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Due to the current demand for donor hearts, we are increasingly pushing the limits of acceptable organs. Previous literature has shown that prolonged ischaemic time in transport remains a key limitation with excess morbidity such as early primary graft dysfunction requiring VA-ECMO (rates of up to 30% have been reported). This study will highlight outcomes from the first 13 patients who received a donor heart retrieved on the XVIVO hypothermic perfusion organ care device at St Vincent's Hospital, Sydney, Australia. Patient selection was part of the Australia-New Zealand non-ischaemic hypothermic perfusion (NIHP) trial. The first 2 patients selected were part of a run-in period and had a short donor ischaemic time. All subsequent patients selected were estimated to have an ischaemic time exceeding 6 hours. Patients were recruited between November 2021 and September 2022 13 patients received a donor heart procured using the XVIVO NIHP device (8 male, 5 female). Median recipient age was 54 years (range 10-69). Median donor ischaemic time was 404 minutes (range 296-527). 12 patients were successfully weaned from cardiopulmonary bypass post-transplant, 1 patient required VA-ECMO due to secondary graft dysfunction for a duration of 2 days. Median ICU length of stay was 4 days (range 2-37). Median intubation time was 19 hours (13-316). Median post-operative length of stay was 32 days (11-119). There was no post-operative mortality. Our early experience with the XVIVO non-ischaemic hypothermic perfusion device appears very promising. This technology has the potential to overcome limitations associated with prolonged ischaemic time in the field of heart transplantation. [ABSTRACT FROM AUTHOR]

Purpose Driveline infections remain a major complication of ventricular assist device (VAD) implantation. This study aimed to characterize in vivo microbial biofilms causing driveline infections and the degree of tissue integration into the velour of explanted drivelines. Methods Drivelines were obtained from ten VAD patients undergoing heart transplantation at the Alfred Hospital, Melbourne and St Vincent Hospital, Sydney between June 2017 to October 2018. Four uninfected drivelines and six infected drivelines were aseptically sectioned into 10 pieces of 1.5 cm in length, from the smooth tube section at the exit site to the velour section adjacent to the VAD. Organisms on each section were isolated and identified. Microbial biofilms on the infected driveline sections were assessed using scanning electron microscopy (SEM) and viable counts. Computed tomography (micro-CT) and SEM were used to assess tissue integration into each section. All sections were analysed histologically to confirm human matrix protein deposition. Results No organisms were isolated from non-infected drivelines using microbiological culture. Staphylococcus aureus, Pseudomonas aeruginosa , and Staphylococcus epidermidis were found on the velour sections of infected drivelines and correlated with the microbiological culture results from patient swabs of the infected exit site. Although histological analysis found considerable collagen fiber and fibroblast deposition on both the smooth tube and the velour, SEM and micro-CT suggested insufficient tissue integration throughout the driveline velour. Microgaps were observed between the velour fibres, with evidence of microbial biofilms within these gaps. Such biofilms were morphologically distinct from in vitro biofilms grown on biomaterials and might be responsible for the antimicrobial treatment failure. Conclusion This study demonstrated inadequate tissue integration of clinical drivelines in the subcutaneous tissue tunnel, with associated microbial biofilms formed within the microgaps between velour fibres. These data provide important insights into a potentially novel therapeutic strategy against driveline infections that is focused on enhancing tissue integration into the velour, thereby preventing microbial adherence, biofilm formation and migration. [ABSTRACT FROM AUTHOR]

Purpose Stroke and ventricular assist device (VAD) pump thrombus are serious complications that have previously been thought to be related to surgical placement - namely VAD inflow cannula angle. Our aim with this study was to better elucidate the impact of post-operative HeartWare HVAD (left VAD) cannula inflow angle on stroke and thrombus rate within a single centre in Sydney, Australia. Methods Data were extracted retrospectively for all patients who underwent Heartware HVAD implantation from 2007-2017 with accessible on-site CT imaging. BiVAD patients were excluded. Angulation data was available for 95 patients. Post-implant inflow angle was measured between the middle of the inflow cannula relative to the middle of the sternum. All measurements were carried out in the axial plane on CT imaging. Data on Free Haemoglobin level was extracted at 3 intervals (3, 6, and 12-months post VAD implantation). Statistical analysis was carried out using IBM SPSS v25. Results Mean post-operative inflow cannula angle was 89 +/- 27 degrees vs 91 +/- 22 degrees for the non-stroke and stroke groups respectively, p=NS. Similarly, there was no difference in mean post-operative inflow cannula angle between those that formed pump thrombus (89 +/- 28 degrees) and those that did not (91 +/- 19 degrees), p=NS. Average 12-month post-implant Free Haemoglobin was higher in the group with pump thrombus than the group that did not form thrombus (9.1 +/- 9 vs 5.3 +/- 9), p=0.012. Conclusion There was no association between HVAD cannula inflow position and incidence of stroke or thrombus rates in this population. The previous finding of an interaction between inflow cannula angulation and pump thrombosis may be device specific. [ABSTRACT FROM AUTHOR]