Reply to 'Hypothermic machine perfusion before viability testing of previously discarded human livers'.

B Replying to b Otto B. van Leeuwen et al. I Nature Communications i https://doi.org/10.1038/s41467-021-21182-8 (2021) We read with interest the comments regarding our VITTAL study report, submitted to I Nature Communications i by Dr. van Leeuwen and colleagues[1], and we would like to take the opportunity to clarify the issues they highlighted regarding our trial novelty, the tested viability criteria, and use of the end-ischaemic normothermic perfusion alone[2]. Machine perfusion is a rapidly developing field that changes many aspects of transplantation medicine, and in the particular context of normothermic liver perfusion (NMP), minimises ischaemia reperfusion injury, allows significantly longer organ preservation, enables liver viability testing, and provides opportunity for therapeutic interventions[3]-[6]. Viability testing and transplantation of marginal livers (VITTAL) using normothermic machine perfusion: study protocol for an open-label, non-randomised, prospective, single-arm trial. 2019; 19: 40. 10.1186/s12876-019-0956-6 17 van Rijn R. Hypothermic oxygenated machine perfusion reduces bile duct reperfusion injury after transplantation of donation after circulatory death livers. [Extracted from the article]