Type 2 Myocardial Infarction and Inpatient Mortality in Septic Shock: Insights from a Nationally Representative Sample

Abstract

Type 2 myocardial infarction (type 2 MI) caused by demand ischemia and characterized by an imbalance between myocardial oxygen supply and demand without acute athero-thrombosis, is common in critically ill patients, including those with septic shock. This study aimed to evaluate the relationship between type 2 MI and inpatient mortality in patients hospitalized with septic shock using the National Inpatient Sample (NIS) from 2016 to 2020. A propensity-matched cohort was constructed, consisting of 31,905 hospitalizations with septic shock and type 2 MI (study group) and an equal number without type 2 MI (control group).

Overall, type 2 MI was not associated with a statistically significant difference in mortality (27% vs 26.1%, OR 1.05, 95% CI 0.97–1.14, p = 0.23). Subgroup analysis revealed an increased mortality risk in younger patients (aged 18–39) with type 2 MI (OR 1.93, 95% CI 1.09–3.43, p = 0.024). Conversely, patients with coronary artery disease (CAD) and type 2 MI demonstrated a lower mortality risk (OR 0.82, 95% CI 0.70–0.96, p = 0.012). Other comorbidities, including chronic heart failure, tachyarrhythmias, chronic kidney disease, and iron deficiency anemia, did not significantly alter mortality outcomes. These findings suggest that type 2 MI may be correlated with inpatient mortality only in specific subgroups of patients with septic shock, particularly younger patients and those with CAD. Our findings underscore the importance of demographic characteristics and comorbidities as key determinants of outcomes. Further research is needed to elucidate underlying mechanisms and improve clinical management in these populations.