Abstract： Among all kinds of heart diseases, heart failure is the leading cause of death. In recent years, the treatment of terminal heart failure has increasingly become a great challenge to cardiovascular clinical physicians. The limitations of routine medical therapy and surgical interventions, and the shortage of donor hearts have led to the rapid development of mechanical circulation support devices. As the joint research and development of electric machine, mechanical engineering, fluid mechanics, materials science, medical science and some other related subjects, exploring a new type of longterm implantable blood pump has become a hot issue. Axial flow blood pump has the advantages of simple structure, light weight, high flow and efficiency, easy implantation and removal, and at the same time, it does not need to install artificial valves, which can greatly reduce the risk of thrombosis. Compared with the centrifugal pump, axial flow blood pump is smaller and causes much less damage to the blood. At present, axial flow blood pump research has become a focus in cardiac surgery and biomedical engineering field. This article is going to review the operation principles and characteristics of axial flow blood pump, and some key technical issues of current axial flow blood pump research.
Abstract: The ventricle assist device has emerged as an important therapeutic option in the treatment of both acute and chronic heart failure. The blood pumps which are the major components of ventricle assist devices have also progressed to the third generation. The magnetic and/or liquid levitation technologies have been applied into the third generation blood pumps. The impellers which drive blood are levitated in the blood pumps. The third generation blood pumps are mainly composed of the levitation system and the driving system. The development of the third generation blood pumps has three stages: the stage of foreign motor indirectly driving the impeller with the levitation and driving system separated, the stage of motor directly driving the impeller with the levitation and driving system separated, and the stage of levitation system integrated with the driving system. As the impellers do not contact with other structures, the third generation blood pumps possess the advantages of low thrombosis, less hemolysis and high energy efficiency ratio. Currently most of the third generation blood pumps are in the research stage, but a few number of them are used in clinical trials or applying stage. In this article, the history, classification, mechanism and research situation of the third generation blood pumps are reviewed.
Today, the morbidity and mortality of heart failure are increasing year by year in the world. Mechanical circulatory assist devices has been one of the most effective ways to treat heart failure. The experimental study and clinical application of counterpulsation technique are now becoming more and more popular.Intraaortic balloon pump is representative, and has become the most frequently used shortterm mechanical assist device to treat heart failure. Recently, paraaortic counterpulsation device and other new counterpulsation devices have been developing very rapidly. The principle of counterpulsation and its historical background, as well as the development of various counterpulsation devices are reviewed in this paper.