Comparison of HTK-Custodiol and St. Thomas Solution as Cardiac Preservation Solutions on Early and Midterm Outcomes Following Heart Transplantation

Objectives: The choice of the cardiac preservation solution for myocardial protection at time of heart procurement remains controversial and uncertainties persist regarding its effect on the early and midterm heart transplantation outcomes. We retrospectively compared our adult heart transplantations performed with two different solutions, in terms of hospital mortality, mid-term survival, inotropic score, primary graft dysfunction and rejection score.

Methods: From January 2009 to December 2020, 154 consecutive heart transplantations of adult patients, followed up in pre- and post-transplantation by two different tertiary centers, were performed at the University Hospital of Lausanne, Switzerland. From 2009 to 2015, the cardiac preservation solution used was exclusively St-Thomas, whereafter an institutional decision was made to use HTK-Custodiol only. Patients were classified in two groups accordingly.

Results: There were 75 patients in the St-Thomas group and 79 patients in the HTK-Custodiol group. The two groups were comparable in terms of preoperative and intraoperative characteristics. Postoperatively, compared to St-Thomas group, the Custodiol group patients showed significantly lower inotropic scores [median (interquartile range): 35.7 (17.5-60.2) vs 71.8 (31.8-127), p < 0.001], rejection scores [0.08 (0.0-0.25) vs 0.14 (0.05-0.5), p = 0.036] and 30-day mortality rate (2.5% vs 14.7%, p = 0.007) even after adjusting for potential confounders. Microscopic analysis of the endomyocardial biopsies also showed less specific histological features of subendothelial ischaemia (3.8% vs 17.3%, p = 0.006). There was no difference in primary graft dysfunction requiring postoperative extracorporeal membrane oxygenation. The use of HTK-Custodiol solution significantly improved midterm survival (Custodiol vs St-Thomas: HR = 0.20, 95% CI: 0.069 -0.60, p = 0.004).

Conclusions: This retrospective study comparing St-Thomas solution and HTK-Custodiol as myocardial protection during heart procurement showed that Custodiol improves outcomes after heart transplantation, including postoperative inotropic score, rejection score, 30-day mortality and midterm survival.