Hepatic T1 Mapping as a Novel Cardio-Hepatic Axis Imaging Biomarker Early after STEMI.

Background: The hepatic response after ST-elevation myocardial infarction (STEMI) may be associated with mortality and morbidity. We aimed to assess the cardio-hepatic axis post-STEMI using cardiovascular magnetic resonance (CMR).

Methods: This prospective, observational, single-centre study included consecutive STEMI patients who underwent CMR after primary angioplasty from January 2015 to January 2019. Standard infarct characteristics were analysed, and hepatic T1 and hepatic extracellular volume (ECV) were assessed using pre- and post-contrast T1-mapping sequences. The primary endpoint was the relationship between native hepatic T1-values and ischemic right ventricular (RV) involvement, determined by RV ejection fraction (EF) dysfunction and/or the presence of RV acute myocardial infarction (AMI). The diagnostic performance of hepatic T1 values for detecting RV involvement was assessed using the area under the receiver operating characteristic curve (AUC).

Results: Of 177 consecutive STEMI patients undergoing CMR, 142 were included. Patients with RV ischemic involvement, compared to those without, had significantly higher native hepatic T1 (p < 0.001) and hepatic ECV (p = 0.016). Hepatic T1 values demonstrated a good diagnostic performance in detecting RV involvement (AUC 0.826, p < 0.001) and correlated positively with NT-proBNP values (r = 0.754, p < 0.001). Patients with high hepatic T1 values (>605 ms) had significantly higher NT-proBNP levels (<0.001), larger RV end-diastolic volume (p < 0.001), lower RV-EF (p < 0.001), and a higher prevalence of RV AMI (p = 0.022) compared to those with hepatic T1 ≤ 605 ms, while left ventricular EF and infarct size were similar. Multivariable logistic regression analysis identified RV-EF (p = 0.010) and NT-proBNP values (p < 0.001) as independent predictors of increased hepatic T1 values. Patients with increased hepatic T1 values had a higher rate of re-hospitalization for heart failure at 17-month follow-up (12.1% vs 2.0%, p = 0.046).

Conclusions: Hepatic T1 mapping has emerged as a possible novel imaging biomarker of the cardio-hepatic axis in STEMI, being associated with RV involvement and increased NT-proBNP values.