Overcoming bumps to build little pumps
2018; Elsevier BV; Volume: 156; Issue: 4 Linguagem: Inglês
10.1016/j.jtcvs.2018.05.009
ISSN1097-685X
Autores Tópico(s)Transplantation: Methods and Outcomes
ResumoCentral MessageThe PediaFlow PF4 (LaunchPoint Technologies Inc, Goleta, Calif) device has considerable promise for providing neonates and infants with long-term mechanical circulatory support.See Article page 1643. The PediaFlow PF4 (LaunchPoint Technologies Inc, Goleta, Calif) device has considerable promise for providing neonates and infants with long-term mechanical circulatory support. See Article page 1643. Although heart transplantation is the gold standard treatment for end-stage heart failure, children have the highest waitlist mortality rate compared with adults and other solid organ transplantations.1Almond C.S. Thiagarajan R.R. Piercey G.E. Gauvreau K. Blume E.D. Bastardi H.J. et al.Waiting list mortality among children listed for heart transplantation in the United States.Circulation. 2009; 119: 717-727Crossref PubMed Scopus (289) Google Scholar The mortality is especially high for neonates and infants who weigh less than 5 kg. Larger children and adults can be successfully bridged to heart transplantation with a suite of mechanical circulatory support (MCS) options, with continuous-flow devices incorporating magnetically-levitated rotors as being the current state of the art. However, MCS for infants and neonates represents a critical area of much needed development. Venoarterial extracorporeal life support as a bridge to heart transplantation is associated with poor outcomes.2Dipchand A.I. Mahle W.T. Tresler M. Naftel D.C. Almond C. Kirklin J.K. et al.Extracorporeal membrane oxygenation as a bridge to pediatric heart transplantation: effect on post-listing and post-transplantation outcomes.Circ Heart Fail. 2015; 8: 960-969Crossref PubMed Scopus (51) Google Scholar The Berlin Excor Pediatric (Berlin Heart GmbH, Berlin, Germany) extracorporeal ventricular assist device in this small-sized patient population is also associated with decreased survival.3Almond C.S. Morales D.L. Blackstone E.H. Turrentine M.W. Imamura M. Massicotte M.P. et al.Berlin Heart EXCOR pediatric ventricular assist device for bridge to heart transplantation in US children.Circulation. 2013; 127: 1702-1711Crossref PubMed Scopus (350) Google Scholar These dismal results confirm that heart failure in neonates and infants carries a particularly grave prognosis and that better MCS devices are needed. Because of the relatively small financial incentive for industry to develop advanced MCS devices for children, the National Institutes of Health has supported much of the initial development of these devices.4Baldwin J.T. Borovetz H.S. Duncan B.W. Gartner M.J. Jarvik R.K. Weiss W.J. The National Heart, Lung, and Blood Institute Pediatric Circulatory Support Program: a summary of the 5-year experience.Circulation. 2011; 123: 1233-1240Crossref PubMed Scopus (94) Google Scholar One of these devices is the PediaFlow (LaunchPoint Technologies Inc, Goleta, Calif) infant ventricular assist device and is described in detail in this issue of The Journal of Thoracic and Cardiovascular Surgery by Olia and colleagues from the University of Pittsburgh.5Olia S.E. Wearden P.D. Maul T.M. Shankarraman V. Kocyildirim E. Snyder S.T. et al.Preclinical performance of a pediatric mechanical circulatory support device: The PediaFlow ventricular assist device.J Thorac Cardiovasc Surg. 2018; 156: 1643-1651Scopus (6) Google Scholar This report describes the development and preclinical performance of their PediaFlow device. The most current iteration of the device, the PF4 (LaunchPoint Technologies Inc), can be seen as a miniature counterpart to the most current adult device that has magnetic bearings. These investigators also developed and described the inflow and outflow components for the device, with specific attention to decrease thrombosis. The operating range of the PF4 device is 0.5 to 1.5 L/min—certainly within the CO requirements for most neonates and infants with single or biventricular circulation. In vitro testing showed hemolysis rates comparable with that of the extracorporeal, magnetically-levitated Pedimag device (Thoratec Corp, Pleasanton, Calif). Sixty-day in vivo testing of the PF4 device in lambs revealed favorable biocompatibility and hemolysis, however there were only 2 animal implantations that were carried to this longer time course. Nonetheless, these results indicate significant promise for the Pediaflow PF4 device. The Infant Jarvik 2015 (Jarvik Heart Inc, New York, NY) is another infant ventricular assist device whose development was supported by the National Institutes of Health. This device was supposed to be evaluated in a clinical trial, however because of poor enrollment it has now been placed on hold. A detailed assessment of the Jarvik 2015 was given recently in The Journal of Thoracic and Cardiovascular Surgery.6Adachi I. Burki S. Horne D. Costas G.G. Spangler T. Jarvik R. et al.The miniaturized pediatric continuous-flow device: preclinical assessment in the chronic sheep model.J Thorac Cardiovasc Surg. 2017; 154: 291-300Abstract Full Text Full Text PDF PubMed Scopus (24) Google Scholar It appears that the Jarvik 2015 might be more suited for larger infants and has comparable in vitro and in vivo hemocompatibility. Although a direct comparison of the Jarvik 2015 and PediaFlow PF4 devices is difficult to make without conducting a head-to-head trial, the existing data indicate that both might have similar performance. It would be interesting to see if the hemolysis and thrombotic events would be lower in the PF4 device because of its magnetic bearings and cannula design. The PediaFlow PF4 and Jarvik 2015 represent decades of innovation and commitment of surgeons, engineers, and others to the development of a state of the art miniature MCS device. Numerous bumps in the road have been overcome to yield the current versions of these devices. The field anxiously awaits successful human trials of these devices so that it can then be used to save the smallest and most vulnerable population affected by end-stage heart failure. Preclinical performance of a pediatric mechanical circulatory support device: The PediaFlow ventricular assist deviceThe Journal of Thoracic and Cardiovascular SurgeryVol. 156Issue 4PreviewThe PediaFlow (HeartWare International, Inc, Framingham, Mass) is a miniature, implantable, rotodynamic, fully magnetically levitated, continuous-flow pediatric ventricular assist device. The fourth-generation PediaFlow was evaluated in vitro and in vivo to characterize performance and biocompatibility. Full-Text PDF Open Archive
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