried out in the aspects of pulsatile blood flow pump, fully implanted cable-free device, and improved biomaterial with better blood compatibility.

Multiplicidade e instabilidade ontológica nos corações não-humanos / Multiplicity and ontological instability in nonhuman hearts

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.

Application of hemodynamic optimization in the design of artificial heart / 生物医学工程学杂志

Heart failure is one kind of cardiovascular disease with high risk and high incidence. As an effective treatment of heart failure, artificial heart is gradually used in clinical treatment. Blood compatibility is an important parameter or index of artificial heart, and how to evaluate it through hemodynamic design and

Development and Application of Permanent Magnet Motor and Its Control in the Field of Artificial Blood Pump / 中国医疗器械杂志

Permanent magnet motor has been widely used in the field of artificial heart pump due to its high power density, high stability and easy control. In this paper, the development history and research progress of permanent magnet motor for blood pump were described. Firstly, the motors were classified according to their structures and application scenarios. And then, the measures taken by different types of motors to meet the corresponding performance requirements were introduced, and the specific application cases were given. After that, commonly used control algorithms of these motors were enumerated. What's more, the advantages and disadvantages of the control algorithms and their application emphasis were carefully explained. Finally, the paper was summarized in short.

Dispositivos de assistência ventricular e cuidados de enfermagem / Dispositivos de asistencia ventricular y cuidados de enfermeria / Ventricular assist devices and nursing care

RESUMO Objetivo: descrever o funcionamento, os benefícios e as complicações associadas ao uso de dispositivos de assistência ventricular e identificar as intervenções realizadas por enfermeiros no cuidado ao paciente com este dispositivo, de acordo com as evidências. Método: revisão integrativa, com artigos coletados em bases de dados da saúde, em fevereiro de 2015. Os descritores utilizados foram heart diseases, heart-assist devices e nursing. Identificaram-se 34 artigos, os quais foram submetidos à análise temática. Resultados: os dispositivos de assistência ventricular funcionam como bombas mecânicas promotoras de débito cardíaco adequado. Seu principal benefício é a estabilização hemodinâmica. A complicação mais comum é a infecção. Educação em saúde, suporte emocional, cuidados com sítio de saída e realização de curativo são os principais cuidados realizados por enfermeiros. Conclusão: as evidências comprovam a melhoria da sobrevida de pacientes com insuficiência cardíaca grave com o uso dos dispositivos de assistência ventricular, reiterando a importância da ampliação dessa tecnologia no Brasil como possibilidade de tratamento.

RESUMO Objetivo: describir el funcionamiento, los beneficios y las complicaciones asociadas con el uso de dispositivos de asistencia ventricular e identificar las intervenciones de enfermería en la atención al paciente con este dispositivo, de acuerdo con la evidencia. Método: revisión integrativa, con los artículos recolectados en las bases de datos de salud en febrero de 2015. Los descriptores utilizados fueron heart deseases, heart-assist devices e nursing. Se identificaron 34 artículos, que fueron sometido al análisis temático. Resultados: los dispositivos de asistencia ventricular actúan como bombas mecánicas que promueven gasto cardíaco adecuado. Su ventaja principal es la estabilización hemodinámica. La complicación más común es la infección. educación para la salud, el apoyo emocional, la atención y la realización de vendajes del orificio de salida son la atención primaria por parte de enfermería. Conclusión: la evidencia apoya la mejora de la supervivencia de los pacientes con insuficiencia cardíaca grave con el uso de dispositivos de asistencia ventricular, reiterando la importancia de la expansión de esta tecnología en Brasil como un posible tratamiento.

ABSTRACT Objective: describing the functioning, benefits and complications associated with the use of ventricular assist devices and identifying the interventions performed by nurses in the care of patients using this device, according to presented evidence. Method: an integrative review of articles collected in health databases conducted in February 2015. The descriptors used were heart diseases, heart-assist devices and nursing. We identified 34 articles, which were then submitted to thematic analysis. Results: ventricular assist devices function as mechanical pumps promoting adequate cardiac output. Their main benefit is hemodynamic stabilization. The most common complication is infection. Health education, emotional support, outpatient care and curative care are the main care actions performed by nurses. Conclusion: evidence confirms improvement in survival rates of patients with severe heart failure with the use of ventricular assist devices, reiterating the importance of expanding this technology in Brazil as a possibility for treatment.

