Abstract Body (Do not enter title and authors here): Background: Major adverse cardiovascular events (MACE) are one of the leading causes of postoperative morbidity and mortality following liver transplantation (LT). Cirrhotic cardiomyopathy (CCM), a subclinical form of cardiac dysfunction, is suspected to contribute to these poor outcomes. Our prior work has identified impaired cardiac reserve as a surrogate marker of CCM. We aimed to investigate the impact of impaired cardiac reserve on cardiac outcomes post-LT.

Methods: Consecutive patients undergoing LT workup with dobutamine stress echocardiography (DSE) between 2010-2018 in the Victorian Liver Transplant Unit (Australia) were included. Cardiac output (CO) was measured at baseline and during low-dose dobutamine infusion at 10μg/kg/min. Impaired cardiac reserve was characterized by an inability to increase CO by >25%. MACE was defined as myocardial infarction, ventricular arrhythmia or heart failure exacerbation by 30 days.

Results: Overall, 494 patients underwent DSE of which 288 (58.3%) proceeded to LT. An impaired cardiac reserve was identified in 97 patients (33.7%). Patients with and without impaired cardiac reserve were similar in terms of age, gender and prevalence of hypertension or diabetes. A significantly higher proportion of patients with low cardiac reserve developed MACE within 30-days of LT [26 (26.7%) vs 29 (15.2%), OR 2.05 (95%CI 1.12-3.72), p=0.018]. This was driven in-part by an increased rate of heart failure exacerbations [7 (7.2%) vs 3 (1.6%), OR 4.87 (95%CI 1.23-19.29), p=0.017]. None of the 10 patients had pre-existing heart failure. Additionally, there was a trend towards increased risk of post-operative atrial fibrillation [OR 1.93 (95%CI 0.98-3.81), p=0.061]. After adjusting for cardiovascular risk factors including age, hypertension, previous heart failure and diabetes; low cardiac reserve remained the strongest predictor for MACE [OR 2.4 (95% CI 1.3–4.3), p=0.004]. There was no difference in long-term mortality rates after a median follow-up of 5.2 years (IQR 2.1-8.7) [HR 0.97 (95% CI 0.61-1.57), p=0.91].

Conclusions: Low cardiac reserve is an independent predictor for development of MACE post-LT. These results endorse the integration of cardiac reserve assessment into CCM diagnostic criteria, and its use in risk stratification of patients undergoing LT. The finding of equivalent survival rates post-LT provides support for the hypothesis that CCM is a reversible entity which may improve following removal of the cirrhotic milieu.