Diastolic dysfunction and early liver allograft dysfunction

We read with great interest the article by Vetrugno et al. who reported the important association of preoperative diastolic dysfunction (DD) and early liver allograft dysfunction.[1](#ref-0001) We salute the authors on this detailed and important investigation, and would like to highlight several points. First, the authors provide the cohort analysis of donors’ and recipients’ demographic variables (Table 1, Ref[1](#ref-0001)), however statistical comparative analysis of the three study groups and these variables is absent. Moreover, additional, important demographic variables (e.g., ethnicity, presence of trans jugular intrahepatic portosystemic shunt; hepato-pulmonary syndrome, porto-pulmonary hypertension, pretransplant hospitalization or vasopressors; QT interval) and intraoperative variables (e.g., hemoglobin, coagulative and thromboelastographic parameters, arrhythmias, immunosuppression, and post-reperfusion syndrome and vasopressors) were not included in the groups’ analysis (Table 4, Ref[1](#ref-0001)). These parameters are predictive of postoperative major adverse cardiac events and unfavorable transplant outcomes.[2,3](#ref-0002) Lastly, an association does not imply causation,[4](#ref-0004) and both DD and early graft dysfunction may have an independent, common origin like cirrhotic cardiomyopathy.[5](#ref-0005) An adjustment for cofounders is, therefore, mandatory; regrettably, the omission of a multivariable analysis from the study obfuscates the interpretation of the observed association. Presumably, DD results in early allograft rejection and dysfunction via the attendant elevated pro-inflammatory cytokines, or increased venous pressure and hepatic allograft congestion.[6](#ref-0006) Postoperative cardiac variables (e.g., troponins, sono- and electrocardiography, venous and pulmonary pressures) and allograft biopsies were not reported in the study, but may direct clinicians to mitigating interventions to improve outcomes in liver allograft recipients with DD.