Evaluation of factors influencing arterial Doppler waveforms in an in vitro flow phantom

PURPOSE: The aim of this study was to investigate factors that influence arterial Doppler waveforms in an in vitro phantom to provide a more accurate and comprehensive explanation of the Doppler signal. METHODS: A flow model was created using a pulsatile artificial heart, rubber or polyethylene tubes, a water tank, and a glass tube. Spectral Doppler tracings were obtained in multiple combinations of compliance, resistance, and pulse rate. Peak systolic velocity, minimum diastolic velocity, resistive index (RI), pulsatility index, early systolic acceleration time, and acceleration index were measured. On the basis of these measurements, the influences of the variables on the Doppler waveforms were analyzed. RESULTS: With increasing distal resistance, the RI increased in a relatively linear relationship. With increasing proximal resistance, the RI decreased. The pulsus tardus and parvus phenomenon was observed with a small acceleration index in the model with a higher grade of stenosis. An increase in the distal resistance masked the pulsus tardus and parvus phenomenon by increasing the acceleration index. Although this phenomenon occurred independently of compliance, changes in the compliance of proximal or distal tubes caused significant changes in the Doppler waveform. There was a reverse relationship between the RI and the pulse rate. CONCLUSION: Resistance and compliance can alter the Doppler waveforms independently. The pulse rate is an extrinsic factor that also influences the RI. The compliance and distal resistance, as well as proximal resistance, influence the pulsus tardus and parvus phenomenon.

Working Temperature Predication of Artificial Heart Based on Neural Network / 中国医疗器械杂志

The purpose of this paper is to achieve a measurement of temperature prediction for artificial heart without sensor, for which the research briefly describes the application of back propagation neural network as well as the optimized, by genetic algorithm, BP network. Owing to the limit of environment after the artificial heart implanted, detectable parameters out of body are taken advantage of to predict the working temperature of the pump. Lastly, contrast is made to demonstrate the prediction result between BP neural network and genetically optimized BP network, by which indicates that the probability is 1.84% with the margin of error more than 1%.

Do-not-resuscitation in Terminal Cancer Patient / 한국호스피스완화의료학회지

For patients who are near the end of life, an inevitable step is discussion of a do-not-resuscitate (DNR) order, which involves patients, their family members and physicians. To discuss DNR orders, patients and family members should know the meaning of the order and cardiopulmonary resuscitation (CPR) which includes chest compression, defibrillation, medication to restart the heart, artificial ventilation, and tube insertion in the respiratory tract. And the following issues should be considered as well: patients' and their families' autonomy, futility of treatment, and the right for death with dignity. Terminal cancer patients should be informed of what futility of treatment is, such as a low survival rate of CPR, unacceptable quality of life after CPR, and an irremediable disease status. In Korea, two different law suits related to life supporting treatments had been filed, which in turn raised public interest in death with dignity. Since the 1980s, knowledge of and attitude toward DNR among physicians and the public have been improved. However, most patients are still alienated from the decision making process, and the decision is often made less than a week before death. Thus, the DNR discussion process should be improved. Early palliative care should be adopted more widely.

Preparation of Ti-O Film Deposited on the Surface of a New Type of Artificial Mechanical Heart Valve / 生物医学工程学杂志

