Introduction: Increasing the usage of hearts from marginal donors and from donors after circulatory death (DCD) has the potential to expand the donor pool. Such hearts may be resuscitated when subjected to ex vivo perfusion. In addition, this may provide an opportunity for viability testing prior to transplant. We describe a novel ex vivo perfusion system designed to reanimate porcine DCD hearts. The same system was subsequently tested using a human heart from a marginal brainstem-dead donor. Method: In the first phase of the study 23 porcine hearts were procured following circulatory death. All hearts were subjected to a period of primary warm ischemia followed by 120 minutes of hypothermic preservation. The period of hypothermic preservation was initially static cold storage (SCS); then oxygenated machine perfusion and finally a combination of static cold storage and oxygen persufflation via the coronary sinus. Ex vivo perfusion of the hearts was performed with a normothermic, oxygenated blood-based solution in our Langendorff system. In the second phase of the study the same system was used to perfuse a human heart from a marginal brainstem-dead donor. This donor had not met criteria for consideration of heart donation. Results: 15 of the 23 (65.2%) DCD porcine hearts reanimated following reperfusion on the ex vivo system. Reanimation was achieved with 63.6% (7/11) in the SCS group; 33.3% (2/6) in the machine perfusion group and 100% (6/6) in the persufflation group. The human heart was placed in the system after a cold ischemic period of 7 hours 4 minutes and perfused with a mid-thermic temperature solution for a further 2 hours 40 minutes to allow for correction of hyperkalemia before warming. The heart started to work after a further hour and then maintained until the experiment was terminated after a further two hours. Conclusion: The ex vivo perfusion system described can potentially resuscitate marginal hearts including those from DCD. The system devised in this study could also be used as a platform to functionally assess marginal human hearts. This mode of viability testing would be an essential step to determine suitability for transplant.

Introduction: Utilisation of hearts from Donors after Circulatory Death (DCD) could increase the donor pool and stem the decline in heart transplantation. Persufflation is a method of introducing oxygen into the organ during the cold preservation phase. This may offset the effects of warm ischaemia inflicted on the DCD heart, enabling a greater chance of functional recovery. Methods: Seventeen cross-Yorkshire Landrace pigs (divided into three groups) were euthanased humanely by Schedule-1 (intravenous administration of phenobarbitone) or exsanguination. The non-beating hearts were procured after being subjected to 10 - 29 minutes of warm ischaemia. All hearts underwent initial antegrade flush with AQIX® RS-I solution (a novel non-phosphate pH buffered preservation solution). Group I and II hearts were subjected to static cold storage (SCS). The Group III hearts were subjected to retrograde oxygen persufflation via the coronary sinus, at a pressure of 12mmHg, whilst the heart was immersed in cold AQIX® RS-I solution. 10-12 small holes were made in the myocardium, using a 21G needle, to create an outlet for excess oxygen. Reperfusion was performed on a Langendorff modification of Model 30 Functional Circulation circuit, using a mixture of heparinised, leukocyte-depleted blood and AQIX® RS-I solution. Drugs (adrenaline, calcium gluconate, dopamine) and DC cardioversion were used to initiate left ventricular activity. Results:[Figure 1Discussion: DCD hearts subjected to preservation using coronary sinus oxygen persufflation can be successfully reanimated. This study compared persufflation with a retrospective control group (SCS). However, persufflation has demonstrated promise as a potential method for introducing oxygen into the heart during the cold preservation phase, with subsequent ability to achieve sustained reanimation.

PURPOSE:This pilot study aims to assess the viability of using contrast-enhanced ultrasound (CEUS) in renal grafts while they are on hypothermic perfusion machines prior to transplantation. We assessed the vascularity and renal perfusion of machine-perfused porcine kidneys (Maastricht category II) using CEUS.MATERIALS AND METHODS:Five kidneys were placed on hypothermic machine perfusion for up to 24 hours after retrieval. The kidneys were then scanned with a low MI contrast-specific preset and a bolus of 0.5 ml of Sonovue contrast agent was administered. Contrast-specific ultrasound images of the kidney were acquired in 2D and 3D.RESULTS:The five kidneys demonstrated variable flow rates on the perfusion machine (10 - 37 ml/min at 30 mmHg). The CEUS technique demonstrated good perfusion and flow patterns, similar to those seen in vivo, in four kidneys. One kidney had patent arteries up to the interlobar region but no contrast filling in the cortex or medulla. Small perfusion defects were seen in two of the perfused kidneys.CONCLUSION:CEUS appears to be a viable technique for assessing global perfusion and small defects within kidneys prior to transplantation. The flow patterns seen in vitro appear to correspond to those seen in vivo. Further work is required to evaluate the relevance of the flow dynamics measured.

Transplant InternationalVolume 22, Issue s2 p. 1-44 Free Access Monday, 31 August 2009 - Parallel Sessions 1-18 First published: 27 August 2009 https://doi.org/10.1111/j.1432-2277.2009.00957.xAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Volume22, Issues2Special Issue: Abstracts of the 14th Congress of the European Society for Organ TransplantationAugust 2009Pages 1-44 RelatedInformation