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Development of ventricular assist devices in China: present status, opportunities and challenges

The growing number of heart failure patients and the scarcity of organ donors account for the huge need for the development of mechanical circulatory systems, including ventricular assist devices (VADs) and artificial hearts, in China. Several research programmes on blood pumps have been under way for the last three decades. However, unlike in other countries, the development of VADs has been extremely slow, and no system is currently approved and available for clinical application. There are many reasons for this situation. This article provides an overview of the present development of experimental and clinical research on VADs in China. In addition, the challenges for the clinical development of mechanical circulatory support in China are discussed.

Polyurethane Arterial Prosthesis: Experimental Evaluation

Two types of microporous polyurethanes have been evaluated both in vitro and in vivo. In vitro polyurethane disks have been seeded by endothelial cells from bovine aortic origin and from fresh human greater omentum. Various pretreatments permit comparison of six different experimental groups. The benefit of poly L lysine, laminin, fibronectin and previous astrocyte cell seeding is shown. The cell proliferation was assessed daily, using trypan blue in Malassez cells. Cell identification was performed by class I MHC antigen characterization and factor VIII staining. In vivo, 4 mm polyurethane arterial prostheses were implanted as carotid interpositions. Evaluation of polyurethane, both in vitro and in vivo, failed to demonstrate a satisfactory hemocompatibility of the material. However, previous treatment of polyurethane with laminin, fibronectin, and astrocyte cell seeding improves the biologic characteristics of the raw material.

Physiopathologie des anévrismes idiopathiques de l'aorte thoracique ascendante

BACKGROUNDnThe majority of ascending aortic aneurysms cannot be related to any specific etiology and should be qualified as idiopathic. The incidence of this disease is increasing in the population of the developed countries but its pathobiology is poorly understood.nnnAIMnThis article is reviewing the publications concerning the pathobiology of idiopathic ascending aortic aneurysms.nnnSOURCESnA PubMed search on articles published in English or French, between January 1965 and December 2007, on key-words << aortic root >>, << ascending aorta >>, << aortic arch >>, << thoracic aorta >>, << aneurysm >>, << dilatation >> and << dissection >> was undertaken. Articles on aneurysms related to inflammatory and infectious diseases, congenital or genetic syndromes were excluded.nnnRESULTSnThe presented data suggests that destructive remodeling of the aortic wall, inflammation and angiogenesis, biomechanical wall stress, and molecular genetics are relevant mechanisms of idiopathic ascending aortic aneurysm formation and progression.nnnLIMITSnSparse data available from few direct studies offer limited knowledge on pathobiology of idiopathic ascending aortic aneurysms.nnnCONCLUSIONnA more intimate knowledge of the triggers and perpetrating factors of this disease might offer new diagnostic and treatment options.