The rutile structure titanium oxide (Ti-O) film was prepared on the pure titanium material TA2 (99.999%) surface by the magnetic filter high vacuum arc deposition sputtering source. The method can not only maintain the material mechanical properties, but also improve the surface properties for better biocompatibility to accommodate the physiological environment. The preparation process of the Ti-O film was as follows. Firstly, argon ions sputtered to the TA2 substrate surface to remove the excess impurities. Secondly, a metal ion source generated Ti ions and oxygen ions by the RF discharge. Meanwhile a certain negative bias was imposed on the sample. There a certain composition of Ti-O film was obtained under a certain pressure of oxygen in the vacuum chamber. Finally, X-ray diffraction was used to research the structure and composition of the film. The results showed that the Ti-O film of the rutile crystal structure was formed under the 0.18 Pa oxygen partial pressure. A Nano scratch experiment was used to test the coating adhesion property, which demonstrated that the film was stable and durable. The contact angle experiment and the platelet clotting experiment proved that the modified surface method had improved platelet adhesion performance, and, therefore, the material possessed better biocompatibility. On the whole, the evaluations proved the modified material had excellent performance.

Assistência circulatória na insuficiência cardíaca refratária: estado atual das suas indicações e resultados / Circulatory assistance on the refractory cardiac insufficiency: present status of its indications and results

Objetivo: O artigo busca apresentar o cenário atual da terapêutica assistência mecânica circulatória por meio da aplicação de dispositivos artificiais cardíacos aos pacientes portadores de estados avançados de insuficiência cardíaca, por vários tipos de indicações. Métodos: Metodologia descritiva abordando aspectos como remodelamento cardíaco reverso obtido, tipos de dispositivos e das aplicações e desenvolvimento dos modelos, desmame e eventuais aplicações decorrentes e cuidados especiais em pacientes portadores. Resultados: São disponibilizados os resultados do último registro INTERMACS (2012) que listam 4533 pacientes que receberam implante de dispositivos de assitência circulatória no período entre junho 2006 e junho 2011 nos EUA e dados da experiência nacional. Conclusões: Tendo em vista a experiência internacional, observa-se que a aplicação desta modalidade vem aumentando significativamente, consolidando-se como terapêutica coadjuvante no tratamento da insuficiência cardíaca terminal.

This paper describes present stage of the mechanical circulatory assistance by the application of artificial devices in patients with advanced stages of cardiac insufficiency with different treatment indication. Methods: A descriptive methodology was approaching aspects like reverse cardiac remodeling, types of devices and its applications, outcomes and development of the models, the wear and caution with this kind of patient. Results: The last INTERMACS (2012) results are stabilished for 4533 patients who received a ventricular assist device (VAD) implant between June, 2006 to June, 2011 in the USA, and some aspects and experiences in Brazil. Conclusion: We are seen that the international experience regarding the application of this kind of therapeutics is showing a vigorous growth and consolidating like a coadjuvant therapy in the treatment of the cardiac insufficiency.

Biocompatibilidade do polímero da mamona comparada ao implante de titânio para corações artificiais: estudo experimental em cobaias / Biocompatibility of Ricinus comunnis polymer compared to titanium implant used in artificial hearts: experimental study in guinea pigs

OBJETIVO: Determinar se a reação tecidual do implante retroperitoneal do polímero de óleo de mamona (Pm) é significativa ou não por meio de análise histopatológica, tendo como controle o implante de titânio (Ti). MÉTODOS: Estudo experimental, intervencionista e randomizado com 32 cobaias. Os animais foram divididos em quatro grupos iguais e eutanasiados com 7, 20, 30 e 40 dias após o ato cirúrgico. Foram confeccionadas lâminas em hematoxilina-eosina e em tricrômio de Masson. Na comparação dos tipos de material em relação a variáveis quantitativas, foi considerado o teste não-paramétrico de Wilcoxon. Em relação a essas variáveis, os grupos definidos pelo dia do sacrifício foram comparados usando-se o teste não-paramétrico de Kruskal-Wallis. Os resultados obtidos no estudo da fibrose foram expressos por frequências e percentuais. Para a comparação entre os grupos definidos pelo dia do sacrifício, em relação a variáveis qualitativas dicotômicas da fibrose, foi considerado o teste exato de Fisher. Para avaliar a diferença entre os materiais titânio e polímero em cada grupo, ainda em se tratando da fibrose, foi considerado o teste binomial. Valores de P<0,05 indicaram significância estatística. RESULTADOS: A análise das variáveis quantitativas não demonstrou diferença nas reações teciduais entre os materiais (P>0,05). A análise da variável qualitativa também não demonstrou diferença entre as reações teciduais dos materiais (P>0,05). CONCLUSÃO: Não foi encontrada significância estatística entre a reação tecidual do Pm e do Ti.

