Abstract Background Metabolic dysfunction-associated liver disease (MASLD) and chronic kidney disease (CKD) are both diseases that can cause increased cardiovascular risk. Recent studies have revealed that the combination of both is a more potent risk factor for ischemic heart disease. However, the mortality and outcomes of patients presenting with acute myocardial infarction (AMI) with varying combination of these two risk factors have yet to be examined. Aims Our research aims to examine the effects of concomitant MASLD and CKD on mortality in patients presenting with AMI. Methods This research examined the features and outcomes of individuals experiencing AMI at our institution. The patients were stratified into 4 groups – patients without MASLD or CKD (MASLD(-)/CKD(-)), patients with MASLD without CKD (MASLD(+)/CKD (-)), patients with CKD without MASLD (MASLD(-)/CKD(+)), and patients with both MASLD and CKD (MASLD(+)/CKD(+)). MASLD was identified as hepatic steatosis along with at least one of five metabolic criteria, and hepatic steatosis was assessed using the Hepatic Steatosis Index. CKD is defined as estimated glomerular filtration rate (eGFR) less than 60 mL/min/1.73 m². A Kaplan-Meier curve was generated to analyse long-term all-cause mortality, and Cox regression analysis was used to identify independent predictors of mortality. Results A total of 6757 patients who presented with AMI were examined over 3.2 ± 2.4 years. Of whom, 3766 (55.7%) individuals were in the MASLD(-)/CKD(-) group, 1945 (28.8%) in the MASLD(+)/CKD (-) group, 675 (10.0%) in the MASLD(-)/CKD(+) group and 371 (5.5%) in the MASLD(+)/CKD(+) group. The MASLD(+)/CKD(+) group had the highest risk of cardiogenic shock compared to their counterparts (p<0.001). The highest 30-day mortality rates were found in the MASLD(+)/CKD(+) group (17.8%), followed by MASLD(-)/CKD(+) (11.6%), MASLD(+)/CKD(-) (4.6%) and MASLD(-)/CKD(-) (4.0%) (p<0.001). In terms of long-term mortality, the Kaplan-Meier curve demonstrated that both MASLD(-)/CKD(+) and MASLD(+)/CKD(+) groups had unfavorable survival following an AMI. Conclusions Patients with AMI, in the presence of concomitant MASLD and CKD, had the highest 30-day mortality rates. They were at the highest risks of AMI-related complications such as heart failure and cardiogenic shock. This study highlights the prognostic impact of cardiovascular-liver-kidney-metabolic health on AMI, and future studies are warranted to mitigate this risk.Figure 1:30 – day all cause mortalityFigure 2:Long term mortality