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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 Although heart transplantation is the gold standard for advanced heart failure, donor shortage is driving the increasing use of mechanical circulatory support such as left ventricular assist devices (LVADs). Whilst providing an effective therapy, device complications persist and diagnosis remains challenging. Improved non-invasive methods of assessing LVAD function and pathological states are needed. Methods Between 09/05/2018 to 29/08/2018, 17 HeartWare HVAD outpatient patients and those admitted with pump complications were recruited from the St Vincent's Heart and Lung Clinic. A laboratory-based mock circulatory loop was used to simulate pump speed changes, suction states, outflow graft kinks, and haematocrit changes. An electronic stethoscope was used to record audio signals of the pump in vivo and in vitro. Data was analyzed using Welch's power spectral density estimate in MATLAB where amplitude versus frequency graphs were generated, as well as with IBM SPSS. Results Acoustic signature of Heartware was characterised by up to 24 harmonic peaks [31.25-1121Hz] where latter peaks occurred at frequency multiples of the first [31.25-46.88Hz]; this is supported by previous research where all peaks were proposed to be harmonic in nature. Of all peaks, 6 were most prominent [31.25-558.6Hz] and coincided with the 6-peak pattern found in previous research. Harmonic peaks 19, 21, 22 and 23 in the predicted frequency ranges of 570-886.67Hz, 630-980Hz, 660-1026.67Hz, and 690-1073.33Hz were absent. Peak frequency values measured in vivo and in vitro correlated with each other. The frequency distribution of harmonic peaks was positively transposed along the x-axis with increasing speed (linear, R2>0.961). Increasing speed had varying effects on the amplitude of each peak. Inducing suction states increased the amplitude of most peaks except 4 peaks [121.1Hz, 199.2Hz, 238.3Hz, 320.3Hz]. Increasing outflow graft kinks increased the amplitude of all peaks. Increasing haematocrit increased the amplitude of most peaks except 6 peaks [39.06Hz, 78.12Hz, 160.2Hz, 718.8Hz, 800.8Hz, 960.9Hz]. Conclusion With a better understanding of LVAD acoustic signature, deviations can be identified early and used to predict pump malfunction or pathological states. Pump audio signals have the potential to be utilized as a non-invasive method of assessing pump function in the management of LVAD patients. [ABSTRACT FROM AUTHOR]