OBJECTIVE: The aim of the present investigation is to determine if the tissue reaction to the Riccinus communis (mamona) polymer has significant statistical difference compared to the tissue reaction provoked by the titanium implant. METHODS: Thirty two Cavia porcellus were divided into four groups containing eight animals each one. We implanted the two types of materials in the retroperitoneal space of all the animals. They were sacrificed at 7, 20, 30 and 40 days after surgery and the samples were submitted to histological study. RESULTS: The quantitative analysis did not show difference between the tissue reaction of the two materials (P>0.05). The analysis of the qualitative variable also did not show difference between the tissue reaction of the materials (P>0.05). CONCLUSION: Macroscopic and microscopic results showed that the castor oil polymer implant has no significant statistical difference compared to the titanium implant tissue reaction.

Remote surveillance system of artificial ventricular assist device / 中国医疗器械杂志

Performances of reliability and portability are important for artificial ventricular assist devices. This paper presents a remote surveillance system that can observe the condition of the patients and the driving condition of artificial heart online. The system is mainly based on the embedded Compact RIO platform and Ethernet technology. Combined with the driver module of the assist device, this remote system has been tested.

Experiência inicial com a cânula de assistência ventricular TransCore TM / Initial experience with the left ventricular assist device TransCore TM

O choque cardiogênico representa condição associada a elevados índices de mortalidade. Durante décadas, seu tratamento consistiu em drogas vasoativas e balão intraaórtico. Recentemente surgiram os dispositivos de assistência ventricular, porém seu elevado custo inviabilizou o uso disseminado nos sistemas público e privado. Relatamos aqui nossa experiência com a cânula de assistência ventricular TransCore TM, de fabricação nacional.

Cardiogenic shock is a condition associated to high mortality rates. For decades, the treatment consisted of vasoactive drugs and intra-aortic balloon pump. Left ventricular assist devices have been recently introduced, however the high costs of these devices have prevented their widespread use in public and private health care systems. Our initial experience with TransCoreTM, a left ventricular assist device manufactured in Brazil, is reported in this study.

Design and control of a simulating cardiovascular system / 生物医学工程学杂志

In order to study the cardiovascular hemodynamic characteristics and evaluate the artificial heart, especially the compression cardiac assist devices, we put forward a simulating device which is made of pump, valve, tubes and controller, and can be used to imitate cardiovascular system. Moreover, in this essay, we put forth an algorithm to draw pressure-volume loop with the parameters measured, including liquid pressure, volume and air pressure. The changes in the frequency and duty of control signal and in the angle of proportional valve can symbolize cardiovascular system in different heart rates, with different systole period, and at different level, respectively. The result of simulating device experiment proved to be coincident with physiology.

A review of drive system for pulsatile blood pump / 中国医疗器械杂志

Many varieties of pulsatile blood pumps exist in the fields of artificial hearts and ventricular assist devices. Effective sorts can be achieved with the differences in power source and transmission mechanism. Horizontal comparison across different pulsatile blood pumps, together with evolution of similar species is studied to find the commonness and evolution laws for pulsatile blood pumps. After a review of typical pulsatile blood pumps from the angle of power source and transmission mechanism, much analysis is focus on a pulsatile drive structure with flexible electro-hydraulic transmission, and importance of hydraulic transmission to improve the implantation property of pulsatile blood pumps is discussed. Finally new application of electro-hydraulic pulsatile blood pumps in the future, such as the application in Direct Mechanical Ventricular Assistant Device (DMVAD) is given.

Review of wireless energy transmission system for total artificial heart / 中国医疗器械杂志

This paper sums up the fundamental structure of wireless energy transmission system for total artificial heart, and compares the key parameters and performance of some representative systems. After that, it is discussed that the future development trend of wireless energy transmission system for total artificial heart.