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Pediatric Medical Device Day The pediatric medical device course was held at the same time as the MCS/VAD University, and was chaired by George Mychaliska, Farhan Zafar, Angela Lorts, and Lindsay May. Dr. Willem J. Kolff founded the American Society for Artificial Internal Organs (ASAIO) in 1955. Nursing/VAD Coordinator The VAD/Nursing Coordinator track focused on the management and care of VAD patients. [Extracted from the article]

Background: During left ventricular assist device (LVAD) support, the external work performed by the native heart combines with the work performed by the rotary LVAD to provide cyclic flow through the LVAD and, in some conditions, through the aortic valve. In this study, a balance of external work was developed and validated for both full and partial bypass conditions that includes valve opening and aortic compliance. Methods: The theory assumes a steady‐state contribution of external work from the rotary LVAD and a dynamic portion from the heart. Cyclic flow may be ejected through either the LVAD or ascending aorta, and an energy absorption term accounts for aortic compliance. Mock loop studies were performed for LV ejection fractions of 10%–28% combined with HeartMate II LVAD support at 8 and 11 krpm to produce a range of full and partial bypass conditions. The external work of the LVAD and native heart was computed from the experimental pressure‐flow (H–Q) relations and compared to the theory. Results: Native heart contraction produces a counterclockwise loop in the pressure–flow relation of the LVAD which increased with ejection fraction, and during full bypass conditions the external work was preserved in the total systemic flow. During partial bypass conditions, forward flow through the ascending aorta was accompanied by a reversal during aortic valve closure resulting in a reduction in energy in the downstream flow. Conclusions: The study presents a balance of external work during full and partial bypass LVAD support. Experimental data validated the additional terms corresponding to forward flow and aortic compliance that contribute to the system balance. This expanded theory can be applied to LVAD design and control to improve pulsatility and aortic valve biomechanics. [ABSTRACT FROM AUTHOR]

In this Editor's Review, articles published in 2019 are organized by category and summarized. These provide a brief reflection of the research and progress in artificial organs intended to advance and better human life while providing insight for continued application of these technologies and methods. Artificial Organs continues in the original mission of its founders "to foster communications in the field of artificial organs on an international level." Artificial Organs continues to publish developments and clinical applications of artificial organ technologies in this broad and expanding field of organ Replacement, Recovery, and Regeneration from all over the world. Peer‐reviewed Special Issues this year included contributions from the 14th International Conference on Pediatric Mechanical Circulatory Support Systems and Pediatric Cardiopulmonary Perfusion edited by Dr Akif Undar, and the 26th Congress of the International Society for Mechanical Circulatory Support edited by Dr Minoru Ono and Dr Francesco Moscato. Additionally, important editorials highlighted the need for sustainability in hemodialysis, challenges and opportunities in mechanical circulatory support, progress in artificial pancreas development, historical perspectives on ventilators and dialysis, tissue engineering for cardiac support, and regional updates from India and China. Our Pioneer Series continues to highlight the many researchers who created this field of study. This year we debuted a new series entitled "Recent Progress in Artificial Organs" prepared by Vakhtang Tchantchaleishvili and Elizabeth Maynes of Thomas Jefferson University, Philadelphia, PA, USA. This series highlights recent advances and new developments in the field. We take this time also to express our gratitude to our authors for contributing their work to this journal. We offer our very special thanks to our reviewers who give so generously of their time and expertise to review, critique, and especially provide meaningful suggestions to the author's work. Without our dedicated expert reviewers, the quality expected from such a journal would not be possible. We also express our special thanks to our Publisher, John Wiley & Sons, for their expert attention and support in the production Artificial Organs. We look forward to reporting further advances in the coming years. [ABSTRACT FROM AUTHOR]

Due to the high stroke rate of left ventricular assist device (LVAD) patients, reduction of thrombus has emerged as an important target for LVAD support. Left ventricular blood flow patterns with areas of flow stasis and recirculation are associated with platelet aggregation, which is worsened by exposure to high shear stress. Previous reports of intraventricular thrombus in LVAD patients have identified the outside of the LVAD inflow cannula as a nidus for LV thrombus formation. Previous studies of LVAD inflow cannula design have shown a region of low blood velocity and pulsatility at the apex, adjacent to the cannula. One unresolved question is whether the standard practice of inserting the LVAD inflow cannula several mm into the LV could be revised to reduce thrombus formation. To address this, a "tipless" inflow cannula was designed for the EVAHEART LVAS, and assessed in a mock circulatory loop of the LVAD‐supported heart. Customized transparent silicone models of a dilated LV were connected to the EVAHEART LVAS at the apex with a clear polycarbonate inflow cannula for flow visualization using particle image velocimetry (PIV). The "tipless" cannula was inserted flush with the endocardial border and did not protrude into the LV. This condition was compared to the standard cannula position with a 1‐cm insertion into the LV. The Pre‐LVAD condition corresponded to a severe heart failure patient (ejection fraction of 24%) with a dilated LV (180 mL). LVAD support was provided at speeds of 1.8 and 2.3 krpm. At the lower LVAD speed, 63% of the flow passed through the LVAD, with the remainder ejecting through the aortic valve. When LVAD speed was increased, nearly all flow (98%) left the LV through the LVAD. Both LVAD speed conditions produced a vortex ring similar to the Pre‐LVAD condition in diastole. However, the protruding inflow cannula interrupted the growth and restricted the movement of the vortex, and produced areas of low velocity and pulsatility adjacent to the cannula. The tipless cannula exhibited an uninterrupted pattern of the mitral jet toward the LV apex, which allowed the diastolic vortex to grow and aid in the washout of this region. In addition, the tipless cannula increased aortic valve flow, which reduces stasis in the left ventricular outflow tract. The EVAHEART LVAS tipless inflow cannula design improved regional velocity, pulsatility, and vortex formation compared to the standard protruding design, which all reduce the risk of thrombus formation. The clinical significance of the differences observed in the flow field will be dependent on other factors such as the cannula material and surface characteristics, as well as the patients' coagulation status. [ABSTRACT FROM AUTHOR]