Search

OBJECTIVES: To establish the optimal machine perfusion temperature for recovery of hearts in a rodent model of donation after declaration of cardiocirculatory death (DCD). METHODS: Hearts from male Lewis rats (n = 14/group) were subjected to 25 min of in situ warm (37°C) ischaemia to simulate DCD. They were then explanted and reperfused with diluted autologous blood for 60 min at 20, 25, 30, 33 or 37°C, after which they were stored at 0-4°C in Custodiol preservation solution for 240 min. Fresh-excised and cold-stored ischaemic hearts were used as controls. The viability of the different groups was assessed by comparing heart rate and left ventricular contractility in a Langendorff circuit, as well as perfusate levels of troponin-t and creatine kinase (CK), and myocardial levels of adenosine triphosphate (ATP) and reduced glutathione. RESULTS: During ex vivo reperfusion, hearts in all groups resumed beating within minutes. The mean heart rate was highest in the 37°C group at 154.72 ± 33.01 beats x min-1 (bpm), and declined in proportion to temperature to 39.72 ± 5.53 bpm at 20°C. Troponin-t levels were highest in the 37°C group (79.49 ± 20.79 µg/l), the values were significantly lower in all other reconditioned groups with a minimum of 12.472 ± 7.08 µg/l in the 20°C group (P < 0.0001). Tissue ATP levels ranged from 4.32 ± 1.71 µmol/g at 33°C to 4.59 ± 1.41 µmol/g at 30°C, all significantly higher than the mean ATP level of 1.41 ± 0.93 µmol/g in untreated ischaemic hearts (P < 0.0001). During Langendorff assessment, the mean heart rate and contractility of all groups were higher than those of cold-stored ischaemic hearts (P < 0.0001), yet not significantly different from those of fresh controls. The perfusate levels of troponin-t and CK, and myocardial levels of reduced-glutathione and ATP were not significantly different between groups. CONCLUSION: Our results suggest that mild hypothermia during ex vivo reperfusion improves recovery of ischaemic hearts in a rodent DCD model. [ABSTRACT FROM AUTHOR]

OBJECTIVES A severe donor organ shortage leads to the death of a substantial number of patients who are listed for transplantation. The use of hearts from donors after circulatory death could significantly expand the donor organ pool, but due to concerns about their viability, these are currently not used for transplantation. We propose short-term ex vivo normothermic machine perfusion (MP) to improve the viability of these ischaemic donor hearts. METHODS Hearts from male Lewis rats were subjected to 25 min of global in situ warm ischaemia (WI) (37°C), explanted, reconditioned for 60 min with normothermic (37°C) MP with diluted autologous blood and then stored for 4 h at 0–4°C in Custodiol cold preservation solution. Fresh and ischaemic hearts stored for 4 h in Custodiol were used as controls. Graft function was assessed in a blood-perfused Langendorff circuit. RESULTS During reconditioning, both the electrical activity and contractility of the ischaemic hearts recovered rapidly. Throughout the Langendorff reperfusion, the reconditioned ischaemic hearts had a higher average heart rate and better contractility compared with untreated ischaemic controls. Moreover, the reconditioned ischaemic hearts had higher tissue adenosine triphosphate levels and a trend towards improved tissue redox state. Perfusate levels of troponin T, creatine kinase and lactate dehydrogenase were not significantly lower than those of untreated ischaemic controls. The micro- and macroscopic appearance of the reconditioned ischaemic hearts were improved compared with ischaemic controls, but in both groups myocardial damage and oedema were evident. CONCLUSIONS Our results indicate that functional recovery from global WI is possible during short-term ex vivo reperfusion, allowing subsequent cold storage without compromising organ viability. We expect that once refined and validated, this approach may enable safe transplantation of hearts obtained from donation after circulatory death. [ABSTRACT FROM PUBLISHER]

The article presents a case study of a 42-year-old patient with malignant pericardial effusion is presented.